Effect of Masticatory Movement Using Gum on Walking and Cycling: A Randomized Crossover Design

PURPOSE Gum chewing stimulates the sympathetic nervous system and increases energy consumption. However, the effect of mastication on physical activity remains unclear. This study aimed to investigate the effect of gum masticatory movement on physiological markers related to walking and muscle activation during cycling in different patient groups. METHODS Using a randomized crossover design, 25 participants participated in walking trials with a 1-week washout; the trials included chewing gum (GUM), taking a candy with the same ingredients as the gum (CAN), and no ingestion (CON). Energy expenditure (EE), metabolic equivalent (MET), oxygen consumption (VO2), and heart rate were measured using a portable metabolic device. The walking distance was also calculated. In the cycling experiment, the other 19 participants randomly completed 7 minutes of the three trials (GUM, CAN, CON) with a 15-minute break. The mean cycling period (MCP), cycle number (CN), coefficient of variation of the cycling period (CV), and integrated electromyography (iEMG) results were measured using the Delsys Trigno™ Wireless EMG System. RESULTS The walking distance was significantly higher in the GUM group than in the CAN and CON groups by an average of 78 m (7.4%, p<.05). Comparing the GUM and CON groups, EE, METs, and VO2 demonstrated a partially significant increase after 15 minutes. In the cycling experiment, there were no significant differences in the effects of the trials on cycling performance (MCP, CN, CV). However, significant differences were observed in the GUM group for the iEMG results. CONCLUSIONS Our study results suggest that gum chewing improves physical performance, such as walking distance, and improves energy metabolism, such as EE and METs. Additionally, it can influence the improvement in the lower limb muscle activity during cycling.