Abstract
Background: Being overweight or obese is associated with increased sympathetic activity and decreased vascular function which increases the cardiovascular risk. Current research has shown that conventional aerobic, resistance, and isometric exercise training has the capacity to elicit improvements in autonomic and cardiovascular function. Recently, exercise with whole-body vibration (WBV) has become of high interest to researchers in the field of exercise physiology due to its beneficial effects on bone mineral density, muscle mass, and muscle strength. Purpose: The purpose of this study was to evaluate the acute and chronic effects of WBV on arterial and cardiac autonomic function in overweight and obese (OV/OB; Body mass index 28.3 ± 0.9 kg/m2) women. Methods: In a cross over design, eight young (21 ± 2 yr) OV/OB women were randomly assigned to either WBV training (WBVT) 3 days per week or 6 weeks of no-exercise (CON). After their assigned treatment period, the subjects underwent a 4 week washout period before beginning their next 6 week treatment period (either WBVT or CON). At the beginning and end of each period, brachial blood pressure (BP), heart rate variability (HRV), augmentation index (AIx), and pulse wave velocity (PWV) were obtained at rest and 3 min after (PE3) a 4 min bout of static squat with WBV at 30 Hz frequency and 1.0 mm amplitude. Maximal strength (1-RM) was assessed for the leg extension exercise. Measurements were repeated 6 week after WBVT and CON. Results: There were significant decreases (p < 0.05) in resting systolic BP (SBP, 8 ± 5 mmHg) and diastolic BP (4 ± 2 mmHg) after WBVT compared with CON (p < 0.05). There were significant decreases (p < 0.05) in heart rate (7 ± 4 bpm), SBP (5 ± 4 mmHg), and mean arterial pressure (7 ± 3 mmHg) at PE3 after WBVT compared with CON (p < 0.05). There was a significant increase (p < 0.01) in 1-RM (12 kg) after WBVT, but not after CON. There were no changes in HRV, AIx, and PWV after both WBVT and CON. Conclusion: These preliminary data indicate that 6 weeks of WBVT elicits reductions in resting and post-exercise BP in overweight-obese women. In addition, lower post-exercise HR suggests that cardiovagal regulation may improve after WBVT. Future research is needed to further evaluate this exercise mode as a potential adjunct treatment for cardiovascular diseases.
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