Physical activity is necessary at all stages of adult life

A recent study published in JAMA Network Open found that meeting physical activity (PA) guidelines has a stronger effect on reducing mortality risk with age, while the effects of other health factors such as weight, smoking, and blood pressure decline over time.

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Key findings

1. Physical activity and mortality risk reduction

   • Regular physical activity is associated with a significant reduction in mortality risk across all age groups, particularly in older adults.
   • Participants meeting recommended levels of PA (150–300 minutes of moderate or 75–150 minutes of vigorous activity per week) reduced their risk of mortality by 14%.
   • Physical activity levels 4–5 times higher than recommended (22.5–30 MET hours per week) provided the greatest risk reduction of 26%.

2. Influence of age

   • The effectiveness of PA in reducing mortality risk increased with age, while the influence of other health factors (non-smoking, normal weight, absence of diabetes and hypertension) weakened.
   • In older people, physical activity was found to be a more significant factor in preventing mortality than, for example, the absence of hypertension or maintaining a normal weight.

3. Positive effect even from minimal levels of PA

   • Even achieving half the recommended level of physical activity (3.75 MET-hours per week) resulted in an 8% reduction in mortality risk.

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Context and methodology

• Background
  Research has already shown a link between physical activity and reduced mortality, but its dependence on age is not well understood. With age, the level of physical activity decreases, and the risk of mortality increases. In addition, the causes of death change with age: in young people, infections and injuries predominate, while in older people, non-communicable diseases such as cardiovascular diseases and cancer predominate.

• Study design

  • The study included data from 2,011,186 participants from four large international cohort studies (USA, UK, China, Taiwan).
  • The average age of the participants was 49.1 years, 55% of whom were women.
  • Physical activity levels were measured in metabolic equivalents (METs).
  • Participants were followed for 11.5 years, with mortality data recorded.

• Analysis methods
  The researchers used regression models and sensitivity analyses to assess the associations between PA, other modifiable health factors, and mortality.

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Limitations of the study

• Self-reported data on physical activity and health factors may be subject to error.
• PA was assessed at only one point in time, which precludes the possibility of analyzing changes in activity over time.
• Not all types of physical activity (e.g. work) were taken into account.

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Conclusion

1. Physical activity is a key factor in health

   • The results highlight the importance of regular physical activity throughout life, especially for older adults.
   • Unlike other health factors such as weight or smoking, the effect of PA remains significant with age.

2. The need for individualized recommendations

   • The study highlights the importance of developing age-specific physical activity guidelines to help maximise the benefits.

3. Call for the popularization of FA

   • Promoting regular physical activity should be a priority for health systems to improve longevity and overall health outcomes across age groups.