Midlife Cardiorespiratory Fitness Predicts How Well We Age

Kenneth H. Cooper Institute at TTUHSC Releases 30-Year Study’s Findings

• By Kay Williams
• April 23, 2026
• Health

Being fit in midlife helps people live longer and healthier, according to new research findings from the Kenneth H. Cooper Institute at Texas Tech University Health Sciences Center.

The observational cohort study, which followed nearly 25,000 adults for an average of  30 years after a preventive medicine examination, found that higher levels of cardiorespiratory fitness in middle age were linked to longer life, fewer chronic diseases and more years lived in good health after age 65. The findings were published today (April 22) in the Journal of the American College of Cardiology.

“The study shows that cardiorespiratory fitness in midlife is a powerful predictor of how well we age,” Clare Meernik, Ph.D., lead author, epidemiologist at the Cooper Institute and research assistant professor in the TTUHSC Julia Jones Matthews School of Population and Public Health, said. “If you are fitter in midlife, you don’t just live longer. You are more likely to stay healthier longer and develop fewer diseases as you age.”

Meernik and her team analyzed data from the Cooper Center Longitudinal Study, which included generally healthy men and women in their mid-40s, on average, who underwent a medical examination with fitness testing at the Cooper Clinic in Dallas from 1971 to 2017. 

Participants’ clinic data were then linked to later life Medicare claims to track the onset of 11 major chronic diseases, such as cancer, heart disease and dementia. On average, participants entered Medicare 19 years after their clinic exam and were followed for another 10 years after age 65. This prolonged interval allowed evaluation of how well the study participants aged.

Compared with low-fit men and women, those in the high-fit category lived 2 to 3% longer, or 1.4 to 2.3 additional years and had a 2% longer healthspan, or 1.3 extra years lived in good health before the onset of major chronic disease. High-fit study participants also developed 9 to 12% fewer chronic diseases as they aged than low-fit study participants. 

“Results were consistent across sexes, showing that fitness is a powerful predictor of aging in both men and women,” Meernik said. 

Senior author Laura DeFina, M.D., executive director of the Cooper Institute and research professor in the Julia Jones Matthews School of Population and Public Health, noted, “This study moves beyond previously established associations between cardiorespiratory fitness, single disease outcomes and mortality and highlights the prognostic importance of fitness in relation to disease-free longevity.” 

Meernik added that results support long-held health advice to exercise to be fit.

Originally a non-profit founded by Kenneth H. Cooper, M.D., MPH, in 1970, the Cooper Institute is dedicated to promoting lifelong health and wellness through research and education.