Mixed
Increasing exercise training dose (volume) eliminates cardiorespiratory fitness (CRF) non-response in healthy individuals, with hemoglobin mass being the primary determinant of this improvement.
If you have been exercising consistently for a few weeks and see no improvement in your fitness, do not conclude that you are a 'non-responder.' The research indicates that your current exercise volume is likely too low to trigger the necessary physiological adaptations. To see improvements, you must significantly increase your total exercise time (volume) per week, as higher doses eliminate non-response.
The prevalence of cardiorespiratory fitness (CRF) non-response gradually declines in healthy individuals exercising 60, 120, 180, 240 or 300 min per week for 6 weeks. Following a successive identical 6-week training period but comprising 120 min of additional exercise per week, CRF non-response is universally abolished. The magnitude of CRF improvement is primarily attributed to changes in hemoglobin mass.
Why this rating
Randomized controlled trial with a robust within-subject design (non-responders re-tested at higher dose), though limited to healthy young males.
Source
Refuting the myth of non‐response to exercise training: ‘non‐responders’ do respond to higher dose of training
David Montero et al. · The Journal of Physiology · 2017
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