High-intensity interval training (HIIT) reduces inflammation associated with rheumatoid arthritis (RA) and improves cardiorespiratory fitness among patients with RA, Duke clinicians and researchers reported during the American College of Rheumatology sessions in November 2019.

While the research continues, with a focus on identifying the mechanism that reduces systemic inflammation, the research team emphasizes the value of the fitness findings as significant clinical guidance.

Patients with RA are at greater risk for cardiometabolic disease, disability, and early death, says Brian Andonian, MD, a third-year Duke rheumatology fellow who directed the study with exercise immunologist David Bartlett, PhD, cardiologist William E. Kraus, MD, and rheumatologist Kim H. Huffman, MD, PhD. Recent studies suggest that the long-term cardiometabolic risk for patients with RA may be at least as great or greater than those patients with Type 2 Diabetes Mellitus, Andonian says.

“Promoting movement and fitness in this patient group should be a priority,” says Andonian. “We believe this research can lead to further findings that will help us understand what drugs will work effectively with exercise for patients with RA.”

The research, which involved patients recruited from Duke rheumatology clinics, offers two key conclusions, Andonian says:

• Cardiorespiratory fitness improvements in RA were associated with muscle amino acid reductions.
• Systemic inflammation improvements in RA were associated with greater muscle concentrations of multiple components of oxidative metabolic machinery.

The researchers proposed that exercise training shifts metabolic substrates to skeletal muscle (for enhanced protein synthesis and fat oxidation) and away from circulating immune cells, resulting in reductions in systemic inflammation.

Exercise for patients with RA is not recommended often enough despite awareness among researchers of the significance of the relationship between exercise and disease improvement, Andonian says.

“Even though it’s clear that exercise is helpful for patients with RA, this is not fully understood or embraced by the rheumatology community,” Andonian says. “Some practitioners fear that exercise makes the symptoms worse for these patients. We should be talking to patients about becoming more physically active.”

HIIT requires less time than traditional cardiovascular training. Patients alternate between one minute of high-intensity effort—based on individual ability and fitness—and another minute at a lower level. Patients repeat this cycle of high intensity and low intensity effort 10 times.