Abstract: Objective To observe the relationship between duration time of isometric contraction and blood pressure.Methods The blood pressure of 16 healthy young males was recorded before and after 3 sessions of push-up exercise.All subjects did the push-up and hold there for 5 s(T5),10 s(T10) and 15 s(T15),respectively.Results The systolic pressure increased no matter the isometric contraction exercise lasts for 5 s,10 s and 15 s(P<0.05) and no significant difference was found in the systolic pressures after isometric contraction in group T5,group T10 and group T15(P>0.05),and also no significant difference was found in the change of pulse systolic pressure between group T5 and group T10(P>0.05),but there was a significant difference between both group T5 and group T15,group T10 and group T15(P<0.05).Conclusion The isometric contraction exercise can increase the systolic pressure and the effect of cushion reflex on adjusting blood pressure may last 10～15 s.

Key words: isometric contraction, blood pressure, rehabilitation exercise