A recent publication in the March 2017 British Journal of Sports Medicine review compared High-Intensity Interval Training (HIIT) vs Medium Continuous Training (MCT). Below is a summary of the findings.
All studies performed the exercise portion of intervals lasting as little as 4 seconds to as long as four minutes of work, while active recovery time varied from as little as 10 seconds to as long as 4.5 minutes.
These studies identify many benefits associated with consistent HIIT training throughout a variety of population groups. They include the following.
- A decrease in total time spent exercising. The largest reason for people saying they don’t exercise is lack of time.
- Even with a decrease in total time, it has proved more effective at improving aerobic capacity.
- It may reduce hunger after exercise as opposed to medium intensity steady rate cardiovascular exercise increasing hunger.
- It reduces risk factors associated with Metabolic Syndrome by:
- Improving blood pressure
- Improving insulin action
- Improving the reduction in body fat
- Reducing disease-related inflammation markers
Though, to play devil’s advocate, there are also some potential pitfalls of HIIT training that you should be aware of.
- The volume of HIIT training exercise is small, however, the actual exercise portion is usually very high intensity.
- Studies have shown that as exercise intensity increases, the pleasure of exercising decreases. This can potentially have a negative influence on compliance and drop out, meaning the exercise may prove difficult to perform consistently for some people.
- While HIIT training can improve many areas associated with chronic disease, there isn’t enough research out there to show it actually reduces the number of deaths.
- Research on running shows there is no association with running faster at 7.6 mph vs running at 6mph on all-cause and cardiovascular disease mortality.
- The risk for injuries has increased in participants who are not physically ready for HIIT.
While HIIT has many advantages, participants should already have a foundation of training under their belts. This foundation should be built from 8 to 12 weeks of consistent moderate cardiovascular activity and basic strength training three times per week. After this adaptation phase, HIIT training can be supplemented one to two days per week. This should be done on a conservative basis to allow the body to adapt to the increase of intensity. Start with only one or two intervals in a session and increase by one or two per week. Remember to train smart and consistently.
For more information on Dedham Health, visit our website.
Guy C., – Fitness and Martial Arts Director at Dedham Health