In order for any exercise routine to be effective, you will need to at least do enough number of sets. Repetitions are necessary. However, many people are blinded that doing more means they will get better results. This is wrong. If you do more, you will only cause injury to your muscles and tendons. Also, your muscles will not develop right because they are over stressed. So how many sets should you do? It depends really. When doing crunches for example, 3 sets of 10 counts each should be enough for beginners. As your stamina improves, you can increase the number of sets and counts that you can do. But for the Best Exercise to Lose Weight, it is advisable that you get an instructor. This way, you will know exactly how many sets you need to do for each type of exercise. You will no longer have to do guesswork.