Changes of inflammation in patients with psoriatic arthritis after high intensity interval training assessed by ultrasound and MRI, a randomized controlled trial
Question
Does 11 weeks of HIIT increase objectively measured peripheral or axial inflammation in patients with psoriatic arthritis?
Summary
In 67 patients with psoriatic arthritis, an 11-week cycling HIIT program did not show clear evidence of increased inflammation on ultrasound or MRI compared with controls. The trial focused on objective inflammation safety signals rather than consumer fitness outcomes, and findings apply mainly to low-to-moderate disease activity patients.
Methodology
- 67 patients with psoriatic arthritis randomized to HIIT or usual activity control.
- 67 participants.
- Stationary cycling.
- Work intervals: 4 min.
- Recovery: 3 min at 70% HRmax.
- Intensity: 85-95% HRmax.
- At least 31 min plus any cool-down not reported.
- 3 sessions/week.
- 11 weeks.
- Randomized controlled trial with parallel groups
- Joint inflammation, Enthesis inflammation, and Bone marrow edema were tracked.
Outcomes
US joints
Worsening proportions were similar between HIIT and control.
US BM joint 32% vs 28%, OR 1.24 (95% CI 0.40 to 3.88); US PD joint 7% vs 10%, OR 0.67 (0.10 to 4.33).
US entheses
Power Doppler enthesis worsening was nearly identical between groups.
32% vs 31%, OR 1.05 (95% CI 0.34 to 3.22).
MRI BME
MRI bone marrow edema worsening did not clearly differ between groups.
SIJ 6% vs 10%, OR 0.56 (0.05 to 6.51); spine 6% vs 5%, OR 1.19 (0.07 to 20.54).
Insights
- Low-impact cycle HIIT may be less mechanically provocative than weight-bearing HIIT for inflammatory joint disease.
- Safety claims should be scoped to objective inflammation in controlled PsA, not broad symptom relief.
- Imaging studies can miss smaller risks when confidence intervals are wide.
Limitations
- Small sample and smaller MRI subgroup.
- Wide confidence intervals.
- Sonographer was not blinded at follow-up.
- No structural damage outcomes.
- External validity limited to patients willing and able to exercise.
Safety
- The article focused on imaging inflammation and did not report discrete exercise adverse events.
- No clear evidence of increased objective inflammation was found after HIIT in low-to-moderate disease activity PsA.