CHAPTER 2: The quality of science underpinning
sport and exercise science and medicine
Sport and exercise science and
medicine
11. Sport and exercise science (SES) is the application
of fundamental and applied sciences to the sport and exercise
environment;[16] and
findings from a variety of different areas of science, including
physiology, biomechanics, nutrition, genetics and psychology,
are applied to the study of sport and exercise.[17]
In 2001-07, research income for "sports-related studies"
was £31.2 million.[18]
12. Sport and exercise medicine (SEM) has been
recognised recently as a specialty by the National Health Service
(NHS).[19] It is concerned
with "all aspects of health and illness that may prevent
a person from engaging in, or returning to, sporting or physical
activity".[20] The
NHS define SEM as "the management of medical conditions and
injury in those who participate in physical activity".[21]
The specialty also includes expertise in exercise advice, prescription
and promotion for general health, and for those with chronic medical
problems.[22] The research
subjects of both SES and SEM include elite athletes, non-elite
athletes and the wider public. There is some overlap between the
two fields.
13. In this chapter, we consider the use of science
to improve the performance of elite and non-elite athletes, and
the scientific study of physical activity in the wider population.
We also explore the relevance of findings from research in SES
and SEM to the wider public.
Quality of SES and SEM research
14. Before considering whether SES and SEM research
can be translated into public health benefits, it is necessary
to consider whether the research is sufficiently robust—in
the sense that it is based on accepted scientific methodology—to
justify translation. The scientific method involves systematic
observation, measurement, and experiment, and the formulation,
testing, and modification of hypotheses.[23]
Replication of research results and appropriate statistical analysis
are necessary before a result is widely accepted.
15. Several witnesses referred to the difficulties
of conducting good quality research with elite athletes. A principal
difficulty was the limited number of elite athletes to test and,
therefore, small sample sizes.[24]
Furthermore, many elite athletes are reluctant to allow invasive
procedures, such as blood sampling and tissue biopsies, for fear
they would interfere with performance.[25]
We were told that another common difficulty was creating control
groups, because athletes, and their support staff (such as coaches),
were seeking a "competitive edge" and so would not consent
to such arrangements.[26]
As a consequence, research on elite athletes tends to be descriptive
or anecdotal rather than systematic. Given that some of these
difficulties are intractable because of the very nature of elite
performance, using non-elite athletes offers a more effective
alternative subject for research in these fields.
16. A number of witnesses were positive about
the quality of research. For example, Professor Myra Nimmo,
Head of School of Sport, Exercise and Health Sciences and Professor of
Exercise Physiology of Sport, Loughborough University, argued
that the quality of SES research, on the whole, was excellent.[27]
Colonel John Etherington, Vice-President, Faculty of Sport and
Exercise Medicine (UK), and Director, Defence of Rehabilitation
and Consultant in Rheumatology and Rehabilitation at the Defence
Medical Rehabilitation Centre, Headley Court, said that "the
model of the science is very good" in SES.[28]
Professor Tim Cable, Director of the School of Sport and
Exercise Sciences and Professor of Exercise Physiology, Liverpool
John Moores University, was confident of the rigour of science
in SES, and gave the examples of the physiological adaptations
that can be provoked by certain training regimens, brain behaviour
adaptations seen in learning skills, and biomechanical adaptations.
He argued these were are all based on sound scientific evidence.[29]
17. Other witnesses, however, suggested that
the quality of sport science research was generally weak. The
Physiological Society said that an "increased amount of robust
research" was being undertaken, but were critical of the
quality of research both in SES and SEM.[30]
Much of the research presented in our sport science seminar was
observational and anecdotal, so the results of such research must
be viewed as no more than provisional.[31]
Observational research needs to be followed up with rigorous testing
of hypotheses in controlled experiments with sufficient sample
sizes for statistical analysis. There are voluntary guidelines
promoting good quality SES research but it is not clear how widely
they are followed.[32]
The RCP and Ministry of Defence (MOD) were critical of weak methodologies
employed in SEM, and suggested that there was a "focus on
more esoteric areas".[33]
They pointed to a lack of good quality, large-scale trials, with
appropriate outcome measures,[34]
which Colonel Etherington summarised as a lack of "rigour
in approach to clinical trials in sport and exercise medicine".[35]
18. UK Sport argued that measuring quality of
research by its methodology risked ignoring the "end user".
UK Sport suggested that other factors had to be considered such
as performance impact, adoption of findings, and behaviour change.[36]
Professor Greg Atkinson, Professor in Exercise
and Human Health Research, Teesside University, and Professor David
Patterson, Chair, Institute of Sport and Exercise Medicine and
Professor of Cardiovascular Medicine, Centre for Health Informatics
and Multiprofessional Education, University College London (UCL),
made the case for the value of observational studies.[37]
19. We accept the importance of outcomes, and
the merits of observational research as the first step to full
scientific investigation. However, if the research in this field
is to be of value, it must be rigorous. For example, it should
be able to stand-up to the widely used test of peer-review and
be of comparable quality to research in fundamental disciplines
such as physiology.
20. During the course of this short inquiry
we were presented with little evidence to suggest that the enhancement
of the performance of elite athletes is generally based on strong
biomedical science. Given the difficulties associated with conducting
research with elite athletes, it is important to develop a two-way
flow between, on the one hand, observations on elite athletes
and, on the other hand, rigorous research on non-elite athletes
and the wider public.
Improving the performance of elite
athletes
21. The examples in Box 1 illustrate the quality
of science underpinning attempts to improve elite performance.
BOX 1
Examples of use of science to improve
elite sporting performance
- Training at altitude has become
increasingly popular amongst elite athletes. Exercising at altitude
leads to increased ventilation, increased heart rate, decreased
stroke volume, reduced plasma volume, and lower maximal aerobic
power. This enables athletes to push their limits in training.
It is also claimed that the technique, known as hypoxic training,
increases the level of haemoglobin and thus the oxygen carrying
capacity of the blood. This will help to reverse the effect of
altitude to reduce exercise performance. When athletes then return
from altitude, they experience performance benefits at sea level.[38]
Professor Hugh Montgomery of University College London, who
has pioneered much of this work, explained that whilst "we
know that it does work", what is less clear are "the
reasons why and how to manipulate it".[39]
- Ice baths are increasingly used by elite athletes
to accelerate recovery from training. There is limited scientific
evidence to support this technique, with no evidence from controlled
trials that post-exercise cooling with an ice bath enhances recovery
and improves subsequent performance.[40]
- The increase in metabolism during high intensity
exercise can generate free radicals which can damage mitochondria
and other organelles inside muscle cells. In an attempt to counteract
this potential free-radical damage there is substantial consumption
of antioxidants by athletes. However, evidence from Professor Jose Viña
shows clearly that antioxidant supplementation does not have such
protective effects and may, in fact, prevent the benefits normally
seen with exercise training.[41]
- One aspect of nutritional manipulation which
has been shown to be beneficial in terms of performance during
prolonged endurance exercise (such as marathon running) is carbohydrate
loading. This technique was originally developed in experimental
studies in non-elite athletes, and showed that continuing training
while on a low carbohydrate diet would deplete the muscle carbohydrate
(glycogen) stores, but when followed immediately by 2-3 days of
a high carbohydrate diet this would lead to an overshoot of recovery
of glycogen (supercompensation) which led to enhanced muscle glycogen
levels at the start of an endurance event. This, in turn, ensured
a sustained supply of carbohydrate fuel for the muscles and better
endurance performance and was subsequently adopted by elite athletes.
The specific detail of this regime has been modified over the
years with subsequent research on non-elite athletes then applied
to the elite, in order to ensure sustained improvement in performance
with less extreme dietary manipulations.[42]
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USE OF THE LATEST DEVELOPMENTS IN SCIENCE TO IMPROVE
ELITE PERFORMANCE
22. The UK has internationally recognised expertise
in many fields relevant to SES and SEM. For example, Professor Jose Viña,
Department of Physiology, University of Valencia, referred to
the UK's leading research in fields relating to the improvement
of performance, such as metabolic research applied to the physiology
of muscle.[43] In this
context, we considered whether SES and SEM for elite athletes
were being informed by the latest developments in, for example,
physiology, biomechanics, genetics and nutrition. Professor Gerta Vrbova,
Emeritus Professor of Developmental Neuroscience, UCL, suggested
not. She told us that SEM departments are "often poorly equipped"
to apply advances in science to problems in their field.[44]
The Physiological Society said that although there was significant
potential for fundamental scientific research to "feed into"
performance enhancement of elite (and non-elite) athletes, that
potential was often not fulfilled.[45]
The evidence we received has led us to the view that the latest
advances in relevant areas of biomedical research are not being
consistently applied to improving the performance of elite athletes.
Robust methodologies must be applied to SEM and SES for them to
have maximum effect, and to enable a two-way flow of research
between the fundamental and applied disciplines.
USE OF SCIENCE BY UK SPORT
23. UK Sport is a DCMS arm's length body. They
have a research and innovation budget of £7.5 million (for
the period 2009-13) from a combination of Government and National
Lottery funding,[46]
and attract over £12 million in "external funding".[47]
We asked Liz Nicholl, Chief Executive of UK Sport, about their
approach to science relevant to their remit. She told us that
the agency's primary objective was to win more medals in competitions.
As a result, their focus was on outcomes stemming from the application
of science rather than scientific methodologies used.[48]
UK Sport said they relied on the providers of science to do the
quality assurance.[49]
We were surprised by this since ensuring that robust science is
used would increase the likelihood that interventions to improve
competitive performance are effective. We note that UK Sport has
a science research advisory group to provide "advice on research
and development projects" and to evaluate "the effectiveness
of projects annually",[50]
but, if the science used by UK Sport is to be as effective as
possible in improving performance, it must be consistently robust
and verified as such. A review in 2005 by the Office of Science
and Technology concluded that DCMS needed to satisfy itself of
the quality assurance of science by its arm's length bodies, such
as UK Sport.[51] Neither
DCMS officials nor Hugh Robertson MP, Minister for Sport
and the Olympics at DCMS, convinced us that the department has
the capacity to undertake this task.[52]
We recommend that DCMS and UK Sport take steps to ensure that
the biomedical science UK Sport applies to improving the performance
of elite athletes is of the highest quality and meets international
peer-review standards that would be applicable in other areas
of science.
24. We were also disappointed by the approach
of UK Sport to sharing the findings of research. Little of the
agency's work is published in peer-reviewed journals, and many
of its results are not publicised in order to protect a competitive
edge.[53] We heard one
good example of findings being shared: the publication of the
findings of a UK Sport workshop on early treatment of muscle strains.[54]
But we did not receive evidence to suggest that this type of work
is undertaken often. We recommend that UK Sport should, as
a matter of principle, undertake to share its research findings
more widely, especially where the research is publicly funded.
HEALTH BENEFITS OF PHYSICAL ACTIVITY
25. There is a significant body of evidence regarding
the health benefits of physical activity and the use of exercise
to manage chronic disease. For example, DH referred to research
demonstrating that physical activity can be effective in the prevention
and management of over 20 chronic conditions, including coronary
heart disease, stroke, type two diabetes, cancer, obesity, mental
health problems and musculoskeletal conditions.[55]
They argued that the research on disease management is robust
because it is supported by randomised controlled trials.[56]
Professor David Jones, Emeritus Professor of Muscle
Physiology, Manchester Metropolitan University, told us about
research into the role exercise can play in preventing the development
of obesity, diabetes and cardiovascular disease.[57]
26. The Chief Medical Officers' Physical Activity
Guidelines are based on a literature review of the latest research
into physical activity. Most involves population-level studies
that show correlations between physical activity and health outcomes.[58]
What is less well understood are the underpinning mechanisms which
would explain these effects.[59]
Research into increasing our understanding of these underpinning
mechanisms could unlock benefits for athletic performance and
for public health, in relation to managing illness and disease
prevention. For instance, understanding the cellular or molecular
processes that underpin changes in muscle mass have applications
for both. There seems to be sufficient evidence to demonstrate
a causal link between physical activity and health benefits for
a very wide range of diseases. However, the reasons for this link
are not well understood. Research to understand these underpinning
mechanisms could be of benefit to elite athletes, non-elite athletes
and the wider public.
Relevance of findings from the
study of elite and non-elite athletes to the wider public
27. Where there is good quality evidence from
the study of elite and non-elite athletes, we considered whether
findings from such research in SES and SEM were relevant to the
wider public. Some witnesses challenged the relevance of studies
of elite athletes to the general population. Professor Sir Steve
Bloom, Head of Division for Diabetes, Endocrinology and Metabolism,
and Chair of the Academic Section of Investigative Medicine, Imperial
College London and Chief of Service for Pathology at Imperial
College Healthcare NHS Trust, said: "I cannot see any area
of research that has come out of competitive training that is
actually helpful to the general population",[60]
and Dame Sally Davies, Chief Medical Officer (England) and
Chief Scientific Adviser, DH, was "not convinced there is
vast transferability".[61]
These views were, however, the exception.
28. Colonel Etherington argued that the principles
of exercise to produce a physiological adaptation were applicable
to the wider public:
"whereas the minutiae of the physiological enhancement
to get that last 2% to win a gold medal may not be so relevant
to the elderly patient with osteoarthritis of the knee, the principles
of strength training and general conditioning are".[62]
The RCP provided two examples of research "pulled-through"
to benefits for the general population: they suggested that the
management of the diabetes of elite sportsmen has begun to inform
the principles of diabetic care in the exercising population;
and that work with athletes had informed the use of exercise and
muscle conditioning to improve back and knee pain in osteoarthritis.
They concluded that, whilst there was potential for lessons learnt
from the study of athletes to be applied to general population,
this was not always happening.[63]
29. Professor Alison McConnell, Professor of
Applied Physiology at Brunel University, argued that:
"by understanding the limits of human performance
(for example, cardiac output, muscle blood flow) and by gaining
an understanding of how to optimise interventions to achieve specific
goals, exercise science can contribute to the development of exercise-related
interventions for patients".[64]
The Physiological Society made a similar argument:
"understanding of elite performance physiology,
being located on one extreme of a continuum of human states (from
elite, through the normal range to various disease states), can
provide unique insight into physiological mechanisms of relevance
to heart disease, respiratory disease, ageing, muscle wasting,
obesity, diabetes". [65]
Professor David Mullineaux, Professor in
Sports Science, School of Sport, Coaching and Exercise Science,
Faculty of Health and Life Sciences, University of Lincoln, suggested
that, although there was great potential to transfer understanding
of elite athletes to improve the health of the wider public, this
avenue of research was underexplored.[66]
30. Where there is a good scientific basis,
lessons could be learnt from the study of elite and non-elite
athletes that have relevance to the wider public. This "trickle
down" of research from athletes to public health benefits
will be even more valuable where underpinning mechanisms are better
understood.
31. This is a potentially valuable area of research
which could have a variety of applications: preventative measures
and treatments for members of the public who exercise infrequently
(for example, weekly rather than daily); providing underpinning
knowledge for more detailed exercise guidance; and developing
new interventions based on knowledge of physiological responses.
We would hope that research and innovation to support Paralympians
also filters through to benefit the wider public. In the next
chapter, we consider the barriers to translation and how they
can be reduced so as to enable greater "trickle-down"
of research to benefits for the wider population.
16 Based on the definition by the British Association
of Sport and Exercise Sciences (BASES) at http://www.bases.org.uk/About. Back
17
Ibid. Back
18
RAE 2008: Subject Overview Report: Unit of Assessment 46 Sport-Related
Studies, January 2009. Back
19
DH. Back
20
http://www.medicalcareers.nhs.uk/specialty_pages/medicine/sport_and_exercise_medicine.aspx.
Back
21
Ibid. Back
22
Ibid. Back
23
Oxford University Press: Oxford English Dictionary, 2010. Back
24
Q 90. Back
25
Q 11, RCP. Back
26
Professor Atkinson, Professor Mullineaux, The Physiological Society. Back
27
See Appendix 5. Back
28
Q 7. Back
29
Q 4. Back
30
The Physiological Society. Back
31
See Appendix 5. Back
32
Professor Atkinson, BASES. Back
33
RCP, MOD. Back
34
Ibid. Back
35
Q 8. Back
36
UK Sport. Back
37
Professor Atkinson, Q 90. Back
38
See Appendix 5, RL Wilber: 'Application of altitude/hypoxic training
by elite athletes', Medicine and Science in Sports and Exercise,
2007, M Vogt and H Hoppeler: 'Is hypoxia training good for muscles
and exercise performance?', Progress in Cardiovascular Disease,
2010. Back
39
Q 11. Back
40
KL Sellwood, P Brukner, D Williams, A Nicol and R Hinman: 'Ice-water
immersion and delayed-onset muscle soreness: a randomised controlled
trial', British Journal of Sports Medicine, 2007, M Yamane,
H Teruya, M Nakano, R Ogai, N Ohnish and M Kosaka M: 'Post-exercise
leg and forearm flexor muscle cooling in humans attenuates endurance
and resistance training effects on muscle performance and on circulatory
adaptation', European Journal of Applied Physiology, 2006,
Appendix 4. Back
41
MC Gomez-Cabrera, E Domenech, M Romagnoli, A Arduini, C Borras,
FV Pallardo, J Sastre and J Viña: 'Oral administration
of vitamin C decreases muscle mitochondrial biogenesis and hampers
training-induced adaptations in endurance performance', American
Journal of Clinical Nutrition, 2008, MC Gomez-Cabrera, M Ristow
and J Viña: 'Antioxidant supplements in exercise: worse
than useless?', American Journal of Physiology, 2010. Back
42
E Hultman, and J Bergström: 'Muscle glycogen synthesis in
relation to diet studied in normal subjects', Acta Medica Scandinavica,
1967, LM Burke: Sports nutrition in JW Erdman, IA
Macdonald, SH Zeisel (eds): Present Knowledge in Nutrition,
10th Edition, 2012. Back
43
Professor Viña. Back
44
Professor Vrbova. Back
45
The Physiological Society. Back
46
Supplementary evidence from UK Sport. Back
47
http://www.uksport.gov.uk/pages/research-innovation/. Back
48
Q 89. Back
49
Q 70. Back
50
UK Sport. Back
51
Office of Science and Technology: Science review of DCMS,
2005. Back
52
QQ 41-42, QQ 135-136. Back
53
Q 134. Back
54
http://www.uksport.gov.uk/news/muscle_strain_think_tank/. Back
55
DH. Back
56
Op. cit. Sport and Exercise Medicine: A Fresh Approach. Back
57
Professor Jones. Back
58
DH, see Appendix 5. Back
59
See Appendix 5. Back
60
Q 14. Back
61
Q 44. Back
62
Q 7. Back
63
RCP. Back
64
Professor McConnell. Back
65
The Physiological Society. Back
66
Professor Mullineaux. Back
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