The loss of strength and muscle mass that tends to occur with aging can contribute to frailty, increased falls risk, and loss of functional ability. Thus, maintaining adequate muscle strength is an important component to health and overall quality of life. A recent study in the Journals of Gerontology suggests that long-term participation in aerobic exercise may contribute more than previously thought to muscle strength.
For the study, researchers identified 74 individuals across three different age groups (20 to 29 years of age, 40 to 64, and 65 to 86), who were identified as either aerobically active (participating in four or more hours of moderate to vigorous aerobic exercise per week) or sedentary (no more than 60 minutes of physical activity per week, going back for a period of several years). These participants participated in a laboratory trial to assess their strength and fitness, including tests of grip strength, quadriceps strength, leg extension strength, and aerobic capacity.
Participants were asked to report their regular diet and give a history of their level of activity, which was used to group them by activity level and to compare dietary intake. Before completing a laboratory trial to assess their strength and fitness, participants were asked to follow a regular diet and activity plan for two days, and to abstain from taking dietary or exercise supplements (unless medically recommended) for a period of two weeks.
In contrast to previous findings on the relationship between aerobic activity and muscle strength (which has mostly been based on relatively high-performing athletes) which revealed few or no benefits of aerobic activity on muscle strength, within this study sample, aerobic activity was associated with muscle strength, even when involving seemingly unrelated physical functions. (Lower body activity was associated with hand grip strength, for example.) The aspects of strength that were significantly different between active and sedentary groups were also those that declined with age, which suggests that aerobic activity may contribute to retaining functional strength as we age.
Crane JD, MacNeil LG, and Tarnopolsky MA. Long-term aerobic exercise is associated with greater muscle strength throughout the life span. Journals of Gerontology Series A: Biological Sciences. (2013). doi: 10.1093/gerona/gls237