Effects of Press Needle Intervention on Knee Flexion and Extension Movements: A Randomized Trial

Abstract
Objective: Knee flexion exercise is a type of exercise therapy for improving knee-joint muscle strength. Among the knee extensors, the vastus medialis muscle is less active and prone to disuse atrophy. The effects of press needle acupuncture include vasodilation, which may affect blood flow in the vastus medialis. This study examined the effects of exercise stimulation + press needle stimulation on muscle blood flow. Materials and Methods: Conducted in Teikyo Heisei University, Tokyo, Japan, this randomized controlled trial involved 30 healthy adults in 3 groups (10 who did not receive stimulation, 10 who received exercise stimulation only, and 10 who received press needle stimulation + exercise stimulation). The stimulations were applied once per week, for 3 weeks. After resting for 10 minutes, the nonstimulated group rested for 2 additional minutes, and the other 2 groups performed knee flexion and extension exercises considered to be “very very hard on the Borg rating.” After this activity, the 2 stimulation groups rested for 10 minutes. Press needle stimulation was applied on the vastus medialis muscles of both thighs in the combination stimulation group. Results: The combination group had a smaller decrease in muscle tissue oxygen saturation and an increase in total hemoglobin, compared to the exercise only stimulation group. Conclusions: Press needle stimulation during exercise may dilate muscle blood vessels. Future studies should examine the effectiveness of this stimulation for age-specific and knee diseases.