A total of 12 acupressure sessions , 3 / wk for 1 mo , were performed for all participants in the intervention group , as required by the acupressure application protocol , applying acupressure at the Stomach 36 ( ST-36 ) , Gallbladder 34 ( GB-34 ) , Spleen 6 ( SP-6 ) , and Kidney 1 ( K-1 ) acupuncture points with a transcutaneous electrical nerve stimulation ( TENS ) acupuncture pen ( XFT-320 acupuncture pen , Shenzhen Xunfegtong Electronics Co , Ltd , Shenzhen , China ) .