Besides the exercises that you do in the Goddess Legs Series, are there any other types of lower body training that you do?
I will let you in on a secret. It is quite common for me to train in water. From my Brazilian soccer trainers to my former speed/agility trainer (John Lewis of Energy Fitness), I have spent my fair share of running, jumping, backpedaling and using kickboards in lap pools. The great thing about working out in water is that it provides resistance with little to no pounding on your joints.
Take a look at this Fit Sugar article about the benefits of the pool on your legs, and enjoy episode five of Goddess Legs 3-90.