Question

Give an account on length of muscle fibre during muscle contraction.

Answer 1

Muscle contraction is isometric if the muscle tension changes but the muscle length remains the same. Muscle contraction is isotonic if muscle tension remains the same during the contraction. According to the sliding filament theory, the myosin (thick) filaments of muscle fibers slide past the actin (thin) filaments during muscle contraction and the two groups of filaments remain at relatively constant length. Both actin and myosin filaments present in the sarcomeres of muscle fibres creates cross-bridges and slide past one another and creates contraction.