I'm going to post part of that article here just in case some people don't follow the link because it is a real eye opener:
You’re probably familiar with Dr. Tabata’s famous experiment; I’ve mentioned it before. Tabata had subjects cycle in what has become known as Tabata intervals – eight sets of 20-second intervals of maximum intensity followed by 10 seconds of rest – every weekday for six weeks (abstract). Compared to the subjects’ modest aerobic gains on a traditional 6-week moderate intensity endurance program, the Tabata subjects saw gains in both anaerobic and aerobic capacity. They got better at endurance training without performing classical endurance training, whereas the guys doing moderate intensity endurance training only improved their aerobic capacities.
In a more recent study by Kirsten Burgomaster, two weeks of sprint interval training, for a total of six sessions, were enough to increase muscle oxidative potential (resting muscle glycogen content) and aerobic endurance capacity in trainees. Subjects performed four to seven 30 second “all out” cycling reps, each separated by four minutes of recovery time. VO2 max was not increased, but this strangely didn’t impact or impair their aerobic capacity, which “increased by 100%.” That’s right – just fifteen minutes of actual sprint training was enough to double endurance capacity within two weeks’ time.
Burgomaster wasn’t through, though; in a 2007 study, she discovered that the metabolic adaptations produced by low-volume sprint training are remarkably similar to those produced by traditional endurance training. Two groups of “active but untrained” (that’s a fairly representative demographic, wouldn’t you say?) men and women were given six weeks of either sprint training or endurance training. Sprint training consisted of thrice weekly, four to six rep sessions of 30 second sprints/4.5 minute rests; endurance training consisted of 45-60 minute continuous cycling sessions, five times a week. The sprinters spent about one and a half hours each week (with most of that time spent resting) on the bikes, while the endurance subjects gave up four and a half hours each week (with most of that time spent pedaling). Huge time commitment discrepancy, and yet there was no discernible difference in metabolic outcomes. In fact, the authors conclude that sprint interval training is the more “time-efficient strategy” to obtain the benefits of endurance training. You don’t say.In short, interval training gives you the same aerobic benefit as traditional training, yet also gives you anerobic benefit. To me this says there is absolutely no benefit to hour long runs, when research shows interval training does everything it does, and more.
The 30 second sprint with 4 min rest was interesting, I'll be trying that one tomorrow. 30 seconds of sprinting followed by 4 minutes of book reading sounds like fun to me.
