Mass is a measure of how much matter an object has. Weight is a measure of how strongly gravity pulls on that matter.
C stress isn't good for you... It can raise blood pressure which is harmful
Hello,
Answer to question 1:
It is very useful to increase your flexibility because it helps your body to move better and stay active. Also you will get less pain from moving a lot if you body stays in shape.
Answer to question 2: Increased flexibility in sports is relay important. It helps the person to stay active and work his/her body. Ex. If your playing foot ball, you know all the plays in the book. Your really good and you work out. Now you stop playing for 5 years. Mostly if you trying foot ball again you will not play the same from 5 years ago.
So Flexibility is very important in everyone daily life to stay healthy and strong.
Hope this helps.