Greater glycemic control following low-load, high-repetition resistance exercise compared with moderate-intensity continuous exercise in males and females: a randomized control trial.

Exercise has long been known for its beneficial effects on insulin sensitivity (IS) and glucose handling with both moderate-intensity continuous (MIC) exercise and resistance exercise (RE) inducing beneficial effects. In recent years, low-load high repetition (LLHR) RE has emerged as a strategy to increase muscle mass and strength to levels similar to traditional RE, however the effects of LLHR RE on glucose handling has yet to be investigated. The purpose of this trial was to compare the acute effects of LLHR RE to MIC exercise on post-exercise glycemic control and insulin sensitivity in males and females. Twenty-four (n=12/sex) participants completed acute bouts of MIC exercise (30mins at 65% V̇O2peak) and LLHR (3 circuits, 6 exercises/circuit, 25-35 repetitions/exercise/circuit) matched for time with muscle biopsies immediately pre and post exercise and an oral glucose tolerance test (OGTT) 90 minutes following exercise. Blood glucose concentrations (p=0.002, ηp2=0.37), glucose AUC (p=0.002, ηp2=0.35) and max glucose concentration (p=0.003, ηp2=0.34) were lower during the post exercise OGTT following LLHR RE compared to MIC exercise. There was a main effect of trial on TBC1D1 Ser237 phosphorylation (p=0.04, ηp2=0.19) such that it was greater following MIC exercise compared to LLHR RE. Furthermore, phosphorylated ACC Ser79 increased following MIC exercise with no change following LLHR RE (p<0.001, ηp2=0.50). Phosphorylation of PTEN Ser380 was greater in males than females during LLHR RE (p=0.01, ηp2=0.27). These findings suggest that LLHR RE is a feasible exercise modality to improve post-exercise glycemic control in both males and females. Trial Registration Number: NCT06217679.