BACKGROUND: Bodybuilding is a competitive sport that involves structured weightlifting routines and diets. The bulking phase training loads and fluctuations in caloric intake may lead to insufficient recovery and overtraining. The activity of the autonomic nervous system (ANS) plays a pivotal role in the acute and prolonged recovery from exercise and can become impaired by overtraining. Therefore, the purpose of this study was to evaluate resting ANS activity and its recovery following a maximal bout of exercise in natural bodybuilders who are in the offseason phase and compare results to recreationally active individuals. METHODS: 7 recreationally active (RA)(24.6 ± 2.1 yrs, 178.6 ± 9.6 cm, 81.1 ± 10.8 kg) and 8 natural bodybuilders (BB)(21.8 ± 2.9 yrs, 176.6 ± 7.2 cm, 89.3 ± 13.0 kg) volunteered for the study. Participation required one lab visit. Heart Rate Variability (HRV) was measured at rest via electrocardiogram (Finapres, NOVA), in a supine position in a dimly lit room for 10-minutes (PRE). Immediately following, participants underwent a treadmill graded exercise test. Upon completion, HRV was monitored for 45-min and analyzed in five minute segments; PRE, 5-10, 10-15, 15-20, 20-25, 25-30, 30-35, 35-40, and 40-45 minutes via online software Kubios HRV Standard (version 3.5.1) for analysis of: root mean square of successive differences (RMSSD), standard deviation of normal-to-normal sinus beats (SDNN), high frequency (HF), and low frequency (LF). SPSS (version was used, and alpha was set to 0.05. RESULTS: HRV data violated normality and underwent a natural log transformation (ln). A One-Way ANOVA showed no differences for any resting marker of HRV, HR, or HR recovery. No significant differences were observed between PRE, 5-10, 10-15, and 15-20 for any marker of HRV. Significant differences were observed for lnRMSSD at 20-25, 25-30, and 40-45 (p < 0.05), lnSDNN at 20-25, 25-30, 35-40, and 40-45 (p < 0.05), lnHF at 15-20, 20-25, 30-35, and 40-45 (p < 0.05), and lnLF 15-20, 25-30, 30-35, 35-40, and 40-45 (p < 0.05). CONCLUSION: The BB group during off-season training exhibited a depressed HRV recovery following maximal exercise when compared with recreationally trained males.

This document is currently not available here.