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December Fitness Tips

  • Published
  • By Michelle Walker
  • 169th Force Support Squadron

What is High Intensity Interval Training?

High Intensity Interval Training involves alternating between very intense bouts of exercise and low intensity exercise. For example, sprinting for 30 seconds, then walking for 60 seconds is high intensity interval training. HIIT can be used both anaerobically (in the gym with weights) and aerobically with cardio.

HIIT Benefits:
There are a number of great benefits to High Intensity Interval Training besides serious fat burn that include:
· Increased Aerobic Capacity - The amount of oxygen your body can use (oxygen uptake) is increased, so your overall aerobic capacity can increase faster than with low intensity endurance exercise.
· Increased Lactate Threshold - Your ability to handle increased lactic acid buildup in your muscles increases.
· Improved Insulin Sensitivity - Your muscles more readily suck in glucose, instead of the glucose going to your fat stores.
· Anabolic Effect - Some studies show that interval training combined with consuming slightly more calories than you burn creates an anabolic effect, which helps you put on muscle. The opposite occurs with steady state cardio, which for long durations is catabolic.

Sample HIIT Workout:
(NOTE: Interval training should begin with a 3-5 minute warm-up and end with a 3-5 minute cool-down to prevent dizziness, or nausea.)

Here's a sample HIIT workout that's simple, but effective:

30 seconds sprint/fast jog
60 seconds walk/slow jog

I do this HIIT workout all the time on a treadmill, elliptical, or outside.

The duration of "work" is 30 seconds and my "rest" is 60 seconds. The work/rest ratio in this case is 30/60, or 1 to 2. I shoot for 5-10 cycles, depending on the type of cardio I'm doing and if it's right after strength training. The better shape you are in, the higher intensity you can handle and the higher the work/rest ratio. For example, well trained athletes can use a 2 to 1 work /rest ratio, so they are sprinting for 30 seconds and only resting for 15 seconds. That's tough!

Any type of cardio can be used with interval training, but I would caution against running more than a few times per week, because the demands on your metabolic system and joints are significant. For beginners, I recommend the elliptical, which is lower impact. Swimming, jumping rope, cycling etc. can all work well as training modalities.

I rarely go for just a jog unless I just want to clear my head or get a little sweat. Jogging is child's play compared to HIIT, which is substantially more effective to help burn fat in less time and take your body to a MUCH higher fitness level.

Get busy having FUN!!!