Acute physiological effects of whole body vibration (WBV) on central hemodynamics, muscle oxygenation and oxygen consumption in individuals with chronic spinal cord injury.

PURPOSE: (1) Investigate the acute effects of whole body vibration (WBV) on central hemodynamic responses, muscle oxygenation and oxygen consumption (VO2) in individuals with spinal cord injury (SCI) versus sex, age and activity-matched able-bodied (AB) individuals. (2) Assess the effects of three WBV frequencies on all outcome measures.

METHODS

Eleven males with SCI and 10 AB individuals were recruited. Subjects completed three WBV exercise sessions at 30, 40 and 50 Hz. Heart rate (HR), mean arterial blood pressure (MAP), stroke volume (SV), cardiac output (CO), VO2 and relative changes in oxygenated (Δ[HbMbO2]), deoxygenated (Δ[HHbMb]) and total (Δ[HbMbtot]) heme groups were obtained when VO2 steady state was achieved for: pre-WBV sitting, pre-WBV standing, WBV and post-WBV standing.

RESULTS

Both groups demonstrated small but significant increases in VO2, Δ[HbMbO2] and Δ[HbMbtot]; but the increases were larger in the SCI group. A significant decrease Δ[HHbMb] was observed in the SCI group. No frequency effect was observed.

CONCLUSION

The WBV responses do not appear sufficient to induce cardiovascular benefits in the SCI population. WBV may be helpful for individuals with SCI in improving lower limb peripheral blood flow and coping with orthostatic hypotension symptoms earlier in their rehabilitation programs.