The Effect of Single Session of Interval Aerobic Exercise on Serum Spexin Levels in Active Young Men

Spexin is a novel peptide which plays a role in the regulation of feeding behavior, body weight, energy metabolism, and long-chain fatty acid uptake into adipocytes. The aim of the current study was investigate the effect of single session of aerobic interval exercise on serum Spexin levels. Eleven active young men
(aged 24±3.63 years, BMI 22.98±2 kg/m2) volunteered for this study. The exercise protocol comprised 2 series of 6×10 s sprinting cycling with maximal effort and 10 min active rest (cycling with intensity 65%–75% HRmax). Blood samples were obtained at fasting state, pre-exercise (30 min after breakfast ~365 kcal), immediately after, and 15, 30, and 45 min after exercise. The repeated measures ANOVA and Bonferroni posthoc test used to evaluate changes of parameters in the different times. The relationship between variables was assessed using the Pearson correlation coefficient. Despite the changing levels of some metabolites such as glucose, insulin, lactate, TG and LDL-C in this study, spexin levels did not change significantly in any time courses of this study (p>0.05). At fasting state and post-exercise, spexin levels not correlated with other metabolites (p>0.05) but in 30 minutes after breakfast (pre-exercise) negatively correlated with TG (r= -0.645,
p=0.032) and during the recovery period, positively correlated with HDL-C (r= +0.357, p=0.041) and negatively correlated with insulin (r= -0.672, p=0.023). It seems that acute exercise-induced negative energy balance in this study may not be sufficient to induce changes in Spexin serum levels.