I am a male, 84 year and fairly active. In the past year, my legs seem to be developing a problem. If I sit for long (2 hours) or stand in place for long, I become very unstable on my legs. they just do not move as they should. The pain in my legs and lower torso is fairly severe but not unbearable. My doctor tells me to exercise, but it takes all my energy. Do you have any thoughts of how to improve the condition?