McCarthy John P, Hunter Gary R, Larson-Meyer D Enette, Bamman Marcas M, Landers Kathleen A, Newcomer Bradley R
Department of Physical Therapy, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
J Strength Cond Res. 2006 Aug;20(3):511-8. doi: 10.1519/17395.1.
The purposes of this study were to (a) determine whether structural differences in triceps surae muscle-tendon complex and walking economy exist between 14 African American and 19 Caucasian sedentary women and (b) determine whether muscle-tendon parameters are associated with walking economy. African American and Caucasian subjects were matched on body weight, height, and body composition. Muscle-tendon parameters were determined by magnetic resonance imaging and walking economy was evaluated at 4.8 km.h(-1). Medial gastrocnemius and total triceps surae muscle shape were different across ethnicity despite no ethnic differences in plantar flexion strength or in maximal cross-sectional area for any triceps surae muscles. African American women had shorter gastrocnemius muscles and longer tendons and performed walking more economically. Tendon length was the only variable related to walking economy. No ethnic differences were observed in walking economy after adjusting for tendon length. Data show gastrocnemius tendon length is related to level walking and longer gastrocnemius tendons may partly explain more economical walking in African American women. These preliminary findings indicate the structure of the muscle-tendon complex could be a factor partially accounting for reported ethnic differences in certain types of athletic-related performance.
（a）确定14名非裔美国久坐女性和19名白人久坐女性的小腿三头肌肌腱复合体结构差异和步行经济性是否存在；（b）确定肌腱参数是否与步行经济性相关。非裔美国人和白人受试者在体重、身高和身体组成方面进行了匹配。通过磁共振成像确定肌腱参数，并在4.8 km·h⁻¹的速度下评估步行经济性。尽管在跖屈力量或任何小腿三头肌的最大横截面积方面不存在种族差异，但不同种族间腓肠肌内侧头和整个小腿三头肌的肌肉形状不同。非裔美国女性的腓肠肌较短、肌腱较长，步行经济性更好。肌腱长度是与步行经济性相关的唯一变量。在调整肌腱长度后，未观察到步行经济性方面的种族差异。数据表明，腓肠肌肌腱长度与平地行走有关，较长的腓肠肌肌腱可能部分解释了非裔美国女性步行经济性更好的原因。这些初步发现表明，肌腱复合体的结构可能是部分解释某些类型运动相关表现中所报道的种族差异的一个因素。
