A brief history of sports nutrition – Professor Justin Roberts

This is an extended version of the history of sports nutrition section in the Textbook of Integrative Sport and Exercise Nutrition.

Although the academic study of sport and exercise nutrition is relatively recent, the idea of using nutrition to enhance performance dates back to the earliest forms of physical activity and competition. One of the first documented examples of training principles comes from Ancient Greece. Milo of Croton, a 6th-century BC wrestler, reportedly built exceptional strength by lifting a young calf above his head each day. As the calf grew, so did Milo’s strength, eventually earning him six consecutive Olympic wrestling titles (1). This legend helped inspire the concept of progressive resistance training. Interestingly, Milo was also said to consume large quantities of meat, bread, and wine, although these accounts may have been exaggerated. Other historical records mention long-distance runners who typically ate wheat, barley, figs, and cheese, but saw improved performance after adding meat to their diets, a practice even noted by the Greek philosopher Pythagoras of Samos (580–500 BC – 1).

Until the modern era, reports pertinent to the history of sports nutrition or performance are somewhat sparse. However, it is noteworthy that whilst protein-rich foods were still viewed as important ‘fuel’, food availability also appeared to be relevant to performance in medieval games. The practice of ‘intermittent fasting’ (possibly explaining, in part, the longevity of knights), appeared to be followed by feasting (which may in fact be one of the first indications of carb-loading practices prior to tournaments and ‘sport for entertainment’). Medieval knights reportedly consumed cereals, including bread and porridge (with varying consistency); as well as side dishes including roasted meats (typically only a few times per week), fish, eggs, fruits and vegetables, and largely hydration through water, buttermilk and low-alcohol ale. It is also believed that such knights ate in pairs to enact a type of ‘portion control’, with any excess foods being given to the poor.

History of sports nutrition – macronutrient considerations

Fast-track to the late nineteenth century and protein was still widely regarded as the primary fuel for exercise performance (2). This belief persisted into the early twentieth century, with reports of Olympian diets indicating exceptionally high protein intakes, up to 320 grams per day. For a typical 70 kg male athlete, this equated to over 4.5 g∙kg⁻¹∙d⁻¹, largely sourced from steak, poultry, and concentrated ‘meat-juice’ extracts. As nutritional assessments became more detailed, the role of carbohydrates in supporting muscular work also gained recognition around this time. As demonstrated in a large-scale study of the diet of ~4700 athletes from 42 nations (3), athletes taking part in the Berlin Summer Olympics were reported to consume an average of 850 g∙d⁻¹ of carbohydrates (approximately 12 g∙kg⁻¹∙d⁻¹), a level comparable to that of a modern-day Tour de France cyclist. Notably, fat intake was also substantial, averaging around 270 g∙d⁻¹ (or 3.9 g∙kg⁻¹∙d⁻¹ for a 70 kg athlete).

In context, even in the 1930s, there was clear awareness among athletes of the need to significantly increase caloric intake to support training and performance. The concept of a mixed macronutrient diet was already evident, with typical distributions around 18% of energy intake (EI) from protein, 48% from carbohydrates, and 34% from fat. However, beyond total energy and macronutrient composition, there was marked cultural variation in dietary practices. Athletes from different countries incorporated diverse foods, including various plant-based items, fruits, natural and added sugars, coffee, and even early dietary supplements such as malt extract and lecithin.

Technological and medical advancements in the early twentieth century, combined with growing political interest in competitive superiority, contributed to some of the first studies examining the role of blood sugar in fatigue and mental performance. These early investigations highlighted the importance of maintaining blood glucose levels during exercise, aligning with the discovery that stored carbohydrate in muscles, known as glycogen, was directly linked to muscular work (4,5,6). This connection suggested that limited glycogen availability could impair sustained physical performance, again linking back to the importance of dietary carbohydrate for endurance sports.

After the 1940s, following the discovery and classification of all amino acids, scientific interest expanded to include dietary protein, particularly its role in promoting muscle growth and size. Alongside the concept of a larger muscular ‘engine’ capable of storing more glycogen, the strategic intake of both carbohydrates and protein was increasingly viewed as a way to enhance athletic performance.

The influence of exercise physiology research

By the 1960s, with direct relevance to the history of sports nutrition, exercise physiology research began exploring the underlying mechanisms of maximal performance, including oxygen uptake, lactate dynamics, and the distinction between aerobic metabolism at lower intensities and anaerobic metabolism at higher intensities (7). Advances in muscle biopsy techniques and fibre typing enabled more precise investigations into the physiological impact of nutrition on performance. Seminal studies identified how food intake and exercise influenced glycogen storage and depletion in muscle fibres (8,9). These findings were further supported by a growing body of research demonstrating that higher pre-exercise muscle glycogen concentrations could enhance race performance and prolong endurance capacity (10-13).

Advancements in our understanding of exercise metabolism via studies of energy demands, muscle biopsies, and cardiorespiratory assessments led to the foundational concept of the metabolic crossover effect, where the body shifts from fat to carbohydrate as the primary fuel source with increasing exercise intensity (14). These studies also demonstrated that metabolic efficiency can be improved through training adaptations.

The carbohydrate era

During the 1980s and 1990s, within the history of sports nutrition, researchers focused heavily on dietary strategies to optimise muscle glycogen stores before endurance events. This work laid the foundation for both traditional and modified carbohydrate loading protocols (8,11). However, more recent research has begun to challenge some of these practices. First, it has been shown that glycogen stores can be maximised within 48 hours through very high carbohydrate intake (15). Second, if carbohydrate availability is maintained through appropriate pre-exercise meals and carbohydrate intake during exercise, the need for extended carbohydrate loading may be less critical than previously believed, particularly in female athletes (16).

Alongside developments in carbohydrate research, prominent scientists such as Professors David Costill and Edward Coyle pioneered investigations into hydration and fluid balance during endurance exercise. Their early studies examined topics such as ‘fluid ingestion during distance running’ (17) and ‘gastric emptying rates of various athletic drinks’ (18,19). These works laid the foundation for understanding the critical role of hydration and electrolyte balance in sports performance and contributed to the development of sports drinks, particularly in relation to preventing hyponatremia (low blood sodium levels).

Throughout the 1980s and 1990s, research into exogenous carbohydrate oxidation also expanded, highlighting how carbohydrates from sports drinks are used during exercise in both trained and untrained individuals (20). Technological advances in maltodextrin production and a deeper understanding of intestinal glucose transport mechanisms (21) led to important breakthroughs in the use of multiple transportable carbohydrates. This approach, which combines different carbohydrate types to enhance absorption and oxidation rates, was supported by further studies (22-24) and has informed the optimal carbohydrate intake guidelines widely recommended today (25). In more recent times, this has morphed towards hydrogel technology and similar nutrients (e.g. isomaltulose) to facilitate ‘slower-releasing’ carbohydrate solutions, with less impact on the gut.

The rising awareness of ketogenesis

Within the history of sports nutrition, there has been considerable interest in the role of ketogenesis in enhancing endurance performance. The development of the metabolic crossover concept, along with the widespread use of respiratory exchange ratio (RER) and stoichiometric equations based on oxygen and carbon dioxide measurements, sparked investigations into fat oxidation and the effects of short-term high-fat diets (26). While the prevailing evidence has supported high-carbohydrate diets as being beneficial for endurance performance, particularly by maintaining muscle glycogen, research in the 1990s began to highlight the potential advantages of high-fat diets in ‘preserving’ glycogen stores and improving endurance capacity (27).

This interest gave rise to the ketogenic diet, originally developed for the medical treatment of epilepsy. Despite ongoing debate regarding its effectiveness and the extent of performance benefits, especially at higher exercise intensities (28), the ketogenic diet remains a focus of scientific and athletic discussion. In parallel, there has been growing attention to thermogenic or ‘fat-enhancing’ nutrients aimed at boosting the metabolic effects of exercise, although results have generally been limited. More recently, novel ketone esters have been investigated for their potential to enhance exercise performance (29), and research in this area continues to evolve.

Sports nutrition and muscular growth

Within the history of sports nutrition, we should also acknowledge the rapid growth of protein-related research, alongside the rising interest in ergogenic compounds such as creatine (30,31) and HMB (hydroxymethylbutyrate – 32). The 1990s saw the emergence of sports nutrition companies driven by the growing popularity of natural bodybuilding, sparking a race to develop the most effective products for active lifestyles and physique transformation. Early studies focused on the mechanistic effects of nutrient combinations that had anabolic (muscle-building) or anti-catabolic (muscle-preserving) properties (33), with university research demonstrating improvements in physiological and strength performance measures.

Interest then shifted to optimising protein intake for muscle growth by examining the maximum effective doses (fractional synthetic rate) and the timing of nutrient consumption (34,35). This work has heavily influenced current recommendations and normative data on protein intake (36,37). Building on this foundation, research into age-related muscle loss (sarcopenia) spurred interest in specific amino acids, such as L-leucine, which play key roles in activating muscle growth pathways like mTOR (38). Additionally, studies highlighted the benefits of targeted nutrient timing, including strategic ingestion at points such as pre-sleep (39) to maximise recovery adaptations.

Beyond creatine, significant research has focused on other ergogenic nutrients, including buffering agents such as sodium bicarbonate (40,41) and beta-alanine (42). Extensive studies on caffeine (43,44) have also shaped the dosage guidelines commonly recommended in sports today.

The evolving power of plants

In 2009, experimental research, which has been very influential within the recent history of sports nutrition, revealed that acute consumption of beetroot juice could reduce the oxygen cost of exercise and improve tolerance to short-term high-intensity efforts by approximately 16% (45-47). This work not only highlighted the physiological benefits of specific compounds found in plant-based foods but also aligned with emerging research on polyphenols and their role in reducing muscle damage and enhancing recovery after exercise (48,49). These findings have helped to reinforce the growing emphasis on plant-based nutrients and the importance of a ‘food-first’ approach to sports nutrition (50).

Efforts to provide athletes with up-to-date scientific guidance led to early consensus statements (51) and more recent International Olympic Committee (IOC) consensus statements (52). Additionally, awareness has increased around conditions such as the ‘Female Athlete Triad’ (53) and the broader concept of Relative Energy Deficiency in Sport (REDs) (54,55). These developments further underscore the importance of personalised and periodised nutrition strategies tailored to individual athlete needs (56).

In recent years, plant-based, vegan (57), Paleolithic-style (58), and even gluten-free diets, have gained popularity, partly due to their adoption by mainstream athletes and reported health and metabolic benefits (59). However, there remains limited scientific evidence supporting the direct impact of these dietary approaches on physical performance. A closer look at some experimental studies suggests that any observed benefits may stem from factors such as reduced caloric intake, lower glycaemic load of consumed foods, and high polyphenol content, each of which could promote favourable adaptations in the gut microbiome.

As the history of sports nutrition advances into the future of sports nutrition, interest is growing in the potential ergogenic effects of phenolic compounds and how food choices influence gut health, microbiota diversity, and the mechanistic pathways that may optimise training adaptations. The future of sports nutrition looks nutritionally bright – we have certainly come a long way!