The impact of progressive overload on the proportion and frequency of positive cardio-respiratory fitness responders

Abstract

The proportion of individuals whose cardio-respiratory fitness change after endurance training does not exceed the test's measurement error can be 40 %. We determined if progressively increasing treadmill run intensity compared to maintaining the same run intensity, improved the responder proportion to a 6-week 20-minute treadmill training regimen. The intervention response standard deviation method estimated the proportion of responders attributable to progressively increasing run intensity. The mixed-effects model demonstrated V̇O_{2 peak} improved significantly more in the progressive versus constant run intensity group. The proportion of V̇O_{2 peak} responses above the smallest worthwhile change attributable to progressively increasing run intensity was 63.6 %.

Keywords: Cardio-respiratory fitness; Progressive overload; Training response.