In pairs, note down three reasons why governments might want to measure physical activity levels in their population. Compare these with those identified by your partner and decide which reasons might be the most compelling.
Access the paper by Lee et al. (details below – you may need to create a free account to access the article). Using data presented in Table 2, make a note of the estimated population attributable fraction for each non-communicable disease and all-cause mortality associated with physical inactivity for your country. Compare the data for your country to the median value for your region and the median value worldwide. How do the estimates vary between different regions? Write a short paragraph identifying the key implications of this data for public health policy and suggest two ways the accuracy of the estimates could be improved.
Lee, I.-M., Shiroma, E.J., Lobelo, F., Puska, P., Blair, S.N. and Katzmarzyk, P.T. for the Lancet Physical Activity Series Working Group. (2012) Effect of physical inactivity on major non-communicable diseases worldwide: an analysis of burden of disease and life expectancy. Lancet 380: 219–29. https://doi.org/10.1016/S0140-6736(12)61031-9.
With a partner, come up with a clear definition of the term ‘selection bias’. The early studies by Morris et al. compared the incidence of heart attack in men who had physically active jobs (bus conductors, postmen who walked/cycled delivering mail) with the incidence in their sedentary counterparts (bus drivers, postmen sorting mail). Make short notes on how selection bias might influence the findings of such studies.
Read the paper written by Taubes (details below). Consider how relevant the issues raised in this paper are to the evidence linking physical inactivity with an increased risk for specific diseases. To what extent does epidemiological evidence develop knowledge and understanding of physical activity and health?
Taubes, G. (1995) Epidemiology faces its limits. Science 269: 164–9. https://doi.org/10.1126/science.7618077.
BASES and Human Kinetics webinar by Dr Paul Kelly: Should we reframe how we think about physical activity and sedentary behaviour measurement? (Note: you will need to create a free account).
Make a list of the strengths and limitations of the evidence linking physical inactivity, low levels of physical fitness, low levels of muscular strength and high levels of sedentary behaviour with an increased risk of all-cause mortality. Exchange your list with that of one of your classmates and discuss your answers together.
Access the latest data on the ‘Global health estimates: leading causes of death’ from the Global Health Observatory provided by the World Health Organization. Locate the latest data on the leading causes of death for your country and make a note of the top ten causes of death. Compare the data for your country to the global estimates and identify any similarities and differences. Make notes on whether the causes of death in your country have changed according to (1) time; (2) sex; and (3) age, and suggest reasons for any differences you have noticed.
With a partner, design either an observational or an intervention study that will assess the relationship between muscular strength and cardiovascular disease. You should identify the main question/s to be addressed, the study design, the type of participants you will recruit, the sample size, the outcomes you will examine, the duration of the study, the strengths and limitations of your investigation, and how your study will advance knowledge.
Access the journal article by Arem et al. (details below – you may need to create a free account to access the article). Using information presented in Table 3, construct a figure presenting the hazard ratio and 95% confidence intervals for leisure-time physical activity and cardiovascular disease mortality. Write a short paragraph summarising how these data contribute to our understanding of the level of activity that confers protection against cardiovascular disease.
Arem, H., Moore, S.C., Patel, A., Hartge, P., Berrington de Gonzalez, A., Visvanathan, K., Campbell, P.T., Freedman, M., Weiderpass, E., Adami, H.O., Linet, M.S., Lee, I.-M. and Matthews, C.E. (2015) Leisure time physical activity and mortality: a detailed pooled analysis of the dose–response relationship. Journal of the American Medical Association Internal Medicine 175: 959–67. https://doi.org/10.1001/jamainternmed.2015.0533.
Create five multiple-choice test questions relating to type 2 diabetes. Each question should include four alternative answers – one correct and three incorrect. When you have completed your questions, exchange them with those of a classmate. Now answer your classmate’s questions.
Access the ACSM position stand on ‘Exercise and type 2 diabetes’. Construct a table summarising the physical activity recommendations for individuals with type 2 diabetes using information presented in the section ‘Recommended PA participation for persons with T2DM’ (pages 2290–2292). Make a bullet point list of the potential risks and complications of exercise for those with type 2 diabetes.
Discuss with a partner the advice you would give to a 40-year-old man or woman who is obese (body mass index 31 kg m−2) but otherwise healthy and wishes to lose weight by exercising. Your advice should include information on the mode, duration, frequency and intensity of exercise, as well as tips for maintaining interest and motivation.
Access and read the editorial by Malhotra et al. (details below). Write a counter-argument to the view that ‘you cannot outrun a bad diet’. Your response should include reference to the role of physical activity in:
Malhotra, A., Noakes, T. and Phinney, S. (2015) It is time to bust the myth of physical inactivity and obesity: you cannot outrun a bad diet. British Journal of Sports Medicine 49: 967–8. http://dx.doi.org/10.1136/bjsports-2015-094911.
NCD Risk Factor Collaboration (global population-based data for body mass index)
Obesity and Energetics Offerings (weekly research and news alerts related to obesity – you can also sign up to receive the alerts in a weekly email)
In pairs, make a list of the metabolic changes that occur in response to exercise that may prevent or delay the development of type 2 diabetes. Make a distinction between changes that occur acutely in response to single exercise bouts and those that reflect adaptations to chronic exercise training.
Access the journal article by Maraki and Sidossis (details below) and read section 3 (‘Effects of a single bout of exercise on postprandial lipaemia’) and section 4 (‘Mechanisms underlying the hypotriacylglycerolaemic effect of acute exercise’). Design a study that will address a gap in our understanding of the mechanisms responsible for the postprandial TAG lowering effect of acute exercise. Provide details of the study design, participants that will be recruited, exercise protocol, outcomes that will be assessed, methods used to measure the outcomes and how the findings will advance knowledge.
Maraki, M.I. and Sidossis, L.S. (2013) The latest on the effect of prior exercise on postprandial lipaemia. Sports Medicine 43: 463–81. https://doi.org/10.1007/s40279-013-0046-9.
NCD Risk Factor Collaboration (global population-based data for cardio-metabolic risk factors)
Write down five characteristics (behavioural, dietary) that might confound studies that compare the incidence of colon cancer between groups of people who differ in their level of physical activity. Compare your list with that of a partner and discuss how, if you were planning such a study, you would address the issue of confounding.
Read the paper by Slattery and Potter (details below) and make sure that you understand and can distinguish the terms ‘confounding’ and ‘effect modification’. The researchers conclude that ‘physical activity appears to have importance beyond its independent association with colon cancer’. Make notes summarising the aspects of their findings that justify this conclusion.
Slattery, M.L. and Potter, J.D. (2002) Physical activity and colon cancer: confounding or interaction? Medicine and Science in Sports and Exercise 34: 913–9. https://doi.org/10.1097/00005768-200206000-00002.
With a partner, discuss the problems involved in cross-sectional studies that aim to compare bone mineral density in athletes and non-athletes. Write down three that you consider the most important in that they make interpretation of findings difficult.
Read the position statement of the ACSM on skeletal health (ACSM Position Stand: Physical activity and bone health). Identify and make notes on the unique contribution of animal studies to this area of research.
Select one of the anxiety disorders displayed in Table 10.2. In pairs, discuss the barriers that a patient of your chosen disorder may experience when trying to engage in physical activity and suggest how the barriers could be overcome.
Access and read the journal article by Choi et al. (details below). (1) Make notes on how Mendelian randomization allows potential causal inferences to be made from observational data. (2) Summarise the key findings supporting the authors’ conclusion that a protective relationship exists between objectively measured but not self-reported physical activity and major depressive disorder and suggest reasons for the apparent disparity in findings.
Choi, K.W., Chen, C.Y., Stein, M.B., Klimentidis, Y.C., Wang, M.J., Koenen, K.C. and Smoller, J.W.; for the Major Depressive Disorder Working Group of the Psychiatric Genomics Consortium. (2019) Assessment of bidirectional relationships between physical activity and depression among adults: a 2-sample Mendelian randomization study. Journal of the American Medical Association Psychiatry 76: 399–408. https://doi.org/10.1001/jamapsychiatry.2018.4175.
In pairs or small groups, discuss and note down the various reasons why it is harder to establish links between physical inactivity and disease in children and adolescents compared with adults. Discuss the practical difficulties you might encounter when trying to conduct research work with children and adolescents and identify ways to overcome these difficulties.
Access and read the case report by Ludwig (2012) (details below – you may need to create a free account to access the article). Write a short commentary on the potential role that physical activity could play in augmenting the physical and mental health of the patient described. Provide some recommendations on how this individual could become more active and identify the settings that could be targeted to facilitate this.
Ludwig, D.S. (2012) Weight loss strategies for adolescents. A 14-year-old struggling to lose weight. Journal of the American Medical Association 307: 498–508. https://doi.org/10.1001/jama.2011.2011.
With a partner, plot a figure showing the change in maximum oxygen uptake from age 20 to 80 years including a curve for an individual who was: (1) well trained across their life course; (2) well trained until their mid-30s; and (3) untrained across their life course. Identify the main implications of the age-related change in maximum oxygen uptake for the health and function of older adults.
Access the ACSM position stand on ‘Exercise and physical activity for older adults’. Read the section on ‘Benefits of exercise training in previously sedentary individuals’. Write a short paragraph on aerobic exercise training giving the following information:
Now do the same for resistance exercise training and balance training.
Discuss with a partner the advice you would give to a middle-aged, previously sedentary individual who wishes to improve their fitness through jogging.
Go to the ACSM’s website and locate the 2007 Position Stand on the Female Athlete Triad. Read the short section headed ‘Prevention’ and make notes on your view of the challenges involved for coaches in implementing the recommendations described.
One way for adults to fulfil current physical activity recommendations is to accumulate short bouts of activity throughout the day. With a partner, discuss the advantages and disadvantages of this approach. Write down which you consider to be the three most important in each category.
Read the paper written by Stamatakis et al. (details below). Do you think recommendations for minimising sedentary behaviour should be included in public health guidelines? What evidence is there to support your views and what gaps in knowledge remain?Stamatakis, E., Ekelund, U., Ding, D., Hamer, M., Bauman, A.E. and Lee, I.-M. (2019) Is the time right for quantitative public health guidelines on sitting? A narrative review of sedentary behaviour research paradigms and findings. British Journal of Sports Medicine 53: 377–82. https://doi.org/10.1136/bjsports-2018-099131.