Interval training has been used by athletes for over a century, but only recently has it become a mainstream concept for developing overall fitness among athletes, coaches, and fitness enthusiasts. While there are a number of different forms of interval training, the purpose of each is the same—to get the benefits of aerobic training, anaerobic training, and even strength training in a short, intense period of time.
The form of this training endorsed by John Cissik, maximal interval training, or MIT, uses exercise periods with a variety of exercise modes combined with brief bouts of recovery to improve performance and body image among its adherents. Cissik has written 10 books and more than 70 articles on strength and speed training that have been featured in Muscle & Fitness, Iron Man, and track and field and coaching publications. Typically the exercise bouts are performed at a high intensity level, with MIT differing dramatically from traditional steady-state, cardiorespiratory training in which a relatively constant intensity, at or below the lactate threshold, is maintained for the duration of the exercise session.
“The old view of fitness held that long-term aerobic exercise was required to work the heart, lungs, and circulatory system,” Cissik explains. “However, performing interval training has numerous cardiorespiratory benefits similar to traditional aerobic training methods.” The author of Maximal Interval Training, he points to improved ability to consume oxygen, greater ability to transport oxygen to exercising muscles, and an increase in mitochondrial size and density allowing for greater production of energy. In addition to improved cardiorespiratory performance, he details six other benefits of MIT:
- An effective tool for weight loss and weight management. “The old thinking was that to burn fat you should exercise at a low intensity,” Cissik says. “The problem with this line of thinking is that if you exercise at a low intensity, you don't burn as much fat!” While low to moderate intensity, steady-state cardio burns a greater percentage of fat during a workout, the total amount of fat burned, as well as the total caloric expenditure, is significantly greater when using a high-intensity interval training program. Thus, performing MIT may be more beneficial for those attempting to lose weight or maintain a healthy weight than traditional steady-state aerobic training.
- Energy System Development. Also known as ESD, energy system development for explosive- and intermittent-style sports is a benefit associated with MIT. Cissik points out that a substance called ATP, or adenosine triphosphate, fuels movement during exercise or while performing in sports. Three primary energy pathways create ATP, with the one dominating ATP production being dictated by the intensity and duration of the activity, as well as a person's ability to utilize oxygen. Cissik clarifies, “To yield the greatest carryover to performance, the training method selected must reflect the metabolic demands of the sport and challenge the energy systems that supply athletes with fuel during competition.” Therefore, to maximize performance in different sports an athlete should engage in training like MIT, which requires intermittent bouts of high intensity performed over short durations, with brief recovery bouts using active or complete rest.
- Increase in anaerobic enzymes. By stimulating an increase in anaerobic enzymes, MIT allows for greater anaerobic energy turnover and more efficient utilization of lactate as a fuel source during exercise. “This allows athletes to work at a higher intensity for a longer period of time, which provides them with a distinct advantage over the competition,” Cissik stresses. From a physiological standpoint, higher-intensity bouts of training also stimulate explosive muscle fibers (Type II) to a greater extent than traditional steady-state aerobic training. This stimulation helps athletes preserve a larger amount of lean muscle mass tissue, allowing for great force production. Cissik says it may also have benefits for those attempting to manage their weight since this method promotes the preservation of lean mass while stimulating fat loss.
- Variety of modalities and equipment. Users have a vast array of training options with MIT, and are not limited to long-slow distance training or whatever cardio equipment is available at the local gym or health club. Having greater options, such as with calisthenics, repeat sprints, and kettlebells, also helps combat the boredom or monotony many people experience when performing continuous-style cardiorespiratory training. Cissik believes this could potentially improve exercise adherence, self-efficacy, self-esteem, and enjoyment.
- Time-efficiency. In general, MIT sessions last approximately 10 to 20 minutes, including rest periods. As an example, Cissik offers that 15 minutes of intense exercise, performed in as few as six sessions over a two-week period, has been shown to have a positive impact on oxidative capacity during aerobic-based exercise. Furthermore, seven sessions performed over two weeks have been shown to significantly improve fatty acid oxidation during exercise.
- Convenience. Finally, Cissik argues that since MIT does not necessarily require a lot of expensive equipment, a session can be performed practically anywhere, meaning not having time to get to the gym is no longer a barrier for most people. MIT may provide the perfect solution for those individuals with limited time to work out.
In Maximum Interval Training, Cissik teams up with strength and conditioning expert Jay Dawes to provide 147 exercises using nontraditional equipment such as medicine balls, heavy ropes, suspension devices, kettlebells, and sandbags as well as numerous programs for serious strength and conditioning enthusiasts and athletes alike.