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Personalised Exercise for axSpA: What Two Studies Show

Two studies from Ghent University Hospital did something unusual for exercise research in axial spondyloarthritis: they measured first, then trained. The gap they found — and closed — says something important about how movement should be prescribed. Every guideline for axial spondyloarthritis (axSpA) says the same thing: exercise. It’s safe, it’s effective, and it belongs alongside pharmacological treatment. What almost none of them say is which exercise, at what intensity, for how long. That gap isn’t an oversight. It’s a measurement problem. You can’t write a dose without a baseline, and for axSpA the baseline picture has been incomplete, strength, spinal mobility, and cardiorespiratory fitness are typically studied one at a time, in different cohorts, with different tools. A research team at Ghent University Hospital set out to assess all three at once, in the same patients. The result was two papers: one that maps the deficit, and one that closes it.

Paper one: where the losses actually are

Published in The Journal of Rheumatology in 2024, the first study was cross-sectional. 58 people with axSpA — mean age 40.8 years, half male, average symptom duration just over ten years — went through maximal cervical and trunk mobility and isometric strength testing in every plane of movement, using DAVID Back Concept devices. Twenty-five of them also completed a maximal cardiopulmonary bicycle exercise test. Everything was benchmarked against healthy reference data.

Both strength and mobility came back significantly below reference. But the more useful finding was the ranking between them: strength was more affected than mobility.

That runs against a lot of clinical intuition. Stiffness is the symptom patients describe and the thing clinicians can see, so mobility tends to dominate both the conversation and the exercise plan. The objective data suggested the larger deficit was sitting somewhere less visible.

The pattern also split by disease subtype in an instructive way. Strength deficits were broadly similar between patients with and without radiographic involvement — with trunk extension as the exception. Mobility deficits were markedly worse in the radiographic group across cervical extension and rotation and trunk extension and rotation, and this held regardless of how long people had been symptomatic.

On the cardiorespiratory side, the impairment was mainly metabolic rather than mechanical — the aerobic engine, not the pump. The authors’ conclusion was direct: personalised exercise programmes for axSpA need a cardiopulmonary component sitting alongside strength and mobility work.

The underlying point

Three capacities, three different deficits, distributed differently in every patient. An off-the-shelf programme can only get that right by accident.

Paper two: what happens when you act on it

The follow-up, published in RMD Open in 2025, tested whether that baseline data could be turned into a better programme.

Thirty participants (14 men, 16 women, mean age 42) were assessed exactly as before — cardiopulmonary exercise testing plus strength and mobility testing on DBC devices — and their individual deficits were calculated. Those numbers then set the prescription.

The programme ran eight weeks, two sessions per week. Each session opened with cardiorespiratory training set against the individual’s ventilatory threshold, with heart rate monitored throughout, then moved to resistance and mobility work on the DBC devices. Load was tailored to each person’s one-repetition maximum and range of motion at baseline. Two participants were lost to follow-up.

  • +14.1%Trunk strength (p<0.001)
  • +14.9%Trunk mobility (p<0.001)
  • 3.5→2.9BASDAI disease activity (p=0.021)

The cardiorespiratory results moved in parallel: significant improvements in oxygen pulse, ventilatory efficiency, anaerobic threshold, and mechanical efficiency. Chest expansion — a marker that matters a great deal in this population — rose from 4.5 cm to 5.0 cm. Sixteen sessions. Measurable change in all three capacities at once, plus a drop in how active patients reported their disease to be.

What the study honestly doesn’t show

Two results did not reach significance, and they’re worth stating plainly. BASMI, the metrology index, landed at p=0.053 — borderline. BASFI, which captures self-reported functional ability, didn’t shift at all. That last one is a real limitation. Improving a patient’s measured capacity and improving their experience of daily function are different achievements, and eight weeks appears to have delivered the first without yet delivering the second. Whether a longer programme closes that gap is an open question.

Methodological note

The intervention study was a single-arm prospective trial with 30 participants and no control group. Without one, improvement can’t be cleanly separated from natural fluctuation, testing familiarity, or the attention effect of a supervised programme. The findings are encouraging and consistent — they aren’t yet the randomised evidence that would settle the question.

Why this matters beyond axSpA

What makes these two papers useful together isn’t any single number. It’s the sequence. The first study established that deficits in this population are uneven and not reliably predictable from the clinical picture — the visible problem was not the biggest problem. The second established that when you measure those deficits and let them set the dose, meaningful change follows in a short window.

That’s the logic the DAVID Back Concept was built around: objective assessment isn’t a separate diagnostic step that precedes training, it is the training prescription. Range of motion and one-repetition maximum aren’t just outcome measures to report at the end — they’re the inputs that determine what happens in session one.

Both studies used DAVID Back devices as measurement instruments first and training equipment second. For a condition where the guidelines say “exercise” and stop short of saying how, that dual role is the part worth paying attention to.

  • Assess all three capacities. Strength, mobility, and cardiorespiratory fitness fail independently. Testing one tells you little about the others.
  • Don’t assume mobility is the priority. In this cohort, strength was the larger deficit despite stiffness being the dominant symptom.
  • Include the cardiopulmonary component. The impairment was metabolic, and it responded to threshold-based training.
  • Let the baseline set the dose. Individual 1RM and ROM, not a standard protocol.

References

De Mits S, Willems TM, Calders P, Danneels L, Varkas G, Van den Bosch F, Elewaut D, Carron P. Maximal Exercise Tolerance, Objective Trunk Strength, and Mobility Measurements in Axial Spondyloarthritis. The Journal of Rheumatology, June 2024. PMID: 38490674. DOI: 10.3899/jrheum.2023-1046 · PubMed

De Mits S, Willems T, Calders P, Danneels L, Varkas G, Van den Bosch F, Elewaut D, Carron P. Patient-tailored training programme on cardiorespiratory fitness, trunk strength and mobility leads to significantly better outcomes in individuals with axial spondyloarthritis. RMD Open, December 2025. PMID: 41475840. DOI: 10.1136/rmdopen-2025-006039 · PubMed

These are independent academic studies conducted by researchers at Ghent University and Ghent University Hospital. This article summarises their published findings and is intended for general information — it is not a clinical claim regarding DAVID devices, nor a substitute for professional medical advice.