Because most of the time they are not properly warming up the muscles necessary for the physical activity your partaking in.
Answer:
Estimated numbers of new cancer cases and deaths in 2021 (In 2021, there will be an estimated 1.9 million new cancer cases diagnosed and 608,570 cancer deaths in the United States.)
Explanation:
Being Exposed to Radiation. Also, being exposed to harmful Toxins.
To distribute oxygen and blood