If you fully mastered seated leg raises, and can perform the most difficult variation of it at least 20 times – try to increase the load on abdominals, by taking horizontal position. As in plank and push-ups, this will make the exercises more difficult, but more effective. Besides, you won’t even need a stool, but this is one of the advantages of home training – full muscle work without equipment.
What muscles work: rectus and oblique abdominals, psoas muscle, rectus hip muscle.
Performing the exercise: lay on the floor, bend your knees and put straight arms along your body. Take your legs off the floor, bend them in hip joint, so that they were in vertical position (photo 1). Without back bending start to straighten one leg, but don’t put it on the floor at the end (photo 2). After one second pause, get the straight leg to the starting position, straighten the other one at the same time. Repeat for required number of times.
Notice: movement should be smooth and slow, spending about 5 seconds on one leg. You can synchronize your breath with movement: straighten one – inhale, straighten the other one – exhale. Heels must move maximum close to the floor, but not touch it during the whole cycle. Watch your lower back, using your muscles keep it tightened to the floor (or keep small initial bend). You must rise the number of reps to 20 for each leg. If it’s difficult for now – try to periodically put inactive (bent) leg on the floor, but as the muscle strength grows, go back to correct technique. If you are exercising on the hard floor, don’t forget to put something soft under lower back or use gymnastic carpet.
If you have mastered this exercise, try to increase the load, adding arms movement: when straighten one led, move the opposite hand (for right leg – left one and all the way round) behind your head (but keep it in the air) (photo 3). When switching active (straight) leg, switch hand at the same time (describing a half-circle in horizontal or vertical plane). In this kind of exercise you must pay even more attention to lower back, because coordinated moves of arms and legs may cause excessive bends up, as well as to the sides (always keep your muscles tensed to avoid excessive lower back moves).
If you perform all the exercises descripted above, you will prepare your body to the hardest thing (that works on abdominals really intensively) exercise – laying leg raises.
Good books to read:
Bret Contreras. Bodyweight Strength Training Anatomy – Human Kinetics, 2013 – 224 p.
Kavadlo Al. Pushing the Limits: Total Body Strenght with No Equipment – Dragon Door Publications, 2013 – 224 p.
BJ Gaddour. Your Body Is Your Barbell: No Gym. Just Gravity. Build a Leaner, Stronger, More Muscular You in 28 Days – Rodale, 2014 – 288 p.