Heading to the gym to do this right now! Here I come Go! St. Louis Marathon Relay!! Faster than ever! Seriously, I've ran a full marathon on my own before but now I'm doing a marathon relay and I know I'm the slowest person on our team, which is what happens when it's co-ed and the guys can run 6-7 minute miles no problem. I have to get faster!
The Complete Guide to Interval Training [Infographic]