Combined effects of whole-body vibration and dynamic squats on cardiovascular and salivary biomarker responses in healthy adults

Abstract

This study aimed to investigate the acute effects of combining wholebody vibration with dynamic squats on cardiovascular and salivary biomarker responses in healthy adults. A randomized crossover design was conducted with 20 healthy adults. Each participant underwent three exercise sessions, with a 2-week washout period between each session. The sessions consisted of: (1) whole-body vibration (VB) at 25 Hz for 2 minutes, with an amplitude of 2 mm, and 2 minutes of rest between sets, for a total of 5 sets; (2) dynamic squats (SQ) performed 15 times within 2 minutes, with a 2-minute rest between sets, for a total of 5 sets; and (3) a combination of whole-body VB and SQ (VB+SQ). The cardiovascular variables and salivary biomarkers related to exercise intensity were assessed. Only the VB+SQ session significantly decreased the unstimulated salivary flow rate, and caused greater changes in heart rate, systolic blood pressure, mean arterial pressure, rate-pressure product, and heart rate variability compared to VB or SQ alone. Moreover, the VB+SQ session significantly increased the salivary total protein concentration from 0.56±0.05 mg/mL (baseline) to 0.74± 0.06 mg/mL (postexercise condition) and the salivary alpha-amylase activity from 33.83±5.56 U/mL (baseline) to 63.63 ±12.33 U/mL (postexercise condition) (P <0.05). These changes were recovered at 1-hr postexercise condition. Our findings provide information for designing exercise programs that incorporate VB+SQ to enhance hemodynamic and cardiac autonomic responses in healthy adults and for application during rehabilitation periods.