# High-intensity interval training improves cardiovascular and physical health in patients with rheumatoid arthritis: a multicentre randomised controlled trial

PMID: 39179363
Journal: British Journal of Sports Medicine
Published: 2024
Authors: Bilberg A, Mannerkorpi K, Borjesson M, Svedlund S, Sivertsson J, Klingberg E, Bjersing J

## Question

Does supervised HIIT plus strength exercise improve cardiovascular health, physical fitness, and overall health in patients with rheumatoid arthritis without worsening pain or disease activity?

## Summary

In 87 adults with well-controlled rheumatoid arthritis, 12 weeks of supervised cycling HIIT plus strength exercise improved VO2max, oxygen pulse, waist circumference, strength, and overall health compared with advice to do moderate activity. Pain and disease activity did not worsen, though some participants needed exercise modifications for symptoms.

## Population

- 87 adults with rheumatoid arthritis randomized to HIIT plus strength exercise or active control.
- Sample size: 87
- Age: 20-60 years
- Sex: 86% female
- Fitness level: Not regularly doing high-intensity cardiorespiratory exercise
- Health status: RA with DAS28 <5.1 and stable antirheumatic medication

## Methodology

- Assessor-blinded multicentre randomized controlled trial
- 12 weeks
- Physiotherapy facilities at hospitals plus one weekly self-administered aerobic session
- Randomized and controlled study design.

## Protocol

- HIIT plus strength exercise.
- Modality: Cycle ergometer and resistance training.
- Work intervals: 4 min.
- Recovery: 3 min active recovery at 70% HRmax.
- Sets or repetitions: 4 intervals; 8 strength exercises for 2-3 sets of 8-10 reps later phase.
- Intensity: 90-95% HRmax intervals; strength progressed to 70-80% 1RM.
- Session duration: 38 min HIIT plus 20 min strength.
- Frequency: 2 supervised sessions/week plus 1 self-administered aerobic session/week.
- Program length: 12 weeks.
- Progression: HIIT target reached over first 2 weeks; strength load increased across weeks 1-12.
- Moderate physical activity advice and home exercise.
- Modality: Self-managed moderate activity and home strengthening/balance exercises.
- Sets or repetitions: Five home exercises.
- Intensity: Moderate intensity, at least 150 min/week encouraged.
- Frequency: Self-managed.
- Program length: 12 weeks.

## Outcomes

### VO2max
Status: improved
Intervention improved VO2max versus control.

Between-group change 3.71 mL/kg/min, 95% CI 2.16 to 5.25, p<0.0001.

### Strength
Status: improved
Grip strength and sit-to-stand favored intervention.

Grip +28.5 N, p=0.021; 1-minute STS +5.0 reps, p<0.001.

### Disease activity
Status: no clear change
Pain and disease activity did not worsen compared with control.

DAS28 difference -0.25, 95% CI -0.60 to 0.10; pain -4.0, 95% CI -13.07 to 5.06.

### Adverse events
Status: mixed
Some symptom events required modifications, but participants generally tolerated the program.

One irregular heart-rate event; four temporary musculoskeletal pain cases; one persistent pain case completed without strength exercise.

## Practical Insights

- Clinical HIIT protocols need explicit screening, symptom thresholds, and modification pathways.
- 4 x 4 cycling HIIT can be feasible in well-controlled RA when supervised.
- Strength training contributed to benefits, so the result should not be attributed to HIIT alone.

## Limitations

- Mostly female sample and few men.
- Well-controlled RA only.
- Control group activity was not objectively reported.
- Combined HIIT plus strength intervention.
- Hospital supervision limits direct consumer translation.

## Safety And Adherence

- One intervention participant experienced irregular heart rate during supervised HIIT and completed at moderate intensity after cardiology evaluation.
- Four participants had temporarily increased musculoskeletal pain during strength exercise.
- One participant completed the intervention without strength exercise after persistent musculoskeletal pain.
- Temporary workload modification was used for pain >5/10 or pain lasting >24 hours.

## Original Sources

- [PubMed](https://pubmed.ncbi.nlm.nih.gov/39179363/) (pubmed)
- [DOI](https://doi.org/10.1136/bjsports-2023-107595) (doi)
- [PMC full text](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11672065/) (full text)

## Agent Guidance

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