Bartlett DB, et al. - Authors ascertained if 10 weeks of a walking-based high-intensity interval training (HIIT) program would be related to health improvements as measured by disease activity and aerobic fitness in older adults with rheumatoid arthritis. They also evaluated if HIIT was associated with an improved immune function, specifically antimicrobial/bacterial functions of neutrophils and monocytes. This study suggested for the first time an association of a high-intensity interval walking protocol with reduced disease activity, improved cardiovascular fitness, and improved innate immune functions, indicative of reduced infection risk and inflammatory potential in older adults with stable RA. These patients demonstrated a good tolerance towards the exercise program.