Blood Pressure and Heart Rate Responses to Sustained Static (Isometric) Contractions by Handgrip Dynamometry in Three Trimesters of Pregnancy

Abstract

Title: Blood pressure and heart rate responses to sustained static (isometric) contractions by handgrip dynamometry in three trimesters of pregnancy. Objective: To measure the blood pressure and heart rate responses at various intensities, in three trimesters of pregnancy to the sustained isometric exercises, by handgrip dynamometry and comparing the results with the controls. Materials and methods: subjects -20 healthy pregnant women, Controls -20 non-pregnant healthy women. Subjects were followed for three trimesters. Blood pressure and heart rate were evaluated with handgrip dynamometer at Rest, 20% and 30% intensities of maximum voluntary contraction and Post Exercise. Blood pressure and Heart rate were recorded with the help of Sphygmomanometer, Stethoscope, and ECG machine. Results: Blood pressure and heart rate increased more during sustained handgrip exercise in Subjects than the Controls. At rest and during static exercise blood pressure reduced in First, Second and increased in Third trimesters, compared to controls. At rest and during static exercise heart rate increased in First, Second trimesters and Third trimester displayed steady levels when compared to the controls. Maximum voluntary contraction in the Controls was higher than the Subjects. Conclusion: Sustained isometric exercise produces an increase in hemodynamics during different trimesters of pregnancy.

A comparative study of cardiovascular autonomic function tests between second trimester pregnant women and non-pregnant women

“…[9] In our study, the maximum rise in DBP during isometric handgrip exercise was significantly less in the second trimester when compared to controls. This is in accordance with many studies [4,8,[10][11][12] which have shown that there is decreased sympathetic activity more in the second trimester, which explains the decreased peripheral vascular resistance in the second trimester is by decreased sympathetic activity. [8] The reduced BP response reported could be due to an antagonistic effect of products of uteroplacental unit such as progesterone or a diminished contractile response of the blood vessels to adrenaline.…”

“…[17] In our study of HR response to deep breathing, the ratio of maximum-to-minimum RR-interval during respiratory cycles, that is, the E/I ratio of RR intervals, was found to be significantly less in the second trimester compared to controls. In accordance with our results, many studies [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21] showed HR response to deep breathing expressed as deep breathing difference (DBD), a measure of cardiac parasympathetic function was observed to be significantly lower in pregnant women when compared to control group and generally followed a decreasing trend with increase in gestation. [4] This finding was in conformity with observation of Ekholm et al who suggested a multifactorial basis for it.…”

Maternal blood pressure and heart rate response to pelvic floor muscle training during pregnancy

“…In publications on exercise science it has been shown that attempts to maximally contract other skeletal muscles with a holding period may increase blood pressure (BP) and heart rate (HR) . The increase in cardiovascular response (HR and BP) during skeletal muscle contraction is related to the amount of active muscle mass utilized during exercise and to the intensity and duration of muscle contraction .…”

“…Several studies indicate that concentric contractions promote higher increases than eccentric contractions, but lower increases than isometric contractions . Some researchers have suggested that high intensity isometric contractions of small muscle groups take more effort and thus contribute more to a rise in HR . The pelvic floor muscle contraction can be considered a dynamic contraction as it has been demonstrated to produce movement of the coccyx .…”