Protein is an essential macronutrient and a huge topic in sports nutrition so I will do my best to give you the highlight reel here.
FUNCTION: protein is used to build and repair muscle, tissue, skin, nails and hair. Protein also has a role in building hormones and enzymes. For sports nutrition the big topic is building and repairing muscle. Our body needs to be in positive muscle protein turnover (the positive balance of muscle protein synthesis (MPS) over muscle protein breakdown (MPB)) to build muscle. By pairing endurance and/or resistance exercises with protein consumption you can build and repair muscles.
SOURCES: Protein comes from both plant and animal sources and is made up of amino acids. High biological value (HBV) protein contains all essential amino acids and can be found in eggs, dairy, meat, and soy. Essential amino acids and the amino acid called leucine have shown to play the biggest role in MPS and reducing MPB (1) (2)
TIMING: Recent research suggests getting in protein within 3 hours post exercise and to contain adequate protein intake for up to 24 hours post exercise in order to achieve peak protein synthesis (1).
HOW MUCH: This depends on your weight, age, frequency and type of exercise and any chronic diseases present. The recommend daily protein intake for athletes is 1.2-2.0 g of protein/kg body weight (1)(3). Now back to timing, consuming protein in amounts of 20-40 g throughout the day can maximize protein synthesis (1). This large range of 20-40 g of protein is dependent on your body weight and amount/type of exercise.
Make an appointment with your local dietitian to find out your personal protein needs J
(1) Jager, R., Kersick, C. M., Campbell, B. I., Cribb, P. J., Wells, S. D., Skwiat, T. M., . . . Furnando, A. A. (2017). International Society of Sports Nutrition position stand: Protein and exercise. Journal of the International Society of Sports Nutrition. Retrieved June 3, 2019, from https://jissn.biomedcentral.com/articles/10.1186/s12970-017-0177-8.
(2) Sports Dietitians Australia (SDA). (2018). Protein Supplementation. [online] Available at: https://www.sportsdietitians.com.au/factsheets/supplements/protein-supplementation/ [Accessed 4 Jan. 2019].
(3) Eatright.org. (2017). Protein and the Athlete - How Much Do You Need?. [online] Available at: https://www.eatright.org/fitness/sports-and-performance/fueling-your-workout/protein-and-the-athlete [Accessed 4 Jan. 2019].