Creatine for runners: the hard days, not the pace

A runner's first question about creatine is whether it makes you faster. Over the distance, no: the trials in trained athletes find nothing. Where creatine does show up is on the hard days: the interval session, the closing kilometre of a race, and the morning after a long run. That is why runners take it, and why the dose that fits a runner is 5 g a day with no loading week.

The pace question, answered once

There is no reliable evidence that creatine makes trained athletes faster over an endurance distance. A 2023 meta-analysis by Fernández-Landa and colleagues in Sports Medicine pooled 13 controlled trials in trained athletes and found no effect on endurance performance.

VO2max is a no as well. The 2023 meta-analysis by Gras and colleagues, 19 randomised trials and 424 people, found VO2max rose in both groups but rose less with creatine than with placebo, a small gap but a statistically clear one. The 2023 review by Forbes and colleagues for the International Society of Sports Nutrition gives the reason: added body mass "may offset the potential positive effects, particularly in weight-bearing activities". The only running time trial in that review, a 1993 6 km terrain run, was slower with creatine, 23.79 against 23.36 minutes, with 0.9 kg more body mass.

Where it works: the interval session

Creatine's job in muscle is to refill phosphocreatine, the fuel for efforts of a few seconds to a minute, between one effort and the next. That is exactly what a track session or a set of hill repeats asks for. The International Society of Sports Nutrition's position stand lists interval training in endurance athletes among the events creatine may enhance, under faster phosphocreatine resynthesis.

Two trials tested it. Graef and colleagues, 2009, put 43 recreationally active men through 4 weeks of high-intensity interval training on a bike with 10 g of creatine citrate a day, five days a week, or placebo: ventilatory threshold, the intensity you can hold before breathing runs away, rose 16% with creatine against 10% with placebo, while VO2peak rose in both groups alike. In the companion trial from the same lab, Kendall and colleagues, 42 men on the same kind of programme raised their critical power, the highest output that can be held without fatigue, by 6.7% with creatine, while the placebo group's change was not significant. Both were cycling trials in men at 10 g a day, so read them as the mechanism working, not as a running result.

The last kilometre

Time trial results are mixed, and the Forbes review finds creatine most useful where a race asks for "multiple surges in intensity and/or during end spurts". In a 2018 trial by Tomcik and colleagues, 18 well-trained male cyclists on a loading dose rode a 120 km time trial no faster than the placebo group, but produced more power in its final 4 km sprint, despite gaining more weight. A 1996 rowing trial in the Forbes table took 2.3 seconds off a 1000 m row, all of it in the last two 200 m splits. For a runner that is the hill at 8 km and the finishing straight. The caveat is honest: those results are cycling and rowing at a loading dose, and no running trial has measured the end spurt yet.

The day after the long run

One trial in marathon-experienced runners found lower blood markers of muscle damage after a race. Santos and colleagues, 2004, gave runners with personal bests of 2.5 to 3 hours 20 g of creatine a day for 5 days before a 30 km race: the rise in creatine kinase, an enzyme that leaks from damaged muscle, was 19% smaller than in the control group, the runners reported no cramping, dehydration or diarrhoea, and all finished within 5.8% of their personal best. The abstract gives no participant count.

The meta-analyses are less generous. Northeast and Clifford, 2021, 13 studies and 278 people aged 20 to 60, found creatine kinase lower only at 48 hours and no effect on strength or soreness. Doma and colleagues, 2022, 23 studies with 240 people on creatine and 229 on placebo, found damage markers lower 48 to 90 hours after a single hard bout but higher at 24 hours with continued use through training. So: lower damage markers after one hard effort, and no reliable evidence yet that strength or soreness come back faster.

Glycogen is the clearer result. Roberts and colleagues, 2016, had 14 recreationally active men cycle to exhaustion, then eat about 8 g of carbohydrate per kg a day with 20 g of creatine or placebo for 6 days: after one day muscle glycogen stood at 410 mmol/kg dry muscle with creatine against 225 without, and the gap held to day 6. That is a 20 g a day figure. At 5 g a day, take the stick with a meal that has carbohydrate in it.

The kilo, and how not to gain it

The weight fear is a loading-week fact. Loading at 20 g a day for 5 to 7 days adds 1 to 3 kg, in the 2021 review by Antonio and colleagues, and the ISSN position stand calls weight gain the only consistently reported side effect and puts the loading-phase fluid at 0.5 to 1.0 litres. The Forbes review says weight-bearing athletes should skip loading, because 3 to 5 g a day fills the stores over 4 weeks, as Hultman and colleagues showed in 1996 in 31 men: 3 g a day for 28 days raised muscle creatine as much as 20 g a day for 6 days. The one measurement at 5 g a day, Desai and colleagues, 2025, in 63 untrained adults, found 0.5 kg more lean body mass than the control group after 7 days; total body mass was not reported. Where that water sits, inside the muscle rather than under the skin, is covered in the creatine and electrolytes article.

What it does when you are not running

Most of the reasons a runner takes creatine every day sit outside the run. The short-night and mental-fatigue studies are summarised on the cognitive page. The other half of the stick, sodium and potassium in daily-life doses, replaces part of what a sweaty session takes out, and the electrolytes article explains why water alone does not.

From today to race day

Start 5 g a day today, with a carbohydrate meal, and give it 4 weeks: that is the Hultman timeline for full stores at a maintenance dose. Race week changes nothing. Keep the same 5 g and start nothing new: in a 2024 randomised trial by Barranco-Gil and colleagues, 23 professional under-23 cyclists loaded 20 g a day for 7 days around a 6-day training camp and gained nothing over placebo. The Santos runners raced their 30 km on creatine and finished within 5.8% of their best.

A Dosys stick is 5 g of Creapure creatine monohydrate with 235 mg of sodium, 129 mg of potassium, 56.5 mg of magnesium as citrate (15% of the daily reference intake) and 1 g of taurine, unflavoured, stirred into water or the first coffee.

Five grams a day from today, no loading week, the same 5 g in race week. One stick a day, every day.

Sources

1. Fernández-Landa J, et al. Effects of creatine monohydrate on endurance performance in a trained population: a systematic review and meta-analysis. Sports Med. 2023;53(5):1017-1027. pubmed.ncbi.nlm.nih.gov
2. Tomcik KA, et al. Effects of creatine and carbohydrate loading on cycling time trial performance. Med Sci Sports Exerc. 2018;50(1):141-150. pubmed.ncbi.nlm.nih.gov
3. Gras D, et al. Creatine supplementation and VO2max: a systematic review and meta-analysis. Crit Rev Food Sci Nutr. 2023;63(21):4855-4866. pubmed.ncbi.nlm.nih.gov
4. Forbes SC, et al. Creatine supplementation and endurance performance: surges and sprints to win the race. J Int Soc Sports Nutr. 2023;20(1):2204071. pmc.ncbi.nlm.nih.gov
5. Kreider RB, et al. International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport, and medicine. J Int Soc Sports Nutr. 2017;14:18. pmc.ncbi.nlm.nih.gov
6. Graef JL, et al. The effects of four weeks of creatine supplementation and high-intensity interval training on cardiorespiratory fitness: a randomized controlled trial. J Int Soc Sports Nutr. 2009;6:18. pubmed.ncbi.nlm.nih.gov
7. Kendall KL, et al. Effects of four weeks of high-intensity interval training and creatine supplementation on critical power and anaerobic working capacity in college-aged men. J Strength Cond Res. 2009;23(6):1663-1669. pubmed.ncbi.nlm.nih.gov
8. Santos RV, et al. The effect of creatine supplementation upon inflammatory and muscle soreness markers after a 30km race. Life Sci. 2004;75(16):1917-1924. pubmed.ncbi.nlm.nih.gov
9. Northeast B, Clifford T. The effect of creatine supplementation on markers of exercise-induced muscle damage: a systematic review and meta-analysis of human intervention trials. Int J Sport Nutr Exerc Metab. 2021;31(3):276-291. pubmed.ncbi.nlm.nih.gov
10. Doma K, et al. The paradoxical effect of creatine monohydrate on muscle damage markers: a systematic review and meta-analysis. Sports Med. 2022;52(7):1623-1645. pubmed.ncbi.nlm.nih.gov
11. Roberts PA, et al. Creatine ingestion augments dietary carbohydrate mediated muscle glycogen supercompensation during the initial 24 h of recovery following prolonged exhaustive exercise in humans. Amino Acids. 2016;48:1831-1842. pmc.ncbi.nlm.nih.gov
12. Antonio J, et al. Common questions and misconceptions about creatine supplementation: what does the scientific evidence really show? J Int Soc Sports Nutr. 2021;18:13. pmc.ncbi.nlm.nih.gov
13. Hultman E, et al. Muscle creatine loading in men. J Appl Physiol. 1996;81(1):232-237. pubmed.ncbi.nlm.nih.gov
14. Desai I, et al. The effect of creatine supplementation on lean body mass with and without resistance training. Nutrients. 2025;17(6):1081. pmc.ncbi.nlm.nih.gov
15. Barranco-Gil D, et al. High-dose short-term creatine supplementation without beneficial effects in professional cyclists: a randomized controlled trial. J Int Soc Sports Nutr. 2024;21(1):2340574. pmc.ncbi.nlm.nih.gov