Visit a gym regularly and you’re bound to hear a conversation along the lines of: “I’ve just started my new whey protein shake. It says one scoop post-workout on the tub, but I take two just to make sure.”
Until now, sports nutritionists would have said you’re wasting your money. All the research has indicated that you need only one scoop (20g-25g) of high-quality protein whey or egg white to maximise the growth effects of a weight-training workout. Taking more has appeared to offer little if any additional benefit. This is why the dose recommended on the tub is usually one scoop per workout.
But recent work from our lab reveals otherwise. It raises the need for a major shift in sports nutrition recommendations. For many people, it looks like the gym logic may not be so far wrong after all.
The links between protein and resistance exercise are complicated. It is becoming clearer, though, that an amino acid found in higher levels in higher-quality proteins called leucine is intricately linked to muscle-building – or even the key amino acid in the process. Whey’s superiority to soy as a muscle-building protein has been attributed to its leucine content, for example.
What we found goes against a commonly accepted paradigm in sports nutrition. We showed that 40g of protein consumed post-workout was more effective than 20g of protein at stimulating the muscle-growth response.
This had nothing to do with the size of our participants, which made no difference to their protein requirement. It appears that the amount of muscle you work in a single session is more important to the optimal dose of protein post-workout than the absolute amount of muscle you possess – though it is important to stress that we did not explicitly test this question.
Though our data will require further validation, the results suggest that the recommended protein intake will in future depend on the nature of the preceding workout – along the lines of the graphic below:
It is also worth pointing out that the American College of Sports Medicine, the largest exercise science organisation in the world, specifically recommends that older adults perform full body resistance exercise workouts.
If our findings hold true for older adults, it may mean that they need to take even higher doses of protein to achieve optimal levels. Yet that might not be feasible for practical reasons – for example, you’d need to consume roughly two chicken breasts or about a litre of a thick shake to get 60g of protein. So instead of leading to changes in the nutrition, follow-up research may lead to older adults being recommended to change from performing a whole body routine to a split routine to maximise their muscle potential.