According to Anderson et al. (2017), world class football players daily energy expenditure can range from 3047 to 4400 kcal per day; additionally, after playing a match of ninety minutes a football player can burn as many as 1500 to 2000 calories. Physiologically speaking, phosphocreatine (PCr) which is used for explosive movements and muscular glycogen (glucose/carbohydrate) that fuels anaerobic activity and large maximal muscle contraction are the two major energy sources used by football players (Miny, Burrowes, & Jidovtseff, 2017). According to Rodrigues dos Santos, J. A. (2017) at approximately 60 to 65% VO2 max, both fat and carbohydrate are used as source of energy roughly equal. Above 60 to 65% exercise intensity carbohydrate becomes the main fuel and its maximum availability is essential; consuming appropriate nutrition is vital for optimal performance.

Another important aspect of nutrition for performance is fluids lost and intake. For example, the average weight of the English Premier League (EPL) player is 80.5 ± 8.7 kg (Anderson et al., 2017). The expected sweat rate of a player competing in the EPL between August through May with temperatures averaging 12 to 15 Celsius/53 to 59 Fahrenheit is 1.6 L/h, and 1.8 L/h in the summer. The allowable weight loss before dehydration is less than 2% of athlete’s body weight lost to sweat. With that, an athlete of 80kg-2% of body weight (= 78.4 kg) may lose up to 1.6 kg. It’s important to note, the human body is composed approximately of 60% of water and individuals with more lean muscle mass have a higher percentage of water in the body. Consuming fluids is extremely important for functions within the body. For example, water helps to transport nutrients and hormones, removal of wasted material, is involved in the energy production, and water is extremely important in the regulation of body’s temperature (Manore, Meyer, & Thompson, 2009). Noting that dehydration (water reduction of 2% of body mass) can increase cardiovascular stress, decreases the body’s ability to perform aerobically, and limiting the body to cool itself.

Regarding vitamins and minerals, Rodrigues dos Santos, J. A. (2017) found that football players consuming a balanced diet usually do not show a deficit in minerals and vitamins. In addition, Manore, Meyer, and Thompson (2009) showed that nutritional sources from: meat, fish, beans, fruits, vegetables, seeds, and milk provide sufficient vitamins and minerals for optimal performance. Therefore, there is no need for supplementation intake to address deficiency in vitamins or minerals. Interestingly, Rodrigues dos Santos, J. A. (2017) showed in accordance with other studies that when vitamin C and E are consumed as a supplement without appropriate recommendation/prescription, it presents a deleterious effect that “hampers/obstructs cellular adaptation to endurance training decreasing the markers of mitochondrial biogenesis” (it’s a major adaption of skeletal muscle to exercise training).

Supplementation can also play important role in performance; however, it requires understanding. For example, Chaves Oliveira et al. (2017) proposed that consuming caffeine as a supplement may help football players to enhance performance. For instance, caffeine helps to decrease the rate of perceived exertion, enhances attention, increases speed when performing a mental task, and decreases fatigue. This process of delaying fatigue and improving performance is attributed generally to its mechanism of action in the central nervous system. In addition, caffeine works as antagonist for adenosine A1 receptors localized in almost all brain regions including hippocampus cerebral cortex, cerebellar cortex, and thalamus. As a result, caffeine may affect performance facilitated by the process of elevating the release of dopamine levels in the prefrontal cortex (Boere et al., 2016).

Creatine is another positive supplement shown to improve performance. Creatine enhances PCr storage in the muscles, increases the rate of PCr resynthesizes, and helps with re-formation of adenosine triphosphate (ATP), which is used during high intensity physical demands. As a result, muscular contraction can be executed with greater power and strength. In addition, football players using creatine may require less time for recovery between bouts of high-intensity activity, such as short sprints, which could improve performance (Miny, Burrowes, & Jidovtseff, 2017). According to The Fédération Internationale de Football Association (FIFA), creatine and caffeine for optimal football performance may be ingested as follows, creatine 10 to 20 grams per day for 4 to 5 days and then 2 to 3 grams per day for maintenance. Coffee intake should be based on 1 to 3 mg/kg.

Practical Application

Football is one of the most enjoyed sports in the world. The game’s physicality has tremendously increased compared to 20 years ago (Chaves Oliveira et al., 2017). For instance, techniques and tactics such as passing, dribbling, crossing, and running without the ball are executed several times more in the current game when compared to 20 years ago. A nutritional strategy to improve football player performance may be proposed as follows: carbohydrate: 5 to 10 g/kg/day; protein: 1.2 to 2.0 g/kg/day; fat: 20 to 25% of total energy intake. In addition, a professional athlete should drink between 450 to 675 mL of fluid for every 0,5 kg of body weight lost during training (Rodrigues dos Santos J. A. 2017).

Research concluded that football player’s balanced diet (Rodrigues dos Santos, J. A. 2017) composed of meat, fish, beans, fruits, vegetables, seeds, and milk provide sufficient vitamins and minerals for optimal performance (Manore, Meyer, & Thompson, 2009). Furthermore, creatine supplementation showed to positively affect athlete’s performance by improving mechanisms generators for muscular power and strength output; creatine may also improve muscular hypertrophy and muscular repair (Miny, Burrowes, & Jidovtseff, 2017). Regarding caffeine, research showed that it can directly impact an athlete’s performance. For example, improvements in total running distance, sprinting performance, jumping actions during football training and matches (Chaves Oliveira et al., 2017).

In conclusion, a nutritional plan including pre-training, in-training, and post-training periodized accordingly, can help football athletes to improve aspects such as accelerating recovery, achieving and maintaining an optimal body weight and physical condition, and decreasing the risk of injury and illness. Hence, understanding norms, effects, and appropriate dosage are critical for optimal performance and safety. For instance, creatine intake of 10 to 20 grams per day for 4 to 5 days and then 2 to 3 grams per day for maintenance. Coffee intake should be based on 1 to 3 mg/kg. Football is an extremely demanding sport regarding to energy expenditure. Professionals in the field must have specific knowledge to help football athletes maximize performance and overall health based on adequate nutrition.

Reference

Anderson, L., Orme, P., Naughton, R. J., Close, G. L., Milsom, J., Rydings, D., & Morton, J. P. (2017). Energy Intake and Expenditure of Professional Soccer Players of the English Premier League: Evidence of Carbohydrate Periodization. International Journal of Sport Nutrition & Exercise Metabolism, 27(3), 128-138.

Boere, J. J., Fellinger, L., Huizinga, D. J., Wong, S. F., & Bijleveld, E. (2016). Performance pressure and caffeine both affect cognitive performance, but likely through independent mechanisms. Brain and Cognition, 10226-32. doi:10.1016/j.bandc.2015.11.006

Chaves Oliveira, C., Ferreira, D., Caetano, C., Granja, D., Pinto, R., Mendes, B., & Sousa, M. (2017). Nutrition and Supplementation in Soccer. Sports (2075-4663), 5(2), 1. doi:10.3390/sports5020028

FIFA. (2006). Supplements and Sports Food. Retrieved from: https://resources.fifa.com/image/upload/supplements- 513854.pdf?cloudid=qsz5oyrdmbrd5jvacgiz

Manore, M., Meyer, N.L., & Thompson, J. (2009). Sport nutrition for health and perfor mance (2nd Ed.) Champaign, IL: Human Kinetics.

Miny, K., Burrowes, J., & Jidovtseff, B. (2017). Interest of creatine supplementation in soccer. Science & Sports, 32(2), 61-72. doi:10.1016/j.scispo.2016.11.00

Rodrigues dos Santos, J. A. (2017). Nutrition for Soccer. / Nutrição para o futebol. Revista Portuguesa De Ciências Do Desporto, (1), 75-107.