Shapour Jaberzadeh1, Daniel Yeo2, Maryam Zoghi3. 1. Department of Physiotherapy, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, Australia. 2. Physica Devonport Physiotherapy, Devonport, Australia. 3. Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Melbourne, Australia.
Abstract
BACKGROUND: Patellofemoral pain syndrome is an extremely common condition, believed to be caused by altered activation of vastus medialis obliquus (VMO), leading to maltracking of the patella. AIM: This study aimed to investigate the effect of altering knee movement and squat depth on the ratio of VMO and vastus lateralis (VMO : VL) during squat exercises. METHOD: Eighteen (7 male and 11 female) healthy, asymptomatic participants performed semi-squat exercises with three squat depths (20°, 50° and 80° of knee flexion) while following three knee movement paths (neutral, varus or valgus). Normalized VMO : VL ratio from linear envelope surface electromyography was analysed. RESULTS: No significant effect was found for gender (p = 0.87), leg dominance (p = 0.99) or knee position (p = 0.44). A significant effect was found for squat depth (p < 0.001) with both the 50° and 80° squats showing increases in VMO : VL ratio (p = 0.031 and p = 0.028), respectively. The VMO : VL ratio was not influenced by gender, leg dominance or knee position in semi-squat exercises. DISCUSSION AND CONCLUSION: Increases in relative VMO activation did occur in 'deeper' squat depths (50° and 80° knee flexion) compared with the 20° condition. Further research is needed in this area concerning the effects of such exercise modifications on a symptomatic patellofemoral pain syndrome population.
BACKGROUND:Patellofemoral pain syndrome is an extremely common condition, believed to be caused by altered activation of vastus medialis obliquus (VMO), leading to maltracking of the patella. AIM: This study aimed to investigate the effect of altering knee movement and squat depth on the ratio of VMO and vastus lateralis (VMO : VL) during squat exercises. METHOD: Eighteen (7 male and 11 female) healthy, asymptomatic participants performed semi-squat exercises with three squat depths (20°, 50° and 80° of knee flexion) while following three knee movement paths (neutral, varus or valgus). Normalized VMO : VL ratio from linear envelope surface electromyography was analysed. RESULTS: No significant effect was found for gender (p = 0.87), leg dominance (p = 0.99) or knee position (p = 0.44). A significant effect was found for squat depth (p < 0.001) with both the 50° and 80° squats showing increases in VMO : VL ratio (p = 0.031 and p = 0.028), respectively. The VMO : VL ratio was not influenced by gender, leg dominance or knee position in semi-squat exercises. DISCUSSION AND CONCLUSION: Increases in relative VMO activation did occur in 'deeper' squat depths (50° and 80° knee flexion) compared with the 20° condition. Further research is needed in this area concerning the effects of such exercise modifications on a symptomatic patellofemoral pain syndrome population.
Authors: Pablo Monteiro Pereira; João Santos Baptista; Filipe Conceição; Joana Duarte; João Ferraz; José Torres Costa Journal: Int J Environ Res Public Health Date: 2022-07-28 Impact factor: 4.614