Diabetes and Exercise: High Intensity Interval Training

If you would like to increase your fitness level in a short amount of workout time, consider adding high intensity interval training, or HIIT, to your exercise regimen.

HIIT is more doable than its name suggests since it can be modified for different fitness levels and health conditions. Plus, the workouts can be done with all exercise modalities including cycling, walking, swimming, ellipticals, and group exercise classes.

However, before starting HIIT, having a base fitness level that includes consistent aerobic activity for at least 20 minutes, three to five times per week, is recommended by the American College of Sports Medicine.

Work and Recovery Intervals

High intensity interval training is a technique involving all-out bursts of action followed by short recovery periods. The intense intervals range from five seconds to eight minutes; recovery periods vary in length and often involve a low intensity activity.

The intense, or work interval should get your heart pumping at ? 80 percent of its maximal rate—a point where you are exercising “hard” and it’s difficult to carry on a conversation. The recovery interval should be a comfortable activity done at 40 to 50 percent of your estimated maximal heart rate.

Different ratios between the work and recovery intervals can be used. A 1:1 ratio might involve three minutes of high intensity activity followed by three minutes of recovery with low intensity movements. One popular protocol involves a 30 second sprint of hold-nothing-back effort followed by four minutes of a recovery activity—and this combination is repeated three to five times.

You can research different HIIT approaches online - just Google “beginners HIIT” - or talk to an experienced trainer or exercise coach.

HIIT Benefits and Cautions

Though the benefits of HIIT are many individuals with a history of heart disease, smoking, hypertension, diabetes, obesity, or other medical conditions should get an okay from their doctor before giving this exercise a try. Those new to HIIT, whatever their age or fitness level, are wise to modify the intensity of the work interval to suit their current fitness status.

The benefits of HIIT include:

• A decrease in fasting insulin levels, and an increase in insulin sensitivity.
• Decreased blood pressure, increased cardiovascular health.
• Improved cholesterol profiles.
• A reduction in abdominal fat (belly fat), and in subcutaneous fat (just beneath the skin).
• A significant betterment of both aerobic and anaerobic fitness.

The metabolic effects of HIIT, though generally beneficial, are of special concern if you have type 1 or 2 diabetes. Because the body continues to use increased energy for up to two hours after a HIIT workout, you may need to adjust carb intake, insulin doses, and monitor carefully before and after exercising.

HIIT is meant to be part of a well-rounded exercise regimen, and should be performed no more than two or three times each week, doing it more often is counterproductive. Beginners may want to start with just one HIIT workout per week until they feel ready for an increased challenge.

Sources: ACSM; Mercola
Photo credit: terren in Virginia