Do Cyclists Need To Worry About Protein Timing For Recovery?

At some point, you’ve probably heard that your muscles can’t use more than 20 grams of protein in a single meal, and therefore, consuming any more than this within a single meal is a waste.

Sports nutrition is a rapidly developing field, and more research is being completed and published constantly. This means that our understanding of optimising our diet for cycling performance continually evolves.

A landmark study published in December 2023 has made an enormous leap forward in our understanding of the impact of protein feeding on muscle growth and repair and has shown us that our muscles can absorb a whole lot more than 20 grams! Let me explain.

There is often some confusion about the difference between absorption and utilisation, so before we go any further, it’s important to distinguish between them.

Protein Absorption - This refers to the amount of protein that we can digest in our stomach. We don’t have exact figures for this, as many factors can influence the rate at which protein is digested (i.e. the type of protein eaten, other foods it’s digested with, etc). Still, generally, even if you consume a substantial meal of protein (100 grams of protein in a single meal would be a challenge to eat physically), almost all that protein will eventually be absorbed, although this will take some time (12 hours+).

 Protein Utilisation – This refers to how much of the protein we consume is taken up by the muscle and used for growth and repair in a process called muscle protein synthesis. This was previously thought to be limited, but with these new findings, that may not be true.

Up until recently, it was always thought that 20-25 grams of protein was enough to stimulate muscle protein synthesis maximally. If you consumed more than this, the extra wouldn’t be used by the muscle and would be diverted to oxidation (i.e. converted to glucose and used as a fuel), as beyond building new tissue, the body has no capacity to store excess protein.

This was referred to as the ‘muscle full’ hypothesis and meant that if you wanted to maximise muscle protein synthesis (the building of new muscle tissue), you would have to consume multiple feedings of 20-25grams of protein over the course of the day, allowing a refractory period between each feeding to allow muscle protein synthesis to return to baseline, before feeding with protein to stimulate it again.

However, a new study (https://pubmed.ncbi.nlm.nih.gov/38118410/) from a lab in the Netherlands has completely turned this advice on its head. The study took a group of recreationally active young males and, on separate occasions, fed them either 0, 25g or 100 grams of protein from dairy milk after a resistance training session and then measured muscle protein synthesis over a 12-hour period. The timeframe is important, as previously, much of the research has only measured muscle protein sythesis over a relatively short < 6-hour window.

The researchers chose 100 grams of protein, as based on their experience at their summer BBQ, consuming beyond 100 grams of protein in a single meal was quite a challenge to eat physically, so it’s unlikely the average person would consume more than this in a single meal. They also used dairy milk, as it is the most significant contributor to daily protein intake in the Western world. They also have a clever way of labelling the milk so they can follow its journey through the body and into the muscles.

What did they find? Interestingly, even at the end of the 12-hour period, the 100-gram protein dose was still being digested! They saw that the 100-gram dose of protein led to the most significant increase in muscle protein synthesis; this was 30% higher overall than the 25-gram dose over the 12 hours. The additional protein had a benefit in the early phase of recovery, but the main benefit came in the last 8 hours, where the 100-gram dose resulted in 40% higher rates of muscle protein synthesis. All doses of protein also lead to a very negligible increase in protein breakdown, particularly in comparison to the rate of synthesis.

What does this mean for us as cyclists?

As a cyclist, muscle protein synthesis is a crucial process for recovery and adaptation from training. If we want to become a better cyclist, we want to try and maximise this process post-exercise to ensure we get as much from each session as we physically can.

This study shows us that consuming above 20 grams of protein in a single meal certainly doesn’t result in protein being wasted.

Whilst we do want to ensure that we have an adequate intake of protein in the period post-ride and we want to avoid long periods without consuming protein, this study does show that we don’t necessarily need to pay as much attention as we thought to space our intake of protein through the day evenly and that our total protein intake over the course of the day is the most critical aspect of optimising dietary protein intake.

It’s also worth noting that large protein feedings potentially take a long time to break down, so if we are looking to complete a hard ride and avoid stomach issues, we should be mindful of large servings of protein in the hours before the session.

- Coach Ben