Why this stuff works so well.

The following is an excerpt from a longer article by the brilliant Lon Kilgore, PhD. Dr. Kilgore typically leaves the PhD out of his title (another reason I like him). He co-wrote at least one book with Mark Rippetoe on strength.


The Paradox of the Aerobic Fitness Prescription
A Facultative Anaerobe Sucks the Air Out of VO2max
Lon Kilgore
In 1936, Canadian endocrinologist Hans Selye proposed the General Adaptation Syndrome theory, an explanation of how the body responds to injurious and non-injurious stress. Selye proposed that the organism goes through a programmed series of physiologic responses and adaptations to ensure survival when the organism is exposed to the same or similar stress later in the life cycle. In the exercise and fitness sciences, this theory is well accepted but frequently misunderstood and misapplied. The crux of correctly applying Selye’s theory is understanding that a disruption of homeostasis must occur in a physiological system in order for adaptation and fitness improvement to occur in that same system.
One of the most apparent examples of the misuse—or, more precisely, ignorance of the appropriate use—of Selye’s theory can be found on the holy ground of aerobic fitness. The fitness boon was born in the late 60s under the guidance of Jim Fixx and Kenneth Cooper. The idea was, and still is, simple: run a lot and you will be fit and healthy. Over the decades, the mythology of running has firmly entrenched into conventional wisdom the idea that developing aerobic fitness (endurance) requires you to run—run long and run slow. The American College of Sports Medicine (ACSM) recommends 20 to 60 minutes of continuous low-to-moderate intensity aerobic activity in order to develop aerobic fitness. A problem immediately presents itself with this training concept. With low- to moderate-intensity running, the ultimate marker of aerobic fitness, VO2max—the maximum amount of oxygen the body can consume at maximal effort—is not challenged. In the conventional 20- to 60-minute prescription for improving aerobic fitness, the demand for oxygen at the working muscle is met by supply. The name itself says it all: aerobic means "in the presence of oxygen." This means that, by definition, this type of training does not—and cannot—provide a disruption of oxygen homeostasis. With no homeostatic disruption, there can be no adaptation, and no fitness gain.

Training long and slow does not make you fit or fast. Friends don't let friends waste precious time on the treadmill "burning calories."

If you would like the entire article, email me with Kilgore Article as the subject and I'll shoot it to you.