This would be my top 3:
1. Sitting down exercises – Sitting down has been considered as one of the most effective exercises for obese people. This is also considered as one of the safest exercises. For overweight people or obese people, you can opt to do sitting up and down exercises that are effective for you. This type of exercise can actually help in building basic muscle strength and lessening fat production. While you are sitting down on your chair, you can do various arm movements and arm raises, you can do leg lifting and back bending or body leaning. These are gentle exercises that will prepare your obese body to do strenuous exercises in the future.
2. Walking exercises – Walking exercises is one of the most common exercises too for obese people. It is best recommended that you do short or long walks for at least thirty minutes every day. If you cannot tolerate doing a thirty-minute walk, then you can adjust it according to your capabilities. You should make sure that you keep yourself comfortable as much as possible. Consider wearing comfortable shoes when walking. It will greatly affect your activity for the day. Wear something that is not too tight and not too loose. You should always bring water with you as to replenish all fluids lost due to sweats. This will keep you hydrated. Always remember to take several breaks so as not to overwhelm your body.
3. Swimming exercises – Swimming exercises are also one of the most effective exercises recommended for obese people. This can be a great alternative for some exercises or activities. Remember that water allows you to feel lesser loads from your body because you become lighter when you are in the water. It actually allows you to get rid of more serious strains and injuries as well. You can do all strokes in the pool and you can move every single part of your body. You can do butterfly stroke, breast stroke, or the freestyle. You can do whatever you wish to do in the water.
From:
http://www.paleodietbest.com/exercises/effective-exercises-for-the-heavy/