Study of aerobic metabolism parameters and heart rate variability and their correlations in elite athletes: a modulatory effect of amaranth oil

Abstract

Oxidative stress (OS) and decreased heart rate variability (HRV) are known to be associated with overtraining in athletes. Therefore it is extremely important to estimate profoundness of OS and efficiency of its correction with easy-to-use noninvasive methods. The impact of oil derived from the amaranth (Amaranthus cruentus L.) seeds (AmO) on some parameters of aerobic metabolism and HRV was studied in elite athletes. Possible mechanisms explaining the relationship between HRV and aerobic metabolism were estimated with correlation analysis. The effects of AmO administration (1 ml of concentrated oil per day for 21 days) were studied in 36 competitive male athletes. Short time ECG records were performed in supine and orthostatic position before and after AmO administration, time and frequency domain HRV parameters were calculated. The activities of catalase, superoxide dismutase, levels of thiobarbituric acid reactive species, oxidative modification proteins (OMP), medium mass molecules, hemoglobin and its ligand forms were determined in blood spectrophotometrically. All athletes were divided into two groups according to total power (TP): group 1 (TP < 5000 ms2, n = 18) and group 2 (TP > 5000 ms2, n = 18). AmO provided activation of aerobic metabolism with improved utilization of lipid peroxidation products and OMP. These metabolic changes were accompanied by improvement in HRV in both groups, more pronounced in group 2. Furthermore, increase in correlations between the studied parameters was found with AmO intake. In our opinion, the noninvasive HRV technology can be used not only for assessment of functional capacity of regulatory mechanisms but also for that of metabolic reserve.