Impact of Stress on Stomach Digestion and Acid Production: The Role of Physical Activity in Modulation

Abstract

Stress negatively affects gastrointestinal function by increasing gastric acid secretion, impairing digestive enzyme activity, and slowing gastric motility, potentially leading to gastritis, ulcers, and indigestion. Physical activity has been proposed as a non-pharmacological intervention to mitigate stress-induced gastrointestinal disturbances. This study aimed to investigate the effects of stress on gastric acid secretion and digestive efficiency and examine the role of moderate physical activity in modulating these effects. Thirty healthy adults were randomly assigned to a sedentary-stress group or an exercise-stress group. Gastric acid levels, pepsin activity, and salivary cortisol were measured before and after a standardized stress task. Results indicated that stress increased gastric acid by 25% in sedentary individuals compared to 10% in the exercise group, while pepsin activity was better preserved in physically active participants. Moderate physical activity significantly reduced stress-induced gastric alterations, suggesting exercise as a protective factor against stress-related digestive disorders.

Keywords:  Stress, Gastric acid secretion, Digestion, Physical activity, Cortisol, Peptic ulcers