Unveiling whole body vibration squat intensity insight from oxygen consumption and heart rate response

This study explored the effects of training weight and amplitude in whole-body vibration (WBV) on exercise intensity, indicated by oxygen consumption (VO₂) and heart rate. In LOAD-study: ten participants performed squats under non-WBV and WBV (30 Hz 2 mm) conditions at 0%, 40%, and 80% bodyweight (BW). In AMPLITUDE-study: eight participants performed squats under non-WBV, low-amplitude WBV (30 Hz 2 mm), and high-amplitude WBV (30 Hz 4 mm) conditions with 0% and 40%BW. heart rate and VO₂ were continuously recorded. Metabolic equivalents (METs) for WBV squats with 0-40% BW were ~ 3.8-5.3, and ~ 7.3 for 80% BW. LOAD-study presented a significant vibration × training weight interaction effect for in-exercise VO₂ (F = 3.171, P = 0.05, η_p² = 0.105) and post-exercise VO₂ (F = 4.156, P = 0.021, η_p² = 0.133). In-exercise VO₂ of 80%BW squat (P < 0.001) and post-exercise VO₂ of both 40% (P = 0.049) and 80%BW squat (P < 0.001) under WBV were significantly higher than those under non-WBV. AMPLITUDE-study presented no significant amplitude × training weight interaction effect for VO₂ and heart rate (P > 0.05). WBV squats are moderate-to-vigorous intensity exercise. 30 Hz 2 mm WBV is sufficient for evoking superior oxygen consumption during and after exercise under certain training weight, the response of heart rate to WBV was less pronounced. Increasing training weight could elicit greater oxygen consumption and heart rate under WBV condition.