There is one description I hear more than any other. You swing your legs out of bed, put the first foot down, and something under the heel bites. Twenty steps later it has eased off. By evening, after a day on your feet, it is back. That story, on its own, gets you most of the way to a diagnosis.

What the plantar fascia does, and what goes wrong

The plantar fascia is a thick band of connective tissue running from the underside of the heel bone forward to the base of the toes. It works like a tie-rod across the bottom of the foot: it holds the arch’s shape and it stores and returns energy every time you push off. It is loaded by your body weight thousands of times a day.

The name says inflammation, and for most people that is not really what is happening. When the tissue is examined, what is typically found at the heel end is degenerative change — disorganised collagen, small areas of tissue breakdown, poor repair — rather than an angry inflammatory process. Specialists increasingly call it plantar fasciopathy or plantar heel pain for that reason. This is not a naming quibble. It is why the treatments that reliably help are the ones that load the tissue and give it a reason to remodel, and why treatments aimed purely at damping inflammation give short-lived relief.

How to recognise it

Four features do most of the identifying:

If your pain sits at the back of the heel rather than underneath it, this is probably not your page — see Achilles tendonitis. If it is dead centre and feels like a deep bruise, or it burns and tingles, or it is getting worse with activity rather than warming up, the heel pain by location guide covers the alternatives.

Why it hurts most in the morning

Overnight the foot rests in a slightly pointed position and the fascia and calf sit short. The tissue settles that way. The first steps of the morning stretch a structure that has spent eight hours shortened and has some damage in it, and it protests. As you walk, the tissue lengthens and the pain quietens. That is also the reasoning behind night splints, which hold the foot at a right angle so the first step is not such a shock — they help some people considerably and are tolerated by others not at all.

What causes it

Almost always a mismatch between what the tissue was ready for and what it was asked to do. The recognised contributors:

• A tight calf. Limited ankle dorsiflexion is one of the most consistently reported associations. A calf that will not lengthen forces the midfoot and fascia to absorb more.
• A jump in load. New job on your feet, a return to running after time off, a house move, a holiday of long walking days, a change of surface.
• Body weight. Higher BMI is a well-documented risk factor, particularly in people who are not athletes.
• Prolonged standing, especially on hard flat floors in unsupportive shoes.
• Foot shape — a very flat or a very high arch both change how the fascia is loaded, though shape alone rarely explains it.

Age matters too: it is most common in middle age, though runners get it younger.

How long it takes

Here is the honest version. Most plantar heel pain resolves without surgery, and the frequently quoted figure is that around nine in ten people are better within a year of appropriate treatment. That is genuinely reassuring and also frustrating, because a year is a long time to have a sore heel.

We will not give you a personal timeline, because nobody honestly can. What we can say is what usually shifts the curve, and that is the treatment page.

What to do first

1. Stretch the fascia itself, not just the calf. Sitting, cross the sore foot over the opposite knee, pull the toes back toward the shin with one hand until you feel the band tighten under the arch, and hold. This plantar-fascia-specific stretch has trial evidence behind it and is done several times a day, including before the first steps out of bed.
2. Stretch the calf as well, both with the knee straight and with it bent, so both calf muscles are covered.
3. Take the spikes out of the load for a few weeks. Not rest — reduction. Keep moving, drop the thing that provoked it.
4. Wear supportive shoes indoors. Barefoot on hard kitchen and bathroom floors is where a lot of people undo their day’s progress.
5. Give it eight weeks before judging. Connective tissue does not remodel on a weekly timescale.

Common questions

Does plantar fasciitis go away?

For most people, yes — the majority recover without surgery, most within about a year of sensible treatment. But it rarely goes away by being ignored. What resolves it is a combination of loading the tissue deliberately, taking the aggravating load off for a while, and supporting the foot. Left entirely alone, a proportion of heels stay sore for years, and long-standing pain is harder to treat than recent pain.

What are the two main symptoms?

Pain under the heel that is at its worst on the first steps in the morning or after sitting, and tenderness at one specific point on the inside of the underside of the heel where the fascia attaches. Those two together are the classic presentation. Stiffness in the arch and pain that returns after a long day on your feet are common companions.

How should I walk with plantar fasciitis?

Normally, in supportive shoes, and rather less than the amount that flares it. Walking is not the enemy — total rest deconditions the tissue and the calf, and people who stop moving generally do worse. What helps is avoiding the two extremes: long barefoot spells on hard floors, and long unbroken periods on your feet. Break walking into shorter bouts, put shoes on the moment you get out of bed, and back off the distance for a few weeks rather than stopping altogether. Limping to protect the heel loads the other leg and the knee, so if the pain is bad enough to change your gait it is time to get it looked at.

How do I repair the fascia?

You give it a reason to remodel and the conditions to do it in. Practically: the plantar-fascia-specific stretch daily, progressive calf strengthening, load management, and support underfoot. There is no injection, cream, supplement or device that repairs the tissue directly. Second-line treatments such as shockwave, corticosteroid injection and custom orthoses have a place when months of the basics have not worked — each has its own evidence and its own downside, which the treatment guide sets out.

Is the heel spur on my X-ray the problem?

Almost certainly not. Heel spurs are found in a good number of people with no heel pain at all, and spur size does not track with pain severity. The spur is a sign that the heel has been under sustained traction load for a long time — a footprint of the process rather than the cause of it. See heel spurs for the full picture.

Can I keep running?

Often, at reduced volume, if the pain settles within 24 hours after a run and is not getting worse week on week. Those are the two questions to ask yourself after each session. If pain is climbing, or lingering into the next day, the load is still too high — cut distance rather than stopping outright, keep the stretching going, and rebuild slowly. Pain that worsens progressively with running deserves an examination to rule out a calcaneal stress fracture.

Further reading

• Martin RL, Davenport TE, Reischl SF, et al. Heel pain — plantar fasciitis: revision 2014. Journal of Orthopaedic & Sports Physical Therapy, 2014 — the clinical practice guideline behind most of the above.
• DiGiovanni BF, Nawoczenski DA, et al. Plantar fascia-specific stretching exercise improves outcomes in patients with chronic plantar fasciitis. Journal of Bone and Joint Surgery, 2003 and 2006 follow-up — the trials behind the specific stretch described above.
• Riddle DL, Pulisic M, Pidcoe P, Johnson RE. Risk factors for plantar fasciitis: a matched case-control study. Journal of Bone and Joint Surgery, 2003 — the source of the calf-tightness and standing-occupation associations.