The effects of swimming training at different temperatures along with cinnamon supplementation on liver enzymes and thyroid hormones in diabetic rats.

Objective: The aim of this study was to investigate the effects of swimming (S) training in water at 5°C (S5C) and 35°C (S35C) along with cinnamon (Cin) supplementationon liver enzymes and thyroid hormones in streptozotocin (STZ(-induced diabetic rats.

Materials and methods: In this experimental trial, 48 diabetic rats (55 mg/kg STZ) were divided into (1) diabetic control (CD), (2) S5C, (3) S5C+Cin, (4) S35C, (5) S35C+Cin and (6) Cin groups.Eight rats were placed in the healthy control (HC) group to evaluate the effects of diabetes induction on the research variables. Swimming training was performed at 5±2°C and 35±2°C for eight weeks, 3 days a week.For Cin supplementation, 200 mg/kg/day of the aqueous extract of cinnamon was dissolved in the animals drinking water. One-way analysis of variance with Tukey's post- hoc test in Graphpad Prism software was used to analyze the findings.

Results: S5C and S35C significantly increased thyroid-stimulating hormone (TSH), and decreased alkaline phosphatase (ALP) and alanine aminotransferase (ALT)(p≤0.05). TSH levels in the S35C group were higher than the S5C group (p≥0.05); ALT levels in the S5C group were lower than the S35C group (p≥0.05). Also, Cin decreased AST and ALT levels (p≥0.05), while S35C+Cin decreased T3, ALP and ALT and S5C+Cin decreased ALP (p≥0.05).

Conclusion: It seems that training at different temperatures and consumption of cinnamon synergistically lead to improvement of liver enzymes and modulation of thyroid hormones. However, the effect of training in cold water and its impact on thyroid hormones is still unknown and needs further research.