and they are freely movable, they could be lipomas, which are benign fatty growths...very common in dogs as they age. Sometimes they need to be removed and sometimes, if their growth is slow, they don't need to be removed.
Heavy Weights Not Needed for Muscle Growthby
Dr. Gabe M.
In the Ontario study, fifteen men were assigned four sets of leg presses with one leg. They were asked to continue to extend and contract their leg muscles until they were exhausted against 30 percent of their 1RM...
FIT TIP / RECOVER FOR GROWTH & HEALTHby
for two or three set on both arms/legs.
* Hip Flexor. Kneel on the floor in a lunge position... of your back leg. To increase the stretch, raise the arm that's on the same side as the back leg overhead...