Effect of progressive head extension swallowing exercise on lingual strength in the elderly: A randomized controlled trial

Lingual strengthening training can improve the swallowing function in older adults, but the optimal method is unclear. We investigated the effects of a new progressive resistance exercise in the elderly by comparing with a conventional isometric tongue strengthening exercise. Twentynine participants were divided into two groups randomly. One group performed forceful swallow of 2 mL of water every 10 s for 20 min, and a total of 120 swallowing tasks per session at 80% angle of maximum head extension. The other group performed five repetitions in 24 sets with a 30 s rest, and the target level was settled at 80% of one repetition maximum using the Iowa Oral Performance Instrument (IOPI). A total of 12 sessions were carried out by both groups over a 4-week period. Blinded measurements (for maximum lingual isometric pressure and peak pressure during swallowing) were obtained using IOPI before exercise and at four weeks in both groups. After four weeks, both groups showed a significant improvement in lingual strength involving both isometric and swallowing tasks. However, there was no significant difference between the groups in strength increase involving both tasks. Regardless of the manner, tongue-strengthening exercises substantially improved lingual pressure in the elderly with equal effect.