Does protein supplementation increase your resistance training gains in strength or muscle mass?
Resistance training in combination with protein supplementation is a common practice used by athletes around the world to enhance the “gains” experienced from doing their training. This makes sense as you need to provide fuel in the form of amino acids (which are the building blocks of protein) to muscles after a workout to lay down more muscle or help it recover. Additionally, it is starting to become very well recognised that as we age our capacity to process the protein in our diet to maintain our lean muscle mass (LMM) is not as efficient as when we are younger. Therefore, people aged 40+ in age typically need to consider taking in more protein per meal and throughout the day, otherwise they further risk sarcopenia developing as they age.
Now is this all marketing hype or is there any real science to back this up?
A recent meta-anlaysis conducted by Morton, R.W et al, 2017 combined 49 studies with a total of 1863 participants to determine the relationship between total protein intake and changes in LMM of individuals who do resistance training from a variety of individuals (trained vs untrained and youth vs older in age).
Data from the meta-analysis and 49 studies showed that dietary protein supplementation significantly (all p<0.05) increased changes in one repetition maximum (1RM) in a variety of strength exercises, lead to an increase in LMM and muscle size, as well as cross sectional area during periods of prolonged resistance training. The studies had to have a minimum of 6 weeks resistance training to be included. These positive results occurred when resistance training was done in conjunction with protein supplementation compared to resistance training alone.
The data from this analysis shows that protein supplementation is both sufficient and necessary to optimise resistance training increases in strength and LMM. Therefore, we can finally put to bed if we need to think about our protein intake if we want to increase our strength and lean muscle mass. This meta-analysis proves without a doubt that if you do not consider increasing your protein intake you will get inferior results. Period.
Increases in lean muscle mass were more effective in resistant trained individuals, less effective with increasing age and did not increase beyond total protein intakes of 1.6g/kg/day. Individuals who already do resistance training already have some adaptation to the exercise. Now we all know that as we start something new our bodies adapt quickly to the exercise and big gains are typically experienced, but as time goes by it is harder to make gains and changes hence why resistance trained individuals may have “less degree of freedom” to change and therefore have a greater need for protein supplementation to see further increases in muscle mass.
Additionally older individuals are anabolically resistant and require higher per meal protein doses to achieve similar rates of protein synthesis in comparison to younger individuals. Unfortunately, many studies in the literature currently prescribe a low dose of 20g/day to older individual with resistance training. It is likely that older individuals would be more responsive if given higher doses in future studies.
My key take home messages from this study are as follows. Firstly, you must consider how much protein you take in over the course of the day, in the youth 20-30g of protein post exercise is recommended, while in the 40+ age group 40g post exercise is more recommended. Additionally, if you want to put on muscle size and develop strength you need to push close to taking in 1.6g protein/kg/day. So if you weigh 70 kg that is 112g per day. In this review taking in above this tended to lead to a plateau in the gains experienced.
I hope this help and if you have any questions please email me at firstname.lastname@example.org
Reference: Morton, RW et al. A systematic review, meta-analysis and metaregression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults. Br J Sports Med 0: 1-10, 2017.