Create your own Implied Main Idea Sentence. Always warm up before attempting any strength training exercises. Failure to warm up can cause injuries to cold muscles. Remember to use proper lifting procedures for safety sake. In addition, to avoid harm, make sure that you have a spotter with you if you are using free weights. You can also avoid inuury by working within your limits and avoiding the need to show off. (Adapted from Hahn and Payne, Focus on Health)