Aerobic exercise improves gastrointestinal motility in psychiatric inpatients

AIM:To evaluate the benefit of aerobic exercise on colonic transit time(CTT)for psychiatric inpatients in a closed ward.METHODS:Sixty consecutive adult inpatients of the Somang Hospital Psychiatry Unit(Eumsung-gun,South Korea),without CTT-related diseases or drug therapies,were recruited for study from March to June of 2012.Upon enrollment,the patients were randomly assigned to partake in a 12-wk instructor-led group aerobic exercise program(exercise group;n=30)or to maintain their ordinary daily activities(control group;n=30).The exercise program was structured as 10 min warm-up(stretching),40 min exercise,and 10 min cool-down(stretching)for three days each week.The exercise sessions consisted of walking only in week one and aerobics from weeks two to 12,with increasing intensity(50%heart rate reserve(HRR)for weeks one to four,60%HRR for weeks five to eight,and 70%HRR for weeks nine to 12).CTT was measured before(baseline)and after(week 12)the exercise program,in duplicate(on days four and seven),using abdominal radiography and the multiple radio-opaque marker technique.Changes in the exercising patients’CTT and weight-,cardiovascular-and fitness-related parameters were statistically assessed.RESULTS:The study dropout rate was 30.0%,with 23patients in the exercise group and 19 patients in the control group completing the study.At week 12,the exercise group showed decreases in body weight(mean±SE)baseline:69.4±2.8 vs study-end:67.6±2.7;P<0.635)and body mass index(BMI)(25.2±1.1 vs24.9±0.8;P<0.810),but the extent of change was not significantly different from that experienced by the control group(body weight:68.8±4.0 vs 68.8±3.9;BMI:24.3±1.1 vs 24.4±1.2).However,the exercise group showed significant improvements in leg muscle strength(baseline:41.7±4.3 vs study-end:64.1±5.0;P<0.001),cardio-respiratory endurance(120.5±4.5vs 105.4±2.8;P<0.004),and leg muscle elasticity and power output(21.5±2.6 vs 30.6±2.8;P<0.001).The exercise group showed an exercise-induced reduction in total CTT(baseline:54.2±8.0 vs 30.3±6.1),which was significantly different from that experienced by the control group over the 12-wk period(48.6±9.3vs 48.3±12.3;P=0.027);however,the exercise-induced decreases in CTT involving the three colonic segments examined(right,left and recto-sigmoid)showed no significant differences from the control group.CONCLUSION:A 12-wk aerobic exercise program can benefit psychiatric inpatients by increasing intestinal motility,possibly decreasing