Move Slowly, Don’t Stop, and Carry A Big Stick
Humans evolved over the millennia being physical – survival meant performing consistently varied, relatively low intensity endurance activities such as gathering food, building shelter, tracking animals, and simply moving with the seasons (this was 40,000 years before agriculture appeared). This means that humans developed the physiological need for moving at a low level of exertion for several hours a day.
Occasionally, short-duration outputs of peak power during fights and sprints were required (to chase or flee from an opponent or animal). Rarely, if ever, did man spend any long periods of time with his heart rate significantly elevated as a distance runner might today – just as we can look to those genetic ancestors of ours for answers to our dietary needs (eat plants and animals; do not eat grains or dairy), today we can and should take note of our ancestors’ movement patterns for the exercise component of optimal health.
The Danger of Lengthy “Cardio Sessions” and Aerobics
As a general description, physical efforts two minutes or less are considered anaerobic and those that last more than several minutes are aerobic. An aerobic “cardio” session is defined as spending long periods of time at 75% of your maximum heart rate. The danger of engaging in lengthy aerobic workouts is that it creates a stress response within the body. This can result in chronic damage to the body and less optimal fitness than is commonly believed.
“But I love my 60 minute cardio sessions on the treadmill.”
Our bodies don’t love those lengthy cardio “aerobic” sessions as much as we’d like to think – unfortunately, that kind of training (and thinking) is commonplace in today’s gyms and health clubs.
Lengthy Aerobic Exercise Results In:
- increased cortisol levels (cortisol is the stress hormone)
- increased oxidative damage to your cells
- increased systemic inflammation
- depressed immune system
- muscle breakdown (called muscle wasting)
- decreased fat metabolism
Did you notice that last part about decreased fat metabolism? That’s what comes as a surprise to many people – you can actually burn more fat with short term, high intensity workouts than with long, drawn-out cardio sessions.
The Value of Short Interval, High Intensity (Anaerobic) Exercise:
- burns fat
- builds muscle
- builds endurance or aerobic performance (that comes as a surprise to many endurance athletes), but without the muscle breakdown
- helps improve “strong finishes” in endurance events
What is Interval Training?
Short interval, high intensity workouts consist of alternating periods of high intensity work with rest in repeated timed intervals. Research conducted by Dr. Izumi Tabata from the National Institute of Fitness and Sports in Tokyo, Japan found that an interval training cycle of 20 seconds of maximum intensity exercise, followed by 10 seconds of rest, repeated without pause 8 times for a total of four minutes produced remarkable results. His research showed that high-intensity, intermittent training produced greater aerobic and anaerobic capacity than an hour of endurance exercise. Creating your own Tabata workout for interval training is easy.
How to Create a Short Interval, High Intensity Workout:
- The high intensity phase should be strenuous enough that you are out of breath — typically one to four minutes of exercise at 75 to 85 percent of your maximum heart rate.
- Recovery periods should not last long enough for your pulse to return to its resting rate.
- Pick any type of exercise (running, swimming, recumbent bike, treadmill, elliptical machine, pushups, squats, etc).
- Warm up sufficiently to get your body prepared to perform your workout.
- Select the time intervals and the number of rounds you would like to perform during your workout (e.g. Tabata workout is 20 seconds of work, then 10 seconds of rest for 8 rounds).
- Begin your workout exerting as much effort as possible with each consecutive round of work and get a good sweat on!
How Often Should I Do Short Interval, High Intensity Exercise?
- Short interval, high intensity workouts are recommended to be done at least once per week on top of regular movement every day, weekly strength training, sprinting, and other metabolic conditioning workouts.
Is Short Interval, High Intensity Exercise for Everyone?
- Yes, anyone can do short bursts of intense exercise, although you should start slowly if you’ve never done it before. Also, it’s very important to do a good warm-up beforehand to ensure your body is primed and ready for exercise.
- Yes, interval training is hard work, but the sessions are short and you won’t be bored.
- Interval training is not the only way to exercise, but it is an excellent foundation or for any fitness routine, and a wonderful way to get healthy, lose weight, gain muscle, and…get back to your primal roots!
“You try to stay within the rules for the sake of the game, but you can always turn up the intensity.” - Lawrence Taylor, ex-NFL pro football player