My normal run routine is a path that’s about 2.2 miles long. I walk about half of it and jog the other half. Over the last couple months I haven’t done any sprinting, but I started back up again a few weeks ago, in part because my Saturday morning running group does some sprinting exercises. Being in that group has also pushed me to start doing “long runs,” which for me right now means 3/4 of a mile. That is, a continuous run (no walking breaks) of 3/4 of a mile.

I weighed in at 246 pounds this morning, and that isn’t “all muscle.” Hah! So, yeah, I’m packing a lot of body fat. It feels to me that losing weight is having the biggest effect on my running right now. There were some easy gains early on as I started getting frequent exercise, but now I think I’m at a balance between needing to improve cardiovascular fitness and not having to propel so much mass around.

When I started running a year ago, I could make it about 100 yards before being out of breath and needing to stop. Foot pain set in a couple months later and I stopped running for a few months. Five Fingers got me back out on the road again. I’ve stepped up my running, and one of the great things about running is that it’s easy to see my progress.

Sprints are cake. I can do four or five short sprints (about 100 yards) before I stop; I think perhaps I’ll push to one more. When I lift weights, I push myself to lift until I can’t physically lift the weight any more. I think lifting to exhaustion is more effective than just pushing a weight around a bit; I’m surprised at the people that go into the gym and pick weights that they obviously have an easy time lifting. I think the stopping point should be physical, not psychological. Five sprints does wear me out a lot, but I’m not sure (now, in hindsight) that there really was no way that my body could do a sixth.

As I understand the physiology, sprinting burns up quickly-available energy sources and forces muscle cells to scavenge for energy. Mitochondria respond to that stress by replicating. To me, that suggests some measure of fitness is tuned on the scale of mitochondria, not on a human scale; that means that the system should respond much faster to stress than my whole body does. For example, it would be very difficult for me to lose more than a pound a day; losing weight is a process that takes months. Could I improve fitness faster? I don’t know, but I’m going to be sprinting tonight.

I use the word “jogging” to mean running at a slow pace. Jogging is a use-it-or-lose-it activity; that is, one jogs to prevent adaptation from fading. If injury prevents you from running or sprinting, then jogging will help keep your fitness up. It’s a crappy way to lose weight, and probably also a poor way to improve fitness, but if you aren’t going to sprint or run it’s better than sitting on the couch. Walking, likewise, is better than sitting down but is an ineffective way to improve fitness. Walking and jogging are also something to do if your fitness is very low and you are just starting to exercise.

Running is between these two extremes; it’s less effective than sprints but more effective than jogging or walking. Running is the “performance” speed: sprints build fitness, and then we test ourselves by running a 5k or 10k or half or full marathon. The common wisdom says to run a few miles every day and do a long run once a week, but the research I’ve seen on Tabata training suggests that intensity (sprints) is more important than volume (running). Given the success that most mainstream runners have with running itself as the training protocol for performance running, it seems that it’s a sufficient challenge to the body to induce adaptation.

I have issues with accepting the common wisdom of running 35 miles a week to train for a marathon, and doing a long run once a week, when that wisdom comes from a community that consumes lectins, phytates, and carbs with reckless abandon, and that insists on wearing giant padded shoes. Sure, if I eat crap and wear pillows on my feet, maybe that standard training protocol works; but I care about my fitness and health. I expect it will be years, if not decades, before any significant study on paleo-friendly training regimens. Until then, I’ll follow what good research I can find.

And that means sprints tonight!