Which of the following statements best describes the length-tension relationship of a muscle?
a. The total amount of tension a muscle can develop is related only to the muscle's active tension.
b. During active concentric contraction, maximal tension is developed in the muscle's midrange.
c. During active shortening, no tension is present after all cross-bridges have formed and the myofilaments are overlapping.
d. All of the above answers are correct.
ANS: B
Total muscle tension is made up of active tension (number of cross-bridges formed at the
sarcomere level) and passive elastic tension (state of the parallel elastic elements). Active tension
is greatest at optimal length and equally poor in both the lengthened and shortened ends of the
contractile range. The passive elements are slack in the shortened range and under maximum
tension in the lengthened range.
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