Effects of Physical Exercises Alone on the Functional Capacity of Individuals with Obesity and Knee Osteoarthritis: A Systematic Review

SIMPLE SUMMARY: Osteoarthritis is a degenerative joint disease that affects millions of people around the world. Knee osteoarthritis is one of the causes of more significant functional disability among people with it. Currently, obesity is identified as one of the main risk factors for the onset of the disease due to excess load on the joints of the lower limbs, especially the knees. The association of measures, such as weight reduction through diets and exercise, can alleviate symptoms and increase the physical condition of people affected by these clinical conditions. However, many individuals with obesity have difficulty adhering to diet programs and need to improve in order to perform their functional activities. The aim of this systematic review was to evaluate the results of several physical exercise programs conducted without the association of diet, demonstrating the improvement of the functional capacity of individuals with these concomitant clinical conditions, presenting another proposal to reduce the symptoms of the disease in this population. ABSTRACT: The association between obesity and knee osteoarthritis (KOA) is reported in the literature. The inflammatory factors described in obesity associated with mechanical overload on the knee joint lead to KOA development and reduced functional capacity in these individuals. Most physical exercise (PE) protocols associate a diet program to improve the functional capacity of individuals with concomitant KOA and obesity. There is a lack of published protocols performing PE alone, which would be without an associated diet program in individuals with both clinical conditions. In this systematic review, the authors summarize the effects of the application of PE alone, describing each protocol and reporting the improvement in the function of people with these clinical conditions. This investigation was conducted according to the PRISMA guidelines and registered in PROSPERO. Five databases (MEDLINE/PubMed, PEDro, Scopus, CINAHL and Web of Science) were used up to July 2022 and ten studies, including 534 participants, met the inclusion criteria. The PEDro scale, Cochrane collaborations and ROBINS-I tools were used to evaluate the methodological quality and risk of bias. It was concluded that PE performed alone seems to provide an improvement in the functional capacity of these individuals even without an associated diet plan in the condition of obesity.