Cardioprotective effect of high intensity interval training and nitric oxide metabolites (NO2−,NO3−)

Background: the aim of this study was to investigate the effects of high-intensity interval training (hiit) on nitric oxide metabolites (no2−,no3−) and myocardial infarct size after ischemia/reperfusion (i/r) injury in healthy male rats. methods: a total of 44 wistar rats were randomly divided into 4 groups including hiit (n=8),hiit + ir protocol (n=14),control (n=8),and control + ir (n=14). each training session of hiit consisted of 1 hour of exercise in three stages: 6-minute running at 50-60% vo2max for warm-up; 7 intervals of 7-minute running on treadmill with a slope of 50 to 20° (4 minutes with an intensity of 80-100% vo2max and 3 minutes at 50-60% vo2max); and 5-minute run-ning at 50-60% vo2max for cool-down. the control group did not participate in any exercise program. nitric oxide (no) and its metabolites were measured by using griess reaction test. results: the results showed that eight weeks of exercise training exerted a significantly increasing effect on nitrite (8.55 μmol per liter,equivalent to 34.79%),nitrate (62.02 μmol per liter,equivalent to 149.48%),and nox (66 μmol per liter,equivalent to 98.11%) in the hiit group compared with the control group. the results showed myocardial infract size (is) was significantly smaller (23.2%,p<0.001) in the exercise training group compared with the control group. conclusion: incremental changes in no-no3−,no2− axis are one of mechanisms through which hiit program can protect the heart from i/r injury and decrease myocardial infarction. © 2015,iranian journal of public health. all rights reserved.