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Anaerobic Interval Training/High Intensity Interval Training


Updated June 25, 2014

Anaerobic Interval Training

What It Is:

Also known as High Intensity Interval Training (HIIT), anaerobic intervals involve going all out during your work intervals. That means shorter intervals at 85 to 100 percent of your maximum heart rate or Level 9-10 on this perceived exertion scale. Your recovery intervals will usually last as long or longer than your work intervals, to allow your body to fully recover for the next interval.

Who It's For: More advanced, experienced exercisers or athletes who want to push their limits, increase fitness and performance and don't mind working at very uncomfortable intensity levels.

How to Do It

  1. Choose any cardio activity - This can work with any machine or activity, as long as you're able to work as hard as you can during work intervals.
  2. Choose the length of your workout - Anaerobic of HIIT workouts are usually shorter because they're so challenging. You might keep this workout at 20-30 minutes, depending on your fitness level and level of exertion.
  3. Choose the length of your work/recovery intervals - Experts generally recommend a 1:2 work to rest ratio, which means your rest interval is twice as long as your work interval. An example would be sprinting for 30 seconds and walking to recover for one minute. If you work at maximum effort, you may need even longer to recover.
  4. Start your workout with a 10 to 15 minute warm up to make sure your body is ready for intense exercise. Follow up with your work and recovery intervals, alternating each for the length of the workout.
  5. End with cool down and stretch.

How Often: High intensity interval training is very challenging and it's easy to overdo it if you do it too often. Most experts recommend this kind of training 1-2 times a week with rest or lighter aerobic workouts in between.

Anaerobic or High Intensity Interval Training Workouts


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