Lie on your back on the mat. Flex your knee joints to about a 90-degree angle and press one foot against the mat. Stretch the other leg slightly out forward. Your hands are relaxed lying on the mat alongside your body.
From the starting position lift up one leg and your pelvis (your shoulders stay on the mat) to bring it level with your knees and shoulders. The loose leg stays stretched forward throughout the entire lifting movement. From that position return back down the same way but do not touch the mat with your glutes. Return to the starting position only when have done the required number of repetitions. Exhale while going up and inhale while going down. Switch legs and repeat.
Make sure your feet are in the correct position and your knee joint is at the correct angle. Do not go beyond the recommended level when you are in the upper position to avoid lordotic swayback at the waist. Concentrate on breathing, keeping your pelvis in a neutral position and your torso firm throughout the entire movement.
For greater resistance you can prepare a weight and put it on the hip part of your trunk.
Lie on the floor/mat with your knees bent. Lift one leg and support yourself with the hands on your sides.
Slightly lift the toes of the leg that is on the floor and push to the heel to raise your hips as high as possible. Stay in the arched position for 3 to 5 seconds; then slowly lower the hips to the floor.