Although he set a British record in the 1500-meter run at the 1952 Olympic games in Helsinki, Roger Bannister was still disappointed. He had failed to win a gold medal for Britain, which was his primary goal. Not to be discouraged, however, Bannister took on a new goal: to break the four-minute barrier for the mile run. Although others had attempted this, thus far even the best runners in the world didn't seem to be able to break that formidable 4-minute barrier. Bannister, a medical student, was aware of concepts such as maximal oxygen intake and anaerobic metabolism. As such, he reasoned that to break the long-standing mile record would require an unusual style of training. He opted on a system known as interval training to accomplish his goal, despite being told that breaking the 4-minute barrier was "beyond human capacity." Bannister did have some precedent in his choice of interval training. The great runner of the past, Paavo Nurmi, "the Flying Finn," had set 22 world track records, and had won 9 gold and 3 silver Olympic medals in 12 Olympic track events. Nurmi, considered one of the greatest runners ever, relied mainly on interval training to get in shape for competition. With the help of his interval workouts, Roger Bannister did what many thought was impossible by breaking the world mile record on May 6, 1954, with a time of 3 minutes, 59.4 seconds. Breaking that record made others realize that the 4-minute mile was within the realm of human performance. Bannister's record was broken 46 days later.
Interval training has long been a favored training mode of world-class athletes, such as Bannister and Nurmi, and is still used today for that purpose. But it may be even more valuable for people looking to prevent cardiovascular disease, diabetes, and lose body fat. While many bodybuilders often express concern about the possible "catabolic" effect of doing aerobic exercise, this is far less of a concern when doing interval training as compared to steady-state aerobics, in which the heart rate is maintained in a specific zone or range based on age and maximal heart rate. In contrast, interval training, as the name implies, involves alternating periods of both high intensity and low intensity, using several bouts during the course of one workout. It's the higher intensity portion of intervals that provides most of the benefits. During such high-intensity spikes, you approach anaerobic metabolism, which differs from the steady-state version that involves only aerobic metabolism. But this difference causes dramatic differences between the two modes of training. Numerous studies show that with interval training, you get far more bang for your metabolic buck, in that you can get all the benefits and more than steady-state or conventional aerobics offers in far less time. This, of course, is good news for all those . . .