Substitution of parts of aerobic training by resistance training lowers fasting hyperglycemia in individuals with metabolic syndrome

We sought to determine the effects of substituting parts of aerobic training (AT) by resistance training (RT) on metabolic syndrome (MetS) factors. MetS patients (aged 56 +/- 7 years; body mass index 33 +/- 5 kg.m(-2) and 3.9 +/- 0.8 MetS factors) were randomized to undergo 1 of the following isocaloric, 16-week long exercise programs: (i) cycling 4 bouts of 4-min at 90% of maximal heart rate (HRmax) followed by 3 sets of 12 repetitions of 3 lower limb free-weight exercises (high-intensity interval training (HIIT)+RT group; n = 33), (ii) cycling 5 bouts of 4 min at 90% of HRmax (HIIT+HIIT group; n = 33), or (iii) no exercise control group (n = 21). We measured the evolution of all 5 MetS components (z score), cardiorespiratory fitness (maximal oxygen uptake), leg strength and power (leg press 1-repetition maximum (1RM) and countermovement jump (CMJ)), fasting blood glucose (FG), fasting insulin, and insulin resistance (homeostasis model assessment 2). Both training groups improved maximal oxygen uptake similarly (170 +/- 310 and 190 +/- 210 mL O-2.min(-1); P < 0.001) and z score (-0.12 +/- 0.29 and -0.12 +/- 0.31 for HIIT+RT and HIIT+HIIT, respectively; P < 0.02). However, only HIIT+RT improved CMJ (P = 0.002) and leg press 1RM above the HIIT+HIIT group (21% vs 6%; P < 0.001). Furthermore, FG only decreased in the HIIT+RT group (5%; P = 0.026, time x group). Our findings suggest that substitution of part of HIIT by leg RT improves glucose control in MetS individuals. Novelty: Most studies addressing the efficacy of endurance versus resistance training are not matched by energy expenditure. We found that substituting 20% of AT with RT reduces hyperglycemia in MetS individuals. Training recommendations to regain glycemic control in MetS individuals should include resistance training.

Automated summary

The study aimed to investigate the effects of substituting parts of aerobic training (AT) with resistance training (RT) on metabolic syndrome (MetS) factors. Results showed that replacing 20% of AT with RT can improve glucose control and muscle strength in MetS individuals, suggesting that resistance training should be included in exercise recommendations for regaining glycemic control in MetS patients.