You’re Never Too Old to Start Exercising

Canadians from the ages of 18 to 64 are urged to participate in at least 150 minutes of moderate- to vigorous-intensity aerobic physical activity per week along with muscle and bone-strengthening activities at least twice a week (1). This amount of exercise can bestow substantial health benefits such as reduction in the risk of premature death, heart disease, stroke, high blood pressure, certain types of cancer, type-2 diabetes, osteoporosis, overweight and obesity in addition to increased fitness, strength and mental health (2,3,4,5,6).

Most people are quite aware of these benefits. However, life is not as uncomplicated as simply planning to exercise regularly and seeing it through. Daily realities and responsibilities can become significant hurdles to fulfilling this goal. With work commitments and child rearing, it is often not until the end of the day when leisure activities can finally be contemplated. By then though, energy levels are often low and weariness can sabotage all good intentions. So it is exciting and inspiring to read the results of a new study that was recently published (March, 2019) in JAMA, the Journal of the American Medical Association. This research brings us the good news that it is never too late to gain the health advantages that come from incorporating more physical activity into your life.

In this prospective cohort study researchers looked at physical activity throughout life. Over 315,000 participants in the National Institutes of Health-AARP Diet and Health Study were sorted into one of four life stages; adolescence (15 to 18 years of age); early adulthood (19 to 29 years of age); middle adulthood (35 to 39 years of age); and late adulthood (40 to 61 years of age). With the help of the US National Death Index mortality records, the relationship between exercise and mortality from all-causes, cardiovascular disease and cancer were determined and analyzed (7).

Researchers identified ten trajectories of leisure time physical activity based on exercise in late adulthood relative to that of adolescence. These trajectories were then classified into three categories;
“Maintainers” – Participants with consistently high or stable physical activity over time
“Increasers” – Participants who increased physical activity starting from adolescence or not until late adulthood
“Decreasers” – Participants who were active in early adulthood but reduced their activity level at later stages

Here are the results:
In “Maintainers”, expected health benefits were seen;
Compared to those who were consistently inactive throughout adulthood;

• Those who maintained moderate to high amounts of physical activity (2 to 8 hours per week)
  had a 29% to 36% lower risk in all-cause mortality, a 34% to 42% lower risk for CVD-related
  mortality and a 14% lower risk of cancer-related death.
• Those who maintained low levels of physical activity (about 1 hour a week) showed a 16% lower
  risk in all-cause mortality, an 18% lower risk in CVD-related mortality and a similar risk of
  cancer-related death.

 

The results for “Increasers” were surprising;
Compared to those who were consistently inactive throughout adulthood;

• Increasing physical activity in early adulthood had a 32% lower risk of all-cause mortality.
• Increasing physical activity in late adulthood had a 35% lower risk of all-cause mortality.
• Increasing physical activity in late adulthood had a 43% lower risk of CVD-related mortality.
• Increasing physical activity either early or late in adulthood had a 16% lower risk of cancer-related death.

 

“Decreasers”, on the other hand, with high physical activity in early adulthood but low physical activity during subsequent life stages, had little protection from early death due to all-causes, CVD-related mortality or cancer-related mortality.

 

Bottom line:

Adults who become physically active later in life can gain lowered mortality rates similar to those of lifelong exercisers.
On the other hand, most of the benefits of physical activity early in life are lost if the activity is not maintained or restarted.
Benefits were similar in both men and women and were independent of changes in BMI (Body Mass Index) over time.
Previous studies have shown lower risk of all-cause mortality with increasing physical activity (8) but this is the first research assessing participation in physical activity over many decades and the implications of changes in exercise at different life stages. It is also the first study to separate out the effects of exercise on two specific causes of death, cardiovascular disease and cancer.

This is excellent news for older people. It tells us that there is no need to feel like the opportunity to regain a good level of fitness has slipped through your fingers. You will be amply rewarded by ramping up your physical exercise at any stage of life. Pick your activity, start slowly, gradually increase your exercise intensity and soon you will reap the many healthful benefits of physical fitness.

 

SOURCES:

1 https://csepguidelines.ca/adults-18-64/

2 Arem, H., Moore, S.C., Patel, A., et al. Leisure time physical activity and mortality: a detailed pooled analysis of the dose-response relationship. JAMA Intern Med. 2015;175(6):959-967.

3 Nocon, M., Hiemann, T., Müller-Riemenschneider, F., Thalau, F., Roll, S., Willich, S.N. Association of physical activity with all-cause and cardiovascular mortality: a systematic review and meta-analysis. Eur J Cardiovasc Prev Rehabil. 2008;15(3):239-246.

4 Wahid, A., Manek, N., Nichols, M., et al. Quantifying the association between physical activity and cardiovascular disease and diabetes: a systematic review and meta-analysis. J Am Heart Assoc. 2016;5(9):e002495.

5 Li, T., Wei, S., Shi, Y., et al. The dose-response effect of physical activity on cancer mortality: findings from 71 prospective cohort studies. Br J Sports Med. 2016;50(6):339-345.

6 Li, Y., Gu, M., Jing, F., et al. Association between physical activity and all cancer mortality: dose-response meta-analysis of cohort studies. Int J Cancer. 2016;138(4):818-832.

7 Saint-Maurice, P.F., Coughlan, D., Kelly, S.P., Keadle, S.K., Cook, M.B., Carlson, S.A., Fulton, J.E., Matthews, C.E. Association of Leisure-Time Physical Activity Across the Adult Life Course With All-Cause and Cause-Specific Mortality. JAMA Netw Open. March 8, 2019;2(3):e190355.

8 Byberg, L., Melhus, H., Gedeborg, R., et al. Total mortality after changes in leisure time physical activity in 50 year old men: 35 year follow-up of population based cohort. Br J Sports Med. 2009;43(7):482.