To optimize your fitness, you really want to develop a comprehensive approach to exercise.
Ideally, you need to do a variety of exercises and avoid doing the same ones all the time as this will lead to a relative tolerance; you will not provide your body with the variety of stresses it needs to continuously adapt, improve, and grow stronger.
The basic idea is that you need to provide your muscles with a wide variety of exercises to keep building them. As a general rule, I recommend including aerobic and anaerobic high intensity exercises, strength training, core exercises, and stretching.
Low impact exercises like yoga also have their place, and I highly recommend walking more each day—ideally somewhere between 7,000 and 10,000 steps each day. This is not your exercise, but non-exercise movement that you also need to stay healthy.
