Effects Of Six Weeks Of Unilateral High-volume Versus High-intensity Resistance Training On Vastus Lateralis Muscle Morphology In Previously Trained, College-aged Males.
Fox, Carlton D. Medicine & Science in Sports & Exercise: July 2020 - Volume 52 - Issue 7S - p 828
PURPOSE: To compare the effects of high-volume (HV) versus high-intensity (HI) resistance training on vastus lateralis muscle morphology.
METHODS: Resistance trained, college-aged males (n=15) participated in 6 weeks of resistance training in which their legs were randomized to undertake HV and in the contralateral leg HI. Resistance training was undertaken 3 days per week. All participants went through 10 days of deload following the 6 weeks of training. Muscle ultrasound of both vastus lateralis muscles was conducted prior to week 1 of training (T1), 72 hours following the last training bout of week 6 (T2), and 10 days following the last training bout (T3) for muscle thickness, pennation angle, and fascicle length assessments.
RESULTS: There was a significant condition by time effect (p=0.039) for muscle thickness. Post hoc analysis revealed that muscle thickness significantly increased from T1 to T2 (2.7±0.4 cm to 2.9±0.4 cm, p=0.023) in the HV leg, but not in the HI leg. However, there was no difference between conditions at any time point. Furthermore, there were no significant interactions or main effects for pennation angle or fascicle length.
CONCLUSION: HI versus HV training elicits differential effects in vastus lateralis muscle thickness over a 6-week period, albeit neither training modality altered pennation angle or fascicle length.