An important issue in rehabilitation is how to protect the skeletal muscle from immobilization effects, since it is the most changeable tissue amongst the biological tissues and responds to normal or modified demands with morphological and functional adaptations. The objective of this paper was to check the effect of two different swimming load intensities on the morphological properties of the soleus muscle, and if the different degrees of swimming are effective to reverse the process of atrophy caused by immobilization during 15 days. Ten rats, 10±2 weeks were used and divided in 2 groups:G1(immobilization/swimming without overload) and G2 (immobilization/swimming with 10% overload). Within the variable analyzed, when the left limb (submitted to immobilization) was compared with the right limb (not submitted) it was observed: for muscle weight G1=-20.55% (p=0.0344) and G2= -17.02% (p=0.0053); for muscle length G1= -10.66% (p=0.0011) and G2= -6.55% (p=0.1016); for serial sarcomere estimate G1= -14.18% (p=0.0101) and G2= -10.99% (p=0.0043); and sarcomere length G1= 3.51% (p=0.3989) and G2= 5.28% (p=0.1771). It has been concluded that two weeks of remobilization through swimming, with different degrees of overload, were not sufficient to reverse the atrophy process caused by immobilization.
skeletal muscle; serial sarcomere; muscle atrophy; immobilization; exercise
