Introduction. Metabolic syndrome is defined as a pathological condition characterized by abdominal obesity, hypertension, dyslipidemia, and impaired glucose tolerance. Insulin resistance is hypothesized to underlie metabolic syndrome. Modern studies, including Mendelian randomization, have demonstrated that muscle strength and muscle mass may play an important role in the mechanisms of insulin resistance. Aim. To establish the relationship between relative upper limb muscle strength and triglyceride/glucose index, and to evaluate the effects of different resistance exercise regimens on alternative measures of insulin resistance in men with metabolic syndrome. Materials and methods. At the first stage of the study, 216 men aged from 25 to 50 years were examined. The relative muscle strength of the upper limbs in the bench press exercise and the triglyceride/glucose index were assessed. At the second stage, a randomized controlled trial was conducted, for which 60 men who met the criteria for metabolic syndrome. Men with metabolic syndrome were divided into three groups: low-intensity strength training with blood flow restriction (n = 20), high-intensity strength training (n = 20), low-intensity strength training without blood flow restriction (n = 20). Training was carried out 2 times a week for 12 weeks. Before and after the study, the triglycerides/glucose index, the ratio of triglycerides to high-density lipoproteins, and the combination of the triglycerides/glucose index with body mass index were assessed. Results and discussion. It was found that the relative muscle strength of the upper limbs was inversely proportional to the triglycerides/glucose index (r = –0.52; p 0.05) in the examined men. After 12 weeks of resistance training, statistically significant reductions in triglyceride/glucose index, triglyceride/high-density lipoprotein ratio, and triglyceride/glucose index/body mass index combination were found for the low-intensity resistance training with blood flow restriction and high-intensity resistance training groups (both, p 0,01). Changes in body composition, an increase in the proportion of muscle fibers I and IIa and a decrease in the proportion of muscle fibers IIx, an increase in the activity of glucose transporters, and a decrease in systemic inflammation are the main potential mechanisms for the beneficial effects of resistance training, including in combination with blood flow restriction, on insulin resistance in men with metabolic syndrome. Conclusion. There is an inverse relationship between muscle strength and triglycerides/glucose index; resistance training is an effective and safe tool for reducing alternative indicators of insulin resistance and can be included in comprehensive correction programs for men with metabolic syndrome.
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