by Christine on May 13th, 2010
High Intensity Interval Training (also called HIIT) is a type of exercise that involves bursts of high-intensity work followed by low-intensity work. Alternating between high-energy and relatively lower-energy work strengthens your heart by repeatedly elevating the heart rate, slowing it, and repeating the process. This type of workout can be used in any cardiovascular workout – jogging, cycling, stair-stepping, rowing, etc. Anybody can do interval training, regardless of their exercise ability. It’s all about raising your heart rate, so the amount of exertion might differ from person-to-person, but anybody can do it.
If you’re stuck in a weight-loss plateau, adding a few interval workouts will help you blast through it.
Here’s some more geek information: During high intensity workout, the body’s anaerobic system users glycogen (energy) stored in the muscles to fuel the short bursts of activity. Anaerobic metabolism works without oxygen, and the by-product is lactic acid. During high intensity workouts, the lactic acid builds, which means you enter an “oxygen debt.” When you recover after this workout, your heart and lungs work together to replenish the oxygen deficiency and break down the lactic acid. In this phase, the aerobic systems in your body take control, using oxygen to convert stored carbohydrates into energy. (This is why many athletes train in high-altitudes, such as in Colorado. By training in high altitudes they can increase the number of red blood cells, which helps them perform for a longer period of time with little or no fatigue throughout.)
This should sound like magic to your ears, readers!
Interval training has many benefits. It strengthens your heart, replenishes its supply of oxygen, increases your metabolism for 24 hours following your workout, improves your athletic performance, and may even help lower your risk for diabetes by improving insulin action. According to the American College of Sports Medicine, more calories are burned in short, high-intensity exercise.
A recent study of athletes following interval training exercise showed that interval training increased the resting metabolic rate (RMR) for the following 24 hours because of post-exercise oxygen consumption. (Smith 2003) Studies have shown that interval training burns fat effectively and improves athletic performance. For instance, a recent study showed an 8.2 second improvement in 2000m rowing following four weeks of interval training in well-trained rowers. (Driller et al, 2009) Additionally, a study at Laval University in Quebec found that HITT cardio helped trainees lose NINE TIMES more fat than those who trained more traditionally (moderate speed for 20-60 minutes). (bodybuilding.com)
Interval training is a training method used by long-distance runners, sprinters, and football players. In fact, intervals account for 50-75% of total training volume of most athletes. I think the most common place I see athletes do interval training are in the images of boxers. Sure, they stand there and punch a bag. Then they go and jump rope for 2-3 minutes, then return to the punching bag. That’s interval training in action!
To be maximally effective, you should warm up, cycle through the high/low intensity six to ten times, and then follow the workout by a cool-down exercise. Instead of measuring heart-rates, let’s use an intensity-scale. Assume 1=easy and 10=you’re going to fall over dead from exertion. During the low-intensity interval you want to be at a five. During the high-intensity interval you want to be at a 7 or higher.
- This is a great table that shows what your target heart rate should be during low- and high-intensity training. (CLICK HERE)
- If walking is the main crux of your exercise, you can still get intervals in. Try walking briskly for two minutes, followed by one minute of skipping like a silly schoolgirl. The higher (more “air”) you can skip, the better. You may want to consider adding an ankle brace just for some extra support. Repeat until your mile walk is done.
- You can also elevate your heartrate by putting your hands over your head; this increases blood to your heart. So another option would be would be walking briskly for two minutes followed by two minutes of brisk walking with your arms moving like you were doing jumping jacks. You can add some light, 2-pound weights for a little extra gusto.
- Try 60 seconds of intense exercise followed by 75 seconds of rest, repeated for 8-12 cycles. You can use this technique in any exercise (jogging, cycling, rowing, stair-stepping, etc). Try to push yourself beyond Level 7 intensity and into the Level 8 realm.
- Try jumping rope in between whatever your normal exercise is. If you haven’t jumped rope as an adult, it’s going to surprise you, I promise.
To get the best bang for your buck out of interval training, you can change up four variables when designing your interval program:
- Intensity (speed) of work interval
- Duration (distance or time) of work interval
- Duration of rest or recovery interval
- Number of repetitions of each interval
You want to try to get to a maximal heart-rate during your high-intensity workout. Try to aim for 85-100% heart rate reserve.
Smith TP, Coombes JS, Geraghty DP (2003). “Optimising high-intensity treadmill training using the running speed at maximal O(2) uptake and the time for which this can be maintained”. Eur. J. Appl. Physiol. 89 (3-4): 337–43. doi:10.1007/s00421-003-0806-6. PMID 12736843.
Driller, Matthew; Fell, James; Gregory, John; Shing, Cecilia and Williams, Andrew. (2009). The effects of high-intensity interval training in well-trained rowers. International Journal of Sports Physiology and Performance, 4(1)IJSPP
BodyBuilding.com has a great article about incorporating HIIT training into your program, with tweaks for what your long-term goals are (weight loss, muscle-building, etc.) CLICK HERE.