PO-265 Acute whole-body vibration increases energy expenditure and skeletal muscle microvascular perfusion

Objective Insulin resistance and cardiometabolic disease are associated with decreased muscle microvascular perfusion which impairs nutrient delivery to the muscle.  Impaired glucose and insulin delivery contributes to lower glucose uptake into the skeletal muscle. Exercise increases muscle microvascular perfusion, however, cardiometabolic disease patients are not always willing or able to undertake regular exercise. Objective: Whole-body vibration (WBV) has previously been shown to increase energy expenditure and limb bulk blood flow, however whether WBV increases skeletal muscle microvascular perfusion is not known.   Methods Methods: Eleven healthy participants (5 males, 6 females; Age: 33 ± 1.9 years) stood on a WBV platform (Galileo Sport, Novotec Medical GmbH, Pforzheim, Germany) for 3 min at 12.5 Hz which was compared to standing without vibration.  Thigh muscle (vastus lateralis) microvascular perfusion was assessed by contrast-enhanced ultrasound (iU22, Philips Medical, North Ryde, NSW, Australia) by infusing Definity® microbubbles (Lantheus Medical Imaging, N. Billeruca, USA) intravenously and measured for 3 min following WBV.  Oxygen consumption (Metamax, Cortex Biophysik GmbH, Leipzig, Germany) was measured while standing prior to WBV and during the third minute of WBV. Results Results: Compared with standing without vibration, 3 min of WBV more than doubled muscle microvascular perfusion (0.73 ± 0.17 vs 2.87 ± 0.81 AI/sec, p<0.05) which remained elevated above baseline for 3 min after cessation of WBV. Oxygen consumption modestly but significantly increased while undergoing WBV (282 ± 0.013 vs 419 ± 0.023 mL/min, p<0.05). Conclusions Conclusion: This is the first study to show that WBV significantly increases muscle microvascular perfusion in healthy adults.  We are currently undertaking studies to determine if this WBV may be of benefit in populations with impaired microvascular perfusion, such as type 2 diabetes, for improving cardiometabolic health.