The Rathleff Protocol, Explained

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Spend enough time in heel-pain communities and one specific recommendation keeps surfacing — not a product, not a shoe, but a named exercise protocol:

"A large portion of users have been able to improve by using the Rathleff protocol (google it) — heel raises with a towel under the toes."

It gets recommended because it's specific, it's published, and it's built on the modern understanding of what this condition actually is. It's also frequently oversold, so this article does two things: explains exactly how to do it, and reports honestly what the trial found — including the part most write-ups leave out.

The idea behind it

If plantar heel pain is degenerative rather than inflammatory — collagen that has broken down and failed to repair properly, as the tissue studies indicate — then the treatment question changes. You're not calming something down. You're restarting a stalled repair process.

Across degenerative connective-tissue problems, the stimulus that reliably drives remodelling is progressive mechanical load: heavy, slow, controlled work that gives the tissue a reason to reorganise and strengthen.

That approach transformed the management of Achilles and patellar tendon problems. Rathleff and colleagues asked the obvious next question — does it work for the plantar fascia? — and designed an exercise to load it specifically.

The clever part is the towel. A plain calf raise loads the calf and Achilles but barely engages the plantar fascia. Put a rolled towel under the toes so they're held bent upward, and you engage the windlass mechanism — the fascia winds taut around the toe joints as you rise. Now the same movement loads the fascia under high tension.

Simple, mechanically precise, and it needs a towel and a step.

How to do it

Setup

  • Stand on a step or a thick book, with the ball of your foot on the edge and your heel hanging free
  • Place a rolled towel under your toes, thick enough that the toes are clearly bent upward. This is the part that makes it work — don't skip it
  • Single leg on the affected side (start double-leg if you can't yet control single-leg)
  • Hold a wall or rail for balance, not for assistance

The movement — and the tempo is the point

  • 3 seconds up — rise slowly onto the ball of your foot
  • 2 seconds hold at the top
  • 3 seconds down — lower slowly, all the way, until your heel drops below the step

Eight seconds per repetition. Slow is not a suggestion; the slow tempo is the treatment. Bouncing through the reps turns a loading exercise into a calf workout.

Volume and progression

The published protocol progressed load rather than repetitions, using a backpack loaded with books:

  • Start: 3 sets of 12 repetitions, every other day
  • Progress by adding weight and reducing reps: to 4 sets of 10, then 5 sets of 8
  • The target intensity is roughly the heaviest load you can control with good tempo for the prescribed reps

Every other day, not daily. Connective tissue needs recovery between loading sessions. More is not better here — it's just more.

On discomfort: some discomfort during the exercise is expected and acceptable in loading protocols. Sharp pain is not. And the practical test is what happens afterwards — if your heel is significantly worse the next morning, the load was too high. Reduce it and rebuild.

What the trial actually found

This is the section most articles skip, and it's the reason to trust the rest of this one.

Rathleff and colleagues (2015, Scandinavian Journal of Medicine & Science in Sports) randomised patients with plantar fasciitis to either high-load strength training (the protocol above) or plantar-specific stretching, and followed them for 12 months, using the Foot Function Index as the primary outcome.

At 3 months, the high-load strength training group was significantly better — a meaningful and statistically significant advantage over stretching.

At 6 and 12 months, the difference was no longer significant. Both groups had improved substantially, and they had converged.

So the honest reading is this: high-load strength training appears to get you there faster, not necessarily further. Over a year, stretching caught up.

Is a three-month head start worth having? For a condition that routinely wrecks people's lives for the better part of a year — absolutely yes. Months of your life is exactly the currency that matters here. But it is a different claim from "this is the cure that fixes what stretching can't," which is roughly how the protocol gets passed around online.

Other honest caveats: the trial was relatively small (under 50 participants), the primary outcome was self-reported, and the comparison group was stretching alone — not stretching plus load management plus everything else a good clinician would combine. One trial, well-designed, with a clear result at three months and a null result at twelve. That's the actual evidence base.

Where it fits alongside everything else

The tidiest way to think about it:

  • Stretching builds length and tolerance. Guideline-supported, low risk, and it's what the loading group was compared against — not something to drop.
  • Loading builds capacity. It's the piece the old inflammation model left out entirely.
  • Load management controls provocation — the day-to-day volume that keeps re-irritating the tissue.
  • Manual therapy and soft-tissue work appear in the JOSPT guideline as things clinicians should use, directed at joints and soft tissue of the lower limb, on the basis of low risk and consistent likely benefits.

These aren't competitors. The trial pitted two of them against each other because that's how trials work, not because you have to pick.

Realistic expectations

It takes months. The trial's primary endpoint was at three months, and that's the fast result. Anyone promising a fortnight is not describing this protocol.

Progress is not linear. Good weeks and bad weeks are normal in connective-tissue rehab. Judge by the trend across a month, not by yesterday.

Track the right thing. The most reliable early sign of improvement is usually the duration of morning pain shrinking, not its intensity. Fifteen minutes becoming five is real progress even if those five minutes still hurt.

It won't suit everyone. If single-leg heel raises are beyond you right now — because of balance, other joint problems, or pain levels — start double-legged, or work with a physio to find an appropriate entry point. Skipping to a load you can't control isn't the protocol; it's just a bad idea with a citation attached.

Why this protocol earned its reputation

Two reasons, and they're both good ones.

It is specific. Not "strengthen your feet" — a defined position, a defined tempo, a defined progression, from a published trial. In a field drowning in vague advice, specificity is itself valuable.

And it treats you as an active participant rather than a patient. Much heel-pain advice is passive: rest, ice, wear this, wait. For people who've spent months being told to stop doing things, a protocol that says here is work to do, and doing it well is how you get better changes the psychology as much as the biology.

Just hold it to what the evidence says: a faster route, not a different destination. That's still worth months of your life.

FAQ

Do I need a step? Can I do it on the floor? The step lets the heel drop below the toes, adding range. On the floor you can still do the movement, but you lose part of it. A thick book works.

How thick should the towel be? Thick enough that your toes are clearly bent upward — a firmly rolled hand towel is typically about right. If your toes are flat, you're not engaging the windlass and you're just doing calf raises.

Every other day feels too little. Can I do it daily? The protocol was every other day, and connective tissue needs the recovery. Daily loading is more likely to over-provoke than to accelerate.

Should I stop stretching if I do this? No. Stretching is guideline-supported and was the comparison arm, not a placebo. Do both.

What if it hurts? Some discomfort during the exercise is expected. Sharp pain, or a clear worsening the following morning, means reduce the load.

Sources

  • Rathleff MS et al. High-load strength training improves outcome in patients with plantar fasciitis: a randomized controlled trial with 12-month follow-up. Scandinavian Journal of Medicine & Science in Sports, 2015
  • Journal of Orthopaedic & Sports Physical Therapy — Heel Pain–Plantar Fasciitis: Revision 2023 (APTA clinical practice guideline)
  • Lemont H, Ammirati KM, Usen N. Plantar fasciitis: a degenerative process (fasciosis) without inflammation. JAPMA, 2003

This article is general education, not medical advice. Before beginning a loading programme for a painful condition, consider getting an assessment from a qualified clinician — particularly if your symptoms don't follow the classic pattern.