Please choose the correct ending to complete the given sentence: Sports and Fitness: [header] How to do a chest roll [title] Make sure you're stretched and limber. [step] Before doing any gymnastic maneuver, it's imperative that you properly stretch and train your body. Because of the nature of a chest roll, you'll want to pay special attention to your back, neck, and abdomen.

Ending1: While doing a chest roll, make sure to : [substeps] Eat a healthy diet and exercise for at least five days a week. You should also exercise following your day of training to maximize your ability to stretch your fluid muscles and your ability to control movements. Ending2: If you start to see pain or twitching, stop the forward roll immediately. [substeps] Apply some padding at this time to minimize discomfort. Ending3: Get in the habit of keeping your back straight, and prepare for the maneuver. [substeps] Lie on your back on a floor that is pretty flat without your head up. Ending4: [substeps] Attempting a maneuver without proper stretching can cause serious injuries, including dislocations, muscle strains, and spinal injuries. Practice and perfect the form of a gymnastic move (in this case, the chest roll) before attempting to actually do it as a moving maneuver.

Answer format: ending1/ending2/ending3/ending4