Hi. We can continue after this if you'd like
There are two possibilities here and actually this may be a combination of both
One would be claudication--a problem with the arterial blood flow in your leg.
The other would be a disk problem in your lumbar spine even if you don't have much in the way of back pain. You may have a ruptured disk that's pressing on a nerve root
If you talk to your doctor about this, if I were him I'd get Doppler flow arterial studies of the leg and an MRI of your lumbar spine
If claudication is the problem, walking through the pain can help improve the blood flow but often an arterial bypass is needed.
If the problem is a ruptured disk I'd refer you to a physiatrist--a physical medicine and rehabilitation MD specialist--for a hands-on treatment program that should relieve the pain problem.