Modulation of heart rate variability in CrossFit® practitioners

Abstract

INTRODUCTION: CrossFit® is a type of physical exercise that affects the homeostasis of the body requiring adjustments through the autonomic pathway. Due to its intensity of training there is a modification in vagal tone and cardiovascular physiological adaptations. OBJECTIVE: To verify heart rate variability in CrossFit® practitioners. MATERIALS AND METHODS: Cross-section in CrossFit® practitioners from March to June 2017, aged ?18 years, practice time ?3 months and a frequency ?2 times in the week. Excluded: smokers, pregnant women, self-referenced comorbidities (Diabetes Mellitus, hypertension, cardiorespiratory diseases and thyroid dysfunction), women in the menstrual period, menopause, or those who had difficulty understanding the proposed test. For the measurement of heart rate variability (HRV), the heart rate monitor model V800 heart rate monitor was used for its analysis was KUBIOS HRV version 2.0. Approval of CEP-BAHIANA. 5544. RESULTS: 16 participants were studied, with a mean age of 32.11 ± 6.44 years, 10 men (62.5%). The mean BMI found was 26.39 ± 3.80 kg / m², classifying 9 (56.3%) individuals as overweight and 6 (37.5%) with normal weight. The values obtained from HRV in the time domain: VLF: 1544 (859-3640), LF: 827 (550-2115), HF: 661 (335-1577), LF / HF: 1.18 (0.86-1,8). CONCLUSION: In the studied sample, it was observed that CrossFit® practitioners have a slight predominance of sympathetic activity, especially males and those who practice physical activity five or more times per week.