# Changes of inflammation in patients with psoriatic arthritis after high intensity interval training assessed by ultrasound and MRI, a randomized controlled trial

PMID: 37726677
Journal: BMC Musculoskeletal Disorders
Published: 2023 Sep 19
Authors: Thomsen RS, Nilsen TIL, Haugeberg G, Sitter B, Kavanaugh A, Pedersen SJ, Hoff M

## 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.

## Population

- 67 patients with psoriatic arthritis randomized to HIIT or usual activity control.
- Sample size: 67
- Age: HIIT mean 50.7 years; control mean 45.6 years
- Sex: Mixed; about two-thirds female
- Health status: PsA with low to moderate disease activity

## Methodology

- Randomized controlled trial with parallel groups
- 11 weeks with 3-month imaging follow-up
- Supervised stationary-bicycle HIIT plus one self-guided weekly HIIT session
- Randomized and controlled study design.

## Protocol

- Stationary-bike HIIT for PsA.
- Modality: Stationary cycling.
- Work intervals: 4 min.
- Recovery: 3 min at 70% HRmax.
- Sets or repetitions: 4 intervals.
- Intensity: 85-95% HRmax.
- Session duration: At least 31 min plus any cool-down not reported.
- Frequency: 3 sessions/week.
- Program length: 11 weeks.
- Usual physical exercise habits.
- Modality: No prescribed change.
- Program length: 11 weeks.

## Outcomes

### US joints
Status: no clear change
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
Status: no clear change
Power Doppler enthesis worsening was nearly identical between groups.

32% vs 31%, OR 1.05 (95% CI 0.34 to 3.22).

### MRI BME
Status: no clear change
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).

## Practical 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 And Adherence

- 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.

## Original Sources

- [PubMed](https://pubmed.ncbi.nlm.nih.gov/37726677/) (pubmed)
- [DOI](https://doi.org/10.1186/s12891-023-06871-3) (doi)
- [PMC full text](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10508016/) (full text)

## Agent Guidance

Preserve the paper-level scope of this note. Do not generalize beyond the population, protocol, measured outcomes, and limitations above.