인문학
사회과학
자연과학
공학
의약학
농수해양학
예술체육학
복합학
개인구독
소속 기관이 없으신 경우, 개인 정기구독을 하시면 저렴하게
논문을 무제한 열람 이용할 수 있어요.
지원사업
학술연구/단체지원/교육 등 연구자 활동을 지속하도록 DBpia가 지원하고 있어요.
커뮤니티
연구자들이 자신의 연구와 전문성을 널리 알리고, 새로운 협력의 기회를 만들 수 있는 네트워킹 공간이에요.
초록·키워드
This study investigated the effects of progressively increasing voluntary activation during the stretch phase on force and work production in the stretch-shortening cycle (SSC) of human knee extensors. Fifteen young adults performed SSCs under four stretch activation conditions: passive stretch (ST<sub>0%</sub>-SC), feedback-guided active stretch (ST<sub>40%</sub>-SC and ST<sub>80%</sub>-SC), and maximal effort stretch (ST<sub>100%</sub>-SC). All conditions involved maximal voluntary activation during shortening, followed by a fixed-end contraction at 20°. Outcome measures included joint torque and work, estimated fascicle force and work, vastus lateralis fascicle length and velocity, and quadriceps activation. Compared to passive stretch, active stretch conditions produced greater SSC effects, with no significant differences between ST<sub>80%</sub>-SC and ST<sub>100%</sub>-SC. Fascicle work did not differ significantly across conditions, suggesting a decoupling between joint-level output and fascicle-level contribution. Active stretch primarily enhanced force production during early shortening; however, the SSC effect persisted until mid-to-late shortening (80° to 38°) in ST<sub>80%</sub>-SC. ST<sub>0%</sub>-SC also showed nearly twice the fascicle shortening velocity of other conditions. Following shortening, ST<sub>100%</sub>-SC exhibited greater residual force depression during the isometric phase, despite similar activation. These findings demonstrate that voluntary activation during stretch modulates SSC effect through a complex interplay involving muscle-tendon unit decoupling and history-dependent effects, fascicle dynamics, and tendon compliance.
인공지능 문자 인식 모델을 통해 추출된 텍스트로, 일부 오타나 오류가 포함될 수 있으나 지속적으로 개선 중입니다.
오류를 발견하셨다면 해당 부분을 드래그한 후 ' 를 통해 신고해주세요.
오류를 발견하셨다면 해당 부분을 드래그한 후 ' 를 통해 신고해주세요.