Active skeletal muscles are capable of keeping the global [adenosine triphosphate (ATP)] reasonably constant during exercise, whether it is mild exercise, activating a few motor units, or all-out exercise using a substantial mass of muscle. This could only be accomplished if there were regulatory processes in place not only to replenish ATP as quickly as possible, but also to modulate the rate of ATP use when that rate threatens to exceed the rate of ATP replenishment, a situation that could lead to metabolic catastrophe. This paper proposes that there is a regulatory process or "peripheral governor" that can modulate activation of muscle to avoid metabolic catastrophe. A peripheral governor, working at the cellular level, should be able to reduce the cellular rate of ATP hydrolysis associated with muscle contraction by attenuating activation. This would necessarily cause something we call peripheral fatigue (i.e., reduced contractile response to a given stimulation). There is no doubt that peripheral fatigue occurs. It has been demonstrated in isolated muscles, in muscles in situ with no central nervous system input, and in intact human subjects performing voluntary exercise with small muscle groups or doing whole-body exercise. The regulation of muscle activation is achieved in at least 3 ways (decreasing membrane excitability, inhibiting Ca2+ release through ryanodine receptors, and decreasing the availability of Ca2+ in the sarcoplasmic reticulum), making this a highly redundant control system. The peripheral governor attenuates cellular activation to reduce the metabolic demand, thereby preserving ATP and the integrity of the cell.

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The purpose of this study is to determine the effects of the motivational and instructional self-talk and task complexity on the accuracy of forehand top spin of table tennis in advanced players. The 30 male advanced players were divided into 3 groups (2 experimental and 1 control). The task complexity was determined by color of ball and place of table placement. In other words, sequence sending of the ball were changed after two balls and this trend continues. The keywords for motivational self-talk were "I can do" and " I correctly recognize", and for Instructional self-talk "pay attention" and "Close your paddle". Masters et. al test (2008) was used to measure the accuracy of forehand topspin. After the pre-test, subjects took part in 6 training sessions including 20 trails per session. After 48 hours, they participated in post-test. The data were analyzed by paired-samples t-test, one way ANOVA and Tukey post hoc test. Results showed that there is significant difference between the instructional and motivational self-talk in terms of task complexity. These findings suggested that instructional self-talk is the effective variable in performance of tasks that needs high complex decisions and accuracy.

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