Mainly overexertion injuries.
Your computer could get viruses, become slow, or have broken parts if you use it improperly.
They can temporarily, but some if improperly used can cause additional damage.
Chords and notes will clash and it won't sound right.
If you exercise and drink no water you decrease the amount of water in your body. You become dehydrated. This is not healthy.
Kegel exercises are completely safe for a healthy person to do.
There are many different calming exercises a person can do. Most popular exercises are breathing practice, muscle relaxation and mind relaxation.
That depends on the specific medication you're talking about. Some will do very little to someone without the condition they are made for. Some can kill a person if taken improperly. The range of possibilities is just about endless.
the lungs
fat-free milk and milk products and resistance-training exercises
The suffix for improperly is -ly.
Your heart