To keep the tendons and the joints in the legs healthy you need to ensure they both keep strong in all forms and smooth in all movements. lie on your back and let a friend move your legs around with you ressisting gently to the movement. This is not a race or a competition so work together so that your legs become strong in all directions. Roll to your stomack and repeat this drill and than do the safe for your mate. Make sure you are aware of your breath and alignement as you work so you too learn to better position yourself so you are stable and free to move as you wish without outside support. Anothe drill you can do but alone is to stand preferably bare foot on the ground and using the natural traction try to move the floor with your feet in oposite directions and than one leg as the other remains relaxed. This is a good drill to learn relaxation and to free your hips and legs.