Exercise in Early Adulthood Improves Fitness Later

August 29, 2011 — Physical fitness in early adulthood appears to have a cumulative effect that pays off with health benefits later in life, according to new research published online August 25 in the American Journal of Preventive Medicine.

Researchers in England and Australia evaluated data on approximately 2400 men and women enrolled in the UK Medical Research Council National Survey of Health and Development who were born in March 1946 and self-reported physical activity levels prospectively at ages 36, 43, and 53 years.

The participants were assessed for grip strength, standing balance, and chair rise times by nurses at age 53 years in 1999, and again in 2010.

The results showed that participants who were more active at all 3 ages had superior performance on the chair-rise test, which is associated with lower body strength and power, in addition to cardiorespiratory fitness.

Participants who reported being more active at ages 43 and 53 years had improved performance on the standing balance test, which involves mental concentration and subtle motor control, and measures several neurophysiological sensory symptoms. Those improvements were seen even after adjusting for covariables such as height and weight, occupation, education, or health status.

Physical activity and grip strength, a measure of upper-body muscle condition, were not associated with previous activity levels in women, however. And in men, only physical activity at age 53 years was associated with improved grip strength.

The authors speculated that the chair-rising showed the greatest improvement because the types of activities the participants typically engaged in benefit lower body strength and power.

"High levels of lifetime physical activity have a positive impact on cardiorespiratory fitness, which is required to successfully complete the chair rising test," they said.

They concluded that the results were nevertheless remarkable, considering that the improvements were seen even after adjusting for various factors.

"In a nationally representative British population, evidence was found of cumulative benefits of physical activity across adulthood for physical performance in midlife," the authors wrote.

"These associations were robust to adjustment for a range of potential confounding factors."

Interestingly, only 35% of people in the study who were the most active in the group at age 53 years met the recommended level of at least 30 minutes of moderate-intensity physical activity 5 times a week, indicating that higher levels of physical activity may not even need to be achieved for there to be beneficial effects on physical performance.

The results offer important evidence that even leisure activity can provide health benefits that extend beyond the short term, said lead author Rachel Cooper, PhD, from the Medical Research Council Unit for Lifelong Health and Ageing, Division of Population Health, University College London, United Kingdom.

"Increased activity should be promoted early in adulthood to ensure the maintenance of physical performance in later life," she said in a news release. "Promotion of leisure time activity is likely to become increasingly important in younger populations as people's daily routines become more sedentary."

"When promoting physical activity, it may be necessary to encourage people to participate in specifıc types of activity in order for a benefıcial effect on upper body strength to be seen," the authors also note in the study conclusion.

Dr. Cooper and one coauthor were supported by the UK Medical Research Council, and Dr. Cooper also receives support from the HALCyon program, funded by the New Dynamics of Ageing. One coauthor received support from the Australian National Health and Medical Research Council. The other authors have disclosed no relevant financial relationships.

Am J Prev Med. Published online August 25, 2011. Full text