Supplements in running: what's being used and what the research says
We report what runners are using and what the research says. We don't recommend taking any supplement. Talk to your GP or a registered sports dietitian before trying one.
One page per supplement: what it is, what studies found at each race distance, what the studies used, side effects, and where it stands with anti-doping rules. Every claim links to its reference. Ratings are marked as proposed until an expert reviewer confirms them.
Every supplement, in brief
Performance
Sodium bicarbonateResearch: Emerging (proposed, awaiting expert review)
A small benefit in short, hard efforts across sports; running-only trials are less clear. Stomach upset is common.
CreatineResearch: Weak (proposed, awaiting expert review)
Strong evidence for strength and repeated sprints; for distance running, trials show no benefit, and loading adds 1 to 2 kg.
CaffeineResearch: Strong (proposed, awaiting expert review)
Longer time to exhaustion and slightly faster time trials in a meta-analysis of runners; responses vary, and it can disrupt sleep.
Beta-alanineResearch: Emerging (proposed, awaiting expert review)
A small benefit in hard efforts of about 1 to 4 minutes after weeks of daily use; little evidence for longer races.
Beetroot and nitratesResearch: Emerging (proposed, awaiting expert review)
Longer time to exhaustion in lab tests, but no clear benefit in time trials or in well-trained runners. Can turn urine pink.
Fuelling
Electrolytes and sodiumResearch: Emerging (proposed, awaiting expert review)
Can help replace sweat losses in long, hot events; extra sodium hasn't been shown to prevent cramps or low blood sodium.
Carbohydrate fuellingResearch: Strong (proposed, awaiting expert review)
Gains in longer races from carb loading and from gels and drinks during the race; mixed for runs of about an hour. Gut problems are common.
Health and recovery
Vitamin DResearch: Weak (proposed, awaiting expert review)
No running performance gain in trials, even after low levels were corrected. The NHS says everyone should consider one in autumn and winter.
Omega-3Research: Emerging (proposed, awaiting expert review)
No faster times in the one trial that timed runners, and an inconsistent effect on soreness after hard exercise.
IronResearch: Emerging (proposed, awaiting expert review)
Gains shown only when iron is low, mostly in women; no benefit when iron is normal. Sports bodies say low iron should be confirmed first.
ProteinResearch: Emerging (proposed, awaiting expert review)
Food usually meets runners' protein needs. Extra protein hasn't clearly improved race performance; recovery and training results are mixed.
CollagenResearch: Emerging (proposed, awaiting expert review)
Two small, industry-part-funded trials found bigger gains in a 1-hour run. Tendon and strength effects alongside training are uncertain.
Hype check
Peptides (BPC-157 and TB-500)Research: Banned (proposed, awaiting expert review)
Prohibited in sport at all times. Almost all the research is in animals; there are no controlled trials in athletes.
KetonesResearch: Weak (proposed, awaiting expert review)
No performance benefit in meta-analyses or running trials, and some trials found slower times. Stomach upset is common.
