Research

Mixed

Higher cardiorespiratory fitness (CRF) is inversely associated with all-cause mortality with no observed upper limit of benefit, meaning extreme fitness levels provide greater survival advantages than moderate fitness.

Focus on improving your cardiorespiratory fitness through aerobic exercise. This study shows that higher fitness levels correlate with significantly lower mortality risk, and there is no 'ceiling' where more fitness becomes harmful. Even if you have conditions like hypertension, achieving high fitness levels offers significant survival advantages.

GoodSupportsHIGH confidence
Risk-adjusted all-cause mortality was inversely proportional to cardiorespiratory fitness and was lowest in elite performers... There was no observed upper limit of benefit.
Kyle Mandsager et al. · JAMA Network Open · 2018

Why this rating

Large retrospective cohort (n=122,007) with long follow-up (median 8.4 years) and rigorous statistical adjustment, though observational design limits causal inference.

Source

Association of Cardiorespiratory Fitness With Long-term Mortality Among Adults Undergoing Exercise Treadmill Testing

Kyle Mandsager et al. · JAMA Network Open · 2018

DOI 10.1001/jamanetworkopen.2018.3605

cohort · n=122007Cited 467×
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DOI resolved against Crossref · corpus check 2026-06-10

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