Abstract: Background　Critically ill patients often experience enteral nutrition intolerance due to delayed gastric emptying, which affects clinical outcomes. Early mobilization helps improve gastric emptying; however, the effects of different mobilization methods on gastric emptying have not been reported. Objective　To compare the effects of different early mobilization methods on gastric emptying function, enteral nutrition tolerance, and nutritional indicators in critically ill patients. Methods　Patients receiving enteral nutrition in the Department of Critical Care Medicine, the First Medical Center of PLA General Hospital from January to October 2025 were selected and divided into an immobilization group, an upper limb exercise group, a ROM (Range of Motion) training group, and an in-bed cycling group based on their mobilization methods. Gastric emptying rate was monitored using gastric ultrasonography before daily feeding (7:30) and after daily activity (18:00) for 7 consecutive days. The incidence of enteral nutrition intolerance (abdominal distension, diarrhea, nausea, vomiting, and gastric retention) was recorded, and nutrition-related indicators (serum albumin, total protein, and hemoglobin) were monitored. Results　A total of 118 patients were included, with comparable baseline characteristics among the immobilization (n=39), upper limb exercise (n=18), ROM training (n=29), and in-bed cycling (n=32) groups. The mixed-effects model showed that the gastric emptying rate significantly improved over time (P＜0.001), with statistically significant overall inter-group difference (P＜0.001) and significant time-group interaction (P＜0.001), indicating different time-dependent trends among the mobilization groups. From day 3 of enteral nutrition, the gastric emptying rates in the ROM training (92.98%±3.51%) and in-bed cycling (92.73%±3.32%) groups were higher than those in the upper limb exercise group (90.56%±3.43%) (P＜0.05), and the rates in the mobilization groups were significantly higher than that in the immobilization group (88.25%±3.73%) (P＜0.05). The incidences of abdominal distension (3.1% vs 25.6%) and gastric retention (3.1% vs 25.6%) in the in-bed cycling group were significantly lower than those in the immobilization group (P＜0.05); the incidence of abdominal distension in the ROM training group was also significantly reduced (3.4% vs 25.6%, P＜0.05); the incidence of diarrhea in the upper limb exercise group was lower (0 vs 23.1%, P=0.056). The mixed-effects model revealed that nutritional indicators significantly changed over time (P＜0.001) with significant time-group interaction (P＜0.001). From day 3, hemoglobin levels, subsequently albumin and total protein levels in the mobilization groups were higher than those in the immobilization group (P＜ 0.05), with more significant improvements observed in the ROM training and in-bed cycling groups (P＜0.05). Conclusion　For hemodynamically stable ICU patients, early initiation of in-bed cycling or ROM training is more effective than immobilization o upper limb exercise in improving gastric emptying, enhancing enteral nutrition tolerance, and promoting nutritional recovery.