Reeves, Neil D. and Narici, MV and Maganaris, CN (2003) Strength training alters the viscoelastic properties of tendons in elderly humans. Muscle and Nerve, 28 (1). pp. 74-81. ISSN 0148-639X
Full text not available from this repository.Abstract
The effect of strength training for 14 weeks on patella tendon viscoelastic properties was investigated in a group of elderly individuals. Participants were assigned to training (age [mean ± SD] 73.6 ± 3.4 years; n = 7) or control (age 66.4 ± 1.7 years; n = 7) groups. Training was performed three times per week and consisted of two series of 10 repetitions of leg-extension and leg-press exercises at 80% of the 5-repetition maximum. Tendon elongation during an isometric knee-extension contraction–relaxation was measured using ultrasonography. Tendon stiffness was calculated from the gradient of the estimated force–elongation relationship and mechanical hysteresis was calculated as the area between loading–unloading curves. Knee-flexor coactivation, estimated from biceps femoris muscle electromyographic activity, was unaltered (P > 0.05) after the training and control periods. No changes (P > 0.05) were observed in stiffness or hysteresis after the control period. In contrast, tendon stiffness increased from 1376 ± 811 to 2256 ± 1476 N.mm−1 (P < 0.01) and hysteresis decreased from 33 ± 5 to 24 ± 4% (P < 0.05), after training. These training-induced adaptations have implications for maximal muscle force, rate of force development, and metabolic cost of locomotion. Muscle Nerve 28: 74–81, 2003