The effect of warm-up with whole-body vibration vs. cycle ergometry on isokinetic dynamometry

The purpose of this study was to compare the effects of warm-up protocols using either whole-body vibration (WBV) or cycle ergometry (CE) on peak torque at 3 different isokinetic speeds and on fatigue in the knee extension exercise. Twenty-seven recreationally trained (age = 23.59 ± 3.87 years) men (n = 14) and women (n = 13) were tested at 3 different isokinetic speeds (60, 180, 300°·s-1) after either WBV or CE warm-up. The WBV consisted of intermittent bouts of 30 seconds of isometric squats at various degrees of hip and knee flexion for a total of 5 minutes. The CE consisted of 5 minutes of pedaling a cycle ergometer at 65-85% of age-predicted max heart rate. Comparisons between the warm-up conditions were analyzed using repeated measures analysis of variance. For the fatigue comparison, subjects completed 50 continuous concentric knee extensions at 240°·s-1. Means from the first 3 repetitions were compared to means from the final 3 repetitions to establish a fatigue index. Conditions were compared through an independent T-test. No significant (p > 0.05) differences were discovered between warm-up conditions at any speed or on the fatigue index. Means were virtually identical at 60°·s-1 (WBV = 142.14 ± 43.61 ft lb-1; CE = 140.64 ± 42.72 ft lb-1), 180° s-1 (WBV = 93.88 ± 35.18 ft lb-1; CE = 96.36 ± 31.53 ft lb-1), and 300°·s-1 (WBV = 78.36 ± 26.04 ft lb-1; CE = 80.13 ± 26.08), and on fatigue percentage (WBV = 51.14 ± 10.06%; CE = 52.96 ± 9.19%). These data suggest that the more traditional 5-minute cycle ergometer warm-up elicits results comparable to a less common vibration warm-up. The findings of this study are that these modalities are comparable under the tested conditions.