It does not really do anything directly to the muscles - all it does, is flush out the water out of your body, hence the more tight and dense appearance. All it will do to the muscles, is add a bit of hardness, which is also in part a result of the water being flushed out. However, when using it, you need to be careful with the joints, which can get dry and get achy. In such case it would be a very good idea to use a good joint supporting supplement.