This guide is prepared by LøberLab. LøberLab specializes in evidence-based training and works to optimize runners' performance through the latest research and physiological knowledge.
Heel pain is among the most common injuries runners encounter – and also one of the most misunderstood. The standard advice often goes: "You have a heel spur, rest until the pain is gone." Both are usually wrong. In this guide, you'll get an overview of what really happens under the heel, why rest isn't the solution, and how to rebuild the fascia with the right combination of tailored running and strength training.
The Heel Spur is Not the Problem
A heel spur is a small calcium deposit on the heel bone, visible on X-ray. The name leads most to believe that a bone spur is poking up and irritating the foot. But research shows otherwise.
Studies have found heel spurs in up to a third of healthy people who have never had heel pain. The spur is not the cause of the pain – it is a consequence of long-term stress over many years. This also means that X-rays rarely change the treatment plan, and the latest clinical guidelines advise against routine imaging.
What actually hurts is the plantar fascia – the thick connective tissue under the foot that supports the arch and transfers force from heel to toes with each step. When the fascia receives more load than it can handle, it reacts with pain and microscopic degeneration. The condition is called plantar fasciopathy, and it's the diagnosis worth addressing.
Why the Fascia Gets Overloaded
It's almost always about a mismatch between load and capacity. And most often, it's the load that has increased too quickly. New research followed over 1,200 runners for a year and found that runners with more than 40 km per week had six times higher risk of developing plantar fasciopathy than those running 6-20 km weekly. This doesn't mean 40 km is a magic limit. The point is that volume increases must match the fascia's capacity.
Meta-analyses also point to higher BMI and body weight as consistent risk factors in physically active individuals. Additionally:
- Reduced ankle mobility. Tight calf muscles limit dorsiflexion and shift load onto the fascia.
- Insufficient calf strength. If the muscle doesn't absorb force during running, the fascia must compensate.
Note what's not on the list: specific shoe types, running style, and surfaces are not documented risk factors. It's rarely the foot that's "wrong." It's the balance between what the foot can handle and what it's exposed to.
Why Rest is Not the Answer
The common advice to rest until the pain is gone is problematic for one reason: the fascia doesn't get stronger by resting. It gets stronger by being loaded. In a progressive and controlled manner. When you stop all running for weeks or months, the fascia's tolerance decreases further. The pain disappears temporarily because the load is gone, but when you resume training, the capacity is lower than before, and symptoms return. This explains why so many runners experience the condition in a frustrating cyclical pattern.
The modern treatment logic is different: tailored load instead of absence of load. The fascia adapts to stress just like tendons and muscles and becomes stronger in the process.
How to Continue Running in a Tailored Form
Most runners with plantar fasciopathy can continue in a reduced form. Management is done via a simple pain scale from 0 to 10:
| Pain Traffic Light | |
|---|---|
| ●Green Light (0–2/10) | Continue as planned. Mild pain is acceptable. |
| ●Yellow Light (3–5/10) | Keep volume stable. Do not increase this week. |
| ●Red Light (over 5/10) | Limping or worsening: Reduce volume, intensity, or frequency. |
A typical build-up starts with three weekly runs of 15-20 minutes at a slow pace without speed and hills. From week 3-4, the duration is gradually extended to 20-25 minutes, still at low intensity. From week 5-8, the duration can be increased by 5 minutes per run per week, and a fourth weekly run can be added. Speed and intervals are reintroduced from week 9 onwards, once the base volume is stable.
A small adjustment with measurable effect: an increased cadence of 5-10% shortens stride length and reduces impact force through the fascia.
Strength Training is the Specific Intervention
While tailored running keeps the fascia active, it's strength training that actively builds capacity. A randomized study showed that heavy, slow heel raises provide faster pain improvement than stretching alone at 3 months follow-up. The effect persists at 12 months follow-up. It's the best-documented single intervention against plantar fasciopathy.
How to Perform the Heavy Heel Raise
Stand on the edge of a step on one leg with a rolled towel under the toes, so they are bent backward. This increases the load on the fascia. Slowly lift the heel over 3 seconds, hold briefly at the top, and lower in a controlled manner over 3 seconds until the heel is below step level. The exercise requires no equipment other than a step, a towel, and possibly a backpack with weight when you need to progress.
Progression Over 12 Weeks
- Week 1-4: 3 sets × 12 reps, body weight, every other day.
- Week 5-8: 4 sets × 10 reps with extra weight in a backpack or dumbbell.
- Week 9-12: 4 sets × 8 reps heavy, possibly supplemented with small hops in place to introduce faster force development.
Effective Dose: Load Beats Reps
The most common mistake is doing many, quick heel raises without weight. It doesn't work. The fascia adapts to mechanical strain – high load under controlled tempo – not the total number of reps. 20 quick reps without weight don't provide the same stimulus as 12 slow ones with load.
Two sessions a week are the minimum to build capacity, three are optimal. Consistency over time matters more than the intensity of a single session: A program consistently completed over 12 weeks beats a heavier program done sporadically a few times a month.
You know it's working when morning stiffness decreases, you can run longer before pain appears, and you lift more in heel raises than when you started. Keep going even after pain relief. Strength training is what prevents relapse. 1-2 sessions a week are sufficient for maintenance once capacity is built.
Supplementary Stretching
Stretching is not primary treatment but can relieve morning stiffness and supplement strength training. Do fascia stretches (sit down, cross foot over knee, bend toes backward for 30 seconds × 3 reps) and calf stretches against the wall (foot back, straight knee, heel on the floor, 30 seconds × 3 reps) – preferably in the morning before getting out of bed. Once daily is enough, twice if morning stiffness is significant.
Dosage: How to Put It All Together
The principle is simple: tailored running keeps the fascia active, strength training builds capacity, and stretching helps at the symptomatic level. It's the interplay that works.
| Frequency and Rhythm | ||
|---|---|---|
| Strength Training | 3–4 / week | Every other day |
| Running | 3–4 / week | In tailored form |
| Stretching | 1–2 / day | Preferably in the morning |
Weekly Composition: Preferably do strength training on the same day as your hardest run, so you consolidate the load and free up days for recovery. Avoid heavy strength training the day before you plan to test a longer or faster run.
When to Adjust: If morning stiffness decreases week by week, you can run longer before pain appears, and you lift more in heel raises than when you started – you're on the right track. If one good day is followed by two bad ones, reduce volume, not necessarily intensity.
Expect noticeable improvement within 8-12 weeks and full recovery over 6-12 months. The course is rarelylinearly.
Recovery: Sleep, protein, and time
The fascia doesn't build during training. It builds during recovery.
- Sleep: 7-9 hours with consistent bedtime. Poor sleep increases pain perception.
- Protein: 1.6-2.0 g per kg body weight daily supports connective tissue rebuilding.
- Rest: 48 hours between intense loads. Fascia and connective tissue recover slower than muscles.
- Moderate weight loss (if relevant): can noticeably reduce load per step.
What about shoes, insoles, shockwave, and cortisone?
Insoles and running shoes:
Can provide relief in the acute phase. Shoes with higher drop (10-12 mm) shift some load from the fascia, and good insoles can make daily life more bearable during active treatment. However, they don't build capacity and should be seen as tactical tools, not standalone strategies.
Massage, ice, and foam rolling:
Can temporarily reduce pain and stiffness. Cannot replace the active part of treatment.
Shockwave therapy (ESWT):
Stands out from other passive treatments. Meta-analyses show shockwave therapy is more effective than corticosteroid injections for pain and fascia thickness at both 3 and 6 months. Consider if symptoms persist beyond 3 months despite active treatment and should be combined with strength training.
Cortisone injections:
Provide quick pain relief, but the effect is short-lived, and repeated injections increase the risk of fascia rupture. Only relevant as a temporary supplement for severe pain.
Surgery:
Rarely necessary. Over 90% become symptom-free with conservative treatment, and surgery is typically considered only after 12 months of aggressive treatment without progress.
Summary: The 5 key points
- The spur is rarely the cause. It's the plantar fascia that hurts and can be trained stronger.
- Rest is not the answer. The fascia strengthens by being loaded, not spared.
- Adapted running combined with heavy, slow heel raises. It's the best-documented recipe.
- The process takes time. Expect 3 months for noticeable progress, 6-12 months for full recovery.
- Shoes, insoles, and passive treatment are supplements, not solutions. Use them tactically, not as a strategy.
Get well soon.
The article is prepared by LøberLab. Read more about their work at www.loberlab.dk.
Sources
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- Koc TA et al. Heel Pain – Plantar Fasciitis: Revision 2023. Clinical Practice Guidelines. JOSPT. 2023.
- Plesek J et al. Running Distance and Biomechanical Risk Factors for Plantar Fasciitis: A 1-yr Prospective Cohort Study. MSSE. 2025.
- Hamstra-Wright KL et al. Risk Factors for Plantar Fasciitis in Physically Active Individuals: A Systematic Review and Meta-- analysis. Sports Health. 2021.
- Rathleff MS et al. High-load strength training improves outcome in patients with plantar fasciitis: A randomized controlled trial with 12-month follow-up. Scand J Med Sci Sports. 2015.
- Cortés-Pérez I et al. Efficacy of extracorporeal shockwave therapy, compared to corticosteroid injections, on pain, plantar fascia thickness and foot function in patients with plantar fasciitis. Clinical Rehabilitation. 2024.
- Guimarães JS et al. Effects of therapeutic interventions on pain due to plantar fasciitis: A systematic review and meta-analysis. Clinical Rehabilitation. 2023.
