Appraising Individual Response of VO2peak Following Exercise Training

Abstract

Enhancements in maximal aerobic capacity (VO2max) resulting from exercise training have garnered attention among individuals focused on exercise performance and well-being. Importantly, improvements in VO2max are associated with a considerable reduction in the risk of all-cause mortality and cardiovascular disease. Concurrently, there is considerable interest surrounding ‘individual response classification’ – comprised of various approaches that improves our understanding of individual changes in performance parameters and/or assesses exercise-induced responses across individual’s or populations. As such, this thesis attempts to address two novel questions pertaining to the field of individual response: i) what is the influence of a supramaximal verification phase during repeat measurement of VO2peak on the typical error (TE) and the response rate following exercise training? and, ii) do individual response classification for surrogate markers of CRF agree with response classification for VO2peak? Our results pertaining to question i) indicated that incorporation of supramaximal verification consistently reduced the standard deviation (SD) of individual response, typical error, and confidence interval widths. However, SDs were statistically similar across exercising and non-exercising groups (p>0.05). Response rates increased when incorporating either one (INCR1 to INCR1+; 24% to 48%, p=0.07) or two (INCR2 to INCR2+; 28% to 48%, p=0.063) supramaximal verification phase(s). Moreover, our results pertaining to question ii) indicated that changes in resting heart rate (RHR) (p=0.02, r2=0.39) and training performance (p=0.02, r2=0.36) significantly correlated with changes in VO2peak. We also observed consistently poor agreement between response classification for VO2peak and surrogate markers of cardiorespiratory fitness (CRF) with classification agreement falling below 60% for all outcomes. Therefore, our findings demonstrate that i) supramaximal verification phase reduced uncertainty when classifying individual VO2peak responses, and ii) response classification of surrogate markers of CRF demonstrate poor agreement between individual changes in VO2peak.