The effect of gender on force, muscle activity, and frontal plane knee alignment during maximum eccentric leg-press exercise
- نوع فایل : کتاب
- زبان : انگلیسی
- مؤلف : Michael C. Liebensteiner • Hans-Peter Platzer • Martin Burtscher • Friedrich Hanser • Christian Raschner
- چاپ و سال / کشور: 2011
Description
Purpose To investigate for gender differences during eccentric leg-press exercise. Tears of the anterior cruciate ligament (ACL) are considered to be related to eccentric tasks, altered neuromuscular control (e.g., reduced co-contraction of hamstrings), and increased knee abduction (valgus alignment). Based on these observations and the fact that ACL tears are more common in women, it was hypothesized that men and women differ significantly with regard to key parameters of force, knee stabilization, and muscle activity when exposed to maximum eccentric leg extension. Methods Thirteen women and thirteen men were matched for age and physical activity. They performed maximum isokinetic eccentric leg-pressing against footplates of varied stability. The latter was done because earlier studies had shown that perturbational test conditions might be relevant in respect of ACL injuries. Key parameters of force, frontal plane knee stabilization, and muscle recruitment of significant muscles crossing the knee were recorded. Results The ‘force stabilization deficit’ (difference between maximum forces under normal and perturbed legpressing) did not differ significantly between genders. Likewise, parameters of muscle activity and frontal plane leg stabilization revealed no significant differences between men and women. Conclusion This study is novel, in that gender differences in parameters of force, muscle activity, and leg kinematic were investigated during functional conditions of eccentric leg-pressing. No gender differences were observed in the measured parameters. However, the conclusion should be viewed with caution because the findings concurred with, but also contrasted, previous research in this field. Level of evidence Diagnostic study, Level III.
Knee Surg Sports Traumatol Arthrosc DOI 10.1007/s00167-011-1567-0 Received: 21 February 2011 / Accepted: 23 May 2011
