Did first 100 meter interval session at the track. Walking 100 meters in between. Did 30x100meters or 15 laps. Don't feel too bad. Slightly ravenous.

I knew a guy in the military who says he got down to a 4:05 mile, then just quit running because of money issues. His training was to run 100 meters, walk 100 meters forty times in a row M,W,F. Then jog 5 miles on Tue,Thurs. He didn't seem a braggart. I tried the interval part a few times more than 15 years ago but wasn't able to do it. I would get a sharp pain in my chest. I thought perhaps such exercise was just too much for my bicuspid aortic valve. In retrospect it appears that the combination of heavy bench presses plus such extreme running caused some sort of pleurisy-like issue that cropped up now and then.

Now I don't lift weights though and I managed this run today pretty well. Aiming for the full 40x100 once a week.