Joint Kinetics Of Accelerated Running
Daniel J.
1Department
of Kinesiology,
1
Schuster ,
Shane M.
2Department
1
Rabideau ,
of Physical Therapy,
Introduction
Patrick
1
Rider ,
3Department
John
2
Willson ,
Anthony S.
3
Kulas
and Paul
1
DeVita
of Health and Promotion, East Carolina University, Greenville, North Carolina
Methods
Running biomechanics are well established in terms of ground
reaction forces, joint torques, and joint powers as is the direct
relationship between these variables and running speed. Many
studies have investigated the effects of these variables when running
velocity was increased in constant state increments (Arampatzis et
al, 1999; Belli et al, 2002; Schache et al, 2011, Dorn et al, 2012).
Running velocity in an athletic contest is rarely held constant.
Athletes go through periods of acceleration and it is these periods
that are less investigated. Van Caekenberghe et al (2013) performed
one of the few research studies investigating the acceleration period
of running. The results showed that there was no increase in the
joint torques at the hip, knee, and ankle by the participants during the
acceleration period of the trial on the instrumented treadmill.
Figure 4:
A2 Mean Peak Hip Joint
Torques
6 of 20 planned participants were analyzed on an instrumented treadmill
while accelerating at 0.40 ms-2 (A1) and 0.80 ms-2 (A2) from the initial to
final velocities. Inverse dynamics were used to determine lower limb joint
torques and powers using ground reaction forces and kinematic data
collected by 3D motion capture. Correlation and regression analyses were
used to identify the relationships between mean, maximum hip, knee, and
ankle torques and step number during the acceleration phase.
Figure 5:
A2 Mean Peak Knee Joint
Torques
Hypothesis and Purpose Statement
It was hypothesized that that there will be an increase in the
magnitude of the GRFs and joint torques and powers with each
step during accelerated running. The purpose of this study was
to quantify lower extremity joint torques and powers during
constant speed running and during running while accelerating at
two rates of acceleration between a baseline velocity of 2.50 ms-1
to a maximal velocity of 6.00 ms-1. Only torques are presented here.
Figure 6:
A2 Mean Peak Ankle Joint
Torques
Figure 7. Participant preparation and testing and V3D analysis.
Results
Figure1:
A1 Mean Peak Hip Joint
Torques
Results
Maximum joint torques at hip, knee, and ankle had correlations of
r=0.979, 0.699, and 0.948 respectively with step number in A1 (all
p<.05). Maximum joint torques at hip, knee, and ankle had correlations
of r=0.903, -0.028, and 0.921 respectively with step number in A2 with
only hip and ankle increasing significantly (p<.05) during accelerated
running. Table 1 below presents these values along with the initial and
final constant state velocities. The figures show the mean peak joint
torques for the hip, knee and ankle in each condition. Increases through
the acceleration period are evident at the hip and ankle.
Figure 2:
A1 Mean Peak Knee Joint
Torques
(6)
Pre
Accel
Figure 3:
A1 Mean Peak Ankle Joint
Torques
References
2. Belli A, Kyrolainen H, Komi PV. Moment and power of lower limb joints in running. International Journal of Sports
Medicine. 2002;23(2):136-141.
A2
3. Dorn TW, Schache AG, Pandy MG. Muscular strategy shift in human running: Dependence of running speed on hip
and ankle muscle performance. J Exp Biol. 2012;215(11):1944-1956. doi: 10.1242/jeb.064527.
Post
Accel
Pre
Accel
Accel
-0.012 0.979* -0.154
0.381
0.903* -0.154
Knee
0.317
0.699*
0.317
-0.416
-0.028 0.598*
Ankle
0.266
0.948*
0.527
0.258
0.921* -0.109
Hip
Accel
In contrast to a previous report, our data suggest that hip and ankle
torques do increase during accelerated running on a step by step
basis. Knee torque results need further study but may be directly
related to acceleration step number albeit not as strongly as hip and
ankle torques.
1. Arampatzis A, Bruggemann G, Metzler V. The effect of speed on leg stiffness and joint kinetics in human running. J
Biomech. 1999;32(12):1349-1353. doi: 10.1016/S0021-9290(99)00133-5.
Table 1: Step Number Correlations
A1
Conclusion
Post
Accel
4. Schache AG, Blanch PD, Dorn TW, Brown NAT, Rosemond D, Pandy MG. Effect of running speed on lower limb joint
kinetics. Med Sci Sports Exerc. 2011;43(7):1260-1271. doi: 10.1249/MSS.0b013e3182084929.
5. Van Caekenberghe I, Segers V, Aerts P, Willems P, De Clercq D. Joint kinematics and kinetics of overground
accelerated running versus running on an accelerated treadmill. Journal of the Royal Society Interface.
2013;10(84):20130222. doi: 10.1098/rsif.2013.0222.
PROTOCOL VIDEO
V3D MODEL
PROTOCOL VIDEO
V3D MODEL