Identify the two types of muscle fibers in the human body, and assess the functionality of each.
What will be an ideal response?
The human body has two basic types of muscle fibers: (a) slow-twitch or red fibers and (b) fast-twitch or white fibers. Slow-twitch fibers have a greater capacity for aerobic work. Fast-twitch fibers have a greater capacity for anaerobic work and produce more overall force. The latter are important for quick and powerful movements commonly used in strength-training activities.The proportion of slow- and fast-twitch fibers is determined genetically and consequently varies from one person to another. Nevertheless, training increases the functional capacity of both types of fiber, and more specifically, strength training increases their ability to exert force.During muscular contraction, slow-twitch fibers always are recruited first. As the force and speed of muscle contraction increase, the relative importance of the fast-twitch fibers increases. To activate the fast-twitch fibers, an activity must be intense and powerful.
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A prefix that means other is ________.
Fill in the blank(s) with the appropriate word(s).
_________________ ethics suggests that moral ambiguity exists within society and no behavior is inherently wrong but rather the amount of good the behavior produces determines whether it is morally right.
Fill in the blank(s) with the appropriate word(s).
When Jim and Monica play mixed doubles in tennis, what skill makes Monica especially effective at the net?
A) ?power B) ?agility C) ?speed D) ?reaction time E) ?coordination
Which statement BEST summarizes the association between exercise and improved immunity?
A) Long-term, heavy exercisers get the most gain in immunity versus those who exercise only moderately. B) Moderate-intensity exercise temporarily increases the number of white blood cells, thereby boosting immunity. C) Regular exercise does not have any correlation to a healthy immune system. D) The most significant improvements in immunity are seen when a moderate exerciser begins a more intense exercise program.