The effects of exercise on early rheumatoid arthritis: from physiological mechanisms to exercise interventions

Rheumatoid arthritis (RA) is the most common inflammatory condition and associates with movement limitations, low cardiorespiratory fitness and impaired physical and psychological health. Exercise is known to improve physical and psychological health in people with RA without affecting disease activity. However, most data on exercise in RA comes from people with established disease (i.e. more than two years since diagnosis), yet disease management guidelines recommend exercise in the early stages of the disease. Thus, there is an urgent need to examine the impact of exercise in early RA. Despite the well-established benefits of exercise in RA, participation in any form of physical activity (PA) is very low amongst this population. Pain and fear of disease aggravation are commonly cited barriers to PA participation. In recent years, the coronavirus pandemic and the associated lockdowns added further barriers to PA engagement. This thesis sought to investigate the utility of exercise among people with early RA and examine the impact of the COVID-19 lockdown on PA participation in people with RA.

Chapter 3 systematically reviewed the acute effects of exercise on pain symptoms, clinical inflammatory markers and inflammatory cytokines in RA. The findings suggest acute bouts of exercise did not exacerbate pain symptoms in people with RA, and post-exercise responses for pain, clinical inflammatory markers and inflammatory cytokines appear similar between people with and without RA. 

In Chapter 4, the feasibility of varied exercise modes and intensities for people with early RA was investigated. Participants completed the exercise trials in full and enjoyed all exercises. Also, none of the exercise modes or intensities increased pain or fatigue and no adverse effects were observed in blood biomarkers associated with inflammation or joint health.

Chapters 5 and 6 sought to understand how the COVID-19 lockdown impacted PA and associated health aspects among people with RA. PA levels reduced more in people with than those without RA. Novel findings are presented on PA participation in people with RA, as it appears PA remained low throughout lockdown, with minimal improvement even after most restrictions were lifted.  

In conclusion, this thesis has showed that acute exercise does not aggravate disease activity and the novel data may indicate the utility of exercise among people with early RA. Furthermore, people with early RA tolerate and enjoy a variety of exercise modes and intensities. This thesis also suggests that PA participation in people with RA has decreased as a result of the pandemic. These findings are important, particularly in the post-COVID era, where PA interventions specific to people with RA are required to address the significant reductions in their PA levels. These findings can hopefully better educate healthcare professionals and people with RA, as well as manage patient fears and expectations around exercise. Future studies should look to explore these themes as they represent important areas of investigation in RA.