Lie down in supine position.
Raise your legs up and touch your toes on the floor near your head.
Repeat as many times as possible.
Exercised: abs, lower back, hip flexors, spine, shoulders, upper back
Stand three steps away from a wall.
Lean backwards until your hands touch the wall.
Slowly move your hands down the wall (you will have to keep bending your back) until your head touches the floor. Move your hands back up the wall.
Repeat 5-10 times.
Exercised: all muscles along the spine
Lying leg scissors
Lie in supine position and lift both legs six inches off the floor.
Open your legs wide, then cross them at the knees/ankles.
Repeat 25-100 times. Try also moving legs up/down or forward/backward.
Exercised: upper and lower abs, hip flexors, inner and outer thighs
Sit-ups with knee pull-in
Lie in supine position.
Pull knees in toward your stomach as you sit up, and touch your chest to your thighs.
Return to start. Repeat as many times as possible.
Exercised: upper and lower abs, lower back, hip flexors
Bridge of chairs
Place your head on one chair, and your feet on another.
Hold for at least one minute, with your body kept straight.
Exercised: abs, back, neck
Hold on to a chin-up bar or rings.
Lift your knees as high as possible and round your back.
Lower knees. Repeat as many times as possible.
Exercised: abs, grip
Stand up straight, feet shoulder width apart.
Bend legs at knees until your rear touches your calves.
Try to come back up as fast as possible.
Repeat 25-500 times. Try also jumping.
Exercised: thighs, calves, lower back, chest, lungs