Benefits of High Intensity Training

Benefits of HIT - High Intensity Training

Exercise intensity or the amount of work done during exercise is usually customarily divided into four levels depending upon the maximal heart rate (MHR) achieved, and the percentage of carbohydrates and fat burned. Low intensity exercises, which are usually up to 80% MHR, are used to improve general fitness by increasing the muscles’ efficiency in using oxygen in the blood. Medium intensity exercises, which range from 80-85% MHR, improve the body’s anaerobic threshold. High intensity exercises which reach >90% MHR are used to strengthen the heart and improve the body’s anaerobic capacity.

What is HIT?

High intensity training involves exercise regimens that attempt to reach over 90% of the MHR. These are known to be very painful due to the rapid buildup of lactic acid and can result into higher tolerance to lactic acid. These exercises are generally performed with high to maximal intensity in short durations with emphasis on rest and recovery. It is believed that these HIT is superior to other regimens in terms of building strength and muscle size. In a recent study done in McMaster University in Canada, it was shown that HIT was just as effective in improving muscles as with conventional long duration exercises. Their results suggest that it is possible to achieve more by doing less. The exact mechanism for the effectiveness of HIT is still a mystery but it is believed that it stimulates the same cellular pathways that result in the beneficial effects comparable to that of endurance training. It is also hypothesized that HIT can be beneficial not only to already healthy individuals but also to the less fit, overweight, elderly, and those with metabolic diseases.

HIT Programs

HIT programs go against the traditional notion that longer exercises are better. There are a number of HIT programs but their bottom lines are the same: fewer repetitions at high intensity. They rely on the body’s natural adaptive responses. In order to elicit maximal muscle hypertrophy, the body should be led to believe that it needs increased musculature by training the body at 100% intensity. Of course, it would be impossible to sustain maximal effort for long periods but it is enough to result into larger and more efficient muscles.

Various bodybuilders such as former Mr Universe Mike Mentzer used a variation of HIT called the “rest-pause” routine which involved single-rep maximums with 10-second rest intervals. A cadence HIT may follow a 3-1-4-1 count per repetition. This means that 1 rep is composed of 3-seconds exertion, followed by a 1-second maximal contraction, then a 4-second return to starting position (negative movement), and ends with a 1-second rest period. Cardio-HIT programs may involve 10 minutes of HIT, 25 minutes of regular cardio, and 10 minutes of HIT. The HIT periods may involve 15 second sprints followed by 45-second jogging intervals within the 10-minute HIT period. This program reaps the benefits of both anaerobic and aerobic exercises.

Is Tabata HIT?

The Tabata Protocol is a 4-minute program that easily falls under the HIT category. It is known to be the one of the most intense HIT programs and with the shortest duration at only 4 minutes. It was developed by Izumi Tabata, former researcher at Japan’s National Institute of Fitness and Sports. It was based on the training routine employed by the Japanese speed skating team which involved maximal sprinting for 20 seconds and 10 seconds of rest which was repeated 6-8 times in 4 minutes. Needless to say, the Tabata routine was based on the routine employed by world class athletes.

Although it lasts for only 4 minutes, the high intensity intervals used result in what is known as the “after burn effect” where the body continues to burn calories hours after the actual exercise. This is due to the depletion of glycogen during the high intensity exercises which result in the body burning the fat instead while it replenishes the body’s glycogen stores. It is superior to moderate intensity cardio as it is able to increase both aerobic and anaerobic capacities of the body. Tabata is highly flexible and can be employed in various exercises whether using free weights or bodyweight only. The best Tabata routines will involve warm up and cool down periods with the multi-joint exercises done for 20 seconds followed by 10 seconds of rest repeated for 8 sets within 4 minutes. With the Tabata and HIT programs, having no time to exercise is no longer an excuse.