A claim you hear on longevity podcasts

Is the anabolic window a myth?

The claim checked: Total daily protein likely matters much more than eating it 30 to 60 minutes after training Hear it at 39:39

What do the studies say?

Leaning for

Seven of ten studies found total protein mattered more than timing for muscle. Two trials, one in bodybuilders and one in untrained older adults, found protein around training helped, and one study was mixed.

Computed from 10 studies that test this point, each judged by two readers, in full. 6 more studies are waiting for a full read and do not count yet.

What was said on the podcast?

“people talked about a narrow post-workout anabolic window. That's the time your muscles are primed for growth. So, the idea was to consume your protein within about 30 to 60 minutes after training. But we now know that the window is much broader. Your total daily protein intake is likely to matter much more than timing.”
David Sinclair, Lifespan · How to Exercise to Live Longer | Lifespan with Dr. David Sinclair - S2, Ep. 5 · 39:39 on YouTube
Comes up in 4 episodes of the show.
The point checked Leaning for

Total daily protein likely matters much more than eating it within 30-60 minutes after training (with a fasted/long-gap exception)

Agree 7

other primary study · 2013

“Any positive effects noted in timing studies were found to be due to an increased protein intake rather than the temporal aspects of consumption, but a lack of matched studies makes it difficult to draw firm conclusions in this regard.”

The effect of protein timing on muscle strength and hypertrophy: a meta-analysis. J Int Soc Sports Nutr
Who: randomized resistance-training studies in adults (trained and untrained, young 18-49 and elderly 50+) comparing protein within 1 hour pre/post workout vs protein distant from the session or none
PMID 24299050

pooled analysis · 2020

“Subgroup analyses showed no beneficial effect of a specific timing of protein intake on LBM, handgrip strength, and leg press strength.”

The Role of Protein Intake and its Timing on Body Composition and Muscle Function in Healthy Adults: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. J Nutr
Who: Free-living healthy adults (mean age 18-55) and older adults (>55), incl. some obese, frail or sarcopenic, in RCTs of protein supplementation or high-protein diets, mostly with resistance training
PMID 32232404

controlled trial · 2009

“Timed protein supplementation immediately before and after exercise does not further augment the increase in skeletal muscle mass and strength after prolonged resistance-type exercise training in healthy elderly men who habitually consume adequate amounts of dietary protein.”

Protein supplementation before and after exercise does not further augment skeletal muscle hypertrophy after resistance training in elderly men. Am J Clin Nutr
Who: healthy untrained elderly men aged 72 ± 2 y with habitual protein intake ~1.1 g/kg/d
PMID 19106243

Show 4 more Show fewer

other primary study · 2024

“Given that the current study did not identify any statistically significant differences between groups regarding muscular performance and SMM, it is critical to emphasize that any potential impact of protein timing on muscle hypertrophy, if it exists, seems to be relatively minor.”

Timing matters? The effects of two different timing of high protein diets on body composition, muscular performance, and biochemical markers in resistance-trained males. Front Nutr
Who: Resistance-trained males (mean age 24) in Tehran, Iran, with at least 1 year of training
PMID 38846541

controlled trial · 2018

“The major finding of the current investigation was that WP supplementation increased SMM, ULLST, and functional capacity in pre-conditioned older women, independent of the time of administration around each training session.”

Effects of Whey Protein Supplementation Pre- or Post-Resistance Training on Muscle Mass, Muscular Strength, and Functional Capacity in Pre-Conditioned Older Women: A Randomized Clinical Trial. Nutrients
Who: Pre-conditioned (8 weeks prior resistance training) Brazilian women aged 60+
PMID 29751507

pooled analysis · 2025

“Taking these limitations into account, we conclude that protein supplementation within the time window of 15 min pre-exercise to approximately 2 h post exercise does not significantly affect muscle strength and body composition.”

Does Protein Ingestion Timing Affect Exercise-Induced Adaptations? A Systematic Review with Meta-Analysis. Nutrients
Who: adults in resistance-training RCTs: young trained men, young trained women, older untrained men and women, and overweight/obese adults with type 2 diabetes
PMID 40647175

controlled trial · 2025

“The absence of group differences indicates that protein timing should not be emphasized when optimizing RET in this population.”

Neither pre-sleep nor post-exercise protein consumption influences resistance exercise training adaptations in older adults. J Int Soc Sports Nutr
Who: 30 untrained older men aged 60-75 (65.7 +/- 4.0 yr) with baseline protein intake >=1.0 g/kg/day
PMID 40539259

Partly agree 1

other primary study · 2018

“In conclusion, we report little influence of the pattern of protein ingestion over the day on the integrated rate of bulk MyoPS measured over 2 weeks of ER alone or 2 weeks of ER + RT in overweight/obese older men, although subtle differences in the pattern of individual protein synthesis rates in skeletal muscle were apparent between the dietary interventions.”

Effect of resistance training and protein intake pattern on myofibrillar protein synthesis and proteome kinetics in older men in energy restriction. J Physiol
Who: 20 overweight and obese but generally healthy older men (age 66 ± 4 years, BMI 31 ± 5) on a controlled hypocaloric diet
PMID 29532476

Disagree 2

controlled trial · 2006

“Supplement timing represents a simple but effective strategy that enhances the adaptations desired from RE-training.”

Effects of supplement timing and resistance exercise on skeletal muscle hypertrophy. Med Sci Sports Exerc
Who: Resistance-trained recreational male bodybuilders
PMID 17095924

controlled trial · 2017

“Therefore, when fulfilling the dietary recommendations, timing of protein intake seem to be more important than total protein intake.”

Effect of small-sided team sport training and protein intake on muscle mass, physical function and markers of health in older untrained adults: A randomized trial. PLoS One
Who: Untrained older men and women aged 65-90 (mean 72), Copenhagen
PMID 29016675

What else was said but not tested?

  • Optimal intake for most people is about 1.2-2 g/kg/day, higher for older adults and heavy trainers
  • Spreading protein across at least two meals can stimulate muscle protein synthesis more than one large dose

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