Carolina Holz Nonnenmacher1, Iohana Nunes2, Bruno Monteiro de Moura3, Fernando Diefenthaeler3, Kelly Mônica Marinho E Lima4. 1. Physiotherapy Course, Department of Health Sciences, Federal University of Santa Catarina, Governador Jorge Lacerda, 3201, Araranguá, Santa Catarina, 88906-072, Brazil. carolinaholz10@gmail.com. 2. Post-Graduate Program in Rehabilitation Sciences, Federal University of Santa Catarina, Araranguá, 88906-072, Brazil. 3. Biomechanics Laboratory, Department of Physical Education, Sports Center, Federal University of Santa Catarina, Florianópolis, 88040-900, Brazil. 4. Physiotherapy Course, Department of Health Sciences, Federal University of Santa Catarina, Governador Jorge Lacerda, 3201, Araranguá, Santa Catarina, 88906-072, Brazil.
Abstract
PURPOSE: Verify the acute responses of static stretching (SS) on the rectus femoris (RF), vastus medialis (VM), and vastus lateralis (VL) elasticity and knee/hip range of motion (ROM). Additionally, to investigate if there are consistency among quadriceps muscle elasticity after SS. METHODS: Acute effect of SS on pre-post-intervention design. Thirtheen healthy participants (both genders) proposed for a pre-post experimental design. RF, VM, and VL elasticity (strain ratio, SR) was evaluated bilaterally by ultrasound with quasi-static elastography. Higher SR values refer to more rigid tissues. A SS protocol of 3 series of 30 s was applied at right lower limb. The left lower limb was considered as control group. Also, photogrammetry evaluated the knee/hip ROM. RESULTS: For SR muscle comparisons, VM was lower (less stiff) than VL and RF at pre- and post-SS. For time comparisons, no differences were observed for SR and ROM at pre- and post-SS. However, the effect size of the quadriceps SR at SS lower limb was higher than control. CONCLUSION: Acute effects of SS did not change the quadriceps SR or knee/hip ROM in healthy and active subjects. Non-uniform quadriceps SR are observed (VM < VL and RF) independently of SS. Future studies should consider different protocols, muscles, and populations.
PURPOSE: Verify the acute responses of static stretching (SS) on the rectus femoris (RF), vastus medialis (VM), and vastus lateralis (VL) elasticity and knee/hip range of motion (ROM). Additionally, to investigate if there are consistency among quadriceps muscle elasticity after SS. METHODS: Acute effect of SS on pre-post-intervention design. Thirtheen healthy participants (both genders) proposed for a pre-post experimental design. RF, VM, and VL elasticity (strain ratio, SR) was evaluated bilaterally by ultrasound with quasi-static elastography. Higher SR values refer to more rigid tissues. A SS protocol of 3 series of 30 s was applied at right lower limb. The left lower limb was considered as control group. Also, photogrammetry evaluated the knee/hip ROM. RESULTS: For SR muscle comparisons, VM was lower (less stiff) than VL and RF at pre- and post-SS. For time comparisons, no differences were observed for SR and ROM at pre- and post-SS. However, the effect size of the quadriceps SR at SS lower limb was higher than control. CONCLUSION: Acute effects of SS did not change the quadriceps SR or knee/hip ROM in healthy and active subjects. Non-uniform quadriceps SR are observed (VM < VL and RF) independently of SS. Future studies should consider different protocols, muscles, and populations.