Gastric emptying rates of radiolabeled beef stew meals were measured in 10 healthy, young (median age = 27 years) male subjects on each of three randomly chosen study days. The subjects either (1) stood at rest, (2) walked on an exercise treadmill at 3.2 km/hr, or (3) at 6.4 km/hr during the study while gastric emptying was being monitored by externally positioned gamma cameras. Compared to the standing at rest study, exercise significantly increased gastric emptying (at rest emptying half-time (t1/2) = 72.6 +/- 7.6 (SEM) min; 3.2 km/hr t1/2 = 44.5 +/- 3.9 min, P = 0.0051; 6.4 km/hr t1/2 = 32.9 +/- 1.9 min, P = 0.0051). The 6.4 km/hr emptying time was significantly (P = 0.0249) faster than the 3.2 km/hr emptying time. Thus, the amount of exercise is a physiological factor that alters solid meal gastric emptying rates.