The College at Brockport: State University of New York
Digital Commons @Brockport
Kinesiology, Sport Studies and Physical Education
Faculty Publications
Kinesiology, Sport Studies and Physical Education
1-1-1990
Biomechanics of Cycling and Factors Affecting
Performance
Danny Too
The College at Brockport, dtoo@brockport.edu
Follow this and additional works at: http://digitalcommons.brockport.edu/pes_facpub
Part of the Kinesiology Commons
Recommended Citation
Too, Danny, "Biomechanics of Cycling and Factors Affecting Performance" (1990). Kinesiology, Sport Studies and Physical Education
Faculty Publications. Paper 94.
http://digitalcommons.brockport.edu/pes_facpub/94
This Article is brought to you for free and open access by the Kinesiology, Sport Studies and Physical Education at Digital Commons @Brockport. It
has been accepted for inclusion in Kinesiology, Sport Studies and Physical Education Faculty Publications by an authorized administrator of Digital
Commons @Brockport. For more information, please contact kmyers@brockport.edu.
Review Article
Sports Medicine 10 (5): 286-302, 1990 0112-1642/90/001 J-0286/$08.50/0 © Adis International Limited All rights reserved. SPORT2 333 Biomechanics of Cycling and Factors
Affecting Performance
Danny Too
Depa rtm ent of Heal th, Physical Education and Recreation, Californ ia State Un iversity,
Fullerton, California, USA
Contents
Sum mary ............ ......................... .. .................................................................................... ........ 286 1. Efficiency of Hu man-Powered Veh icles ........ ............................... ...... ..................... ........... 288 2. Cycling Performance in Different Body Positions, Configurations and Orientations ... 288 2.1 pright Versus Supine Orientation ............................................ ...... ....... .. ................. 289 2.2 Upright Versus Prone Orientation ....................... .... .................... ............ .................... 290 2.3 Upright Versus Other Positions ............................
291
2. 3. 1 Low Silti ng Position ............................................... .. ....... .... ........... .............. ........ 291 2.3.2 Semi recumbent Position ......... ........... ...................... ... .................... ..................... 29 I 2.3. 3 Stand-Up Position ..... ....... ..... ....... ........... ............................
.. .......... .............. 292 2.4 Effect of Changes in Body Position/Configuration, and Orientation ............. ..... ... . 293 3. Seat to Pedal Distan ce ................................................................................................ ........ 294 3.1 Seat Height .. ...... .... ......... ................................................... ....... ........... ............ ..... .. ....... . 294 3.2 Crank Arm Length ....................................................... .. .. ........... ........ ................. ... ..... 296 4. Factors Affecting Cycli ng Energy Eltpenditure .................... .. ....................... ........... ... ...... 298 4.1 Workload.. Power Output, and Pedall ing Rate .........
.. ............ ...... ..... 298 5. Co nclusions ................................................................... w.........................
.. ........... 299 w ............................. . ...................... Summary
Cycling performa nce in hu man powered vehicles is affected by the interaction of a
number of variabl es, including environment, mechanica l and human factors. Engineers
have generally focused on the design a nd develo pmen t o f faster, more effI cient human­
powered veh icles based on minim ising aerod yna mic drag, neglecti ng the human com­
ponent, O n the other hand , kinesiologists have exam ined cycling perfo rmance from a
hum a n perspective, but have been constrai ned by the structure of a standard bicycle.
Therefore, a gap exists between research in the vari ous d isciplines. To max imise/optimise
cycling performa nce in human-powered vehicles req ui res a bridgi ng of this gap through
interd iscipl ina ry research.
Cha nges in d ifferent varia bles ca n affect the energy requirem nts of cycling. These
variables include: (a) changes in body posi tion , con figuration. and orien tation; (b) changes
in seat to pedal distance; a nd (c) the interaction of workload, power o utput, a nd pedall ing
rate. Changes in these variables alter join t angles, m uscle lengths, a nd muscle moment
arm lengths, thus affecti ng tbe tension-length, fo rce-velocity-power relati onships of multi­
joint muscles and the effective ness o f force production. This is ultimatel y ma nifested as
a change in the energetics of cycling.
A large num ber of factors affect cycli ng pe rform a nce in human-powered vehicles and
Factors Affecting Cycli ng Pe rformance
287
a gap stili exists betwe n cycling research in various disciplines. To bridge this gaP. if
not completely close it. requ ires cooperation be tween discipLines and further interdisci­
plinary re earch.
In 1933. Francois Faure defeated the world cy­
cling champion. Lemoire. in a 4k.m pursuit and
broke previously establi shed track records (Whitt
& Wilson 1982). What was unique about this feat?
Francois Faure was a relatively unknown cyclist
but he had just defeated the world champion and
he had accomplished this on a nonconventional bi­
cycle, a recumbent bicycle.
Ever since this accomplishment, the U nion
Cycl iste lnternationale (the world governing body
for bic cle racing) banned the use of aerodynamic
devices and recu mbent bicycles from racing com­
petition. They, in essence, have defined a bicycle,
di squalifying any vehicle that may provide an un­
fair aerodynamic advantage to the rider. However,
this has not deterred the technological develop­
ment of recum bent bicycles (as evidenced by the
fo rmation of the International Human Powered
Vehicle Association) nor has it prevent d cyclists
from seeking ways around the ban (as evidenced
by aerodyna mic spokes and frames solid disc
wheels, smaller front wheel, aerodynamic suits and
helmets, etc). This has created a gap between cy­
cl ing research in the various disciplines.
F r instance, designs of llUman-powered vehi·
cles by engineers have always been based on aero­
dynamic factors while neglecting the human com­
ponent. A vehicle would be constructed with a
minimal cross-sectional area and as streamline as
possible with an aerod ynamic fairing to minimise
the drag coefficient. With speeds of some human­
powered vehicles, such as the Vector Si ngle, ex­
ceedi ng 60 mph (96.6 km/h) [Gro s et al. 1983], it
is obvious as to the importance of minimising
aerodynamic drag. But, when the drag coefficient
and effective frontal area has been reduced to 0.033
and 0.152m2, respectively, as in the Vector Single
(compared to 0.3 35 and 1.83m 2, respectively, for
a standard upright bicycle) [Gross et al. 1983], it
is questionable as to how much lower the aero­
dynamic drag can be reduced, and how significant
such changes would be. To further improve per­
formance, it becomes necessary to focus on some
aspect other than the aerodynamic properties. The
most logical area to explore would be the human
engine which powers the vehicle. But, bow efficient
or effective 1$ a cyclist when pedalling in a supine,
semisupine, semiprone, or prone position? What is
the most effective body configuration (hip, knee,
ankle angles) to maxiIJtise force and power pro­
duction and to optimise tensio~-le~gth, force-ve­
locity-power interaction of multijoirit muscles? To
date, there are very few scientific irtvestigations that
have systemically examined the body positions,
configurations and orientations a cyclist should
adopt to maximise performance. Kinesiologists,
unlike engineers, have always examined cycling
performance based on a human factors perspec­
tive. But, these investigations have always been
based on the constraints imposed by the structure
of a conventional bicycle. These investigations have
included the effects on cycling performance with
changes in seat height, crank arm length, pedalling
frequencies, workloads, total work output, etc.
There are a large number of factors affecting cy­
cling performance: environmental factors (e.g.
aerodynamic drag, rolling resistance, bills, bead and
tail winds, altitude); mechanical factors (e.g. wheel
size and inertial properties, friction in power trans­
mission, elliptical chainwheels and cams); biome­
chanical and physiological factors (e.g. muscle
length, joint angle, muscle moment arm length, type
of lever, speed and type of contraction, fibre type
and arrangement, recruitment pattern, etc.) [Burke
1986]. It is beyond the scope of this paper to re­
view all the factors affecting cycling performance.
This paper reviews the literature from a biome­
chanics/energetics perspective and attempts to
bridge the gap between cycling research in the vari­
ous disciplines. Insight is provided regarding the
288
Sports Medicine /0 (5) /990
body configuration, position, and orientation which
maximises cycling performance in human-powered
vehicles.
1. Efficiency of Human-Powered Vehicles
In a comparison between human-powered ve­
hicles and engines, W hitt and Wilson (! 982) in­
dicated that a rider on a bicycle will expend less
kilocalories per kilometer-person when compared
to a moped with rider, an automobile with I or 5
riders, or a diesel commuter train with riders. Even
among animals, a human on a bicycle is ranked
first in efficiency in terms of energy consumed in
moving a certain distance as a function of body­
weight (Wilson 1973). Wilson (I973) states that a
walking human consumes about 0.75 cal/g/km,
which is not as efficient as a horse, a salmon or a
jet transport . With the aid of a bicycle, however,
energy consumption for a given distance is reduced
to about 0.15 cal/g/ km. This 5-folo increase in ef­
ficiency appears to be accompanied by a 3- or 4­
fold increase in travelling velocity (Wilson 1973).
This, according to Dill et al. (1954), makes cycling
2.5 times easier than walking.
At speeds greater than 8 m/ sec (18 mph) air re­
sistance accounts for more than 80% of the total
force acting to slow a human-powered vehicle such
as a standard bicycle (Gross et al. 1983). Because
the force of aerodynamic drag increases as the
square of the velocity, and the power necessary to
drive an object through this resistance increases as
the cube of the velocity (Faria & Cavanagh 1978),
it is logical to assume that any change to a vehicle
which can alter its aerodynamic properties will en­
hance the performance of that vehicle given the
same energy input. It is well documented that re­
cumbent human-powered land vehicles are more
effective aerodynamically than the standard up­
right seated bicycle (Kyle 1974, 1982; Kyle &
Caiozzo 1986; Kyle et al. 1973, 1974; Whitt 1971 ;
Whitt & Wilson 1982). In different investigations,
cycling time to exhaustion, power output and oxy­
gen consumption was found to be greater in a
standard cycling position than in nonupright po­
sitions (Diaz et al. 1978; Metz et al. 1986, 1990).
The potential use of hu man-powered vehicles as
an efficient mode of transportation is not just lim­
ited to usage on land. An underwater bicycle has
been shown to reduce human oxygen requirements
by almost 40%, yet increase his propulsive effec­
tiveness by as much as 1.6 times compared with
underwater swimming with fi ns (Baz, 1979). The
use of a human-powered vehicle as a viable mode
of air travel has been demonstrated by the Gos­
samer Albatross, the first human-powered aircraft
to cross the English Channel (Drela & Langford
1985). It required a human power output of 0.25
hp (18 o.5W) and had a cruising speed of 12 mph
(5.4 m/ sec) [ME Staff Report 1984].
2. Cycling Performance in Different Body
Positions, Configurations and
Orientations
The terms body position, body configuration and
body orientation are all interrelated, and are often
used interchangeably in the literature. In this pa­
per, the body position refers to the location of the
cyclist relative to the pedal axle of the bicycle and
is determined by the angle of the bicycle seat tube
and a vertical line (perpendicular to the ground)
passing through the pedal axle. The term body con­
figuration refers to the posture of the cyclist as de­
fined by the angles of the different body segments
(hip, knee, ankle) relative to each other. The term
bod y orientation refers to the posture of the cyclist
as defined by the angle of the cyclist's trunk rela- ' .
tive to the ground (fig. I).
There is a plethora of literature discussing how
performance (as determined by maximal velocity)
in human-powered vehicles can be improved by
altering the cycling body position into a more aero­
dynamically effective one (B'oor 1981; Kirshner
1985; Kyle 1974, 1981 , 1982; Kyle et al. 1973, 1974;
Kyle & Edelman 1975; Malewicki 1984; Martin
1979; Nonweiler 1956, 1957). However, most of
the literature investigating human performance
while cycling in different positions have involved
only upright and supine body orientations (Beve­
gard et al. 1960, 1963; Bishop et aI.,1 956; Conver­
tino et aI. 1984; Cumming 1972; Dickhuth et aI.
289
Factors Affec ting Cycling Performance
1978; Faria et al. 1978; Metz et al. 1986, 1990;
Montgomery et al. 1978; Too 1988, 1989a,b, 1990),
and only Too (1988, 1989a,b, 1990) has investi­
gated the effect of systematic changes in body po­
sitio n, configuration , and orientation on cycling
performance.
2.1 Upright Versus Supine Orientation
Fig. 1. Definition of body position (seat tube angle . top) body
configuration (hip angle. centre) and body orientation (trunk or
backrest angle. bottom).
1981 : Ekelund 1966, 1967a,b; Galbo & Pauley 1974;
G ra nath et al. 1961 ; Gullbring et al. 1960; Holm­
gren et al. I 960a,b; Kubicek & G aul 1977; Reeves
et al. 1961; Sten berg et al. 1967; Ti mmons 1981).
Very few studics have investigated these responses
in other body positions or orientations (D iaz et al.
Of the studies investigating physiological re­
sponses in the upright and supine body orienta­
tio n, it has been reported that a greater max imal
work output and maximal oxygen consumption can
be obta ined when cycling in a standard upright ori­
entation. Kubice k and Gaul (1977) indicate that
the maximal workload obtained was higher in the
sitting than in the supine orientation, although the
differences were not statistically significant. As(rand
and Rodahl (1977) state that ' in maximal work on
a bicycle ergometer in the supine position. the oxy­
gen uptake is only about 85% of the value obtained
in the sitting position' (p. 305). T his would suggest
that an uprigh t orientation may allow a greater work
output to be accomplished as well as e liciting a
larger maximal oxygen consumption .
At submaxima1 workloads there appears to be
conflicting evidence whether oxygen consumption
values are smaller when pedalling in the supine
orientation or are similar in the supine and upright
orientations. Bevegard et a!. (1960, 1966) reported
the oxygen consumptions to be very similar, with
statistically nonsignificant differences at submaxi­
mal workloads in com parisons between supine and
upright cycling orientations. Con vertino et al.
(1984) indicated that although the oxygen con­
sumption at steady-state for a submaximal work­
load was sim ila r for both the supine and upright
orientation (1.66 L/min and 1.65 L/ min, respec­
tively), the su pine oxygen consumption values dur­
ing the initial 3 minutes of exercise and l he total
exercise oxygen consumption was significantly
sm al ler (p < 0.05) than the upright orientation.
Timmons (1981) fo und significantly [ower oxygen
consumption (p < 0.0 I) values for submaximal
workloads (200, 400, 600 and 800 kpm) in the su­
pine orientation when compared to the upright ori­
290
Sports Jll'dicinl' 10 (5) 1990
entation. T hese di ffere nces were slated to be quite
small (mean d iffe rence of 5.4% or 76 ml/min be­
twee n the 2 ori nta tions wh ich amounted to less
than I mljkg/min). On the other hand, Granat h et
al. (1964) repo rted a su bm aximal workload corre­
sponding to 84% and 67% of the ma xima l working
intensity for the su pine a nd si tting orientation, re­
spectively. T o add to the con fus ion, Bevegard et
al. ( 1963) repo rted sign ifican tly lowe r (p < 0.05)
oxygen co ns um ption va lues for a submaxi mal
workload at 800 kpm in the supine orientation, but
no significant differences (p > 0.05) a t a subma x­
imal wo rkload of 1600 kpm when co mpared with
the upright orientation.
Similar diffic ulties exist when attempting to
com pare cycling efficiency between su pi ne and up­
righ t bod y orientations. Be vegard et a!. ( ! 960) and
Convert ino et a l. (1984) reported n o signifi cant dif­
feren ces in efficiency between the su pi ne a nd up­
right orie ntations. Howe ver, physiol ogica l base­
lines were no t con sidered by Convertino et al.
(1984) in the effi ciene_ calculations. Bevegard et
al. (1963) accounting fo r physiological baselines,
foun d cycling effi ciency to be sign ificantly greater
in the supine orientation (25.3% vs 23.8% in the
uprig ht) at a submax imal workload of 800 kpm/
min, but not sign ifi cantly greater at 1600 k pm/min
(24.6% in the supine to 24.4% in the sitting ori­
entation). Based on the evidence repo rted in the
literature regard ing oxygen consu m ption in the su­
pin e and upr ight orientation, changes in body ori­
entation may affect 'ycli ng work output, energy ex­
penditure, and efficiency. Ho wever, there was no
indicatio n whether the bod y configuration (hip,
knee, ankles) in the supine a nd uprigh t orientation
was standard ised or contro lled for. Di fferenc.es in
body con fi guration will alter joi nt angles, muscle
moment arm lengths and their resulting inte rac­
tions in the tension-length curve, th us possibly
confoundi ng the data and results.
2.2 Upright Versus P rone O rientation
Faria et al. (1978), in a comparison between a
top bar and drop bar cycling posture, reported t he
maximal oxygen uptake for the drop bar posture
to be greater (both in L/min and ml/kg/min) than
that attained for the top bar posture (p < 0.05 and
p < 0.01, respecti vely). It should be noted that the
term position is used by Faria et at. U 978) instead
of posture. But, to avoid confusion, and to be con­
sistent with the terms defined in thi s paper, posture
will be used instead.
A top bar posture is described by Faria et al.
( 197 8) as sitting semi-upright on the sadd le with
the hands resting on the uppermost portion of the
handlebars, wh ile a drop bar posture is described
as sitti ng in the saddle while assuming a deep for­
ward lean, wi th the hands resting on the drop por­
tion of the turned-down handlebars. It should be
noted that this deep forward lean in the dropped
bar posture can be ~ss umed to place the torso in
a prone or semi-prone position. The dro p bar pos­
ture was also reported to have a signi fi cantly greater
(1.2 times greater, p < 0.05) maxi m al work output
(in kpm and kpm/kg bodyweight) than Ihe top bar
posture, although the max,imal hcart rate for both
postures were not significantly different. It is in­
teres1.ing to note that Faria et aI. (1978) indicated
that the oxygen uptake at a physical work capacity
with a heart rate of 170 beats/min represented 84%
of the maximum oxygen uptake (ml/kg/m in) for
both cycling postures, although the absolute values
were significantly greater (7% greater with p < 0.0 I)
for the drop bar posture. 'I his would suggest that
for the 2 different riding postures, the absolute en­
ergy expenditure may be different for submaximal
workloads, whereas the relative energy expended
may be the same. These differences were believed
to be attributed to: (a) the activity of a larger muscle
mass (greater use of the arm , shoulder girdle, and
lower bac.k m uscles) in the drop ba r posture; and
(b) the greater forward body lean angle in t he drop
bar posture which appears to re lieve the weight of
t he arms a nd shoulder girdle from the thorax. T his
reduc d we ight plus the su spended chest is be­
lieved to ease chest expansion, thereby en hancing
pulmonary ve ntilation pote ntia l a nd possibly de­
creasing the energy req ui re ment for respiration
(Faria et at. 1978),
T his study wo uld suggest that different body
orienta ti ons will result in d ifferent maximal work
Factors Affecting Cycling Performance
output and possibly energy expenditures (depend­
ing on how energy expenditure is calculated). How­
ever, it is unknown whether the greater lean in the
drop bar posture altered the hip angle and placed
the working muscles and muscle moment arm
lengt h in a more mechanically advantageous po­
sition to produce force when compared to the top
bar posture. The hip, knee, and ankle angles were
not reported and do not appear to have been con­
trolled for.
2.3 Upright Versus Other Positions
2.3. 1 L ow Sitting Position
The physiological responses when comparing
cycli ng in an upright position to other positions
would appear to favo ur the upright position. Diaz
et ai. (1978) reported significantly greater (p < 0.05)
maximal oxygen consumption in an upriglll posi­
tion (3.68 L/m in or 49.8 mllkg/ min) than in a low
sitting position (3. 32 L/ min or 44.7 ml/ kg/ min). A
low sitting posit jon is described by Diaz et aI. (1 978)
to be a cycling position where the torso is upright
and the legs horizontally extended. T his indicates
that greater maxi mal work output was achieved in
an upright position because there is a direct rela­
tio nship between maximal oxygen consumption
and maximal work output. Oxygen consumption
at submaximal workloads of 360 and 720 kpm/ min
was foun d to be similar in both the low sitting p0­
sition ( 14.7 and 24.7 mllkg/ min) and in the upright
position (1 4.6 and 25.7 ml/kg/min). However, for
each submaximal workload, the relative oxygen
con umption (relative to the maximal value of each
position) was found to be greater for the low sitting
position (33 and 55%, respectively, vs 30 and 52%
fo r the upright position). Despite these differences
in relative oxygen consumption, Diaz et al. (1 978)
fOllnd similar efficienci s between the 2 sitting p0­
sitions for each submaximal workload. It is un­
know n as to what these differences were attributed
to. Diaz et a1. (1978) did not report whether phys­
iological baselines were accounted for in the effi­
ciency cal ulations or what the seat to pedal dis­
tances and cycling range of h ip, knee, and angles
were fo r tile different seating positions.
291
A similar investigation had been done by Hugh­
Jones (194 7) ~n the efficiency of bicycle pedalling
in different seating positions. It involved moving
a bicycle seat, with an added backrest, into 7 dif­
ferent positions (3, 26, 43, 53, 63, 73 and 83°)
around the arc of a circle whose centre was the
pedal axle. The seating position was defined by the
angle formed between the perpendicular and the
line joining the base of the seat backrest to the pe­
dal axle. Submaximal oxyge,?- consumption values
plotted with different positions did not reveal any
particular trends. However, Hugh-Jones (1947) did
indkate that cycling in the normal saddle position
(26°) and in a 63° seat position resulted in lower
oxygen consumption values than the other posi­
tions, although they were not signiffcantly different
from each other. The contribution of the leg weight
and use of the backrest were given as explanations
for the lower oxygen consumption values found in
the normal and 63° saddle positions, respectively.
The lack of any trends in oxygen consumption and
nonsignificance with different seating positions
might have been attributed to the large variances
associated with small sample sizes (in this case,
n = 2) and/or not having accounted for possible
differences in physiological baselines of the differ­
ent positions. Actual efficiency calculations were
not made, comparisons of energy expenditures and
seat to pedal distances were not reported, nor was
there any indication regarding the body configur­
ation (hip, knee, ankle angles) and orientation in
the different cycling positions. The only reference
made to body orientation was with the 63° posi­
tion. Hugh-Jones (1947) described the 63° position
as corresponding with the position adopted in the
French 'Velocar' (a semirecumbent bicycle).
2.3.2 Semirecumbent Position
In a comparison between an upright racing p0­
sition and a semi recumbent position, Metz et aI.
(1986, 1990) found cycling performance to be su­
perior in the upright position. Metz et aI. (1986,
1990) examiIti,ng the leg motion during standard
and semirecumbent bicycle pedalling, reported that
cycling time to exhaustion in a semirecumbent po­
sition was consistently 4 to 5 minutes less than that
292
on a standard racing bicycle when tested using a
wind load simulator. The test protocol was re­
ported to consist of a riding regimen similar to that
used by the US National Team for fitness trials,
with a complete test lasting about 16 minutes. In
comparing equivalent workloads and power out­
puts at successive levels, it was determined that the
subject tested (an elite cyclist) was unable to main­
tain the requi red power output or tolerate the
equivalent workload for the same duration on a
sem irecumbent bicycle when compared to a stand­
ard racing bicycle. It was speculated that experi­
enced cyclists migh t have developed certain coor­
dination patterns or motor programmes which
allow them to be more effective and efficient on
standard bicycles. This could account for the dif­
ferences in performance times although Metz et at.
(1986, 1990) had indicated that the rider was given
ample opportunity to practice on the semirecum­
bent bicycle.
Although the sem irecumbent bicycle positioned
the cyclists' legs in a dramatically different orien­
tation with respect to the gravity field, no clear dif­
fe re nces in joint forces or moments were found by
Meiz et at. (1986, 1990) when compared with the
standard position. Because instrumented pedals
were not used and force data was not available, it
is unknown whether d ifferences in cycling per­
formance was attributed to varying leg weight con­
tribution in the different cycling position s. Also,
because physiologicat data (oxygen consumption,
heart rate, etc.) was not coilected, it is difficult to
ascertain whether d ifferences in performance be­
tween the 2 cycling positions were attributed to dif­
ferences in efficiency, oxygen consumpt ion, abso­
lute, and/or relative energy expenditure, or some
other parameter. It can be assumed that differences
in performance (based on visual observations of
the reported cycling positions) were probably at­
tributed to differences in the muscle length and
muscle moment arm length interactions by virtue
of the 2 different body configurations.
2.3.3 Stand-Up Position
T here is a question of whether a change in body
position and/or orientation altering the leg weight
contribution to the force applied on the pedal,
Sports Medicine IO (5) 1990
wo uld affec t the physiological response to cycling
performance. Montgomery et al. (1978), in com­
paring the maximal oxygen consumptions between
an upright seated position and a stand-up position,
reported no significant differences between posi­
tions. No evidence was given whethcr submaximal
workloads elicited similar or different oxygen con­
sumption values. Nonsignificant maximal oxygen
uptake between the two positions would indicate
that the weight of ,the leg in contributing to cycling
work performance may not be important. If the leg
weight was a significant factor in affecting the max­
imal workload attained and the energy expended.
one would assume that a stand-up position would
enable a cyclist to shift his bodyweight more from
side to side. This ' should allow a greater contri­
bution of the bodyweight to the total force on the
pedals, which in turn, should reduce the metabolic
demands on the body. In contrast, Kamon et al.
(1973), investigating the effects of climbing and cy­
cling with additional weights on the extremities,
indicate the oxygen cost per unit when cycling on
an ergometer with ankle weights is less than that
without ankle weights. This extra weight around
the ankles was believed to assist the muscles in
moving the pedals against the resistance. However,
one would expect the weight contributed by one
leg to the pedal on the downstroke would probably
be negated by the weight of the other leg resting
passively on the pedal during the upstroke. This is
supported by data indicating a net downward force
on the pedals during the upward (recovery) stroke
as well as during the downward (power) stroke
(Redfield & Hull ' i 986a,b; Soden & Adeyefa
1979a,b). Questions related to the possible contri­
bution of forces when pulling up on the toeclips
can best be answered by a brief review of the cy­
cling literature involving instrumented pedals.
There are many cycling investigations involving
the use of force pedals (Bolourchi & Hull 1985;
Cornelius & Seireg 1986; Daly & Cavanagh 1976;
Davis & H ull 1981, 1982; Ericson & Nisell 1988;
Ericson et al. 1988; Hu ll & Davis 1981; Hull &
Gonzalez 1988; Hull & Jorge 1985 ; Hull et al. 1988;
Jorge & Hull 1984; KunstIinger et al. 1984; Mc­
Cartney et at. 1983; Redfield & Hull 1986a,b; Sar­
Factors Affecting Cycling Performance
gent & Davies 1977}. The forces recorded on an
instrumented pedal , as reported in the lit rature,
vary with tbe test protocol and phase of the pedal
cycle. Mean peak normal forces on the pedal were
found to occur in the 90 to 11 0° range of the pedal
cycle (wit h 0° as top dead centre and 180° as bot­
tom dead centre). These forces varied from 250 to
570N, with peda ll ing fr quency ranges from 60 to
120 rp m, and power outputs from 98 to 778W
(Brooke et al. 198 J; G regor & avanagh 1976; Gre­
gor ct al. 1985; Lafortune & Cava nagh 1980, 1983;
Redfield & Hull 1984; Sargent et al. 1978).
Soden and Adeyefa (l979a,b) ind icate a rider
starting on level ground and accelerating at 2.6
m/ sec 2 was estimated to apply a force of 1448N
(more than twice his bodyweight) to the forward
pedal and with a p ull of 367N (0.56 times body­
weight). With a power output of 770W and a con­
stan t pedalling freq uency without acceleration , the
maximum pull on the rear was reported to be less
than lOON ; and lower workloads did not result in
a pull on the rear pedal. The absence of a pull-up
force during the recovery appears to be supported
by va rious investigations when cycling with a large
inertial load and with a constant pedalling cadence
(Gregor 1976; Hoes et al. 1968; Lafortune et al.
1983). This would be similar to cycling on the level,
but would be d ifferent when compared to sprinting
or hill climbing. T he force production pattern in
different phases of the pedal cycle and the effect of
toecli ps and pu lling on the pedals in nonconven ­
tional cycl ing position is unknown .
2.4 Effect of Cha nges in Body Position/ Configuration and Orientat ion To determ ine the most effecti ve seating ar­
ra ngemen t that would maxim ise cycl ing perform­
ance regardless of the type of human-powered ve­
hicle, would require a systematic manipulation of
body position/ configuration while controlling for
body orientation and vice-versa. U nfortunately,
most human-powered vehicles constructed to es­
tablish new speed records are design ed to minimise
ae rodynamic drag, without any other justification
293
as to why the performer should be seated in a cer­
tain position.
Too (198 8, 1989a, 1990) in examining the effect
of systematic manipulation of 5 body positions
(bicycle seat tube angles) and configurations (hip
angle) o n cycling performance while controlling for
body orientation , concluded that an optimal cy­
cling body position /configuration exists that ma x­
imised aerobic and anaerobic work. For aerobic
work, 16 male subjects were tested in 5 seating po­
sitions (0, 25 , 50, 75 and 100°) as defined by the
angle fo rmed between the bicycle seat tube appa­
ratus and a vertical line (fig. 2). Rotating the seat
to maintain a backrest perpendicular to the ground,
induced a systematic decrease in hip angle from
the 0 to 100° position. The body orienta tion (trunk
perpendi cular to the ground) was standardised as
was the mean knee and ankle angles, seat-to-pedal
distance (100% of greater trochanteric he ight), a nd
aerobic testing protocol. It was determined that for
total work output and maximal aerobic energy ex­
penditure, performance in the 75° seat tube angle
position (76.8° mean hip angle configuration) was
significantly greater (p < 0.01) than in the other
position except for the 50° seat tube angle (100°
mea n hip angle) [Too 1988, 1990]. Similar results
were found with anaerobic power and capacity, us­
ing the 30-second Wingate Anaerobic Cycling test
with a resistance of 85 g/ kg bodyweight (5.0 J/
pedal/ rev/ kg BW). Cycling performance as meas­
ured by anaerobic power and capacity in the 75°
body position (seat tube angle) was significantly
greater than all the other positions (p < 0.0 I), ex­
cept for the 50° position (Too 1989a). Hull and
Gonzalez ('I 990} also fO ll d a seat tube angle of76°
minim is d the j oint moment cost fun ction of cyl­
ing when det rmi ned with an optimisation model
and that the optimal seat tube angle decreased with
increased rider size.
Another investigation by Too (1 989b) examined
the effect of systematic manipulation of body ori­
entation on aerobic cycling perfo rmance while con­
troll ing for body position/configuration. Using a
seat tube angle of 7Y with the scat-backrest per­
pend icular to the ground, 10 male subj ects were
tested in eac h of 3 body orientations (60, 90 and
294
SPOilS M edicinC' 10 (5) 1990
sign ifica nt differenc s in anaerobic powe r a nd ca­
pacity would be found with changes in bod y ori­
entat ion is unknown . The 120' orientation would
allow the rider to push agai nst the backrest when
cycling whereas the 60° orientation would place the
legs in a more ad vantageo us orien ta tion with re­
gards to the line of gra vity. C urrentl y, a study is
in progress examining this.
3. Seat to Pedal Distance
3.1. Seat Height
Fig. 2. Body positions.
120°) as defi ned by the angle formed between the
seat backrest a nd a ho rizontal line paraliel to the
ground (fig. 3). T o o bta in the 60 and 120° orien­
tation, the entire cycling a pparatus was rotated 60°
forward a nd backwards, respectively. It was de ter­
mined there were no ignificant differences in max­
imal aerobic energy expenditu re and total work
output with changes in body orientation. W hether
The efli c tive ness of force production on a bi­
cycle is affected by man y fact ors. O ne of th ese fac­
tors is the sea l height. Alteration of the seat height
would not only alter joint angles but also muscle
lengths and muscle momen l arm lengths, thereby
changing the kinematics of cycling. T h is has b en
demonstrated USlI1g thigh-knee angle d iagrams from
a sim ula tion output with sca l heights at 36.4 and
38 inches (92.5 and 96.5cm), respectivel y (Nordee n
& Cavanagh 1976). Thi s, in tu rn, wou ld probably
change the force output of a m uscle. Whether the
resu lting force will be greater or lower wil l depend
upon the ml!lscle position in the tension-length
curve. The change in joint angle mayor may not
place thc musc'ie lever moment a rm system in a
more mechanicall y advantageous/ disadvan tageous
position to exert force (Titlow et al. 1986). T he re­
sultant muscle force and its effecti ve.ness will be
based upon the interaction of the position of the
muscle in the te nsion-length curve and the posit ion
in the mu scle lever m o ment arm system of the new
joint angle. T herefore, with cha nges in bod y posi­
tion and body orientatio n, there must be corre­
spondi ng changes in the seat to p dal d ista nce if
com pa rison rega rding cycling effectiveness in sim­
ila r body configurations are to be made.
T he optimal seat heigh t for a bicycle with an
upright seating posit jon was determi ned by T homas
(l967a.c) to be 109% of the medial aspect of the
inside leg from the floo r to the symphysis pubis.
T he seal height was measured fro m the pedal spin­
dle to the to p o f the seat along a stright line formed
by the cran k, seat tu bt' and seat post. T his meas­
urement was determ ined to be accurate with 80%
Factor Affecting Cycling Performance
of all individua l tested (T homas J967b) and mo t
efficient for tasks req uiring a naerobic work of high
intensi ty for short d ura tions (Hamley & Thom as
J967; T homas 1967c). An y other position greater
or I ss than th is valu was less efficient a nd meta­
bolicall y more costly. O n the other ha nd , Shennu m
and deVries (1976) found the most e ffic ient seat
heigh t for tasks req ui ri ng aerobic work to be 105
to 108% of the inside leg from the floor to the sym ­
Fig. 3. Body orientations.
295
ph ysis pubi . although they suggest the use of a
sadd le height of approximately 108 to 109% of
symphysis pubi -to-floor distance [based on their
oxygen consumption data with the data by Thomas
(I 967c) and Ha mley and Thomas (1 967) on powe r
output]. T he data by Shen num and deV ries ( 1976)
appears to be supported by Nordeen ( I 76) a nd
Nordeen-Sn de r (1 977), who indicated the most ef­
ficient seat height fo r aerobic work to be 107.10f0
296
and by G regor et al. (1981), who indicated that of
the 10 elite male cyclists investigated in his study,
the average saddle heigh t was 106% of pubic sym­
physis heigbt. It should be noted that the data re­
ported by Shenn um and deVries (1976), Nordeen
(1976) and Nordeen-Snyder (1977), were con­
verted to values which allowed for comparisons
with other investigations.
The investigation by Shennum and deVries
(1976) defined leg length as the measured distan ce
from the ischiu m to the floor. U sing a fully artic­
ulated skeleton in the erect position , Shennum and
deVries (1976) reported a nearly 5% lower value
with their ischium-to-floor method when com­
pared to the Thomas (1967a,b,c) symphysis pubis­
to-floor techniq ue. There, Shennum and de Vries
( 1976) indicated that to compare thei r data with
those of Thomas (1967c) and Hamley and Thomas
(1967), it was necessary to add approximately 5%
to thei r leg length measures. The investigation by
Nordeen-Snyder (1977) used scat heights of 95, 100,
and 105% of trochanteric leg length. Nordeen (1976)
indicated the calculated saddle height was divided
by the subject's symphysis pubis height to obtain
values which could be compared to those of Ham­
ley and Thomas (1967). Therefore, the 95 , 100 and
105% of trochanteric leg length (N ordeen-Snyder,
1977) corresponded to 101.7, 107.1, and 112.I%of
symphysis pubis height as calculated by Hamley
and Thomas (1 967).
The seat to pedal distance of 100% trochanteric
leg length which minimises oxygen consumption,
as reported by Nordeen (1976) and Nordeen-Sny­
der (1977) appear to be different from the tro­
chanteric leg length percentage of the Hodges study
(Borysewicz, 1985). Borysewicz (1985) stated that
Hodges, in April 1982 at the Olympic Training
Center, found that seat height which minimised
oxygen consumption was 96% of trochanteric leg
length . II male cyclists were tested on their own
bicycles at 10 different seat heights (ranging from
92% to 100% of trochanteric leg length). Borysew­
icz (1985) indicated that an ergometer-like device
was attached to each cyclists' bicycle and a hy­
draulic seat post constructed by H odges allowed
manipulation of the resistance and the seat height
Sporl.~
.'vfedicine 10 (5) 1990
duri ng each test session. T he test protocol requi red
each cyclist to complete two 45-m inute sessions at
80% of their maximum oxygen consumption. Dur­
ing each session, the cyclists' saddle was randomly
raised or lowered 5 to 6 times every 6 to 8 min u tes
to d ifferent trochanteric leg length percen tage .
Borysewicz (i 985) slated the minimal and m axi­
mal oxygen consumption values with the same
workload was found by Hodges to occu r at saddle
heights of 96 and 100% of trochanteric leg length,
respectively. Because the Hodges study, as re­
ported by Borysewicz (1985) does not appear to be
published, it is difficult to determine why the re are
differences in optimal percentages of trochanteric
leg length and what these differences are attributed
to when compared to the values reported by Nor­
deen-Snyder (1977). Similar results were found by
Hull and Gonzalez (I990) with an optimisation
model for cycling. For a cyclist of av rage height
(1.78m) and weight (72.5kg), Hull and Gonzalez
(1990) determined that the optimal seat height plus
crank arm length should be 97% of trochanteric leg
length to minimise the cycling cost function.
In a comparison of lower limb electro my­
ographic activity between 2 seat heights (lOS liS 95%
of pubic symphysis height) for national level male
cyclists, Despires (1974) reported no significant
differences in muscle activity. Similarly, Houtz and
Fischer (195 9) state that varying the height of the
bicycle seat from 2 1 inches (53cm) to 24 inches
(6Icm) does not affect, in general, the timing of
muscle activity; although the exercise is performed
with less effort at 24 inches. In using 2 specified
seat heights for all subjects, Houtz and Fischer
(1959) did not account for individual differences
in lower limb lengths. The optimal scat to pedal
distance for nonconventional human powered ve­
hicles is unknown .
3.2 Cra nk Arm Length
Changing the crank length, instead of the seat
height will also alter the seat-to-pedal distance. But,
there appear to be certain differences between the
2 methods. First, altering crank lengths will result
in greater torq ues being attained with longer cranks
Factors Affecting Cycling Performance
whereas raising the seat to obtain a greater seat-to­
pedal d istance will not. Secondly , there is decreas­
ing muscle tension with increasing crank lengths,
which would affect the amount of muscular fatigue
experienced over time. Finally, with increasing
crank lengths force patterns can change and de­
viate from the optimal pattern (lnbar et al. 1983).
T here appears to be a limitation regarding the
length of the crank arm. Sim pson (1979) states the
crank arm length is limited by the fact that the pe­
dal at the bottom of the arc must clear the ground
on turns. The pedal at its farthest forward point,
must not interfere with the turning of the front
wheel (the wheel must not hit the toe-cage). Other
considerations regarding the selection of a crank
length include: (a) the cyclists' leg length (i.e. the
reach of the leg on the downstroke, the angle of the
leg on the upstroke) ; (b) the type of terrain in­
volved and the gearing ratio selected; and (c) the
nature of the competition (longer cranks for hiB
climbs and shorter cranks for pursuits and sprints
where fast rotations are required).
From the available literature, the crank lengths
which have been investigated ranged from 3.1
inches (7.9cm) to 9.45 inches (24cm) [Goto et al
1976]. To maintain the same seat-to-pedal dis­
tances with different crank lengths, the seat-to-pe­
dal distance is elevated or lowered correspondingly
to the increase or decrease in crank length (Astrand
1953; lnbar et al. 1983). lnbar et al. (\ 983) state
seat heigh t variation will only affect the muscle
force application angle to the pe<;lals while crank
length alteration will simultaneously involve other
factors as well. Since the effects of these factors is
not believed to be parallel or even unidirectional,
the exact nature of the combined effect is difficult
to predetermine. For instance, a Scm deviation in
crank length from the optimum can produce a 1%
power output fall-off whereas a similar Scm change
from the optimal seat height can result in a 5 to
8% decrement in efficiency or power in both aero­
bic and anaerobic cycle ergometry (lnbar et al.
1983).
The most commonly used bicycle pedal crank
length is 6.5 inches (\ 6.5cm) [Dickinson 1929].
Whitt (1969) states that the optimum pedal crank
297
length appears to be approximately 6.5 inches
(\ 6.5cm) to 7 inches (\ 7.8cm). The use of long
cranks, such as those 9 inches long (22.9cm), re­
sults in inefficient muscle usage and is analogous
to cycling in a seat height that is too low. lnbar et
al. ( 1983) reported that the optimal crank length
for peak power and mean power in an all-out an­
aerobic test (30-second Wingate) was 16.6cm and
16.4cm, respectively. lnbar et al. (1983) state the
optimal crank lengths for shorter or taller individ­
uals (leg lengths of92 to 97cm and 100 to 107.2cm,
respectively) should vary from the sta ndard crank
length (l7.5cm) by km for approximately every
6.3cm difference in leg length. For aerobic work,
Carmichael (1981) indicate that the crank length
minimising oxygen consumption is dependent upon
the upper thigh length and determined by the equa­
tion :
Optimal crank length (m m ) =2.33 (u pper leg length
in em) + 55.8.
In an aerobic test involving 9 male competitive
cyclists tested at 75% of maximal oxygen con­
sumption with cranks 15,16,17,18, 19, and 20cm
in length, Carmichael (1981) reported optimal crank
length was correctly predicted by the upper leg
length with 80% accuracy. These results were lim­
ited to subjects with heights between 169.3 to
195.5cm, tota1lleg length between 84.0 to 102.9cm,
upper leg lengths between 41.0 to 50.8cm, and lower
leg lengths between 43.0 to 53.8cm. Depending on
the size of the cyclist, Hull and Gonzalez (1990),
found that a crank arm length of 14cm minimised
the cost function in cycling for a rider of average
anthropometry (height 1.78m, weight n.5kg).
However; with increasing size, the optimal crank
arm length will also increase.
In other studies, Goto et al. (1976) found that
oxygen con sumption and electromyographic activ­
ity increased only slightly for cranks 3.1 inches
(7.9cm) and 6.3 inches (l6cm) in length, whereas
marked increases were found for cranks 9.45 inches
(24cm) in length. Astrand (1953), using 16, 18, and
20cm crank length s, reported an energy output of
12.5 kcal/min when cycling at 20 km/h on a tread­
mill with a 2% slope. N o significant differences in
298
efficiency (as measured by oxygen con umption)
were found among the various crank lengths. Op­
timal crank lengths for boys 6, 8, and 10 years of
age were reported by Klim t and Voigt (1974) to be
14, 15 and 16cm , resp ctively. Whether similar re­
sults will be found with the same crank ann lengths
when tested in nonc nventional cycli ng positions
is unknown.
4. Factors Affecting Cycling Energy Expenditure There appears to be some optimal pedalling fre­
quency for different workloads which would min­
imise energy for some power output (Cavanagh &
Kram J985a,b). The number of investigations in­
volving manipulation of these variables are quite
large and varied. Some investigators have exam­
ined the effect of alterin g workload a nd power OUL­
put on energy expenditure while maintaining a
constant pedalling fr qucncy (Coast & Welch 1985;
Gaesser & Brooks 1975; Gollnick et al. 1974; Hag­
berg et al. 1978; Henry & DeMoor 1950; Hugh­
Jones 1947). Other investigators have examined the
effect of altering pedalling frequ ency on energy ex­
penditure while maintaining: (a) a constant resist­
ance (Benedict & Cathcart 191 3; Dickinson 1929;
Girandola & Henry 1976); (b) the frictiona l load,
while keeping the total work constant (Croisant
1975); or (c) the same power output by simultan­
eously changing the workload (Faria et al. 1982;
MoKay & Banister 1976; Michielli & Stricevic 1977;
Moffatt & Stamford 1978; Stamford 1973). Still
others have examined the effect of different pe­
dalling frequencies on energy expendit ure wllile
worki ng at a certain percentage of maxi mu m oxy­
gen uptake (Cafarelli 1978; G ueli & Shephard 1976;
Hagberg Giese, & Mullin 1975; Hagberg et a1. 198 1;
Jordan & Merrill 1979; Lollgen et al. 1980; Merrill
& White 1984; Patterson & Pear on 1983), altering
both the pedalli ng fr quency and power output
(Ban ister & Jackson 1967; Boning et al. 1984;
Croi san t 1979; Croisa nt & Boileau 1984; Hagberg
et al. 1975; Kn uttgen et al. 1971 ; Pugh j 974; Sea­
bury et aI. 1975. 1977), or manipulations with other
combinations of pedalling rates, workloads, and
Sports Medicine 10 (5) 1990
power outputs (Garry & Wishart 1931; Kro n 1983;
McCartney el al. 1983; PaIldol f & Noble 1973).
ManipUlations of the pedalling rate, fri ctional load,
power output, and/or t tal work accomplished can
affect the amount of energy expended for a given
cycling task.
4. 1 Workload, Power Output and Pedalling Rate The op timal pedalling rate to minimise energy
expendi ture and max:imise efficiency is believed by
many investigators to vary with the workload sel­
ected. Croisanl and Boilea u (1984) indicate there
is a significa nt int raction between workload and
pedalli ng freq uency; and with an increase in work­
load and power output, a n nl inear increase in the
optimal pedalling rate is required to minimi e en­
ergy ex.penditure. Croisant (1979) states the rela­
tion between workload and pedalling frequency is
fairly linear between lhe loads of 1 and 3kp for
rates of 20, 40, 60 and 80 rpm, but is more sharply
curvilinear above 3kp and below I kp. This is sup­
ported by Boni ng el al. (1984), who reported non­
linear relations with pedalling frequencies and
stated that the lowest oxygen uptake and the high­
est efficiency shifted to higher pedalling frequen­
cies with increasing workload. However, it appears
that increasing the pedalling freq uency without in­
creasing the workload may increase the relative en­
ergy expended rather than decrease it. It would also
appear that depending on the workload selected,
an increase in pedalling frequency accompanied by
a corresponding decrease in frictional resistance (to
mai ntain an eq uivalent power ou tpu t) will res ult
in: (a) a significant increase in oxygen consump­
tion at moderate power outputs [i.e. 800 kg· m/mi n
(I 31W)]; and (b) a significant decrease in oxygen
co nsumpt ion at high power o utp uts [i.e.
1800 kg • m/ min (294W)] (Fari a et al. 1982). T his
suggests a defmite interaction betwe n pedalling
freque ncy, power output, a nd energy expenditure,
and a most efficient p dalling rate for different
power outputs.
This was confirmed by Seabury et al. (1977),
who found that: (a) a most efficient pedalli ng rate
299
Factors Affecting Cycling Performance
exists for each power output studied; (b) the m ost
efficien t pedalling rate increases with power o ut­
put; (c) the increase in energy expendi tu re when
pedalling slower than optimal is greater at high
power outpu ts than at lower power outputs; and
(d) tbe increase in energy expend iture when pe­
dalling faste r tha n opti ma l is greater at low power
outputs than a l high power outputs. Con trary to
the da ta reported by Seabury et a l. ( J 977), Hagberg
e1 al. (198 l) stated that if e cyclist is un ure of
his opti mal peda lli ng rate, pedal!i ng speed that is
less than the opti mal level is more effi cient than
one that is above. It is unknown whether these d if­
ferences were attributed to the use of a different
subject population , the test protocol, or both be­
cause competitive cyclists were used by Hagberg et
al. ( 198 1) and testing invo lved riding their own
racing bicycles on a treadmil l. Finally, H ul l and
Gonzalez (1990) determi ned, with an opt imisation
modeJ, the optimal pedall ing rate to be l IS rpm
at a constant ave rage power of 200W. But. the op­
timal pedall ing rate was stated to decrease as the
rider's size increased.
It is di fficult to determine whether optimal pe­
dall ing frequen cies reported in the literatu re for
difte rent workloads and power outputs are also ap­
propriate for ditTerent bod y positions, configura­
tions, a nd orientations in nonconventional bicy­
cles. Based on the available informati on, it is logical
to assume some optima! pedalli ng frequencies do
exist for d ifferen t power outp uts which would
maxim ise efficiency and minim ise energy expend­
iru re for both subma ximal and maxi mal workloads
in nonstanda rd cycli ng positions.
5. Conclusion
There are a large nu mb r offacto rs affecting cy­
cling performance and a gap still exists between
cycling research in the various disciplines. To bridge
this gap req uires cooperation and interd isciplinary
research between the engineers and ki nesiologists.
To maximi se and/or opti mise cycling performa nce
req uires a defi nition of performa nce, the criterion
for perfo rma nce and the constrai nts im posed upon
it. If the criterion is development of an 'ultim ate'
h uman-powered vehicle to establish un prece­
dented speed and/ or distance records on land, air,
and/or sea, then in fo rmat ion must be obtained re­
gardi ng the interaction of en viro nmental fac tors
with mechanical and hu man factors. T hi s would
involve the design an d development of a human­
powered vehicle to not only account for aerodyn­
amic and/or hydrodynamic drag, but also to seat
and position an ind ividual in an orientation and
configuration that would optimise interaction of the
various neurological, biomechanical a nd physio­
logical variables related to power. work. energy, and
efficiency. Furt her interdiscipli nary research needs
to be underta ken before fi nal solutions to these
issues can be obtained.
References
ASlrand po. Stud y of bicycle modificalions using a motor driven
treadmill-bicyclc ergometer. Arbeitsphysiologie 15: 23-32. 1953
Ast ra nd PO. Rodahl K. T extbook of work physiology, 2nd cd.,
M cGraw-HilI. N ew York. 1977
Banister EW, Jackson RC. The effect of speed and load changes
on oxygen intakc for equivalent powe r outputs during bicycle
crgometry. Internationale Zeitschrift fur Angewandte Physiol­
ogic Einschliesslich 24: 284-290, 1967
Baz A. Optimization of man's energy during underwater paddle
propulsion. Ergonomics 22: 1105-1114, 1979
Be nedict FG, Calhcart EP. Muscular work: a metabolic study with
special reference to the cfficiency o f the human bod y as a ma­
chine, Cambridge University Press. New York, 191 3
Be vcgard S. Frcyschl1ss U. Slrandcll T. C irculatory adaptation to.
arm and leg exercise in supinc and sitting position. Journal of
Applied P hysiology 21: 37-46, 1966
Bevegard S, Holmgren A, Jonsson B. T he effect of body position
on the circulation al res I and during cxercise, with special ref­
ercnce to the influence on the stroke volume. Acta Physiolo­
gica Scandinavica 49: 279-298, 1960
Bcvegard S. Holmgre n A, Jonsson B. Circulatory studies in well
trained alhletes at re st and during hcavy exercise, wi,th special
reference to stroke volume and the influence of body position.
Acta P hysiologica Scandinavica 57: 26-50, 1963
Bishop JM, Donald KW, Taylor SH, Wormald PN. Effect of su­
pine leg exercise on the splanchnic A-V oxygen difference in
normal subjects. Journal of Physiology 133: 9P, 1956
Boloorchi F, Hull M L. M ea s urement of rider induced loads dur­
ing simulated bicycli ng. I n T crauds & Barham (Eds) Biome­
chanics in sports II. pp. 178-198. Academic Press. San Diego,
1985
Boning D. Gonen Y. M aassen N. Relationship between work load,
pedal frequency, and ph ysical fitness. International Journal of
SPOri S M edicine 5 (2): 92-97, 1984
Boor P. T hose magnificent machines. A merican Wheel men 17
(5): 22-23. 198 I
Borysewi cz E. Bicycle road racing. Velo-ne w Corporation, Bral­
tleba ro, Ve rmont, 1985
Brooke JO, Hoare J. Rose nrot P. T riggs R. C omputerizcd system
for measurement of force cxerlcd within each pedal revolution
during cycling. Physiology and Behavior 26 (I): 139-143,1981
300
Burke ER . Sc ience of cycling, Human Kinetics Publishe rs. C ham­ paign. 1986 Cafarclli E. EtTcct of contraction frequency o n e tTo rt sensa ti o n during cycling at a constant res istance. Mcdic ine and Science in Sports 10 (4): 270-275 , 1978 Carmicllael J'KS. Thc e ffect of eranklength on oxygcn consump­ tion when cycling at a co nstant work rate, U npublished mas­ ter' s thes is, Pennsylvania State University, 1981 Cava nagh PR , Kram R. Thc clliciency of human mo veme nt - a
statement of the problem. Mcdicine and Scicnce in Sports and
Exe rcise 17: 304-308, 1985a
Cava nagh PR, Kram R. Mechanical and muscular factors '!fTee t­
ing the efficiency of human mo vc mcnt. Medicine a nd Scie nce
in Sports and EXC1"cise 17: 326-331. 1985b
Coast JR, Welch HG. Linear increase in optimal pedal ratc with increased power output in cycle ergometry. European Journal of Applied Physiology 53 (4): 339-342, 1985 Convertino VA, Goldwater OJ, Sandlcr H. Oxygen uptakc ki­
netics of constant-load work: uprigh t vs. supine exercise. A via­ tion Space Environmental Medicine 55 (6): 501-506, 1984 Cornelius CJ, Seireg AA. Optimum human power. Soma I (I):
21-29.1986
Croisant PT. Efficiency of bicycle ergometer work at selected rates of lim b movement for college women. Unpublished master's thesis. U niversity of Illinois at Urbana-Champaign. 1975 C roisant PT. Effect of pedal rate. brake load, and workratc on metabolic work and recovery. Doctoral dissertation, Univer­ sity of [Ilinois at Urbana-Champaign. 1979 Cro isa nt PT. Boilcau RA. EtTect of pedal rate. brake load and power on me labolic responses 10 bicycle ergomelcr work. Er­
gonomics 27: 691-700. 1984 C umming GR.. Sirnke volume dUT'ing recovery from supine bi­ cycle exercise. Jou rnal of Applied Ph ysiology 32: 575-578, 1972 Daly DJ, Cavanagh PR o Asymmelrv in bicycle ergometer pe­
dalling. Medi cine a nd Science in Sports 8: 204-208, 1976 Davis RR, Hull ML. Measuremenl of pedal loading in bicycling:
II. A nal ysis and resulis. Journal of Biomechanics 14 (12): 85 7­
872. 198 1 Davis RR . Hull ML. Biomcchanics of bi cycling. In Terauds (Ed.) Biomechanics in sports. pp. 113-133, Acadcmic Press, San Diego, 1982 Dcspires M . An elec lrom yographic sludy o f compeliti ve road cy­
cling condili o ns simulaled o n a treadmill. In Nelson & Mo­ rehouse (Ed s) Biomechanics IV , pp. 349-355, Uni versity Park Press, Baliimore, 1974 Diaz RJ , Hage n RD, Wright JE, Horvath SM. Maximal sub­ ma ximal exercise in diffe re nt positions. Medic ine and Science in Sports 10 (3): 2 14-2 17. 1978 Dickhuth HH , Simon G . He iss HW. Lehman M , W ybitul K. Co mpa rati ve cc hoca rdiographic exa minations in silling and supin e position al rest and during d yna mic exc rci se. Interna­ ti ona l Jo urnal of Sports Medicine 2 ( 3): 178- 182, 1981 Dicki n son S. T he e llic ie ncy of bicycle-pedaling, as affeeled by speed and load. Jo urnal o f Physiology 67: 242-255 , 1929 Dill DB, Seed J C, Marzulli FN . En erg y expen diture in bicycle riding, Journal of Applied Physiology 7: 320-3 24, 1954 Drela M, Langfo rd JS. Human-powered fligh!. Scientific Ameri­ can 253 (5): 144-151,1985 Eke lund LG. Circulalory a nd respiratory adaplalion during pro­ lon ged exercise in Ihe supine posilion. Ac ta Ph ys lologica Scan­ dinavica 68: 382-396, 1966 Eke lund LG. C ircu lalO ry and respiralory adaplalion during pro­
longed exercise of moderale inte nsilY in the silling posilion.
ACla P hy sio logi ca Scandinaviea 69: 327-340. 1967a
Ekelund LG . Ci rcu la lory a nd respiralory a daplalion during pro­
longed cxercises. ACla Physiologiea Scandinavica 70 (Suppl.
292): 1-38, 1967b
Eri cso n MO. Nise ll R. Effi c ie ncy of pedal forces during e rgometer
Sports Medicine 10 (5) 1990
cycl ing. Interna tional Jo urnal of Spo rls Medicine 9: 118-122, 1988 Eri cso n MO, Nisell R, Ne m e lh G. Joint mOlio ns of the lower limb d uring e rgo meler cycling. Journal o f Orthopaedic and Spons Physical The rap y 26 ( I) : 52-54. 1988 Faria IE, Cava nag h PRo The ph ys io logy and biomechanics of cy­ c ling . .J o hn Wiley & So ns, New York, 19 78 Faria 1, Di x C, Frazer C. Effec t of body posilion during cycling on hea n rate, pulmonary ven tilalion , oxygen uplake and work Oulpul. J ournal of Sports Med ici ne and Physical Fitness 18 (I): 49-5 6, 1978 Faria I, Sjojaard G , Bon d e-Pe tersen F. Oxygen cos I during dif­ ferenl pedalling spceds for conSlanl power outpu!. Journal of Sports Medi ci ne a nd Physical Fitness 22 (3): 295-299, 1982 Gaessc r G A, Brooks GA. Mu scular e ffi ciency during sleady-rale exe rc ise: e ffects of speed and work rale. Journal of Applied Physiology 38: 113 2- 1139, 19 75 GalbO H , Pauley PE. Ca rdi ac fun c lion during rest and supine cyL'ling examined wilh a new noninvasive lechnique (CEO). Journal o f Appli ed Physio'iogy 36: 113-ll 7, 1974 Gany RC, Wishart G M . Oil Ihe ex islence of a mOSI efficienl speed in bicycle pedalling, and Ihe problem of d e lermining human mu sc ular e ffi c ie ncy. J o urna l of Physiology 72: 426-437, 1931 Girandola RN, Henry FM . Individual diffe re nces in hea vy work endurance al 60, 70 and 84 rpm e rgo meier pedal specd. Re­
search Quarterly 47 (4): 647-656, 1976 Gollnick PO, Piehl K. Sallin B. Seleclive glycogen d e pl e lion pa l­
lern in human muscle fiber s afier exercise of varying inlensilY and al varying pedalling ra les. J ourna l of Physiology 241: 45­
57, 1974 GolO S. Toyoshi ma S, Hoshikawa T. Siudy of Ihe inlegraled B 1G leg muscles during pedaling of various loads. frequency, and equivalenl power. [n Komi (Ed.) Bi o mcc han ics V-A , pp. 246­
252. Un iv ersi ty Park Press, Ballimore, 1976 Granalh A, Jonsson B. Sirandell T. Siudies on Ihe eellira l ci r­
culation al reSI and during exercise in th e supi nc and si lling bod y posilion in o ld men : preliminary report. ACla Medi ca Scandinavica 169: 125-1 26, 1961 Granalh A. Jonsso n B, Sirandell T. C irc ulatio n in hca lih y o ld m e n. sludi ed b y rig!ll hearl ca lheleri za lion at reSI a nd durin g exercise in Ihe supine silting position . Ac ta Medica Scandi­ na vica 176: 425-446, 1964 Gregor RJ. A bio mechan ical a nal ysis o f lower limb aClio n during cycl ing at fo ur differe nt load s. Doc toral d isscrtation , Pennsyl­ va nia Statc U ni ve rsity, 1976 Gregor RJ , Cavanagh PRo A biomechanical analysis of lower limb action during cycling at four ditTc ren t load s. Abst rac t. Medi­ ci ne and Science in Spo rts 8 (I): 57, 1976 Gregor RJ, Cavanagh PR , Lafo rlune M. Knee fl exo r m om enlS during propulsion in cyc lin g - a e realive solulion 10 Lombard's paradox. Journ a l of Biomec hani cs 18 (5): 307-316, 1985 Gregor RJ , Green D, Garhammer JJ . A n eleclro m yographic an ­
al ysis of selected muscle aetivilY in elile co mpe tili ve eyc lisls. [n Morec ki el al. (Eds) Bi omechanics VII-B, pp. 537-541, Uni­
versity Park Press. Ba llimore, 1981 Gross AC. Kyl e CR, Malewicki OJ. The ae rodynamics o f human­ powered land vehicles. Scientific American 249 (6): 142-15 2, 1983 Gueli 0, Shephard RJ. Pedal frequency in bicycle ergometry. Ca­ nadian Journal of Applied Sports Sciences I': 137-141, 197 6 Gullbring B. Holmgren A. Sjoslrand T, Sirandell T. Th e effect of blood volume varialions on Ihe pulse rale in supine and up­ righl posilions and during exercise. Acta Physiologiea Scan­ dinavica 50: 62-71, 1960 Hagberg JM, Giese MD, Mullin JP. Effeci of differenl gear ralios on Ihe melabolic responses of eompelitive cyclisls 10 eonSlanl load sicady Slate work. Medicine and Science in Sporls 7: 74, 1975 Hagberg JM, Giese MD, Schnieder RB. Comparison oflhrec pro­
Factors Affecting Cycling Performance
cedures for measuring V02max of competitive cyclists. Euro­
pean Journal of Applied Physiology 39: 47-52. 1978 Hagberg JM. M ullin JP, Giese M D, Spitznagel E. Effe ct of pe­
dalling rate on submaximal exercise responses of compctitive
cyclists. Journal of Appl ied Physiology 51: 447-451,1981
Hamley EJ. T homas V. Physiological and postural factors in the calibration of bicycle ergometer. Journal of Physiology 19 I: 55­
57P,1967 Henry fJ, DcMoor J. Metabolic cmcicncy of exercise in relation
to work load at constant speed. Journal of Applied Physiology
2: 481-487, 1950 Hoes MJAJM. Binkhorst RA. Smeekcs-Kuyl AEMC'. Vissers ACA. Measurement of forces cxerted on pedal and crank during work on a bin'cle ergometcr at different loads. Internationale Zcit­ sehrift fur Angewandte Physiologic Einselliesslick Arbcitsphy­ siologie 26: 33-42. 1968 Holmgren A, Jonsson B. Sjostrand T Circulatory data in normal subjccts at rest and during cxercise in recumbent position, with special refercnce to the strokc volumc at different work in­
tensities. Acta Physiologica Scandinavica 49: 343-363, 1960 Holmgren A. Mossleldt F, Sjostrand T. Strom G. EITect of train­ ing on work capacity, total hemoglobin, blood volume, hcart volume and pulse ratc in recumbent and upright post ions. Aeta Physiologica Scandinavica 50: 72-83, 1960 Houtz SJ, Fischer FJ. An analysis of muscle action and joint cx­
cursion during excrcise on a stationary bicycle. Journal of Bone and Joint Surgery 41A (I): 123-131, 1959 Hugh-Jones P. The effect of scat position on thc cfTiciency of bic ycle pedalin g. Journal of Physiology 106: 186-193, 1947 Hull ML. Davis RR . Measurement of pedal loading in bicycling: L Instrumentation. Journal of Biomcchanics 14 (12): 843-855. 1981 Hull ML Gonzalez HK. Bivariate optimitation of pedalling rate and crank arm length in cycling. Journal of Biomechanics 21 (10): 839-849, 1988 Hull ML, Gonzalez HK. Multivariable optimization of cvcling biomechanics. [n Kreighbaum et al. (Eds) Biomcchanics in Sports VI, pp. 15-41, Montana State University, Boteman. Montana. 1990 Hull ML, Gonzalez HK. Redfield R. Optimization of pedaling rate in cycling using a muscle stress-based objective function. Internati o nal Journal of Sport Biomechanics 4: 1-20. 1988 Hull ML, Jorge M. A method for biomcchanical analysis of bi­
cycle pedall ing. Journal o f Biomechanics 18 (9): 631-644, 1985 Inbar 0 , Dotan R. Trousil T , Dvir Z. The elTcct of bicycle crank­ length variation upon power performance. Ergonomics 26 (12): I 139-1 146. 1983 Jorge M. Hull ML Biomechanics of bicycle pedalling. In Terauds et aL (Eds) Sports biomechanics, pp. 233-246. Academic Pub­ lishers, California. 1984 Jordan L, Mcrrill EG. Relative efliciency as a function of pe­
dalling ra te for racing cyclists. Journal of Physiology 296: 49P­
59P, 1979 Kamon E, Mett KF. Pandolf EG. Climbing and cycling with ad­ ditional weights on the extremities. Journal of Applied Phys­ iology 35: 367-370. 1973 Kirshne r D . Aerodynamics vs. weight: quanti fying the trade-off. Bike Tech 4 (I): 5-9, 1985 Klimt F, Voigt GB. Studies for the standardisations of the pedal frequency and the crank length at the work on the bicycle­
ergometer in children between 6 and 10 years of age. European Journal of Applied Physiology 33 (4): 315-326. 1974 Knultgen HG . Bonde-Petersen 18. Klausen K. Oxygen uptake and heart rate responses to exe ..cise performed with concentric and eccentric muscle contractions. Medicine and Science in Sports 3: 1-5. 1971 Kroon H . T he optimum pedaling rate. Bike Tech 2: 1-5,1983
Kubicek F, G aul G. Comparison of supine and silting body po­
sition during a triangular exercise test. L Experiences in health
30l
subjects. European Journal of Applied Physiology 36 (4): 275­
283, 1977 Kunstlinger U. Ludwig HG. Stcgemann J. Force kinetics and oxy­
gen consumption during bicycle ergometer work in racing cycl­
ists and reference-group. International Journal of Sports Med­ ic ine 5: 118-119, 1984 Ky le CR . The aerodynamics of man powcrcd land vehicles. Pro­ ceeding of the Scminar on Planning, Design, and Implemen­ tation of Bicycle Pedestrian Facilities, pp. 312-326, San Di ego, California. 1974 Kyle CR. Aerodynamics the key to high speeds. Cycling 4693 (8): 20-21,1981 K yle CR. Go with the flow: aerodynamics and cycling. Bicycling 23 (4): 59-60. 62, 64-66. 1982 Kyle CR. Caiozzo VJ. Expcrimcnts in human ergometry as ap­ plied to the design of human powered vehicles. International Journa l of Sports Biomechanics 2: 6-19. 1986 Kyle CR. Crawford C , N adeau D . f actors affecting th e speed of a bicycle. CS ULB Enginecring Re port No. 73-1. California State University, Long Beach. 1973 Kyle CR, Crawford C, Nadeau D. What affects bicycle spced. Part L Bicycling 5 (7): 22·24, 1974 Kyle CR, Edelman WE , Mah powered vehicle dcsign criteria. In Sachs (Ed.) Proceed ings of the Third [nternational Conference of Vehicle System Dynamics, pp. 20-30, Swets & Zeitlinger, Amsterdam, 1975 Lafortune MA, Cavanagh PR. Force cffectiveness during cycling. Abstract. Medicine and Science in Sports and Exercise 12 (2): 95, 1980 Lafortune M A, Cavanagh PR. Eflectiveness and efficiency during bicycle riding. In Matsui & Kobayashi (Eds) Biomechanics VII­
B, pp. 928-936, Human Kinetics Publisher, Champaign. 1983 Lafortune MA, Cavanagh PRo Valiant GA, Burke ER. A study of the riding mechanics of elite cyclisls. Abstract. Medicine and Science in Sports and Excrcise 15 (2): 113, 1983 Lollge n H. Graham T, Sjogaard G . Muscle metabolites, force, and perceived cxertion bicycling a t varying pedal rates. Medicine and Sc icncc in Sports and Exercise 12 (5): 345-351, 1980 Malewickl DJ. Aerodynamics: who will win the DuPont Prize') Drag vs power at 65 mi/hr. Bike Tech 3 (5): 1-8, 1984 Martin S. The annual assault on human powered speed records. Bike World 8: 34-37, 1979 McCartney N . Heigenhauser GJR. Sargent AJ. Jone s NL A con­ stant-velocity cycle ergometer for the study of dynamic muscle function. Journal of Applied Physiology 55: 212-217, 1983 McKay GA. Banister EW. A comparison of maximum oxygen uptake d etermination by bicycle ergometry at various pedall­ ing frequencies and by treadmill running at various specds. European Journal of Applied Physiology 35: 191-200. 1976 ME Staff Report. Human-powered flight. Mechanical Engineering 106 (9): 46-55. 1984 Merrill EG. White JA. Physiological cmciency of constant power output at varying pedal rates. Journal of Sports Sciences 2: 25­
34,1984 Me tz LD, Moeinzadeh MH, White LR. Leg motion during stand­ ard and supine recumbent bicycle pedalling. Part II: Biome­ chanical observations and results. Journal of Biomechanics, in press, 1990 Metz LD. Moeinzadeh MH. White LR, Groppel JL Biomeehan­ ical aspects of supine recumbent bicycles. In Adrian & Deutsch (Eds) Biomechanics: the 1984 Olympic Scientific Congress proceedings, pp. 289-295, Microfilm Publications, University of Orcgon, Eugene. Oregon, 1986 Michielli DW, Stricevic M. Various pedaling frequencies at equivalent power output s: effect on heart rate response. New York State Journal of Medicine 77: 744-746, 1977 Moffatt RJ, Stamford BA. Effects of pedalling rate changes on
maximal oxygen uptake and perceived effort during bicycle
302
ergometer work. Medicine and Science in Sports 10: 27-31,
1978
Montgomery S, Titlow LW. John son DJ. Estimates of maximal
oxygen consumption from a stand-up bicycl e test. 10urnal of
Sport M edicine and Physical Fitness 18: 271-276, 1978
Nonwciler T. The air resistance of racing cycl ist, Report 106, The
College of Aeronautics, Crallfte ld, En gland, 1956
Nonweiler T. Power output o f ra c ing cycl ists. Engineering 183
(4757): 586, 1957
N ord~en KS. The effect of bicycle sea t height variation upon oxy­
gen con sumption and both experimental and simulated lower
limb kinematics. Unpublished master's thesis, Pennsylvania
State niversity, 1976
.
Nordce n KS , Cavanagh PRo S imulation of lower limb kinematics
during cycling. In Komi (Ed .) Biomechanics V-B, pp. 26-33,
Univcrsity Park P ress, Baltimore, 1976
Nordccn-Snyd':r KS. The e ffect of bicycle scat he ight variation
upon oxygen co n sumption and lowe r limb kinematics. Med ­
icine. and Scien ce in Sports 9: 11 3-117, 1977
Pandolf K B, N Oble 81. The eflect of pedaling speed and resist­
ance chan ges on perceived e, ert lO n fo r equivalent power out­
puts on th e bicycle ergometer. Medicine and Science in S ports
5: 132-136, 1973
Palterson R P, Pearson lI.. Thc influence of flywe ight and pe­
dalling frequency on thc biomechanics and physiological re­
sponses to bicycle exercise. Ergonomics 26: 659-668 . 1983
Pugh LGC ' The relation of oxygen intake and speed in com­
pe ti tion cycl tng and comparativ e observations on the bieyclc
ergome ter. 10urnal of Physiology 241: 795-808, 1974
Redfi e.ld R. Hull ML. 10int moments and pedalling rates in bi­
cycling. In l e muds et al. (Eds) Spons biomechanics, pp. 247­
258, Acad e m ic P re$S, San Dicgo, 1984
Redfield R. Hu ll. M L. On the r~lation between ioint moments
a nd pedalling rates at constant power in bicycling. 10urnal of
Biomechanics 19 (4): 317-329. 1986a
Redfi e ld R, Hull ML. P rediction of pedal rorccs in bicycling using
optimi/ati o n met hods, Journal of Biom echanics 19 (7): 523­
540. 1986b
Reeves .I T , G ro ve r R F, Filley G F. Blount G1. Circulatory changes
in man during mild supine exe rcise. 10urnal of Applied Phys­
iology 16: 279-282, 1961
Sargent Aj, Charters A, Davie s CTM , Reeves ES. Measurement
of force s a pplied and work pcrform~d in pedalling a stationa l)'
bicycl e ergome ter. Ergonomics 21: 49-53. 1978
Sarge nt AJ, Davie . c- r M . Forces a pplied to cranks of a bicycle
ergome ter during one- and two-leg cycling. Journal of Applied
Physiology 4 2: 514-518, 1977
Seabu ry 11, Adam s W C, Ram sey MR . The Influence of pcdalling
rate and power ou tput o n e nc rgv expenditure during bicycle
crgol11etry. In Adams (Ed .) S(udles of metabolic energy ex­
penditure in bicycling, Report N o. 75-2, Civil Engineering De­
partment. University of California, Davis, 1975
Scabury 11, Adams WC, Ramsey M R. Influence of pedalling rate
and powe r output on energy expenditure during bicycle er­
gometr)' . Ergonomics 20: 491-498, 1977
Sports Medicine 10 (5) 1990
Shennum PL. deVries ri A. The effect of saddle height on oxygen
consumption durin g bicyclc crgomcter work. Mcdicinc and
Science in S ports 8: 119-121. 1976
Sim pson 1. Pro per crank arm lengths: resolution of thc rcvolu­
tions. Bi ke World 8 (5): 29-31, 1979
Sode n PO , Adeye fa BA. Forces applied to a bicycle durin g normal
cyc lin g. International Spons Sciences I (9): 738-739 , 1979a
Soden PD, Adeycfa S A. Forces applied to a bicycle during normal
cycling. 10urnal of Biomcehanics 12: 527-541, 1979b
S tamford BA. Perce ptual and physiological responses to equiva­
le nt power outputs performed on u bicycle ergometcr at vary­
ing pedalling rates. Doctoral dissertation, University of i'ills­
burgh, 1973
Stenberg 1, Astrand PO, Ekblom fl, Royce .I, Saltin S. Hemo­
dynamic responsc to work wlth dlffcre~t muscle groups, sitting
and suplnc. Journal of Applied Physiology 22: 61-70, 1967
Thoma s V. Saddle heigh!. Cycling 7: 24 , 1967a
Thomas y , Saddle height - conflicting VICWS. CyCling 4: 17, 1967b
Thomas V. Scic n t ifie selling of saddle posi tion. American Cycli ng
6 (4): 12- 13, 1967c
Timmons DR. The dICct of supine and upright position s o n the
hemodynamic and mctabolic performan ce of bicycle exercise.
UnpublIShed mas lC ~-S thesis, University o f W isconsin, La­
Crosse, 1981
Titlow LW. Ishee JH, Anders A. Effects of knee angle on sub­
maximal bicyclc crgometry. Journal of Sports Medicine and
Physical Fitness 26 (I): 52-54, 1986
Too D. The effcct of bod y position, configuration, and orienta­
tion on cycling performance. Doctoral disscrtation. University
of Ilinois at Urbana-Champaign, 1988
Too D. The effect of body position/configurat ion on anacrohic
power and capacity of' cycling. Abstract. Med icine and Science
in Sports and Exercise 21 (2) (Suppl.): 8 79, 1989a
Too D. The effect of bod y o rientation on cycling performance.
In Morrison (Ed.) Proceed ings of the V il th Intemational Sym­
posium of the Society of Bio mechanics in Sports, pp. 53-60,
Footscray Institute of Technology, Victori a. Australia, 1989b
roo D. The dIcet of body configuration on cycl in g performance.
In Kreighbaum ct ,,1. (led s) Biomechanics in S ports VI, pp. 51­
58, Montana State Unive rsity, Bozeman, Montana, 1990
Whill FR. Crank length and pcdalling efficiency. Cycling Touring
(Dec-Jan): 12, 1969
W hitl FR. A note on the estimation of the e nergy expcnditure of
sporting cyclists. Ergonomics 14: 419-424, 1971
W hill FR , Wilson Du. Bicycling science, 2nd ed., MIT Press,
Cambridge, 1982
W ilson SS. Bicycle technology. Scientific Ame rican 228 (3): 81­
91, 19 73
Correspondence and reprin ts: Dr Dal1 III , Too. Department of
Health, Physical Education and Recreation, California State Uni­
ve rsity Fullerton, 800 N. State College, Fullerton, CA 92634-4080,
USA.