Photo by Bev Childress
In our current fast-paced society, it can be easy to get overwhelmed by subpar time management: too many tasks to accomplish and not enough time to do them. When it comes to exercise, not only is finding the time to do it an issue, but also assuring the actual exercise session is result-producing. Anyone who sacrifices time and effort naturally wants to get the most out of it. If you can accomplish something in less time as compared to more – yet obtain similar results – then do it.
In a study in the Journal of Applied Physiology it was discovered that reducing exercise time, but increasing training intensity, produced positive results as compared to lengthier sessions of lower-intensity effort. This mode is known as high-intensity interval training (H.I.I.T.).
In their pilot study
- Eight subjects completed six high-intensity interval exercise sessions over a two-week period.
- Each session consisted of 10 x 60-second intervals on a leg cycle ergometer, at 90% maximal heart rate and with 1:00 rest intervals.
- 30 minutes of very intense exercise per week (within the recommended total of 75 minutes of vigorous exercise per week) improved glucose control and markers of skeletal muscle metabolism in patients with type 2 diabetes.
- The results were consistent with a number of publications within the last few years that demonstrate the benefits of H.I.I.T.
- In addition, they found evidence from the Norwegian HUNT study that just a single weekly bout of high-intensity exercise was found to reduce the risk of cardiovascular disease in both men and women.
- They also noted in other H.I.I.T. studies, subjects appear to tolerate the higher exercise intensity and actually prefer H.I.I.T. over more traditional steady-state continuous exercise (i.e., 40 to 60+ minutes walking on a treadmill).
- It was also found young healthy males reported a perceived “enjoyment” of H.I.I.T. as compared to steady-state continuous exercise even though it had a higher rate of perceived exertion. Likewise, patients with heart failure found H.I.I.T. more motivating than traditional steady-state exercise, which they felt was “quite boring.”
What exactly is H.I.I.T?
- Very intense periods of work (:10 to 2:00) followed by a brief rest period (:10 to 1:00) and repeated for a varied number of bouts (6 to 60).
- A H.I.I.T. session may only involve 8 to 16 minutes of total work time and a total session time (warm up, work/rest periods and cool-down) being only 20 to 25 minutes.
Sample H.I.I.T. workouts
- Elliptical trainer – :30 high-intensity effort, followed by :30 of low effort (recovery) – 20 rounds (total = 20 minutes).
- Squat thrusts – jumping jacks – push ups – pull ups – bicycle crunches performed for :20 each exercise, followed by :15 rest – 5 rounds (total = approximately 15 minutes).
- Shuttle runs – run hard for :10, followed by :20 rest- 40 rounds (total = 20 minutes).
- Versa Climber – 1:30 high-intensity effort, followed by :40 rest – 12 rounds (total 26 minutes).
- Any exercise mode done at high-effort followed by a brief rest and repeated for a number of bouts which results in a time-efficient session.
The Journal of Applied Physiology study also noted that U.S. public health guidelines recommend adults accumulate at least 150 minutes per week of moderate-intensity physical activity or 75 minutes per week of vigorous-intensity physical activity. The percentage of U.S. adults attaining these minimal guidelines is very low. One reason very often cited as an excuse not to exercise is the perceived lack of time.
Do the math: 40 to 60+ minutes of steady-state exercise 1) takes more time, 2) can be boring/monotonous and 3) in reality, doesn’t burn a significant amount of energy.
On the other hand, H.I.I.T. is 1) time-efficient, 2) more enjoyable and 3) equally effective, if not more.
Therefore High Intensity Interval Training is a great way to train less and gain more.