Economic consequences when sport
research is premised on the “explanatory
power” of popular theories: The case of the
‘Free Ride Hypothesis’ for developing
countries and African females
Presenter: Prof. Simeon Davies
Dept of Sport Management,
Cape Peninsula University of Technology,
Cape Town, South Africa: daviess@cput.ac.za
SASReCon 2012
November 30 – December 1 2012
University of Pretoria)
Preamble and the National
Sport Plan
• This presentation seeks to highlight some
guiding research principles for the NSP
• Firstly that we should be wary of inductive
research designs
• Secondly to integrate more critical economic
assessments in our research
• And thirdly to avoid succumbing to arguments
premised on cultural relativism that result in the
continued marginalization and exploitation of
vulnerable people.
Introduction
• This presentation focuses on a
comprehensive research project by two
sport research departments from the Cape
Peninsula University of Technology, South
Africa and the University of Abertay,
Scotland.
• The study investigated the effects of head
loading and back loading on African Xhosa
females.
Head load carriage
• For a variety of reasons
(historical, economic and
practical) relatively heavy
loads are carried on the
head in much of the
developing world. In
particular, women across
Africa regularly employ
some form of head load
carriage, most often to
transport essential items
such as water and firewood.
• In Africa carrying
heavy loads are
invariably
performed by the
most vulnerable
members of society
namely women,
girls and children.
Health concerns…
• There are concerns that excessive head
loading may have negative health
implications for African females (First
International African Conference on
Gender, Transport and Development
2006).
Economic concerns
• Thus the most vulnerable people in developing
societies, namely women and girls (as head
loading is a predominant female task) are
habitually exposed to a mode of load carrying
that may have negative implications for their
health, meaning time away from work, possibly
burdening the health systems..and also
reinforcing a menial expectation of women, thus
denying them opportunities for educational and
skill development and capacitation.
“Free ride hypothesis”
• The study was initiated because of skepticism
surrounding the bold assertions made by Maloiy and
associates regarding the mechanical efficiency of
African females carrying loads on their heads. Briefly
stated, research published by *Maloiy et al in the
journal Nature (1986) contended that African females
could carry up to 20% of their body mass on their
heads without incurring any additional energy
expenditure.
• This became known as the “Free ride hypothesis”
•
*Maloiy et al (1986). Energetic costs of carrying loads: have African women discovered an
economic way? Nature, 319, 668–669..
Aligned research
• Following the profound assertions made by
Maloiy in 1986 there appears to be an absence of
research that sought to systematically test the
generalisability of the free ride hypothesis.
• Rather the subsequent literature to a large extent
tried to explain the phenomenon usually referred
to as the “Free ride hypothesis” and therefore
appears to have adopted a predominantly
inductive research approach, aimed at verifying
the claims of Maloiy et al. 1986
Contradictory findings..
• The data generated from these earlier studies is
contradictory and confounded by very small sample
sizes. On the one hand Maloiy et al (1986),
Charteris et al (1989a,b), and Nag and Sen (1978)
have all presented data, based on small samples of
4-6 participants, suggesting that head-loading is an
extremely efficient method of load carriage whilst
on the other hand Datta and Ramanathan (1971)
and Das and Saha (1966) have argued, based on
samples of 6 and 7 participants, that it is less
efficient than back-loading.
Karl Popper
• Thus, the research that was conducted following
the presumption of the “Free ride hypothesis”,
appear to have fallen victim to what Popper
referred to as the “explanatory power” of
popular theories. Popper highlights that the
customary acceptance of a theory is not unusual
for persons, particularly those prone to inductive
research paradigms, where verification of the
theory is the Objective….
•
Popper K (1963). Science: Conjectures and Refutations.
Recent research: Lloyd et al. (2010 & 2011)
• The present study was geared towards a research
design that would test a number of hypotheses
related to head and back loading with sufficiently
large group samples of participants to allow for
reasonable statistical analysis, and a more
acceptable degree of generisability to larger
populations.
• Importantly the present integrated research
project did not set out to verify the free ride
hypothesis; rather the research was aimed at
testing and possibly refuting the “Free ride
hypothesis”.
Study aim(s)
• The integrated research project
investigated whether head
loading had an effect on:
• Anthropometry, skeletal
architecture and bone density,
• Metabolic expenditure,
• Electrical activity in muscles,
• Biomechanics,
• Perceptions of effort, pain and
discomfort.
Loads
• Loads of 20%, 25%,
30%, 40%, 50%, 60%
and 70% of body
mass or until pain and
discomfort caused
cessation of the
session.
Refutation
• The research project sought to test the “Free
ride hypothesis” in African women. The mean
data presented and its attendant interpretations
provide no support for such a phenomenon,
suggesting that, on the whole, both head-loading
and back-loading are associated with a similar
increase in energy expenditure.
• It may be argued that the studies that followed
Maloiy et al 1986, were characterized by an
inductive research approach, and as a
consequence appear to have perpetuated the
‘free-ride hypothesis’.
Concluding comments..
• The presentation asserts that back-loading has
certain important advantages over head-loading.
• Most importantly it is possible to carry greater
loads on the back than on the head.
• Head-loading is characterized by significant
neck pain and long term habituation does not
seem to provide protection against this.
• It is suggested that
there is a need for
further research into
viable alternatives to
head-loading for rural
dwelling African
women, because the
present expected
method of carrying
loads is painful, limits
the total load that can
be carried, and
appears to be less
metabolically efficient
than back loading.
Conclusions
• Also, it is questionable that an inefficient
mode of transporting goods such as head
loading is beneficial to significant economic
development, and that the social and cultural
expectation that women are expected to
habitually carry out such tasks may exclude
them from education and skills programmes
that would capacitate them to make more
meaningful contributions to the economy.
Head load Articles published in 2010-11
•
•
•
•
•
•
Lloyd, R., Hind, K., Carroll, S., Truscott, J., Parr, B., Davies, S. and Cooke, C.
(2010). “A preliminary investigation of load-carrying on the head and bone
mineral density in premenopausal, black African women” Journal of Bone and
Mineral Metabolism. Vol 28 (March 2010): 185 – 190.
Lloyd, R., Hind, K., Carroll, S., Truscott, J., Parr, B., Davies, S. and Cooke, C
(2010). Subjective perceptions of load carriage on the head and back in Xhosa
women. Applied Ergonomics, 41 (2010): 522-529.
Lloyd, R., Hind, K., Carroll, S., Truscott, J., Parr, B., Davies, S. and Cooke, C
(2010). "No 'Free Ride' for African women". South African Journal of Science,
Vol 106, No (3/4): 1-5.
Lloyd, R., Hind, K., Carroll, S., Truscott, J., Parr, B., Davies, S. and Cooke, C
(2010). A comparison of the physiological consequences of head-loading and
back-loading for African and European women. European Journal of Applied
Physiology. Jul 2010. Vol. 109, Iss. 4; p. 607 – 616.
Lloyd, R., Hind, K., Parr, B., Davies, S., Cooke, C (2010). The Extra Load Index
as a method for comparing the relative economy of load carriage systems.
Ergonomics, Volume 53 Issue 12: p. 1500 – 1504.
Lloyd R, Parr B, Davies SEH, Cooke C (2011). A kinetic comparison of backloading and head-loading in Xhosa women. Ergonomics, 54(4): 380 – 391.
Contact: daviess@cput.ac.za