The warm-up period of the workout is important because it. a. slowly and safely raises heart rate. b. ensures the effectiveness of the workout. c. guarantees an injury-free workout. d. a person exercise for a longer period of time. (i already know c and d are wrong)

A. slowly and safely raises heart rate.

Explanation:

Many people believe that a warm-up period before working out is no needed, but this is absolutely wrong. Warming up the muscles will "adjust" them to exercise, also it will increase your heart rate.

Muscles need oxygen to their function, and they get it trough oxygenated blood. So, raising the heart rate will improve muscles functions, giving them the need oxygen. The result of this is a longer endurance during workout, even prevent muscle cramps.

explanation:

two years ago, when picking flowers in the mountains back of yosemite valley, i found a book. it was blotted and storm-beaten; all of its outer pages were mealy and crumbly. the paper seemed to dissolve like the snow beneath which it had been buried, however; many of the inner pages were well preserved. and although all were more or less stained and torn, whole chapters were easily readable. this is the condition of the great open book of yosemite glaciers today; its granite pages have been torn and blurred by the same storms that wasted the castaway book.two years ago, when picking flowers in the mountains back of yosemite valley; i found a book. it was blotted and storm-beaten, all of its outer pages were mealy and crumbly. the paper seemed to dissolve like the snow beneath which it had been buried, however, many of the inner pages were well preserved. and although all were more or less stained and torn; whole chapters were easily readable. this is the condition of the great open book of yosemite glaciers today, its granite pages have been torn and blurred by the same storms that wasted the castaway book.

Whats the