Effects of Physical Activity on Thyroid Stimulating Hormone Levels in Obese Metabolic Syndrome Patients: A Meta-Analysis

Metabolic syndrome is a combination of multiple disorders that predispose an individual to risk of diabetes, obesity, cardiovascular diseases (CVDs), cerebrovascular accidents (CVAs), and insulin- resistance. Hypothyroidism is the most prevalent metabolic disorder causing obesity, followed by hypercortisolism and hypogonadism. Hence, this study aimed to determine the effects of various exercises on thyroid stimulating hormone ( TSH) levels in obese patients with metabolic syndrome. The study conformed to the preferred reporting items for systematic reviews and meta-analysis (PRISMA) standards. The PubMed, Cochrane, Google Scholar, Medline, and Biomed Central databases were searched using the keywords exercise, aerobic, rehabilitation, etabolic syndrome, and thyroid stimulating hormone. Studies in English language published between 2010 and 2021 and that examined the efficacy of physical therapy management with sham treatment on TSH levels in patients with obesity were included. The meta-analysis comprised of 526 patients with metabolic obesity from 10 randomised controlled trials. The analysis revealed that when compared with the control group, exercise had a moderate pooled effect on lowering TSH levels, with an effect size standardised mean difference (SMD) of -0.56 (95% Confidence Interval (CI), -1.09-0.02) estimated using a random effects model, with an I2 of 86.61% (95% CI, 77.31-92.10) in the interventional group. It was concluded that although a pooled moderate effect of training on TSH levels was observed when all the studies were analysed using a continuous measure analysis SMD model, an individual analysis of the studies revealed a mild effect, with many studies also revealing the negative impact of training on TSH levels. Nonetheless, exercise-based intervention strategies are safe and effective as a management strategy for hypothyroidism and obesity due to hypothyroidism.