Imaginary Chair

Sit next to a wall pretending you are sitting in a chair but with nothing under you and hold your body in that position as much time as you can.

This exercise will work all your legs muscles because your legs muscles you'll be the ones that will support you because the upper ones will be forcing your body to keep in contact with the wall and the lower ones will be holding the rest of your weight.

Details: Be careful with the spot where you're putting your back because you may injury you're back and get spine problems in the future. Use a stopwatch to count how much time do you hold in that position and try to increase your time in each day you try it again.