I began working out recently, last Wednesday to be exact, today being Friday of the following week, and tonight I worked my legs out for the first time. I must say it was a vigorous work out. Immediately after working my calves, and for approximately 3 minutes beyond, i had a small soft bubble on my left leg, about 1 inch to the left of the shin, right between the ankle and knee. There was no pain and it felt to the touch almost as if it was filled with air. What could this be? I intend to have a doctor look at it, but as I am in between jobs at the moment, that is going to have to wait a couple of weeks.