Search

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 (30 min 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 min 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. [ABSTRACT FROM AUTHOR]

Interval training has been found to lower glucose concentrations and increase insulin sensitivity in males but not in females, which may be due to inherent sex-based differences in metabolism. Twenty-four (12/sex) participants completed a bout of highintensity interval exercise (HIIE, 10 x 1 min at 90% HRmax) to evaluate whether sex influenced the physiological effects of HIIE on postexercise glycemic control during an oral glucose tolerance test (OGTT). Given that body anthropometrics influence postprandial glucose, data were also expressed as a function of the normalized glucose dose. In addition, we examined whether sex differences in postexercise glycemic control were related to sex differences in muscle metabolism and/or insulin signaling proteins. HIIE increased insulin sensitivity in both sexes as characterized by the Matsuda (P = 0.03, ɳp²= 0.20) and HOMA-IR (P = 0.047, ɳp² = 0.17) indices. HIIE also lowered insulin concentration during the OGTT (P = 0.04, ɳp² = 0.18) as compared with control. When normalized for glucose dose relative to lean mass, glucose area under the curve (AUC) was lower in females than inmales (P < 0.001, ɳp² = 0.47). TBC1D1 Ser237 phosphorylation increased in males, but not in females, postexercise (P = 0.03, ɳp² = 0.19). There was no difference in total insulin signaling protein content, muscle glycogen utilization, or AMPK activation during exercise between the sexes. These findings indicate that when the glucose dose is normalized for differences in body composition glycemic handling is better in females and that an acute bout of HIIE improves insulin sensitivity equally in healthy males and females. [ABSTRACT FROM AUTHOR]

Type 2 diabetes (T2D) risk is lower in females than males. It has been reported that females have greater pancreatic 훽‐cell function than males, which may at least in part contribute to the T2D risk in females. 훽‐cell function is influenced by exercise training; however, previous trials comparing 훽‐cell function between the sexes have not included participants matched for training status. Furthermore, the acute effects of different modes of exercise on 훽‐cell function, and whether sex inherently influences these effects, are largely unexamined. Males and females (12/sex) completed a 120‐min oral glucose tolerance test (OGTT) at rest (CON) and following acute bouts of high‐intensity interval exercise (HIIE), moderate intensity continuous (MIC) exercise, and low‐load high‐repetition (LLHR) resistance exercise to assess whether sex inherently influences baseline and/or post‐exercise pancreatic function in the absence of pathology. We found no sex differences in basal pancreatic 훽‐cell function. Females had greater basal insulin clearance following MIC exercise compared to males (p = 0.01) and males tended to have a higher potentiation ratio following HIIE (p = 0.07). Females also had lower glucose sensitivity following MIC exercise compared to HIIE (p = 0.007) and LLHR (p = 0.003). Insulin clearance during the OGTT was greater following HIIE as compared with CON and MIC exercise (p = 0.02). 2‐H oral glucose insulin sensitivity was greater following LLHR compared to CON (p = 0.01). Acute bouts of different modes of exercise do not differentially influence 훽‐cell function but do influence insulin clearance and insulin sensitivity. Therefore, sex and exercise mode interact to differentially influence insulin clearance and glucose sensitivity. [ABSTRACT FROM AUTHOR]