The 20 Minute Workout:
1) Pick your favourite cardio exercise: Running, stairs, hills, elliptical machine, rowing machine, bike, speed walking, etc.
2) Warm up for 4 minutes at a comfortable but strong pace (Effort: 7/10)
3) Sprint for 30 seconds (Effort: 10/10)
4) Coast for 90 seconds at an easy, slow pace (Effort: 2/10)
5) Repeat the sprint & coast 6 more times, for a total of 7 intervals
6) Cool down for 2 minutes (Effort: 5/10)
The sprint should be pushing your redline limit. If this is your first time doing intervals, it will take a few tries to figure out how hard you can push.
Don’t be scared of challenging yourself. Exercise only makes you tired in the moment. The after-effects are worth the effort.
If you have limited experience in physical activity please consider consulting a professional trainer or your doctor before undertaking any strenuous activity.
The 20-minute workout challenge:
Perform the each interval workout 3x a week for 2 weeks. Keep the 4-minute warm-up and the 2-minute cool down. Supplement with as much long-distance cardio and outdoor activity as possible.
- 30 seconds sprint, 90 seconds easy pace
- 60 seconds sprint, 60 seconds easy pace
- 90 seconds sprint, 30 seconds easy pace
- 30 seconds sprint, 90 seconds easy pace
- 45 seconds sprint, 75 seconds easy pace
- 75 seconds sprint, 45 seconds easy pace
- 30 seconds sprint, 90 seconds easy pace
Great ways to keep it fun! Track your intervals and see how they progress over time.
More Background for the interested reader:
I love interval training because it is a natural way to stimulate the production of Human Growth Hormone in your body. You will feel perkier and energized for 36-48 hours after a strong interval session.
Although there are many opinions out there about how many minutes of exercise you need every week, I have found that in a time crunched day, 20 minutes of high intensity interval training is sufficient to raise my energy and productivity levels.
I read recently that a group of Canadian scientists have published their findings on how LITTLE exercise is required to be beneficial. Comfortingly, this science backs my empirical findings. The work of these scientists was summarized by leading news organizations, including this from the New York Times:
“Several years ago, the McMasters scientists did test a punishing workout, known as high-intensity interval training, or HIIT, that involved 30 seconds of all-out effort at 100 percent of a person’s maximum heart rate. After six weeks, these lacerating HIIT sessions produced similar physiological changes[2] in the leg muscles of young men as multiple, hour-long sessions per week of steady cycling, even though the HIIT workouts involved about 90 percent less exercise time.
Recognizing, however, that few of us willingly can or will practice such straining all-out effort, the researchers also developed a gentler but still chronologically abbreviated form of HIIT. This modified routine involved one minute of strenuous effort, at about 90 percent of a person’s maximum heart rate (which most of us can estimate, very roughly, by subtracting our age from 220), followed by one minute of easy recovery. The effort and recovery are repeated 10 times, for a total of 20 minutes.[3]”
I’m also inspired regularly by the physiological discoveries made by the middle distance running community.
The sport of middle distance running pioneered the empirical rules and the following science that support the physiological benefit of interval training. According to The Sport Digest interval training in the modern era began with Pavvo Nurmi a “Flying Finn” that loved speed play. Called Fartlek in Finnish, Pavvo and his teammates would alternate high speed sprinting with periods of low speed running. Interval training came into widespread use in the 1970s, when the eastern bloc countries were conducting extensive research on human physiology. You can get incredibly fit in a short period of time. For more info on interval training check out Peter John L Thompson’s overview of interval training from 1970 to present.
When Roger Bannister broke the 4 minute mile, he trained on average 45 minutes a day. Sir Roger Bannister was first interviewed by the American Academy of Achievement on October 27, 2000 in London, England and again on June 7, 2002 in Dublin, Ireland. The following quote from Roger Bannister draws on both interviews.
“So I would tend to take about two hours off to travel to a track, spend about 35 minutes running, but running very hard and then just have a shower, didn’t warm up, didn’t warm down, had a shower, would get something to eat and get back to the hospital by two o’clock. So that was really the pattern for several years with, of course, intervals for traveling to matches and team.“
