They should listen to other music because it can sometimes really relate to a life experience someone’s been through.
Because they help to build up your energy levels and allow you to store energy that you will later quickly burn.
Stretching that is characterized by a "bouncing" action is called
Ballistic stretching.
It helps efficiently to increase your range of motion but is known to create an injury. That's why they tell you NOT to do this specific exercise, unless you have a professional trainer with you that can help you.
Anyways, Good Luck! :)
Cancer. that would be the most proper answer
