Research

Mixed

In chronically endurance-trained older adults, maximal oxygen uptake (VO2max) per kilogram of appendicular muscle mass is significantly reduced compared to younger counterparts, independent of age-associated changes in body composition (such as increased body fat or loss of muscle mass).

If you are an older endurance athlete, your cardiovascular system's ability to deliver oxygen to your muscles declines with age, regardless of how much you train. This is a physiological limit, not a failure of your training. Focus on maintaining your training volume and intensity to preserve muscle quality and oxidative capacity, as these adaptations are well-maintained in older subjects.

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These findings suggest that the reduced VO2 max seen in highly trained older men and women relative to their younger counterparts is due, in part, to a reduced aerobic capacity per kilogram of active muscle independent of age-associated changes in body composition, i.e., replacement of muscle tissue by fat.
David N. Proctor et al. · Journal of Applied Physiology · 1997

Why this rating

Controlled study with trained subjects, rigorous statistical adjustment (ANCOVA), and clear measurement of muscle mass via DXA.

Source

Skeletal muscle mass and the reduction ofV˙<scp>o</scp> <sub>2 max</sub> in trained older subjects

David N. Proctor et al. · Journal of Applied Physiology · 1997

DOI 10.1152/jappl.1997.82.5.1411

cross_sectional · n=32Cited 186×
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DOI resolved against Crossref · corpus check 2026-06-10

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