4 is better than 2

How fast can you run 100 meters all out? The reason I am asking is that I am wondering if your drop in 5 K performance compared to the time when you ran 15:10 is due to biomechanical deterioration or rather the loss of endurance. Your form on the picture looks very good, like you could still run 15:10. Your performance on the uphill leg of Wasatch Back last year is an indicator that you still have good form.

I see 100 meters all out as a fairly reliable test of biomechanics for a distance runner. I think 15.0 is possible with bad biomechanics, but 12.5 would be very challenging even if you have all the fast twitch muscle in the world. But a slow-twitch dominant runner with proper biomechanics can run 12.5.

It did not surprise me that you managed 13.4 in less than ideal conditions. You were also tired from yesterday's workout, and the run this morning. You just proved my suspicion. That picture looked way too good to blame your 5 K speed loss on biomechanics. You did lose a bit, maybe a second per 100 meters in all out speed due to some biomechanical deterioration, but that is not where most of your problem lies. That should only slow you down by no more than 50 seconds in a 5 K, which means you should be running around 16:00 right now. Your college endurance went somewhere.

I would recommend focusing on two things to get it back - mileage and diet.

Thanks Sasha,

I agree, I think most of what I have lost is due to lack of mileage and any decent training in recent years. I am working on nutrition as well - it is coming along well.