An appraisal of the SDIR as an estimate of true individual differences in training responsiveness in parallel ‐arm exercise randomized controlled trials

Our review provides a critical appraisal of the SDIR approach, which is a statistical method for estimating individual variability in individual responses to exercise training. In our review, we discuss the assumptions and limitations that limit the application of this approach for exercise randomized controlled trials. AbstractCalculating the standard deviation of individual responses (SDIR) is recommended for estimating the magnitude of individual differences in training responsiveness in parallel ‐arm exercise randomized controlled trials (RCTs). The purpose of this review article is to discuss potential limitations of parallel‐arm exercise RCTs that may confound/complicate the interpretation of the SDIR. To provide context for this discussion, we define the sources of variation that contribute to variability in the observed responses to exercise training and review the assumptions that underlie the interpretation of SDIR as a reflection of true individual differences in training responsiveness. This review also contains two novel analyses: (1) we demonstrate differences in variability in changes in diet and physical activity habits across an intervention period in both exercise and control groups, and (2) we examined participant dropout data from six RCTs and found that significantly (P <  0.001) more participants in control groups (12.8%) dropped out due to dissatisfaction with group assignment compared to exercise groups (3.4%). These novel analyses raise the p...
Source: Physiological Reports - Category: Physiology Authors: Tags: Review Article Source Type: research