PURPOSES: Squatting activities may be used, within exercise programs, to preserve physical function in older adults. This study characterized the lower-extremity peak joint angles, peak moments, powers, work, impulse, and muscle recruitment patterns (electromyographic; EMG) associated with two types of squatting activities in elders. METHODS: Twenty-two healthy, older adults (ages 70-85) performed three trials each of: 1) a squat to a self-selected depth (normal squat; SQ) and 2) a squat onto a chair with a standardized height of 43.8 cm (chair squat; CSQ). Descending and ascending phase joint kinematics and kinetics were obtained using a motion analysis system and inverse dynamics techniques. Results were averaged across the three trials. A 2 x 2 (activity x phase) ANOVA with repeated measures was used to examine the biomechanical differences among the two activities and phases. EMG temporal characteristics were qualitatively examined. RESULTS: CSQ generated greater hip flexion angles, peak moments, power, and work, whereas SQ generated greater knee and ankle flexion angles, peak moments, power, and work. SQ generated a greater knee extensor impulse, a greater plantar flexor impulse and a greater total support impulse. The EMG temporal patterns were consistent with the kinetic data. CONCLUSIONS: The results suggest that, with older adults, CSQ places greater demand on the hip extensors, whereas SQ places greater demand on the knee extensors and ankle plantar flexors. Clinicians may use these discriminate findings to more effectively target specific lower-extremity muscle groups when prescribing exercise for older adults.
PURPOSES: Squatting activities may be used, within exercise programs, to preserve physical function in older adults. This study characterized the lower-extremity peak joint angles, peak moments, powers, work, impulse, and muscle recruitment patterns (electromyographic; EMG) associated with two types of squatting activities in elders. METHODS: Twenty-two healthy, older adults (ages 70-85) performed three trials each of: 1) a squat to a self-selected depth (normal squat; SQ) and 2) a squat onto a chair with a standardized height of 43.8 cm (chair squat; CSQ). Descending and ascending phase joint kinematics and kinetics were obtained using a motion analysis system and inverse dynamics techniques. Results were averaged across the three trials. A 2 x 2 (activity x phase) ANOVA with repeated measures was used to examine the biomechanical differences among the two activities and phases. EMG temporal characteristics were qualitatively examined. RESULTS:CSQ generated greater hip flexion angles, peak moments, power, and work, whereas SQ generated greater knee and ankle flexion angles, peak moments, power, and work. SQ generated a greater knee extensor impulse, a greater plantar flexor impulse and a greater total support impulse. The EMG temporal patterns were consistent with the kinetic data. CONCLUSIONS: The results suggest that, with older adults, CSQ places greater demand on the hip extensors, whereas SQ places greater demand on the knee extensors and ankle plantar flexors. Clinicians may use these discriminate findings to more effectively target specific lower-extremity muscle groups when prescribing exercise for older adults.
Authors: E A Audenaert; L Vigneron; T Van Hoof; K D'Herde; G van Maele; D Oosterlinck; C Pattyn Journal: Med Biol Eng Comput Date: 2011-07-13 Impact factor: 2.602
Authors: Sean P Flanagan; Man-Ying Wang; Gail A Greendale; Stanley P Azen; George J Salem Journal: J Strength Cond Res Date: 2004-08 Impact factor: 3.775
Authors: Man-Ying Wang; Sean S-Y Yu; Rami Hashish; Sachithra D Samarawickrame; Leslie Kazadi; Gail A Greendale; George Salem Journal: BMC Complement Altern Med Date: 2013-01-09 Impact factor: 3.659
Authors: Giancarlo Cavalli Polesello; Eduardo Hitoshi Tsuge Cinagawa; Paulo Daniel Sousa Santa Cruz; Marcelo Cavalheiro de Queiroz; Cristian Jandrey Borges; Walter Ricioli Junior; Daniel Daniachi; Rodrigo Pereira Guimarães; Emerson Kiyoshi Honda; Nelson Keiske Ono Journal: Rev Bras Ortop Date: 2015-12-08