(3) The Ageing Ultrarunner Needs More Protein Than They Realise

Ultrarunning is already a masters sport

Ultrarunning has an older participation profile than most endurance sports. Western States data put the mean participant age near 45, while the fastest runners have tended to be in their late thirties or forties. That makes age-specific recovery questions practically important. The best current protein evidence supports using about 1.8 g/kg/day as a starting point for endurance athletes, but direct requirement studies in masters ultrarunners do not exist. The target is more defensible than generic adult guidance, not a precision prescription for every older runner.

Where the protein gap sits

A 2025 Sports Medicine review by Witard, Hearris and Morgan synthesised indicator amino acid oxidation studies and advocated about 1.8 g/kg/day. Reported habitual intake across male and female endurance athletes is nearer 1.5 g/kg/day, although an average cannot establish that most individuals are deficient. In a survey of 182 Australian triathletes, Doering and colleagues found that masters athletes consumed about 0.3 g/kg after exercise versus 0.4 g/kg in younger athletes; roughly 44% of the full sample answered that they did not know the recommended post-exercise protein intake. The practical gap is therefore plausible, but it should be assessed from an athlete's actual diet rather than assumed from age.

Ageing and muscle remodelling

Doering et al. tracked integrated myofibrillar protein synthesis in trained masters triathletes (mean age about 53) and younger trained triathletes (about 27) across three days of intensified endurance training. Both groups consumed roughly 1.6–1.7 g/kg/day, yet fractional synthesis was lower in the masters group: 1.49% versus 1.70% per day. The finding supports some age-related blunting despite long-term training, although it does not show that eating more would remove the difference. McKendry et al. later found comparable integrated synthesis rates in endurance-trained masters athletes and untrained older controls. That comparison suggests lifelong training did not raise this particular measure above the older control group; it does not establish what either group's youthful baseline had been.

The strongest counterargument

Daniel Moore's 2021 review makes a strong counterargument: masters athletes often resemble younger trained athletes more than sedentary older adults, so applying clinical ageing data can exaggerate their needs. The evidence behind the 1.8 g/kg/day target also comes mainly from very small studies in trained younger men; the Witard review notes that no indicator amino acid oxidation study has established requirements in older masters endurance athletes. The Doering data still justify attention to remodelling after damaging exercise, but they do not justify an age-specific dose above 1.8 g/kg/day. That boundary matters more than the appeal of a tidy number.

Total energy availability is an equally important confounder. A runner who under-eats across a heavy week can record a high protein percentage while still consuming too little absolute protein, carbohydrate and energy. Conversely, an athlete already meeting energy needs with varied meals may reach an adequate protein intake without supplements. The useful assessment is grams per kilogram across several representative days, interpreted alongside the training block, not the protein percentage shown by a single food-tracking screen.

What the evidence supports

The Witard review proposes about 1.8 g/kg/day on training days, around 1.95 g/kg/day during carbohydrate-restricted work and more than 2.0 g/kg/day on recovery days. Those higher estimates came from samples of six to eight trained men, so they are signals for periodisation rather than universal thresholds. Preliminary evidence supports about 0.5 g/kg in an immediate post-exercise meal; for a 70 kg runner that is 35 g. Trommelen et al. also found that 45 g of either whey or casein before sleep increased overnight mitochondrial and myofibrillar protein synthesis after cycling, compared with placebo. That trial involved 36 healthy young men, not masters ultrarunners, and measured acute synthesis rather than recovery or performance.

Distribution is useful mainly because it makes the daily target achievable. Three or four meals containing a meaningful protein dose are more practical than correcting a large deficit before bed. Food quality and tolerance still govern the choice: dairy, eggs, fish, meat, soy and mixed plant sources can all contribute, while athletes using predominantly plant proteins may need more attention to total dose and amino-acid variety. None of these choices should displace the carbohydrate required for the next long session.

The useful action is to audit a normal week before adding supplements. If intake clusters near 1.5 g/kg/day, move towards 1.8 by distributing protein across meals and protecting the recovery day after long descents, back-to-back runs or races. Higher targets deserve individual assessment when carbohydrate or energy availability is restricted. Protein belongs inside a broader durability and recovery plan; it cannot compensate for inadequate carbohydrate, total energy or sleep.

Sources

Ultramarathon demographics

1. Zingg, M.A., et al., "Analysis of participation and performance in athletes by age group in ultramarathons of more than 200 km in length" https://pubmed.ncbi.nlm.nih.gov/23589700/

2. Rüst, C.A., et al., "Analysis of performance and age of the fastest 100-mile ultra-marathoners worldwide" https://pubmed.ncbi.nlm.nih.gov/23778421/

3. Hoffman, M.D., & Wegelin, J.A., "The Western States 100-Mile Endurance Run: Participation and Performance Trends" https://doi.org/10.1249/MSS.0b013e3181a8d553

Protein requirements for endurance athletes

4. Witard, O.C., Hearris, M., & Morgan, P.T., "Protein Nutrition for Endurance Athletes: A Metabolic Focus on Promoting Recovery and Training Adaptation" https://doi.org/10.1007/s40279-025-02203-8

5. Jäger, R., et al., "International Society of Sports Nutrition Position Stand: Protein and Exercise" https://doi.org/10.1186/s12970-017-0177-8

6. Thomas, D.T., Erdman, K.A., & Burke, L.M., "Position of the Academy of Nutrition and Dietetics, Dietitians of Canada, and the American College of Sports Medicine: Nutrition and Athletic Performance" https://doi.org/10.1016/j.jand.2015.12.006

7. Wardenaar, F.C., et al., "Nutrient Intake by Ultramarathon Runners: Can They Meet Recommendations?" https://doi.org/10.1123/ijsnem.2014-0199

Masters athlete physiology

8. Doering, T.M., et al., "Lower Integrated Muscle Protein Synthesis in Masters Compared with Younger Athletes" https://doi.org/10.1249/MSS.0000000000000935

9. Doering, T.M., et al., "The Effect of Higher Than Recommended Protein Feedings Post-Exercise on Recovery Following Downhill Running in Masters Triathletes" https://doi.org/10.1123/ijsnem.2016-0079

10. Doering, T.M., et al., "Comparison of Post-Exercise Nutrition Knowledge and Post-Exercise Carbohydrate and Protein Intake Between Australian Masters and Younger Triathletes" https://doi.org/10.1123/ijsnem.2015-0289

11. McKendry, J., et al., "Comparable Rates of Integrated Myofibrillar Protein Synthesis Between Endurance-Trained Master Athletes and Untrained Older Individuals" https://doi.org/10.3389/fphys.2019.01084

12. Moore, D.R., "Protein Requirements for Master Athletes: Just Older Versions of Their Younger Selves" https://doi.org/10.1007/s40279-021-01510-0

13. Pérez-Castillo, I.M., et al., "Age-Related Anabolic Resistance: Nutritional and Exercise Strategies, and Potential Relevance to Life-Long Exercisers" https://doi.org/10.3390/nu17223503

14. Doering, T.M., et al., "Postexercise Dietary Protein Strategies to Maximize Skeletal Muscle Repair and Remodeling in Masters Endurance Athletes: A Review" https://doi.org/10.1123/ijsnem.2015-0102

Anabolic resistance

15. Wall, B.T., et al., "Aging Is Accompanied by a Blunted Muscle Protein Synthetic Response to Protein Ingestion" https://doi.org/10.1371/journal.pone.0140903

16. Durham, W.J., et al., "Age-related anabolic resistance after endurance-type exercise in healthy humans" https://doi.org/10.1096/fj.09-150177

17. Witard, O.C., et al., "Myofibrillar muscle protein synthesis rates subsequent to a meal in response to increasing doses of whey protein at rest and after resistance exercise" https://doi.org/10.3945/ajcn.112.055517

18. Yang, Y., et al., "Resistance exercise enhances myofibrillar protein synthesis with graded intakes of whey protein in older men" https://doi.org/10.1017/S0007114511003412

Pre-sleep protein and distribution

19. Trommelen, J., et al., "Pre-sleep Protein Ingestion Increases Mitochondrial Protein Synthesis Rates During Overnight Recovery from Endurance Exercise" https://doi.org/10.1007/s40279-023-01822-3

20. Trommelen, J., et al., "The anabolic response to protein ingestion during recovery from exercise has no upper limit in magnitude and duration in vivo in humans" https://doi.org/10.1016/j.xcrm.2023.101324

21. Reis, C.E.G., et al., "Effects of pre-sleep protein consumption on muscle-related outcomes" https://doi.org/10.1016/j.jsams.2020.06.010

Masters athletes and nutrition intake

22. Guo, S., et al., "Dietary Intake of Masters Athletes: A Systematic Review" https://doi.org/10.3390/nu15234973

23. Methenitis, S., et al., "The importance of protein intake in master marathon runners" https://doi.org/10.1016/j.nut.2021.111154

Leucine and dose response

24. Szwiega, S., et al., "Dietary leucine requirement of older men and women is higher than current recommendations" https://doi.org/10.1093/ajcn/nqaa258

25. Pinckaers, P.J.M., et al., "Dose-response effects of dietary protein on muscle protein synthesis during recovery from endurance exercise in young men" https://doi.org/10.1093/ajcn/nqaa073

Applied reference

26. Moore, D.R., "Protein Requirements of Master Athletes" (Gatorade Sports Science Institute) https://www.gssiweb.org/expert-panel/sports-medicine-publications/article/protein-requirements-for-master-athletes-just-older-versions-of-their-younger-selves