Why should you specialise in sport and exercise nutrition? – what you already know as a nutrition practitioner and what you still need to learn…

The field of sport and exercise nutrition is rapidly diversifying – it is not only the domain of high performance sport, or ‘performance nutrition’ any more. Active recreational pursuit is now at an all-time high, and these ‘life athletes’ need our help as a health-focussed nutrition practitioner.

There is a common perception amongst nutrition practitioners that working within the field of sports nutrition is purely the domain of high-performance sport nutritionists, trained to quantitatively analyse and support the nutrition needs of individuals who are pushing the boundaries of human performance. While this notion is partially true at the upper end of professional sport, we need to be cognisant that not many athletes of this calibre actually exist – only a select few individuals are fortunate enough to reach such a high level of physical prowess that they actually get paid for doing what they love.

Athletes need our help

If we add the word ‘exercise’ into our description – sport and exercise nutrition – it greatly softens the description of this field of work and massively widens the catchment of active people who could benefit from our support. Bill Bowerman, the co-founder of Nike has famously been quoted as saying “If you have a body, you are an athlete”, although we could perhaps extend that a little with a statement like:

“an athlete is anybody who moves regularly with purpose”.

The purpose, or reason for exercising, is the key question here – in reality, most individuals who take part in sport do so for reasons of health and fitness, personal challenges, social interaction and recreational enjoyment. Whereas 10 or 20 years ago, when the golf courses were full up, now in the 2020s many of these same people are taking on personal challenges, such as CrossFit and Hyrox, military-style training, Park Runs, triathlon events, marathons, wild swimming, cycling events, multi-day mountain biking races, long distance trail running, and even extreme mountain treks. Participation in these events has risen consistently over this time period.

None of these participants, except perhaps for the top one per cent, would be described as elite athletes. And most of them undertake their exercise training while working full time, fulfilling parental responsibilities, being socially active, and generally living the lives of very busy humans. Many skimp on sleep to fit in training sessions, don’t eat well except for dinner time, and exist for most of the time in a sympathetic/flight-or-flight nervous state. Managing life loads and nutritionally supporting busy folks is something that nutrition practitioners are good at, and these ‘athletes’ need our help…

Elite athletes are human beings, just like us

Professional sports people are mostly under the care of the sports nutrition practitioners, (dietitians and nutritionists) who are employed by their team or professional body. However, when such an athlete isn’t getting his or her needs met, or their sport does not receive direct nutrition support, they may reach out for help. But rather than placing an elite sportsperson on a pedestal of invincibility, and becoming overwhelmed by the potential of working with them, it is important to remember that they are also human beings, with the same challenges that all other humans face.

In fact, the harder an athlete trains, the higher the physiological pressure placed upon their body. Elite sport is littered with examples of health imbalances, such as gastrointestinal distress, autoimmunity, post-viral fatigue, diabetes, and of course, common illnesses and injuries. A famous case in point is legendary British rower, Sir Steve Redgrave, who succumbed to both type II diabetes and ulcerative colitis towards the end of his career, that spanned five Olympics (Maffetone and Laursen, 2015). In fact, it’s incredibly rare to find a hard striving sportsperson without a collection of signs and symptoms indicative of compromised health.

If we layer in a problem that has seen rising awareness over the past decade, that of Relative Energy Deficiency in Sport (REDs), we have another role to play when supporting an active individual. At both an elite and recreational level athletes may inadvertently under-nourish themselves while trying to improve their power-to-weight ratio or due to factors such as body dysmorphia and disordered eating patterns. However, because elite athletes tend to have more of a support system around them, it may be the recreational athletes who are more at risk of developing REDs because of their overall life loads, meaning that they will need the support of nutrition practitioners. REDs is a complex scenario though, and often requires a combination of nutrition and psychology support to adequately address. It has been associated with a collection of symptoms, including compromised functioning of: gastrointestinal, reproductive, bone, cardiovascular, skeletal muscle and immune health, plus energy metabolism.

The prevailing thought by nutrition practitioners is that athletes are simply not eating enough for the energetic requirements of their sport (Mountjoy et al., 2023), meaning that these systems do not perform optimally under exercise load. Thus, low energy availability is recognised as the underlying cause of REDs. However, a recent paper has questioned the aetiology of REDs in athletes. Jeukendrup et al. (2024) suggested that many of these REDs signs and symptoms could be derived from other factors, such as training load (overtraining?), illness, and micronutrient deficiencies – all contributing towards to an athlete’s allostatic load. This is perhaps the first time the allostatic load concept has been acknowledged in the sports nutrition literature, suggesting that principles of functional and integrative nutrition are gradually seeping into mainstream academic awareness within sports nutrition.

What we don’t know as nutrition practitioners

Having affirmed that nutrition practitioners are extremely well placed to work with athletes, whether recreational or elite, it’s also vitally important to acknowledge what we don’t know. For example, when learning about base physiology and biochemistry within the study of nutrition, it tends to be relative to a lay individual at rest. During exercise the fundamentals of physiology and biochemistry are the same, but the context of function is different, meaning that nutritional demands change. Metabolic activity increases markedly during exercise. The Compendium of Physical Activities (Herrmann et al., 2024) uses METs (metabolic equivalents) to rate many activity types based on resting metabolic rate (RMR), roughly the energy cost of sitting quietly. In contrast, taking cycling as an example, leisurely cycling at around 12 miles per hour may require about 8 METs (8 x RMR) and competitive mountain biking may require 16 METs. These figures will of course vary based on the fitness of the individuals and their exact energy outputs.

Therefore, metabolic and nutritional needs increase greatly during exercise, and athletes must be supported as such. Looking at this through a simple lens of exercise training, though, many sports nutrition professionals can tend to over-emphasise the importance of carbohydrates for the general needs of an athlete, even during a low load of exercise (e.g. Thomas et al., 2016). Conversely, avid researchers of fat metabolism would have us believe that all we need as an energy substrate is fat (e.g. Volek et al., 2016). The reality is much more complex and nuanced than these examples, especially when we take genetic considerations of substrate utilisation into consideration, along with the specific exercise scenario (e.g. high versus low intensity; short versus long duration).

It has been accepted for a long time that fat is our dominant substrate (energy source) at rest and during low intensity exercise. But as exercise intensity increases, carbohydrate metabolism gradually increases until it becomes the dominant energy source – this has become known as the “crossover concept” (Brooks and Mercier, 1994). Nutritional recommendations for athletes, especially before and during the activity, therefore need to be paired with the exercise intensity and duration plus relative fitness of the individual and their genetic metabolic preferences (i.e. how well they burn fats and carbs).

This leads us onto ‘nutrient timing’, a concept that was coined in 2004. Originally, there was a strong emphasis on eating and drinking carbohydrate and protein-rich snacks and fluids around exercise sessions, but as research has started to show the impact of prior meals on substrate availability during exercise and the recovery period, sport- and exercise-specific nutrition feedings have been called into question. Context is again vital, however. If a recreational exerciser completes a gentle session at the gym three times per week, their regular (healthy) eating patterns are most likely sufficient, whereas if we’re dealing with an individual who trains intensively, for a long duration, daily, and/or experiences a high life load, nutrient timing can be an effective strategy (Arent et al., 2020).

Often when nutritional therapists start to study sports nutrition, they are shocked by the sugary sports drink recommendations, but it is important to note that during training scenarios that require this kind of carbohydrate support, DIY sports drinks (LINK) can be made out of healthy base ingredients such as fruit juices and naturally sweetened iced teas. Again, creation of recipes is generally another good skillset of nutritional therapists!

Upskilling to a specialty in integrative sport and exercise nutrition

As explained by the earlier definition of an athlete, “an athlete is anybody who moves regularly with purpose”, many nutrition practitioners are now working in a sport and exercise context without necessarily choosing to do so. Individuals may seek assistance for health concerns, such as gastrointestinal, endocrine or body composition issues, but at the same time they are exercising regularly. The base skills of our profession means that we are well placed to support the health needs of that individual, and that might be enough… However, if the individual is demanding a lot of their body, either by training and completing at a high level, or by managing a high life load to accommodate their exercise demands, and especially if the health imbalances may relate back to their training loads, some degree of specialisation in sport and exercise nutrition is essential. The nutrition practitioner could choose to refer on to such a specialist, or they may wish to support the person themselves – after all, there is a rising need for support of recreational exercisers.

If you choose to up-skill your practice within sport and exercise nutrition, you’d have the opportunity to increase your specific expertise in many exercising contexts, thereby being able to help active clients with more confidence. Having studied various applications of nutrition (general nutrition combined with sport and exercise nutrition) you’d then become more adaptable as a practitioner, allowing you to navigate shifts in your own practice, and adapt to the plethora of trends in the field. There would also be an opportunity for you to expand your network as you engaged with your new practitioner peers, athletes, coaches, exercise professionals, and mentors.

Choosing to study further, there are a diversity of options. Most quality sports nutrition education options are degree (BSc and MSc) oriented, some of which will allow you to build up a portfolio of practice for the Sport and Exercise Nutrition Register (SENR). SENR is run by the British Dietetic Association and many sports clubs now require this registration if you apply for a high-performance sports nutritionist role. However, if you’d prefer not to undertake another degree, and require more flexibility of studying around your existing nutrition practice, three online Level 7 (postgraduate equivalent) diplomas in sports nutrition exist.

• The International Olympic Committee (IOC) Diploma in Sports Nutrition guides you through the fundamentals of sports nutrition (energy balance, macro and micronutrients, hydration, training and competition preparation) in year one, and prepares you for a number of sporting scenarios and environmental conditions in year two.
• The Institute of Performance Nutrition (IOPN) PGDip in Sports Nutrition progresses you through four modules; Human nutrition and exercise metabolism, Macronutrient digestion, absorption and metabolism, Hydration, micronutrients and supplements, and Advanced sport and exercise nutrition.
• The Centre for Integrative Sports Nutrition (CISN) Diploma in Integrative Sport and Exercise Nutrition starts with an integrative body-systems approach within the context of sport and exercise nutrition, followed by an applied performance nutrition module and four specialty modules of your choosing. You’d then undertake an applied mentoring and case studies module plus a qualitative research project. CISN also hosts a smaller practitioner-focused certificate course and several 20-hour CPD units.

So, should you choose to up-skill your nutrition qualification and specialise in the field of sport and exercise nutrition, the depth of training very much depends on your appetite for learning. Some nutrition practitioners choose to jump straight into a degree programme or postgraduate qualification, which can take a number of years to complete, whereas others will opt to pick practitioner-focussed training, CPD study units, and webinars, podcasts and articles that align with their interests.

Whatever choice you make, sport and exercise nutrition is a rapidly developing discipline: according to Professor Graeme Close from Liverpool John Moore University, roughly 107 research papers were published in 2005 using the search term “sport nutrition”, whereas that number exceeded 3,500 papers in 2024! Adding the word ‘exercise’ to the description widens the research and practice applications considerably, meaning that more and more nutrition practitioners will be required to support these active individuals. And, noting that regular exercise training can markedly increase physiological pressures, especially when combined with a high life load, the adaptive thinking of a well-versed nutrition practitioner will come in very handy!