Active tension in a muscle depends upon which of the following: (A) Number of muscle fibres, (B) Number of motor units recruited, (C) Aerobic capacity of muscle, (D) Action potential amplitude
Answer is B. Active Tension in a muscle depends upon the number of motor units recruited. The greater the number of motor units recruited, the greater will be the active tension. Factors Determining Muscle Tension (Active Tension) Tension developed by each fiber Action potential frequency Fibre length (Length-tension relationship) Fibre length Fatigue Number of active fibers Number of fibers per motor unit Number of active motor units (recruitment) Ref: Vander's Human physiology: The Mechanisms of Body function 11th edition Pgno: 276