[Matty Golden is in his third year as a sports strength and conditioning student in Setanta College, Ireland and is due to graduate in May 2018. He is currently an Athletic Development Intern at the Athletic Lab.]

High intensity interval training is a method used to supplement maximal efforts in training. This is a method of training that involves repeated bouts of high intensity efforts that range from 5 seconds to 8 minutes followed by recovery periods of varying length of time. It is quick, intense bursts of exercise followed by rest periods. HIIT trains the body at high heart rates which aids the burning of fat in shorter periods of time. As quoted in a study done by Martin, J Gbala, High Intensity Interval Training is a little pain for a lot of gain. Billat (2001) points out that as early as 1912 that Olympic long distance runner, Hannes Kolehmainen, was employing interval training in his workouts. Often times high intensity interval training is emphasised as less is more. Meaning a fast paced 30 minute workout is more beneficial to fat loss then something of a slower pace with a longer duration. In a paper done by Micah Zuhl and Len Kravitz they explain how HIIT can not only provide performance benefits but it can also improve the health of recreational exercisers. They go on to state that it is also very suitable for endurance training or continuous aerobic exercise. HIIT is a method of training I have used in Ireland both with sport teams and individuals.

With highly trained athletes and individuals, increasing volume of the training does not appear to further enhance their endurance performance or peak their oxygen uptake. I am referring to highly trained athletes as individuals with years of experience of training who are professional athletes or elite amateurs. For individuals of a professional or elite amateur standard, it seems that training benefits can only be achieved through high intensity interval training. In a study published by Helgerud et al (1998) with professional soccer players, he concluded that HIIT had significant improvements that relate to match or game like demands, including VO2 max. VO2 max is your peak oxygen uptake or maximal aerobic capacity. For field sports teams that require high endurance examples of this training would include MAS training (Maximal aerobic speed) and some tempo runs. Maximal aerobic speed is simply the lowest running speed at which maximum oxygen uptake occurs (Berthoin, S. 1992). MAS was developed for the purpose of increasing the specificity of training and to enable coaches to monitor training loads more accurately. An example of a MAS training session for team athletes in pre season can be seen below. It is a technique of endurance training we see a lot of in pre season for teams or for rehab of an individual. High intensity interval training can also be seen in endurance boot camp classes with examples of lots of time on the exercise with little rest (e.g 40 seconds on x 20 seconds rest). Warm ups for HIIT have similarities regardless of your base fitness level. A common objective here is raising the athlete’s heart rate to the significant level for the upcoming activity using dynamic movements. This style of training provides similar fitness benefits as continuous endurance workouts but completed in shorter periods of time.

Example of MAS training:

  1. Warm up = 10-12 minutes
  2. 20 second sprints @ high intensity running
  3. Rest Interval will be short. E.g a 2:1 work ratio
  4. A block of reps will consist of 10-14 reps.
  5. A rest period is designed to bring heart rate levels back down to the normal rate. That generally takes 4-6 minutes.
  6. Cool down of 8-10 minutes light work with movements to allow gradual lowering of heart rate levels.

Many benefits of HIIT include:

  • It can increase your metabolism.
  • It can be a convenient style of training as the duration is not as long.
  • You can train without any or very little equipment.
  • The above also meaning you can do it anywhere that suits you.
  • It burns more calories.
  • You lose weight, not muscle which is crucial.
  • It can be very challenging.

Safety Concerns of HIIT & Common Mistakes

Training HIIT to the general public has safety concerns. As a coach you will have to determine a level of fitness suitable for the session known as their base fitness level. Family history, cigarette smoking, hypertension, diabetes, abnormal cholesterol levels and obesity increase the risks during high intensity interval training. Often the case a medical clearance from a physician is needed prior to training. Regardless of age, gender and fitness level, one of the keys to safety participation of HIIT training is for all people to modify the intensity of the work interval to a suitable and preferred challenging level.

Mistakes with HIIT include:

  • Unable to properly prepare the body for the high intensity training may cause injury. The warm up is crucial.
  • Isolating muscles. This means focusing on just the one muscle, e.g biceps. The mistake in this is that training one muscle doesn’t stimulate enough muscle fibers to actually build muscle.
  • Working with machines, this limits your ability to fully activate all of your muscle fibers, it is also less fat burning.
  • Doing long bouts of cardio. Less is more.
  • Sit ups to get abs.
  • Repeating the same workouts, your body will get familiarized with the load and adapt to the training.
  • Don’t rely upon that this style of training will give you muscle growth.
  • Rest days are crucial as this style of training is very fatiguing.

High intensity interval training can be used for both anaerobic and aerobic training (cardio training). These types of training sessions are short in duration but high in levels of fatigue, therefore you would not complete this style of training every day. This is because the workout is so demanding because of the exercises involving short intervals of maximum intensities with the anaerobic system pushed to its limits by reaching a lactate threshold. HIIT can be done on a treadmill with steady increases. HIRT is another option in regards to interval training. HIRT is very similar to HIIT only it is high intensity resistance training. This type of training is the most effective way to increase your metabolic rate and is often which is often used for fat loss. Your metabolic rate is the amount of energy (calories) that your body needs to function. HIRT also increases your exercise post oxygen consumption (EPOC) whilst also burning calories because the body is using the fat as fuel. EPOC has many factors on the body after exercise. EPOC aids the replenishment of energy resources, it is also used to re-oxygenate the blood and restoration of circulatory hormones, it helps decrease body temperature and return the body to normal ventilation and heart rate.

From researching this topic and looking into it a little closer I have been impressed with the benefits that High Intensity Interval training can achieve when taught and coached correctly. This type of training will be very helpful to teams in pre season. I would also use this style of training to a certain extent with players returning from injuries. Individuals of a moderate fitness level would see great results in fat loss and higher endurance rates through training at high intensities. Recoveries and rest are important after training as body parts will be fatigued.

References:

Hawley JA, Myburgh KH, Noakes TD, et al training techniques to improve fatigue resistance and enhance endurance performance (J Sports sci 97)

Foster, C. V.Farland, Courtney, Guidotti, F. Harbin, M. Roberts, B. Schuette, J. Turri, A. T.Doberstein, S. P.Porasci, J. The effects of high intensity interval training vs steady state training on aerobic and anaerobic capacity

HIIT vs Continous endurance training: Battle of the aerobic titans

Berthoin S, Gerbeaux, M, Geurruin F, Lensel – Corbeil G & Vandendorpe F. Estimation of maximal aerobic speed. Science & Sport 1992.

Hoff J, Wisloff U, Engen LC, Kemi OJ, and Helgerud J. Soccer specific aerobic endurance training, Br J sports med 2002

Bahr, R & Sejersted, O.M. 1991. Effect of intensity of exercise on excess post exercise oxygen consumption.