Thursday, September 27, 2007

September Sprints results

I was skeptical that I could improve my short-interval anaerobic power very much in only 5 weeks, especially at the end of a season where I'd had a fair amount of unstructured short interval work in races and hard group rides. And my 5-week plan didn't include as many sprint intervals as I'd planned to do.

But as the graph below shows, just a few weeks of about two sprint interval sessions per week (8 x 15sec) have resulted in a pretty good uptick in my 30-second, 60-second, and 2-minute max power. I've thought about whether there is another reason for those improvements, but have no other excuse than the sprint intervals. As I've said before, I'm no sprinter, but improvement in those time intervals should help me stay closer to the front in bunch sprints.

Like they say, your body can't do what you don't train it to do, and I've always hated sprint intervals and not done many. I found that the more I did them, the less I disliked them. I think even one sprint interval session a week throughout the season would make a noticeable difference, and they can be done quickly before a longer ride so they don't mess with your schedule very much.

It's also interesting to note that my winter training plan includes L7 (10 to 15-sec sprint) intervals one day per week during the L1-L4 (base) training phase. According to the folks who study this stuff, you can do L7 intervals and if you recover completely between intervals, they won't negatively affect your aerobic adaptation becasue you aren't really stressing your anaerobic metabolism in such a short time, you're just stressing your musculoskeletal systems. But if you try to mix in L5 or L6 intervals during the base training period, your aerobic adaptation will be reduced, so avoid them if possible.

That tells me that the sprint intervals probably aren't helping me through better anaerobic energy system development, but through neurological adaptation. The muscle memory and nerve signal systems are improving, which is the same thing that happens when you start lifting weights after a long layoff and you get big gains in the first few weeks without any muscle growth.