Acronym of High Intensity Interval Training, the H.I.I.T. it is a training method that is part of Interval Training, workouts that alternate short periods with high intensity of work with periods of active recovery in which exercises are performed bland.
The main characteristic of H.I.I.T. is its duration: a training session can last from 4 to 20 minutes and consists of a warm-up period followed by 6-10 repetitions of high intensity exercises, interspersed with moments of recovery (the original protocol provided for a relationship of 2: 1 between intense work and recovery). Finally, the cool down, which normally must be as long as heating.
The number of repetitions, their duration and recovery time are all variables that are modified, as well as by the various protocols used, also depending on the degree of training chosen.
By undermining all the certainties on which the training practices and common beliefs are based, the mistrust that still surrounds this methodology seems to be natural, which many consider only an advertising and deceptive tool to guarantee results in a very short time. On the other hand, there are numerous studies that demonstrate the real effectiveness of H.I.I.T.,
Among the first studies stands out that of Dr. Izumi Tabata of the National Institute of Fitness and Sport in Tokyo that at the end of the 90s proposed a protocol of 20 seconds of very intense training alternating with 10 seconds of recovery repeated for 8 times for a total of just 4 minutes. Then there is a work of 2006 conducted by Prof. Matin Gibala of the Department of Kinesiology of McMaster University in Canada, which showed that 2.5 hours of H.I.I.T. they equate to 10.5 hours of resistance work by evaluating the production of biochemical muscle changes as well as the results obtained in terms of improving aerobic performance.
Other studies show that the H.I.I.T. is able to increase the resting metabolic rate for the next 24 hours, thanks to what is defined by the concept of EPOC (Excess Post Exercise Oxygen Consumption), or the result of a series of biochemical processes (including the resynthesis of ATP , the resynthesis of creatine phosphate, the resynthesis of glucose and glycogen starting from lactic acid, the oxidation of lactic acid in pyruvic acid, the thermoregulation processes, etc.), whose functionality must be guaranteed by the right contribution of oxygen at the end of the performance (thus increasing post-workout oxygen consumption).
The H.I.I.T. therefore increases the time necessary for the body to recover its physiological balance, therefore, despite the relative brevity of the session, the caloric consumption derived from this effect is higher than that of a classical resistance session.
The H.I.I.T. then causes some metabolic adaptations – including improved insulin action – that allow the use of fats as fuel to produce the energy needed to cope with the effort, thus associating a proven slimming action with improved performance.
Moreover, thanks to its methodology that combines moments of anaerobic activity (in intensity peaks) with aerobic recoveries, it limits the muscular loss often associated with classical resistance work.
What makes H.I.I.T. truly “special” compared to the other Interval Training, in addition to the temporal factor, is that the high intensity interval must be considered as the maximum effort that can be performed (this is also called Interval Training Sprint), and you do not simply work at a heart rate a slightly higher than the previous ones. From this it follows that the maximum effort can hardly last more than 60 seconds and that the exercises to be performed to reach these frequencies must involve the largest possible muscle groups.
The effort that well represents the one required in the intensity peaks is that of the centimeter or the cyclist’s sprint; it is therefore impossible, if not changing the meaning of the training itself, an interval greater than 30-60 seconds. Just as it is unthinkable to reach such intensity peaks with free-body exercises such as biceps alternating with dumbbells, adductors and buttocks, push ups, squats, etc., which can however be used in times of active recovery.
Therefore, it is not possible to schedule a daily appointment with the H.I.I.T., but it is necessary to estimate a recovery day because the body needs at least 24 hours to regain its balance and be able to express itself afterwards to the maximum of its possibilities.
For the irrepressible impact it is important, especially if you are fasting sporting practice, gradually approaching the H.I.I.T. An 8-week introductory program is recommended.
Once the natural prejudices have been won, it will be appreciated by the H.I.I.T. also its extreme simplicity: no special tools are needed for its development and can be practiced anywhere.
Jump, run, swim, ride, everything is fine as long as you can perform the exercise as quickly as possible (without, of course, neglecting the correctness of the athletic gesture).
For the relevance of the effort, before starting the H.I.I.T. it is good to undergo a thorough physical medical examination with an echocardiogram under stress in order to exclude particular cardiac pathologies.