Please choose the correct ending to complete the given sentence: Sports and Fitness: [header] How to do waist twists [title] Ask your internist if you can do waist twists, especially if you have back problems such as scoliosis. [title] Do two types of waist twists : [step] The first with full spinal rotation, the other with minimal spinal rotation. [title] Know your spinal flexibility limit.

Ending1: [step] In preparation for doing full range waist twists, assess your limits. Stay within those limits as you perform the full range twists. Ending2: [step] Before doing more than two twists, be sure the abs and sides are well aligned. Leave your feet feet hanging down and don't touch the floor. Ending3: [step] Before doing waist twists, you should learn how to do some combination of these. You'll know what lie beam to do (long beam or weight beam) according to the position of your knees. Ending4: [step] While waist twists can improve your posture, this will not be entirely possible as the body will have many static poses at the time. [title] Know whether to be fully straight forward or slightly tilted forward.

Answer format: ending1/ending2/ending3/ending4