Abstract
PURPOSE: Maslinic acid (MA) is a component derived from a natural olive-based extract known to have pharmacological functions that include suppressing inflammation. This study examined how MA, in conjunction with whole-body vibration training (WBVT), can improve knee and muscle function in elderly women with knee osteoarthritis (OA). METHODS: The study was a double-blinded, placebo-controlled, randomized intervention study that enrolled individuals with knee pain. Participants were 26 females aged 65-85 years with knee OA. They performed WBVT and ingested either 16.7 mg of MA or a placebo daily for 20 weeks. We compared the effect of WBVT with placebo (WBVT/P) and WBVT with MA (WBVT/MA) in participants with various degrees of knee OA (Kellgren and Lawrence (K-L) grade) using the Japanese Orthopaedic Association (JOA) score and isokinetic dynamometer measurements to evaluate knee and muscle function with two-way ANOVA. RESULTS: Based on the results of two-way ANOVA analysis of muscle function measurements, there was significant interaction (time × group) (P = 0.03) in the "isokinetic extension peak torque" domain for severe OA (K-L grade ≥ 3). The simple main effect of time in the WBVT/MA group (P = 0.04) contributed to this interaction. The JOA score for WBVT/MA supported the main effect of group as having a significant correlation in the "pain on walking" (P = 0.04) and "range of motion" (P < 0.01) domains. Participants with severe knee OA in the WBVT/MA group improved in these domains, whereas the WBVT/P group had few positive results. CONCLUSIONS: Participants with severe OA who ingested MA in conjunction with WBVT improved their knee and muscle function. This study suggests that ingesting the anti-inflammatory supplement MA while participating in WBVT, elderly women can reduce knee OA and improve their knee muscle strength.