Knee raises exercise.
Great exercise for upper abdominal training, if you need to increase tension then you can do this by completing this exercise with straightened legs not bent knees.
Muscles; Abdominal, hip flexors
1. Lay down on the floor, bend your knees at a 60 degrees, keep your feet just off the floor and Keep your arms straight near your body.
2. Move your bend knees towards your chest and raise your hips of the floor so that you make a right angle.
3. Hold it 2 seconds then slowly return in to the starting position. If you find this easy than you can straighten your legs