Question
I'm a 29 year old active male.  I exercise frequently including running and consider myself in good health. I have needed to work for prolonged periods of time on my knees during the last two weeks. I would sit on my left leg with the outside of my ankle on the ground. My leg felt like it fell asleep put never seemed to wake up. My leg is numb from above my left ankle to a few inches below my calf, all on the left side of the leg.  I feel no pain. I'm concerned because I have never had this happen before and I really need my health for my job for the next several months. Any advice would be great. Thank you

Answer
My first thought is that you caused a compression injury to the nerve along the side on the lower lateral leg & calf.It should slowly return to normal over several weeks. You can have nerve conduction tests performed to see what's happening if it does not improve.