Sammendrag
Introduction: Squatting, an active posture manoeuvre
imposes potent postural stress. Blood pressure and
heart rate changes, during change in posture, provide
information on performance of the baroreflexes and
haemodynamic homoeostasis. This study was aimed
at determining the cardiovascular responses to
squatting in young Black African men and women.
Method: Sixty five (M/F: 32/33) aged 16-30 years
were recruited. Systolic and diastolic blood pressure
(SBP, DBP) and heart rate (HR) were recorded in
sitting, standing and squatting positions. Mean arterial
blood pressure (MABP) and pulse pressure (PP)
were calculated. Differences in SBP, DBP, MABP,
PP and HR between squatting position and standing
were calculated at onset (0s), 60s and 120s of
squatting. Effect of squatting was determined using
Student’s T test and repeated measures ANOVA with
Bonferroni post hoc tests. Statistical significance was
determined at level of p < 0.05.
Result: Prompt squat increased SBP by 8.57 ± 1.71
mmHg, MAP by 3.57 ±1.03 mmHg, DBP by 1±1.09
mmHg, leading to augmentation of PP by 7.57 ± 1.07
mmHg, with a decrease in HR by 9.15 ±1.48 beats/
min. Women showed greater increase in DBP and
MAP compared with men during prompt squatting
(3.84 ±1.72 vs 1.76 ±1.18 mmHg; 6.00±1.71 vs
1.12±1.46 mmHg, p < 0.05). Sustained squatting
evoked greater increase in SBP, DBP and MABP in
women than men.
Conclusion: Squatting evoked increase in blood
pressure with augmentation of pulse pressure,
however, women showed greater increase in blood
pressure relative to men during squatting. The sex
differences require further investigation.
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