The Dose-Response Relationship between High-Intensity Functional Training and Insulin Resistance in a Metabolic Syndrome Cohort.

Literature supports exercise training as a remarkable mechanism for insulin resistance mitigation.  Regarding the exercise prescription within a clinical population, greater improvements in insulin sensitivity will follow greater dose of exercise. However, the optimal dosage of high intensity functional training (HIFT) for an insulin resistance population has not been established. Purpose: To study the effect of different frequencies of HIFT on insulin resistance in a metabolic syndrome (MetS) cohort. Methods: This randomized trial recruited both men and women (n=25) categorized with MetS. Participants were randomized into one of three exercise frequency groups: 1x/week, 2x/week, 3x/week. A twelve-week HIFT exercise training intervention was prescribed to each individual across all three frequency groups. Baseline and post-program measures were taken regarding insulin resistance parameters, body composition, cardiorespiratory fitness, and metabolic blood measures. Results: Following the exercise training intervention, although there was no significant difference (p > .05), there were favorable reductions in HOMA-IR and insulin (IU) across all three groups: HOMA-IR 1x/week 36.1% decrease, HOMA-IR 2x/week 44.4% decrease, HOMA-IR 3x/week 9.7% decrease, insulin (IU) 1x/week 27.0 % decrease, insulin (IU) 2x/week 46.2 % decrease, and insulin (IU) 3x/week 6.0 % decrease. Conclusion: Within an insulin resistance population, low frequency HIFT was more effective (1x and 2x/week) than higher frequency HIFT (3x/week) in improving insulin resistance.