High Intensity Interval Training

Although significant improvements in endurance performance (and corresponding physiological markers such as VO2max, oxidative muscle enzyme activity, performance to exhaustion) result from endurance training programs, these benefits plateau at a certain point and additional increases in hours of training provide little benefit. To reach the next level of performance, intervals must be added to the training regimen.

What is HIT? A training session consisting of cycles of strenuous exertion for up to 30 seconds followed by a similar rest interval. Repeat 4 or more times. There should be a short warm up as well as a cool down. A HIT session can require as little as 10 minutes.

The original study demonstrating the training advantage of intervals used an HIT approach. Even this brief study (2 weeks) with a total of 6 sessions of four 30 second intervals each was enough to demonstrate the advantages over the comparison group assigned to standard endurance training.

HIT was originally proposed for the highly trained athletes looking for a final performance edge for an upcoming event, it has become synonymous with shortened interval training routines used by all athletes.

HIT is a useful interval regimen for

• the "occasional" athlete who is looking for the health benefits of an exercise program for a minimal time commitment.
• the well trained athlete who has another commitment which will impact his/her ability to train for a few days.
• the athlete who will be on an extended vacation for several weeks and needs a bridge to maintain cardiovascular fitness.

HIT has a place as a tool for those who want to improve or maintain their VO2max but have limited training time. Perhaps it is a vacation or a hectic week at work that eliminates regular training opportunities. For those adopting HIT as an alternative to beginning a more traditional dedicated training program (with specific interval days) an initial burst of improving numbers is likely to plateau earlier (and at a lower level).