How important is the timing of proteins (for the elderly)?

How Much Difference Does the Moment You Eat Proteins Make?

"Drink your protein shake within 30 minutes after your workout!" This is one of the most persistent myths in the world of sports. The so-called 'anabolic window' – the magical time frame in which your muscles are said to crave proteins – has led millions of athletes to run to the locker room with their shaker in hand. But as is often the case in sports nutrition, reality is more nuanced than the marketing would have us believe.

The leucine story: a biochemical discovery

To understand why the timing of proteins is even up for debate, we need to go back to the basics of muscle building: the mechanistic target of rapamycin (mTOR) signaling pathway. This cellular switch determines when your muscles actually start producing new proteins.

The discovery that the amino acid leucine plays a unique role as a 'switch' for muscle protein synthesis was groundbreaking. Unlike other amino acids that mainly serve as building blocks, leucine acts as a metabolic signal. It activates the mTOR pathway, which then initiates the production of new muscle proteins.

Leucine vs strength training

Leucine may activate the muscle-building mTOR system, but without strength training, you won't gain an ounce of muscle mass. In other words, the muscle-building stimulus you get from strength training is much greater than that of a protein-rich meal. However, you still need to consume enough proteins to support that growth stimulus from the gym. Because the opposite is also true. Without proteins (and enough) calories, your muscles won't grow after your strenuous sessions at the gym.

The age threshold: why timing becomes more important with age

This is where it gets interesting. Young adults (under 30) show an almost linear response of muscle protein synthesis in relation to the amount of protein in a meal. Give a twenty-year-old 10 grams of protein and you get a certain response. Give him 20 grams and the response roughly doubles.

But older adults (65+) work differently. They need a 'threshold effect': only at about 2.8 grams of leucine per meal (equivalent to about 25-30 grams of high-quality protein) do you get a decent muscle protein synthesis going.

This explains why much research focuses on protein distribution in older adults. One study showed that 68-year-old women retained more muscle mass when their daily protein was concentrated in one large meal (51 grams) rather than divided into four smaller meals.

In short: if you're 70+ and only eat 15 grams of protein for breakfast, you're probably wasting your time. You won't reach the leucine threshold and muscle protein synthesis will remain at zero.

Dutch reality: we eat too little at breakfast

Research on Dutch older adults shows that protein intake is lowest at breakfast. Only 15-21% of daily proteins are consumed at breakfast, while dinner accounts for 38-44%.

This pattern is problematic because 25-30 grams of protein per meal is recommended to maximally stimulate muscle protein synthesis in older adults. In Dutch data, we see an average of less than 12 grams of protein at breakfast – substantially below the recommended 20-gram minimum.

Younger vs older adults: different rules

For athletes under 40, the rules are fairly simple:

It doesn't matter when you eat your meals, as long as you get enough protein throughout the day. For optimal muscle growth, aim for about 1.8 grams of protein per kg of body weight each day. Divide this into portions of 20-40 grams, with 3-4 hours in between.

The situation becomes more complex as you age. Older adults have 'anabolic resistance' – their muscles respond less sensitively to protein. This can be overcome by higher amounts of protein/amino acids. Several studies suggest that 25-30 grams of high-quality protein are needed to reach the threshold for maximum stimulation of muscle protein synthesis in older adults.

What works in practice: concrete advice

For athletes under 40:

• Aim for 1.6-2.2 grams of protein per kg of body weight per day

• Divide this into 3-4 meals

• Timing around training is not crucial, as long as your total is correct

For people over 50:

• Increase your daily intake to 1.0-1.2 grams per kg of body weight

• For active older adults (40-50+), aim for 1.1-1.5 grams per kg

• Ensure at least 25-30 grams of protein at breakfast

• Don't limit yourself to small protein portions – concentrate your protein in fewer, larger meals

Always engage in strength training:

To reiterate. Without strength training, you can eat as much protein as you want, but the 'stimulus threshold' for muscle building is only reached after a good training session. For muscle maintenance, in older adults, the breakdown process slows down by consuming meals with more proteins. However, for a real halt to muscle breakdown, or even building, older adults will also need to hit the gym.

Dutch guidelines: conservative but safe

The Dutch Health Council has not found evidence that all older adults need more protein than younger individuals. However, the council does not rule out that specific subgroups of older adults, such as vulnerable or malnourished elderly, may benefit from more protein.

This is a cautious approach. The international consensus literature is clearer: older adults need more protein to maintain and recover muscle mass and function. Note, do not change your diet independently. Have a conversation with a dietitian.

The bedtime strategy

An interesting development is research on protein intake just before bedtime. Protein intake before sleep can promote muscle protein synthesis during the night, ultimately resulting in an increase in muscle mass. 20-40 grams of protein before bed prevents you from losing muscle mass while you sleep.

Casein protein from dairy stimulates nighttime recovery and building processes the best. A bowl of cottage cheese with some fruit is a great choice for the evening.

For young people, this strategy adds little, as long as they meet their total protein needs.

Nonsense or fact? The nuance

Let's be honest: for the average recreational athlete who just wants to build some muscle, the timing of protein is not a game-changer. Total daily protein intake is much more important than when you eat it.

But there are exceptions:

• Older adults: smart protein distribution can indeed make a difference

• People with poor appetite: concentrating protein in fewer meals can help

• Athletes with extremely high training stress: optimal timing can make the last percent difference

The bottom line

Recent research shows that immediate protein intake before and/or after training is not relevant for muscle growth. It doesn't matter when you eat your meals, but when the nutrients are in your blood.

For most people: don't worry about the timing, but make sure you get enough protein. Spreading it throughout the day is useful, not because there's a magical window, but because it helps you reach your total without overeating.

And as you age? Then the story becomes more nuanced. Concentrate your protein, ensure enough at breakfast, and remember that 0.8 grams per kilo may simply be too little if you want to maintain your muscles.

Bronnen

1. Nunes, E. A., Colenso-Semple, L., McKellar, S. R., et al. (2022). Systematic review and meta-analysis of protein intake to support muscle mass and function in healthy adults. Journal of Cachexia, Sarcopenia and Muscle, 13, 795-810.

2. Hettiarachchi, J., Reijnierse, E. M., Kew, N., et al. (2024). The effect of dose, frequency, and timing of protein supplementation on muscle mass in older adults: A systematic review and meta-analysis. Ageing Research Reviews, 99, 102325.

3. Layman, D. K. (2024). Impacts of protein quantity and distribution on body composition. Frontiers in Nutrition, 11, 1388986.

4. Tieland, M., Borgonjen-Van den Berg, K. J., van Loon, L. J., et al. (2012). Dietary protein intake in community-dwelling, frail, and institutionalized elderly people: scope for improvement. European Journal of Nutrition, 51, 173-179.

5. Moore, D. R., Churchward-Venne, T. A., Witard, O., et al. (2015). Protein ingestion to stimulate myofibrillar protein synthesis requires greater relative protein intakes in healthy older versus younger men. The Journals of Gerontology, 70, 57-62.

6. Arnal, M. A., Mosoni, L., Boirie, Y., et al. (1999). Protein pulse feeding improves protein retention in elderly women. American Journal of Clinical Nutrition, 69, 1202-1208.

7. Gezondheidsraad Nederland (2021). Dietary reference values for proteins. Advisory report. Den Haag: Gezondheidsraad.