“Coach, let’s do HIIT today!” “Hmm, not a good idea”

How many times have you heard this? Let’s add HIIT to make us feel better? It’s not uncommon. HIIT is popular, but in fact, its popularity resides more amongst the scientists. Coaches are more conservative, and fear the implementation of HIIT, at least as it is described in scientific papers. Indeed, the very first studies of the revised HIIT model from Canada described a HIIT protocol with repeated 30 sec all-out bouts on the bike while pedalling against an external load of 0.075 kp per kg body weight (6). As the area evolved, more real-world protocols were developed (8), such as a sprint interval training session involving 8-12 x 30 sec bouts at 90-95% of maximal running speed, interspersed by 3 min rest periods. Véronique Billat proposed another program that consists of repeated 15 sec high-intensity bouts with 15 sec of low-intensity or rest in between (1, 2). So, I believe we are now in a position to say that we have some realistic proposals to put on the table for consideration by coaches. Martin and Paul have further advanced our knowledge, proposing easy-to-use protocols (4, 5) that are extended further in the book and course across 20 sport application chapters contributed by practitioners at the coalface of elite sport. We now have the program. Our next step is to read between the lines before we talk to the coach. With that being said, I’d like to put forth some hidden issues that are likely to arise in the team sport context when you defend your plan to the coach. Injuries “Aren’t we at higher risk of injury doing HIIT compared to conventional football training”? The answer is both yes and no. We are at higher risk when we do HIIT if we haven’t respected the basic rule of progressive overload, which is fundamental to safe exercise training periodization. We recently showed this in a study, where conventional football training was complemented with adjacent HIIT sessions (11). Across 4 weeks, endurance performance was improved, and no injuries occurred. It’s important to appreciate that injuries can be the consequence of lower than optimal fitness due to inadequate training. Indeed, the model proposed by Tim Gabbett suggests that low fitness itself may be a risk factor for non-contact injuries. In contrast, high levels of fitness may protect against injuries (7). Thus, a focus towards ensuring high aerobic fitness in our players should actually protect them from non-contact injury occurrence. Of course, this only occurs when we build the training program in a progressive manner. Our limited resource – time   It’s important to appreciate that coaches have a program to run. They are concerned with training as a team, not as an individual player. They have to be. That’s why today, most of our training time in football use small-sided games (SSGs), which are useful for building and maintaining match-specific technical and tactical elements (9). Additionally, we know that playing SSGs will assist to develop some of the match- specific physical fitness elements. With full respect to the use of this approach, SSGs have limitations too. For example, SSGs might not be specific enough to a player’s individual needs. Often, SSGs won’t provide enough stimulus to build key football-specific elements, like the ability to perform long intensive efforts. The solution? Supplement your SSGs with specific short interval HIIT. For example, you might use 2-3 sets of repeated 15 sec or 30 sec bouts at 90-95% of maximal speed (8, 9). Another option would be to perform repeated bouts of either 30 sec at 110% of the velocity attained during the 30-15 intermittent field test (V_IFT) (3) or 15 sec repeats at 120% of V_IFT (11). The programs don’t take much time and bring great benefit. After convincing yourself, the next step is to convince the coach. That’s either the easy or the hard part of the day, depending on your relationship. I’m talking about the human connection, because that’s the foundation of any professional relationship. Building trust is key. I can’t emphasize the importance of this enough or give you advice on how to go about this. It’s personal. The ability to build trust in human relationships incorporates everything; who you are, where you come from, what your life expectations are, your values and beliefs – seeing the other person for who they are and they, in turn, seeing you. Are you there on the team to satisfy your personal inner needs and professional ambitions, or are you there to contribute to making a common dream a reality? Do you believe science is everything or do you feel you are part of the team, a member of the family, where using science can help to make it better? Of course, there are theories from the social sciences, like the diffusion of innovation theory, which can help you further build your skills in effective communication of science (10). However, I’m not sure if it is so much knowing the science sometimes over trusting your own intuition. After so many years in the field, I tend to believe that sometimes it’s a combination of both. Know the science, gain the experience, before putting trust in your intuition. It usually leads you in the right direction. Going back to where we started. Instead of “Coach, let’s do HIIT today”! Let’s try a new approach: “Coach, what do you think about doing HIIT today? Do you like the plan? Any ideas on how we could make it better?”   George Nassis, PhD, is a sport scientist/exercise physiologist, former head of Performance Lab at Panathinaikos FC and former head of Excellence in Football, Aspetar. Follow him on Twitter (@gnassis) and on ResearchGate. References

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2. Billat LV. Interval training for performance: a scientific and empirical practice. Special recommendations for middle- and long-distance running. Part II: anaerobic interval training. Sports Med 31: 75-90, 2001.
3. Buchheit M. The 30-15 Intermittent Fitness Test : 10 year review. Myorobie Journal 1: 1-9, 2010.
4. Buchheit M and Laursen PB. High-intensity interval training, solutions to the programming puzzle: Part I: cardiopulmonary emphasis. Sports Med 43: 313-338, 2013.
5. Buchheit M and Laursen PB. High-intensity interval training, solutions to the programming puzzle. Part II: anaerobic energy, neuromuscular load and practical applications. Sports Med 43: 927-954, 2013.
6. Burgomaster KA, Hughes SC, Heigenhauser GJ, Bradwell SN, and Gibala MJ. Six sessions of sprint interval training increases muscle oxidative potential and cycle endurance capacity in humans. Journal of Applied Physiology 98: 1985-1990, 2005.
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8. Iaia FM and Bangsbo J. Speed endurance training is a powerful stimulus for physiological adaptations and performance improvements of athletes. Scand J Med Sci Sports 20 Suppl 2: 11-23, 2010.
9. Lacome M, Simpson BM, Cholley Y, Lambert P, and Buchheit M. Small-Sided Games in Elite Soccer: Does One Size Fit All? Int J Sports Physiol Perform 13: 568-576, 2018.
10. Nassis GP. Leadership in science and medicine: can you see the gap? Science and Medicine in Football 1: 195-196, 2017.
11. Paul DJ, Marques JB, and Nassis GP. The effect of a concentrated period of soccer specific fitness training with small-sided games on physical fitness in youth players. J Sports Med Phys Fitness, 2018.