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Nine Year Study Tracks Aging In Lifelong Cyclists Over 64

Even dedicated exercisers lose real fitness and muscle with age, but the study suggests staying active keeps you far ahead of sedentary peers.

By Dr. Axe Editorial Team · September 30, 2026 · 1 source · Watch

Photo: Pexels

A nine-year follow-up of older competitive cyclists published in GeroScience found peak oxygen consumption, a measure of cardiorespiratory fitness, dropped 19.7% even in adults who kept exercising into their 70s and 80s.

9-yearfollow-up

82older cyclists

Researchers retested 82 of 125 competitive older cyclists first assessed in 2012-2013, now 64 to 86 years old, nine years later. Peak oxygen consumption, the primary measure of cardiorespiratory fitness, fell 19.7%, from 44.1 to 35.4 ml per kg of body weight per minute. Body weight held steady, but lean tissue mass dropped 8.1% and body fat percentage climbed from 23.8% to 29.2%. Lung function declined; blood pressure and metabolic markers stayed normal. Men and women showed similar patterns. Participants were grouped by follow-up health: optimal agers with no disease (35 people), successful agers with two or fewer well-controlled conditions (24 people), and those with poorly controlled disease, mostly cardiovascular (23 people). Fitness fell more in the compromised-health group than the optimal-health group, 24.2% versus 17.3%. Despite these declines, 98.7% of participants who completed the test scored at or above the 90th percentile for peak oxygen consumption compared with reference populations of their age.

The authors frame this as biological aging happening even in bodies protected from the effects of inactivity, since these cyclists kept training for nearly a decade. Peak oxygen consumption reflects how efficiently the heart, lungs and muscles deliver and use oxygen during exertion, and it naturally declines with age as heart output and muscle mass drop. Most health markers looked similar across disease groups, suggesting continued exercise may preserve function even as disease emerges, though the study cannot say exercise caused that preservation.

Peak Oxygen Consumption Fell 19.7% Over 9 Years in Older Cyclists

GeroScience, 2026, Fathi et al.

The authors note potential survivor bias: only 82 of the original 125 cyclists returned, so those who died, became too unwell, or stopped exercising are missing from the data. There was no untrained comparison group, so results describe change within committed exercisers only.

Dr. Axe’s Take

Losing nearly a fifth of peak oxygen capacity over nine years sounds alarming until you see these people were still beating 98.7% of their age group. Cardiorespiratory decline and muscle loss are part of normal aging biology, but the rate is not fixed. I would rather see someone in their 70s losing ground from a high baseline than starting that decade already deconditioned. My advice: keep a weekly rhythm of both endurance work, like cycling or brisk walking, and resistance training to protect lean tissue mass, since this study shows muscle and fitness erode together even in people who never stopped training. Consistency matters more than intensity here.

— Dr. Axe

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Study summary

Who: 82 of 125 original competitive cyclists retested (53 men, 29 women), aged 64 to 86 at follow-up
Design: Nine-year longitudinal follow-up of previously assessed older exercisers, no untrained comparison group
Dose: Continued self-directed cycling exercise over 9 years; no prescribed dose or frequency reported
Primary result: Peak oxygen consumption declined 19.7 percent, from 44.1 to 35.4 ml per kg per minute
Secondary: Lean tissue mass fell 8.1 percent; body fat percentage rose from 23.8 percent to 29.2 percent; fitness declined more in those with compromised health versus optimal health (24.2 percent vs 17.3 percent); 98.7 percent of finishers remained at or above the 90th percentile for age-based fitness norms
Funding / conflicts: Funders listed in the journal record: Aging Biology Foundation EU, Bupa Foundation. Conflict statement in the PubMed record: The authors declare no competing interests.
Date: Sep 28, 2026