Many sports supplements make dramatic promises about improving performance, but only a few of them are supported by solid studies. In the first in a five-part supplement series, I examine the evidence for whey protein.
What exactly is it?
Whey protein is by far the most researched substance for muscle growth. It is a byproduct of cheese production that contains all nine essential amino acids and is swiftly digested and absorbed into the bloodstream, allowing it to reach muscles quickly.
What exactly does it do?
“The major benefits for athletes include speedier recovery, increased muscle synthesis, and retention of muscle mass during periods of low energy intake,” says James Morton, researcher at John Moores University and Team Sky’s chief nutritionist. “Our riders drink a whey shake before and after long [five to six-hour] rides to prevent excessive muscle protein breakdown.” Whey contains a lot of leucine, which is a vital signal molecule for initiation as well as a key substrate for muscle protein synthesis (MPS). Because of its high glutamine concentration, whey may also assist improve immunological function.
What is the proof?
Whey supplements may assist boost MPS after resistance training. In one study, participants who took 20 g of a whey and casein supplement before and after resistance training increased their muscle mass and strength more than those who took a placebo during a 10-week period.
Another study discovered that athletes who took a whey supplement immediately before and after a training session could execute more reps and lift heavier weights 24 hours and 48 hours later than those who took a placebo. Whey protein, on the other hand, may hasten muscle recovery after endurance activity. “We’ve shown that consuming whey protein soon after endurance exercise improves the remodelling of contractile muscle proteins throughout the early recovery period,” says Oliver Witard, a researcher at the University of Stirling.
Stirling researchers discovered that 20g whey protein was the ideal dose for optimising muscle regeneration after exercising in a trial involving 48 individuals. This is a rough estimate; if you weigh more than 80kg (the weight of the study’s athletes), you may require more, and vice versa. Consuming more than 0.25g/kg body mass results in no additional bulk growth; the excess is oxidised and used as an energy substrate.
However, in studies when participants were already getting enough protein from their diet, taking whey supplements before and after workouts had no effect on MPS or strength.
If you obtain enough protein from meals, there’s probably no need to take supplements. Milk (which naturally contains whey) may be preferable because studies (here and here) have shown that it increases muscle synthesis after resistance training. However, if you have higher-than-average protein needs, whey protein may be a practical option to supplement your diet. Whey may be a better option than casein or soy for enhancing muscle protein synthesis in the immediate post-exercise period, but whether this extends over a longer period is unknown.
The benefits of whey include a high concentration of vital amino acids, a quick digestion rate, and a high leucine concentration.