The effect of exercise training on restraint ulcers in rats

The effect of chronic treadmill running on susceptibility to restraint-cold-induced ulcers was studied in two strains of rats: Long-Evans and Sprague-Dawley. Runners were progressively trained for 8 weeks, reaching a rate of 1 mph for 1 hr daily, 5 days per week after the 4th week. Walkers were exposed to the treadmill environment 3 days per week (0.2 mph for 10 min). Sedentary groups remained in their home cages. After 8 weeks the rats were starved for 24 hrs, immobilized in restraint cages and placed in the refrigerator (5° C) for 4 hrs. Animals were then sacrificed and their stomachs examined for ulcerative lesions. No significant differences in number of ulcers or ulcer indexes per stomach were found between groups within each rat strain or between strains. These results suggest that treadmill running provides no protection against gastric ulceration induced by restraint-cold stress. The complex variables involved in ulcer research are discussed and suggestions presented for future work on the anti-ulcer effect of exercise.Supported in part by the University of Nebraska Research Council Summer Fellowship.