Concentrations of thyroid and their thyrotrophic hormone can be suitable index for exercise pressure. But the effects of sport on thyroid hormones in not only it have been less attention but also are not clear well. 16 young taekwondo athletes with average 22.7±2.02 years, 176.5 ± 3.82 cm height and 71.29±8.73 kg weight was selected purposeful and were participated in one session taekwondo exercise for our hour with %70 intensity maximum heart rate (HR max). Before and immediately after and one hour after exercising blood sampling were taken and was measured the concentration of thyroid stimulating hormone (TSH), thyroxin (T4), and triiodothyronine (T3). To examine changes variance ANOVA test were used and only in T4 hormone, significant difference was observed, that the difference between before and one hour after exercise was significant (P<0.05). In fact these three hormones increased of exercising which of course about TSH was less decreased till one hour after exercise. In T3 and T4 minor and nonsignificant increasing was observed. With pay attention to increased TSH, T4 and T3 hormones which is followed by exercise in present research, it seems to training taekwondo with intensity and duration, doesn’t enter double pressure in the body, and it can be use for improvement health and cardio-respiratory fitness for all people.
