Question

What may account for differences in force production at higher velocities between the three subjects for both concentric and eccentric muscle contractions? What implications does this have for real life actions/movements?

Answer 1

Answer :

Muscle produce force and power by utilizing chemical energy through ATP hydrolysis. During concentric contraction muscle generate less force compared to isometric contraction but consume greater amount of energy .conversly more force is generated and lease energy consumed during eccentric muscle contraction. This relationship between force energy use, and velocity of contractions important implications for understanding muscle efficiency but molecular mechanism underlying this remain poorly understand. Here we use spatially explicit multifilament models of Ca2 + regulated force production within half sarcomere to simulate how force production, energy utilization and number of bound cross bridges affected by dynamic changes in sarcomere length. These computational simulation show that cross bridge binding increased during slow velocity concentric and eccentric contraction compared to isometric contraction.

These data indicate that the efficiency of force production decrease in velocity dependent manner and this behavior sensitive to cross bridge compliance. These findings advance our understanding how cross bridge and myofilament properties underlie velocity dependent changes in contratile efficiency during muscle movement.