Determining how much protein you as an athlete should be eating and when you should be eating it is often a controversial and regularly discussed topic amongst strength athletes. This article will go over both of these topics and outline the information most important to you as a strength athlete.
Simply put, protein is the macronutrient needed in order to provide the body with structure. It provides the building material for muscle; the stimulus for driving the protein anabolic process, and maintenance of non-muscle structural tissues. Proteins, like carbohydrates, are worth 4 calories per gram energetically when oxidized in the human body. A calorie is a unit of measurement for the amount of energy contained in a nutrient.
How much protein a day?
Diets high in protein have been shown to generally improve body composition (Morales et al., 2017). Competitive powerlifters can generally benefit from improved body composition due to the fact that a leaner athlete will have a larger proportion of fat free mass to bodyfat – meaning that a greater amount of their overall bodyweight is made up of muscle that can be used to lift the most weight possible. It is widely accepted that the recommended daily intake of protein for strength athletes is higher than the amount recommended for the general public. The current protein recommendations for athletes are estimated to range between 1.2–2.0 g / kg body weight per day (Martinez et al., 2019) or can be rounded up to as high or higher than 1g / lbs of body weight per day. A meta-analysis by Cermak et al., (2012) showed that when increasing protein levels closer to the 2.0g / kg bodyweight mark in young adults, the additional protein enhanced both gains in strength and muscle mass from training.
Generally speaking, protein demands will vary based on size, gender, training style/intensity, and age. Taking these variables into account will help you to determine what your protein demands are. For example, it’s reasonable to expect that an individual resistance training with high intensity weighing 100kg will require more protein daily in comparison to an individual only performing cardio at a low intensity weighing 50kg.
We can look further into protein demands by considering timing of when we consume protein. For example in a post workout meal: it’s recently been shown that there’s a plateau in the post-exercise anabolic response of an athlete after consuming somewhere between a ~20g (Witard et al., 2014) and ~40g (Macnaughton et al., 2016) dose of high quality (e.g. whey or beef) protein. This suggests that it may be beneficial as an athlete to ensure you are eating somewhere between 20-40g of high quality protein post training in order to maximize the post-exercise anabolic response (growth and muscular recovery). The general consensus of scientific literature favours consistently elevating blood amino acids (ingesting a protein source including both non-essential and essential amino acids) and providing a nutrient energy source to drive muscle protein synthesis. Whilst we know that we need to eat enough protein to grow and recover, the protein synthetic response (muscle building and recovery) to elevated blood amino acid levels slows down after approximately 90 minutes and remains refractory. This means that elevated levels of protein synthesis can’t be maintained even if blood amino acid levels remain elevated. Given this, it makes sense to spread protein out throughout the day in doses of 20-40g (amount in each ‘dose’ depends on overall protein demands) in order to maximise the amount of times in the day we can elevate protein synthesis.
Protein sources matter!
Whilst protein timing is clearly an important factor to take into account, protein quality is also an important variable to take note of. Whey or milk based protein sources are largely more effective than soy for stimulating protein synthesis (Tang and Phillips, 2009). With this logic, we can see that different proteins can affect the amplitude and possibly duration of protein synthesis. The difference often noted between milk and soy is likely due to the high amount of leucine in whey, a component of milk. Naturally, animal protein sources like eggs and meat are considered high quality proteins and are rich in the essential amino acids as well as being highly digestible to most. The negative reputation of plant proteins is generally unsupported as they’re often combined with other more complete proteins that contain all the essential amino acids needed to stimulate muscle protein synthesis.
Too much protein?
The long-term safety of “high protein” diets has not been studied extensively – to the degree that there is often controversy surrounding the topic of daily total protein intake recommendations. Whilst there are studies to suggest there can be adverse effects relating to excessive protein intake,(above appx. 3.5kg / kg / day, this is well above the 1g / lbs / day figure that strength athletes often use as a standard.
One note worth making is that you need to consume enough high quality protein as well as enough calories to allow strength and muscle gains. Whilst studies have shown that increasing protein intake can improve body composition, others such as that done by Antonio et al., (2014) show that in resistance trained individuals, increasing protein from a range of 1.4 – 2.0g / kg / day to 4.4g / kg / day did not provide any significant change in fat free mass (muscle) or body composition. So whilst having enough protein is important, making sure that you are not massively exceeding your protein demands is important too!
Take home notes
Split protein up evenly throughout meals of the day
Ideally aim for 20-40g protein in each meal
Aim for approximately 1.2-2g/kg bodyweight or as high as 1g/lbs of bodyweight
More protein isn’t always better – assess your intake in comparison to your bodyweight and factors that influence your individual protein demands.
Protein sources matter - consumption of different proteins can affect muscle growth and recovery rate.
References
Antonio, J., Peacock, C.A., Ellerbroek, A., Fromhoff, B. and Silver, T., 2014. The effects of consuming a high protein diet (4.4 g/kg/d) on body composition in resistance-trained individuals. Journal of the International Society of Sports Nutrition, 11(1), pp.1-6.
Cermak, N.M., Res, P.T., de Groot, L.C., Saris, W.H. and van Loon, L.J., 2012. Protein supplementation augments the adaptive response of skeletal muscle to resistance-type exercise training: a meta-analysis. The American journal of clinical nutrition, 96(6), pp.1454-1464.
Macnaughton, L.S., Wardle, S.L., Witard, O.C., McGlory, C., Hamilton, D.L., Jeromson, S., Lawrence, C.E., Wallis, G.A. and Tipton, K.D., 2016. The response of muscle protein synthesis following whole‐body resistance exercise is greater following 40 g than 20 g of ingested whey protein. Physiological reports, 4(15).
Martinez, I.G., Skinner, S.K. and Burd, N.A., 2019. Protein Intake for Optimal Sports Performance. In Nutrition and Enhanced Sports Performance (pp. 461-470). Academic Press.
Morales, F.E., Tinsley, G.M. and Gordon, P.M., 2017. Acute and long-term impact of high-protein diets on endocrine and metabolic function, body composition, and exercise-induced adaptations. Journal of the American College of Nutrition, 36(4), pp.295-305.
Tang, J.E. and Phillips, S.M., 2009. Maximizing muscle protein anabolism: the role of protein quality. Current Opinion in Clinical Nutrition & Metabolic Care, 12(1), pp.66-71.
Witard, O.C., Jackman, S.R., Breen, L., Smith, K., Selby, A. and Tipton, K.D., 2014. Myofibrillar muscle protein synthesis rates subsequent to a meal in response to increasing doses of whey protein at rest and after resistance exercise. The American journal of clinical nutrition, 99(1), pp.86-95.