Exercise in old age

• there is evidence from high quality studies to strongly support the positive association between increased levels of physical activity, exercise participation and improved health in older adults (1,2,3)
  • worldwide, around 3.2 million deaths per year are being attributed to inactivity(1)
    
    
• key factors in improving health are exercising at a moderate-to-vigorous level for at least 5 days per week and including both aerobic and strengthening exercises (1,4)
  
  
• five leading risk factors for death are high blood pressure, smoking, high blood glucose, physical inactivity and obesity (1)
  • high blood pressure and glucose levels as well as obesity are connected with physical inactivity
    • as well as the increasing incidence of these risk factors with ageing, there is a decline in many physiological systems; a loss of muscle mass, a decline in balance ability, a reduction in muscle strength and endurance and a decline in cognitive performance, all of which impact on functional independence
  • increasing physical activity levels is the most important intervention to improve health in populations (3)
    
    
• in a study examining the effects of physical activity on healthy aging - defined as those participants who survived without developing major chronic disease, depressive symptoms, physical or cognitive impairment (2)
  • examined the association between physical activity and healthy ageing over 8 years of follow-up
    • participants were 3454 initially disease-free men and women (aged 63.7+/-8.9 years at baseline) from the English Longitudinal Study of Ageing - a prospective study of community dwelling older adults
      • in comparison with inactive participants, moderate (OR, 2.67, 95% CI 1.95 to 3.64), or vigorous activity (3.53, 2.54 to 4.89) at least once a week was associated with healthy ageing, after adjustment for age, sex, smoking, alcohol, marital status and wealth
      • becoming active (multivariate adjusted, 3.37, 1.67 to 6.78) or remaining active (7.68, 4.18 to 14.09) was associated with healthy ageing in comparison with remaining inactive over follow-up
        • i.e. remaining active over the eight year period of the study conferred a seven times increased chance of an individual being healthy in old age compared to his/her inactive peers
    • sustained physical activity in older age is associated with improved overall health
      • this study revealed significant health benefits were even seen among participants who became physically active relatively late in life
        
• in a cohort study among 45 176 female participants in the Nurses’ Health Study, sedentary behavior was associated with reduced odds of healthy aging, while light physical activity was associated with increased odds of healthy aging (5)
  • replacing television time with light physical activity, moderate to vigorous physical activity, or sleep (in participants with inadequate sleep) were associated with better odds of healthy aging
    
    
• a summary of the WHO recommendations for exercise for people aged 65 years and older
  
  
  • at least 150 min of moderate-intensity aerobic activity, or at least 75 min of vigorous-intensity aerobic activity, or an equivalent combination
    
    
  • aerobic activity should be performed in bouts of at least 10 min duration
    
    
  • for additional health benefits, undertake up to 300 min of moderate-intensity or 150 min of vigorous-intensity aerobic activity, or an equivalent combination
    
    
  • people with poor mobility should do balance exercise to prevent falls on 3 or more days
    
    
  • muscle-strengthening activities should be done on two or more days
    
    
  • if older adults are unable to do the recommended amounts of physical activity due to health conditions, they should be as physically active as they are able.

Measurement of Physical Activity

• perceived rate of exertion
  • in guidelines such as those published by the American College of Sports Medicine (ACSM), a simple scale of intensity based on a self-perceived rate of exertion is used
    • scaled from 0-10
      • with 5-6 being moderate-intensity exercise
      • and 7-8 being vigorous-intensity exercise
      • ACSM guidelines clarify physical activity intensity by describing sitting as 0 and the greatest effort possible is 10, with moderate-intensity activity being 5 or 6 and producing noticeable increases in breathing and heart rates, and vigorous-intensity activity (7-8) producing large changes in breathing and heart rates
        
        
• metabolic equivalent
  • method of calculating intensity of physical activity or exercise is the metabolic equivalent (MET) value, which is an indicator of energy expenditure
    • one MET is roughly equivalent to the energy expended during quiet sitting
      • physical activities have been categorised to produce a compendium of MET values, for example, bicycling at a leisurely pace of 5.5 mph has a MET value of 3.5 and washing dishes has a MET value of 1.8
        • the contents of the compendium can be accessed freely at https://sites.google.com/site/compendiumofphysicalactivities/
    • physical activity that is below 3.5 METS (light activities) or a total amount of activity that is below around 4200 kJ/week (equivalent to more than 3 h of brisk walking per week) is unlikely to produce health-related changes in adults (1)

Different types of physical activity and exercise

• strength and aerobic fitness (1)
  • strong evidence for the effectiveness of aerobic exercises and muscle-strengthening exercises
    • aerobic exercise - defined as any type of activity that uses large muscle groups and can be maintained over a period of time including activities such as brisk walking, swimming or dancing
      • aerobic exercise should be at a moderate level, in which the individual notices increases in heart rate and breathing rate
    • resistance-based strengthening requires muscles to work against a load, which may be an external load or bodyweight that is progressively increased over the time of the programme
      • most of the trials of progressive resisted strength training in older adults have high-intensity strength training protocols, most frequently involving 8-12 repetitions of the exercise to the point of muscle fatigue
        • programmes usually involve the support of exercise professionals and are usually based in gymnasiums, as specialist equipment is often used
  • strength training exercise is recommended for improving physical function in older adults (6)
    • a systematic review and meta-analysis was undertaken to investigate whether strength training (lifting and lowering weights under control) versus power training (PT) (lifting weights fast and lowering under control) associated with better improved physical function in older adults
    • concluded that:
      • PT was associated with a modest improvement in physical function compared with traditional strength training in healthy, community-living older adults

Reference:

• Taylor D.Physical activity is medicine for older adults.Postgrad Med J. 2013 Nov 19. doi: 10.1136/postgradmedj-2012-131366
• Hamer M et al. Taking up physical activity in later life and healthy ageing: the English longitudinal study of ageing. Br J Sports Med doi:10.1136/bjsports-2013-092993
• Paterson D, Jones G, Rice C . Ageing and physical activity: evidence to develop exercise recommendations for older adults. Appl Physiol Nutr Metab 2007;32(Suppl 2E):S69-108
• World Health Organization. Global recommendations on physical activity for health. Geneva: World Health Organisation, 2010.
• Shi H, Hu FB, Huang T, et al. Sedentary Behaviors, Light-Intensity Physical Activity, and Healthy Aging. JAMA Netw Open. 2024;7(6):e2416300. doi:10.1001/jamanetworkopen.2024.16300
• Balachandran AT, Steele J, Angielczyk D, et al. Comparison of Power Training vs Traditional Strength Training on Physical Function in Older Adults: A Systematic Review and Meta-analysis. JAMA Netw Open. 2022;5(5):e2211623. doi:10.1001/jamanetworkopen.2022.11623