Research

Mixed

The term 'non-responder' should be restricted to specific organs or physiological functions rather than applied to the whole individual, as exercise-induced adaptation is systemic and a lack of response in one area (e.g., VO2max) does not preclude adaptation in others (e.g., immune function or muscle metabolism).

If you aren't seeing improvements in your main goal (like running faster or lifting heavier), don't assume exercise isn't working for you. Your body is likely adapting in other ways, such as improved immune function, better blood flow, or metabolic health. The 'right' exercise for you might be different from what you are currently doing, so consider adjusting the type or intensity of your training rather than stopping.

GoodQualifiesHIGH confidence
Lack of adaptation or moderate level of adaptation in one organ or one physiological function would not mean that other organs or functions would not benefit from exercise training. ... Hence, the term of non-responders should be used with caution and just referred to a given organ, cell type, molecular signaling, or function.
Zsolt Radák et al. · Frontiers in Physiology · 2022

Why this rating

Based on a review of multiple studies and animal models, though it is a theoretical framework rather than a single clinical trial.

Source

Issues on Trainability

Zsolt Radák et al. · Frontiers in Physiology · 2022

DOI 10.3389/fphys.2021.790196

narrative_reviewCited 8×
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DOI resolved against Crossref · corpus check 2026-06-10

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