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Doctor-led · In a hospital · 2-minute quiz
AI-generated illustration based on a Cardiff race reference. Not an official event photograph.
How long does it take to recover from a half marathon?
Most runners find the worst of the soreness eases within three to five days, and feel back to normal within one to two weeks. Muscles and tendons carry on repairing for a while after they stop hurting, so keep the first week easy even if you feel fine by Wednesday.
It usually takes longer after a first half, patchy training, a hot day or a faster pace than you are used to. Recovery varies; sharp, localised or worsening pain needs checking.
What should I eat after a half marathon?
Within an hour or two of finishing, eat something with carbohydrate and some protein: a sandwich, a bagel with peanut butter, a glass of chocolate milk, or yoghurt with fruit all work. Then have a normal meal later in the day.
Drink to thirst. Water is fine, and if you sweated heavily, a sports drink or something salty helps replace what you lost. There is no need to force down extra water; drinking far more than you need can be dangerous. If you want a celebratory drink, have it after you have eaten and had some water.
Vegetarian or vegan? Soya milk, beans, lentils, tofu and nut butters do the same job.
When can I run again after a half marathon?
Take two or three days off running. Walking, easy cycling or swimming are fine if you want to move. Then try a short, easy run at a pace where you could chat, and build back up over the next week or two before any fast sessions or long runs.
If a run makes a pain worse, or makes you limp, stop and give it longer. If you have another race soon, your plan paces the return around it.
Why are my legs sorer two days after the race?
That is delayed-onset muscle soreness, or DOMS. Running further or faster than your muscles are used to, especially downhill, strains the muscle fibres, and the soreness usually peaks 24 to 72 hours later. It settles on its own.
Gentle walking, a good night's sleep and regular meals make those days more comfortable, and stairs will be hard for a day or two. Pain that is still getting worse after day three, or that sits on one spot of bone, needs checking: see when to worry, below.
Should I stretch, foam roll or get a massage?
Do whatever feels good, gently. Light stretching, a foam roller or an easy massage can make your legs feel looser, but none of them is essential. Leave deep or hard massage for a few days, and stop anything that causes sharp pain.
What should I do in race week?
Keep your runs short and easy, sleep as well as you can, and eat the foods you know. Try nothing new on race day: not new shoes, gels or breakfast. Plan how you will get to the start, because roads close early on race morning. Check your bib colour: the first waves start at 10:00, others at 10:10. Lay your kit out the night before.
When should I worry after a half marathon?
Most aches after a half marathon are normal. Get help if you notice any of these:
- Chest pain, fainting, a racing or irregular heartbeat, or severe breathlessness: Call 999.
- Confusion, a severe headache, vomiting or unusual drowsiness, especially if you drank a lot of water or sports drink: Get urgent help now: call 999 or go to A&E. It can mean the salt level in your blood has dropped too low.
- Dark, cola-coloured urine with severe muscle pain or weakness: Get urgent help today: go to A&E or call NHS 111.
- A painful, swollen or warm calf, especially after a long journey home: Get seen the same day: call NHS 111 or your GP.
- Pain in one spot on a bone that hurts to press or makes you limp: Stop running and see your GP or a physiotherapist.
If you are not sure, call NHS 111 or use 111 online.
What about hyperbaric oxygen?
Hyperbaric oxygen therapy (HBOT) means breathing concentrated oxygen while you sit in a pressurised chamber. Some runners and other athletes use it as part of their recovery.
The research on exercise recovery is limited and the results are mixed, so we won't promise it changes how your legs feel. Your plan works without it.
If you are curious, HBOT Medics is doctor-led and based inside RosMedics (Pontcanna Hospital) on Cathedral Road. No referral needed.
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Build my planHBOT Medics is not affiliated with Run 4 Wales or the Cardiff Half Marathon.