What is high intensity interval training (HIIT)?

  • HIIT is an interval style workout and involves short bouts of hard exercise, at 85-95% of your maximum effort or RPE 15-17.
  • Each hard bout can be as short as 30 seconds, or as long as 5 minutes.
  • Between each hard bout is an equal or longer bout of active rest. Your active rest should be much easier – aim for 50-70% or your maximum effort or RPE 11-14.
  • The average HIIT workout length is 20 to 30 minutes, not including your warmup and cool down.

Benefits of HIIT

  • Although all forms of cardiovascular exercise show health and fitness benefits; most studies found that HIIT programs showed larger improvements in peak fitness.
  • Studies suggest that HIIT has a positive effect on heart rate recovery. Heart rate recovery is a lesser known indicator of health and mortality in those with known heart disease. In other words; the faster your heart rate returns to resting level after exercise, the better. Heart rate recovery value is not reliable for those who are taking heart rate lowering medications.
  • Other health benefits include: improvements in insulin sensitivity, HbA1c values, HDL cholesterol, triglycerides and resting blood pressure values.
  • HIIT workouts generally require less of a time commitment than steady state exercise sessions.
  • The variety that is found in a HIIT workout can help keep you interested and engaged in exercise.

Precautions

  • HIIT is considered safe for most individuals. Studies have been conducted on individuals with coronary artery disease and heart failure, comparing those who participate in HIIT programs to those participating in traditional steady state exercise. The risk was similar between both groups. Most research done on HIIT in the cardiac population was done within supervised settings and baseline screening was conducted. Please speak with your doctor if you wish to engage in HIIT.
  • Exercise intensity level is subjective. It is important to listen to your body and follow your own targets when participating in HIIT.
  • Do not start a HIIT program if you have had recent changes in your health status, symptoms or medications.
  • It is recommended that you have already been participating in some moderate intensity cardiovascular exercise prior to engaging in HIIT.
  • Follow standard exercise safety guidelines: perform a warmup and cool down with each workout, do not begin a workout if you are experiencing any symptoms. If you develop symptoms during your workout – stop! Seek medical attention if required.

HIIT workout examples

  • Structured interval programs maintain consistent work and rest intervals with the same or similar modality. Example: you may run at a high intensity for 1 minute then walk for 1 minute and repeat this 10 times.
  • Random interval programs will vary the duration of work and rest intervals. The Swedish “fartlek” or “speed play” style workout would be a good example.
  • Cardio-resistance circuit programs alternate between bouts of cardio-based and resistance based exercises. Examples of cardio based exercises are: running on the spot, jumping jacks and skipping. Examples of resistance based exercises are: squats, planks or push ups. In each case you would complete and exercise for a given amount of time, rather than a number of repetitions.
  • TABATA, a specific HIIT interval structure: 20 second work: 10 seconds rest x 8 cycles

Want more information?

  • Speak to an Exercise Therapist.
  • Check out our “What is TABATA” video in the continuing education section of this web-site
  • Check out our “HIIT” videos under the exercise demonstration section of this web-site