I added Advanced Amino to maintain overall muscle strength and to continue muscle-building to support the knee and other joints. At the same time supplementing with advanced Joint Formula and QuickStart. The latter two products, I have used for years with great value, but I'm quite sure to say, that the addition of Advanced Amino seems to really contribute to "stronger joints". I'm a 65 years old woman, active on a farm, working horses and doing woodwork, with no constraints.