Effects of Multidirectional Vibrations Delivered in a Horizontal Position (Andullation(®)) on Blood Microcirculation in Laboratory Animals: A Preliminary Study

BACKGROUND: A whole-body vibration technique delivered in a horizontal position through a massage mattress was introduced in 2007. The present study analyzed the effects of different exposure periods to these vibrations on microcirculation of mice. MATERIAL/METHODS: Different periods of vibrations (30Hz) were locally delivered in a horizontal position on the external abdominal skin in 3 randomized groups of mice (N=42). The 3 groups receiving vibrations were compared to an untreated control group (N=14). The 3 experimental groups received 3, 6, and 10 min of vibrations. The in vivo measurement of the arterial and venous diameters was done before and after each vibration period. RESULTS: Average venous diameters (μm) after 6 to 10 min of vibrations were significantly increased (7% and 12%, p values 0.026 and 0.013, respectively), but 3 min did not significantly change average venous diameters. Arterial diameters (μm) did not significantly vary after 3, 6, and 10 min. In the control group, variations of arterial and venous diameters during 10 min were not significant. CONCLUSIONS: This study shows a vasodilatory effect of low-frequency vibrations. The hypothesis of local cutaneous blood flow increase is retained. A phenomenon of shear stress of the endothelium induced by skin massage generates this local venous vasodilation and blood flow increase.