This study was a randomized control trial. The purpose of this study was threefold: 1) to determine if intramuscular temperature (IMt) increases in the semitendinosus (ST) are similar to the vastus lateralis (VL) during standard WBV static squatting; 2) to determine if changes in intramuscular temperature of the hamstrings is different from a standard static semi-squat when undergoing WBV in a static stretching position; and 3) to determine if shorter overall durations as is typically used for stretching protocols (i.e. 5 repetitions of 30s each), will result in IMt increases. Twelve subjects (all males), with tight hamstrings completed this study (age 23.5 ± 1.5 years; body mass 76.3 ± 17.7 kg; height 177.8 ± 15.2 cm). Subjects were randomly assigned to treatment order of three groups: semi squat vibration (SQ), vibration with static stretch (VS), and static stretch only (SS). Subjects reported to the lab 3x, each visit separated by one week to receive all treatments. Each treatment day consisted of baseline temperature measurements in the VL and ST and following each of 2 sets (5x60-second for SQ, 5x30-second for VS and SS, with 30 seconds rest in between reps). Post-hoc comparisons revealed that VL temperature increases were significantly greater from baseline than the hamstrings at all three time periods (p<.0001). There were no significant differences found in ST IMt when comparing 5-minutes of total WBV in the VS condition (both sets of 2.5 minute bouts) to 5-minutes of vibration in the SQ condition (p=1.000), or between VS and SS after 5 minutes (p=.9827). Post-hoc comparisons between SS and VS conditions revealed no significant differences after 2.5 minutes (p=1.000), 5 minutes (p=.8812), and 10-minutes post vibration (p=.9844) in ST or VL (p=1.000, p=.0540, and p=.1815 respectively) temperature. The results of our study show that the ST does not exhibit similar increases in IMt as the VL when performing standard semi-squat WBV training. The IMts seen in the static stretch both with and without vibration seem to suggest that factors other than IMt most likely contribute to flexibility changes seen in prior WBV flexibility studies.



College and Department

Life Sciences; Exercise Sciences



Date Submitted


Document Type





vibration, intramuscular temperature, quadriceps, hamstring