Research in Sport Medicine and Technology

The purpose of this study was the effect of eight weeks of circuit training on the Irisin levels and
the Insulin Resistance Index (HOMA-IR) in overweight women. Materials and Methods: In this study 22
overweight women voluntarily were chosen (Age 26.04±4.43 yrs, BMI 29.35±2.53 kg/m2) and were divided
to two groups of control (n=11) and experimental (n=11). In the experimental group, subjects performed
circuit training for eight weeks and four times per week. Blood sample was taken before and 48 hours after
the last training session. Statistical analysis at the level of P<0.05 was done. Findings: After eight weeks of
training, the level of Irisin in experimental group significantly increased while the HOMA-IR had a
significant reduction (p<0.05). Also Pearson correlation co-efficiency test shows that there is a reverse
relationship between irisin and HOMA-IR (P≤0.05). Conclusion: It appears that circuit training improves
body composition and metabolic disorders such as insulin resistance through Irisin induction in overweight
women.

Vitamin C consumption is important in Iron absorption. Therefore, the purpose of this study was to investigate the effect of acute aerobic activity after two weeks vitamin C supplementation on Iron status and hematological indices in club football players. In this quasi-experimental study, 40 club football players from Khuzestan province were randomly divided into two groups of vitamin C and placebo. Daily and for 14 days, subjects received 400 mg vitamin C in vitamin C group and 400mg dextrose in placebo group. 48 hours after the end of supplementation, a Bruce test was performed. To measure Iron, Ferritin, RBC and Hb levels, four blood samples were taken from the subjects, before and after the supplementation, immediately after and 72 hours after the Bruce test. Repeated measure ANOVA and Two way analysis of variance was used. 2 weeks of vitamin C supplementation showed a significant increase in RBC (p=0.026), Hb (p=0.041), serum Iron (p=0.008) and serum Ferritin (p=0.004) compared to placebo group. After aerobic exhaustive activity, RBC (p=0.034), serum Iron (p=0.023) and Ferritin (p=0.031) in vitamin C group significantly decreases compared to placebo group. After 72 hours of recovery, the vitamin‌ C group showed a significant increase in serum Iron (p=0.036) and Ferritin (p=0.045) compared to placebo group. It seems that two weeks of vitamin C supplementation can improve the serum Iron, Ferritin, RBC and Hb profile of professional footballers before aerobic exhaustive activity and in recovery.