I’ve come across some articles lately which suggests intervals training have a higher impact on total work capacity (VO2max), than either longer periods of lower intensity or shorter periods of higher intensity exercise alone. But then runners have known about fartlek training for a long time.

I find it remarkable how big a shovel one needs to dig through the manure of exercise advice. Excess precision is a big failing.

Thanks!

Anaerobic work, because it is coupled with maximal muscle contractions – or close to it, stimulates hypertrophy or muscle growth. Aerobic workouts, especially the lengthy type that triathlon athletes must do to be competitive, are actually catabolic or muscle wasting.

Let me give you an anecdotal example. I recently watched TV highlights the world track and field championships which were held in Japan this summer. I couldn’t help but notice that the sprinters’ bodies were both very low body fat and very high musculature. And the high level of muscle development was general, not just in the legs. On the other hand, the marathon runners, who also had very low body fat levels, had very little muscle development. Many of them, especially the top female competitors, looked like they had just been released from the Auschwitz concentration camp. Sprinters’ training is primarily anaerobic. Marathoner’s training is primarily aerobic.

I understand that there are many factors that enter into this picture. One cannot credit the training methods for the entire difference between marathoners and sprinters. Skinny body type athletes will naturally gravitate to the long distance events while the more powerful, muscular types will naturally gravitate to the sprint events. However, a huge percentage of the difference can be attributed to training.

Why do we see this difference? Maximal muscle contraction workouts, especially when large muscles are involved, stimulate the endocrine system to increase the levels of the various hormones responsible for greater muscle development. Also, after any workout the muscles are low in energy stores; protein breakdown is in high gear which results in catabolism; and protein synthesis has stopped, which means no muscle reconstruction. This catabolic condition will persist for a couple of hours after an anaerobic workout but will last several times longer after a hard endurance or aerobic workout. This condition will eventually reverse to anabolism with proper post-workout and recovery period nutrition. But for the endurance athlete, the recovery is just too slow.

Why is this important for the non-athlete who is just trying to loose weight and increase general fitness? While aerobic exercise is superior at burning fat during the exercise period, what happens during the other 23 hours a day is even more important. The best way to increase the rate that calories are burned during each of those 23 hours is to increase the lean body mass. On the track, that means interval sprints instead of long steady runs. In the weight room that means pushing heavy weight for fewer reps rather than using light weights for more reps. In the pool that means interval sprints where each stroke is producing close to maximal muscle force instead of long periods of steady lap swimming.

Am I suggesting that you should not do any aerobic exercise? Not at all. Increasing your aerobic capacity in important for a number of reasons. I personally try to get three anaerobic workouts and two aerobic workouts in per week. I don’t usually get all five workouts in each week, but that’s a whole other issue …

Since I am a wanna-be strength athlete, I naturally have a bias toward strength training which is primarily anaerobic. When I throw the discus, hammer or other heavy object, or when I toss a sheaf or turn a caber, it’s all anaerobic. That need has led my studies down a road less traveled. Most of the literature out there, including the book you are reviewing, is aimed at endurance athletes because that is where the greater numbers are. Endurance athletes must do a lot of aerobic training to be successful in their sport! The result is that most literature overemphasizes aerobic training. Try putting on a community 5K or 10K run or a triathlon. How many participants will you get? Now try a community 200 meter sprint competition. How many participants will you have this time? Get the point?