Article

OBJECTIVE: To compare in vivo effects of eccentric and concentric calf muscle
training on Achilles tendon stiffness, in subjects without tendinopathy. METHODS:
Thirty-eight recreational athletes completed 6 weeks eccentric (6 males, 13
females, 21.6 +/- 2.2 years) or concentric training (8 males, 11 females, 21.1
+/- 2.0 years). Achilles tendon stiffness, tendon modulus and single-leg jump
height were measured before and after intervention. Exercise adherence was
recorded using a diary. RESULTS: All data are reported as mean +/- SD. Groups
were matched for height and weight but the eccentric training group were more
active at baseline (P < 0.05). Tendon stiffness was higher in the eccentrically
trained group at baseline compared to the concentrically trained group (20.9 +/-
7.3 N/mm v 13.38 +/- 4.66 N/mm; P = 0.001) and decreased significantly after
eccentric training (to 17.2 ( +/- 5.9) N/mm (P = 0.035)). There was no stiffness
change in the concentric group (P = 0.405). Stiffness modulus showed similar
changes to stiffness. An inverse correlation was found between initial, and
subsequent, reduction in stiffness (r = -0.66). Jump height did not change and no
correlation between stiffness change and adherence was observed in either group
(r = 0.01). CONCLUSIONS: Six weeks of eccentric training can alter Achilles
tendon stiffness while a matched concentric programme shows no similar effects.
Studies in patients with Achilles tendinopathy are warranted.

Langue : ANGLAIS