For the first time since my ACL operation in March, I sprinted today. I think it's going to be great for my anaerobic endurance and weight; I can't say I did spectacularly well at sprinting, however.
When I was preparing for my tournament a fews years ago, my old sensei had me do sprints. I went to a track, jogged about half a mile, and then would sprint for 15 seconds, followed by walking for 30.
The difficulty in doing this is measuring time--even with a stopwatch it's tough when you're sprinting.
So I tried a tip from the book The Ultimate Boxer, and decided I would sprint set distances, rather than for a particular time. One set the book recommends is, after a warmup jog, sprinting 8 200-meter intervals (finish within 30 seconds), followed by a 200-meter jog; then something like 10 100-meter sprints, jogging back to the starting line.
Now the standard high-school track is 400 meters, so 200 meters is half the track. The book's recommended interval workout seemed, for me at 51 and recovering from ACL surgery, more like a goal to aspire to than something I can do now. I was right.
After stretching and a 800-meter warm-up jog, my first couple of 200-yard sprints took longer than 30 seconds, with the consequence that they were more of a run than a sprint by the end of them. And I was too bushed to jog in between. I decided to allow myself to sprint for 30 seconds and stop at that point, regardless of whether I had gone 200 meters, and then to walk to where the next 200-meter sprint would start. I got (I think) five of those done, and my knee began to feel a bit sore--not terrible, but not something I wanted to push to the point of being terrible. So I finished with one 100-meter sprint, then a walk around the track.
Besides there being limits to how well I can sprint, there are limits to how often I can do this. Given that I work a nine-hour day Monday through Friday, and I have a three-hour round-trip commute, I can only do interval sprints on the weekend. Ideally I should be running four days a week and doing interval training three days a week. Unless I became a professional athlete--cue laugh track here--I don't have time for that. My hope is that my interval sprinting will complement the anaerobic nature of the core martial arts classes I'm taking, with bursts of punches and kicks.
Interval sprinting really helped me a lot when I was preparing for the tournament--but at that point I was working from home one day a week, and I could go to the track and do my sprints that day, giving me two times a week.
But even once a week, it can't hurt (unless I hurt my knee), and it will probably help. (Actually, what hurts most now isn't my knee, it's the bottom of my foot due to plantar fasciitis.)