Scientists at the McMaster University in Canada recently poured over dozens of research studies in their quest to put the age-old debate over the effectiveness of protein supplements to rest.
It was the largest meta-analysis study of its kind, with researchers combing through a total of 49 high-quality studies with 1,863 participants, including men and women, young and old, and experienced weight lifters as well as novices.
Scientists aggregated the results from studies of weight training and protein, using databases of published research. They looked at experiments that had lasted at least six weeks and included a control group and the measurement of participants’ protein consumption as well as the impact on muscle size and strength.
According to Stuart Phillips, lead author of the comprehensive scientific research review, the findings of which were published in the British Journal of Sports Medicine, older lifters have far greater protein requirements to maintain muscularity as they age, and supplementing is an efficacious approach to meeting those needs.
There’s a limit
“The amount of protein recommended by international guidelines is not sufficient to maintain muscle size and strength, especially in older men,” says Phillips. Other studies have also shown that lifters, especially past the age of 40, who eat the most protein have the strongest and largest muscles. They also lose the least amount of muscle over time.
It is common knowledge that athletes need more protein than the regular recommended daily allowance. Research has, however, identified an upper limit to the amount of protein that can be consumed on a daily basis. The maximum amount is 1.6g of dietary protein per kilogram of bodyweight per day.
Slow muscle loss
The current protein recommended daily allowance (RDA) by the World Health Organisation (WHO) is 0.8g per kilogram of body weight. Phillips believes the WHO protein requirements are insufficient to maintain strength or muscle size. “Protein must be a big part of what you think about when you plan your meals. The prescribed 0.8g/kg/day just isn’t enough.”
More advanced lifters and strength athletes should consume high quality protein at every meal to support muscle health. “Protein is essential for all tissues in the body, providing amino acids that are important for growth and development. It is particularly important when you get older to help slow down the loss of muscle.”
High-quality protein supplementation, such as milk-based casein and whey protein, can spare muscle and promote gains during intense training, or when following a calorie-restrictive diet.
Timing not critical
When is the best time to consume protein? “Anytime in the ensuing 24 hours after a workout is a good time to eat protein,” says Phillips.
“Work from our research group has shown that your muscle is ‘sensitised’ to the effect of protein for at least 24 hours after a workout. I agree that the time from at least immediately to 3 hours post-exercise is a time when your muscle is even more sensitive to protein. However, it’s not a big difference between that time window and much later. While it’s still prudent to consume your shake immediately post-workout, it’s not critical.”
Phillips points out lifters should rather pay attention to the three “R’s” after exercise – rehydrate, replenish (muscle glycogen), and repair (damaged proteins). “Effective adaptation to training will occur only if all three R’s are attended to.”