We previously reported on the positive effects of strength training performed once every other week for 3 months. The present study aimed to examine whether physical function of middle-aged and elderly people improved when attending a muscle strength improvement class once every two months. The study subjects were 64 middle-aged and elderly people (28 men, 36 women; mean age, 71.3±3.8 years). The class consisted of four types of strength training and stretching and was held once every two months for one year. In addition, training other than the strength training was carried out for each person about 3 days a week. The subjects underwent the 30-second chair-stand (CS-30) test, one-leg standing time test with eyes open, and seated forward flexion test, and we evaluated their physical function based on age (60 and 70-year-olds) and sex over one year. CS-30 test results increased significantly in all groups (P<0.001). However, results of the one-leg standing time test with eyes open decreased significantly in all subjects in their 70s (P<0.01), and similar changes were seen the women (P<0.05). Seated forward flexion test results increased significantly only in the subjects in their 60s (P<0.05). The present evaluation showed that training guidance provided once every two months improved or maintained lower limb muscle strength and flexibility. However, it suggested that balance ability decreased due to age-related changes even if guidance is given at this frequency.