Effects of Different Periodization Strategies of Combined Aerobic and Strength Training on Heart Rate Variability in Older Women.

ABSTRACT:Rodrigues, JAL, Santos, BC, Medeiros, LH, Gonçalves, TCP, and Júnior, CRB. Effects of different periodization strategies of combined aerobic and strength training on heart rate variability in older women. J Strength Cond Res 35(7): 2033-2039, 2021-The preservation of autonomic function has been proposed to be a key determinant of health and longevity. Periodization in combined training (CT) (strength plus aerobic exercise in the same session) might improve autonomic modulation. However, the specific influences of nonperiodized (NP), flexible nonlinear periodized (FNLP), and nonlinear periodized (NLP) strategies of CT on heart rate variability (HRV) are currently unknown. Therefore, we investigated the effects of NP, FNLP, and NLP strategies of CT on HRV in physically active women. In total, 54 physically active older women (61.6 ± 6.3 years) previously engaged in a regular exercise training were randomly allocated into 3 groups: NP, FNLP, and NLP. All the subjects performed 12 weeks of training, 3 times per week, with the sessions divided into aerobic (bicycle or treadmill) and strength exercises. Before and after the exercise training, we examined anthropometric, body composition, and HRV measures (low-frequency [LF], high-frequency [HF], LF/HF, and root mean square successive difference of RR intervals [RMSSD]) during rest, a maximum exercise test, and recovery post-test. Mixed-model measures were used, and statistical significance was set at α = 0.05. The waist circumference reduced only in the NP group (∆ = -2.01%). The RMSSD increased in the NLP (∆ = 76.5%) and LF/HF ratio increased in the FNLP (∆ = 34.51%) during the rest period. There were no differences during the exercise test and recovery after test for LF, HF, LF/HF, or RMSSD. In active women, nonlinear periodization strategies of CT improved one of the cardiovascular health outcomes because HRV is a direct predictor of cardiovascular risk.