Strong quads not only support your back but make you surprisingly powerful. You never know when you may need to kick down a door, so it helps to be prepared (cue leg exercises at home). Start off with jump squats, keep your feet shoulder width apart, your back straight, your arms out in front of you and lower yourself down. Instead of straightening up, jump into the air from your squat position. Cool down with a bit of air cycling. Simply lie on your back and pedal in the air for a duration of 10 minutes.