Aging causes motor function deterioration in the elderly population, which in turn can cause weakness in the muscles associated with swallowing. Swallowing-related problems in elderly individuals can be prevented or their symptoms can be improved with strengthening exercises for the muscles involved in swallowing. The existing strengthening exercises for the suprahyoid muscle have their limitations. Therefore, it is necessary to find another exercise that can be performed by individuals whose personal characteristics make it difficult for them to perform the existing exercises. In this study, we investigated the changes in suprahyoid muscle activation, tongue strength, and thickness of the suprahyoid muscle after 8 weeks of the head extension swallowing exercise (HESE). A total of 23 healthy elderly individuals participated in an 8-week exercise program (20 min/session, 2 times/week for 8 weeks). Suprahyoid muscle activation during effortful swallowing and the effortful-normal ratio were significantly increased at 8 weeks compared to the baseline values (p = 0.002, and 0.033, respectively). Tongue tip pressure, tongue base pressure, normal swallowing pressure, effortful swallowing pressure, and tongue tip endurance were significantly increased at 8 weeks compared with baseline (p = 0.014, 0.004, 0.046, 0.009, and 0.004, respectively). The thickness of the digastric muscle and that of the mylohyoid muscle were significantly increased at 8 weeks compared with baseline (p = 0.000 and 0.004, respectively). This study showed that HESE can be a good option for improving the suprahyoid muscle and tongue strength in the elderly population. Additionally, this exercise does not require any additional equipment and has the advantage of being able to be performed anytime and anywhere. A variety of exercise options tailored according to individual characteristics may be helpful in choosing the most appropriate exercise.