Gender Differences In Cardiovascular Responses Research Articles

Gender differences in cardiovascular response to upper extremities isometric exercise in normotensive young subjects

Background: Isometric exercises are a part of our activities and many occupational task. Isometric exercises produce a characteristic increase in blood pressure (BP). These provide pressor stimuli to the cardiovascular system, through efferent sympathetic pathways, with a resultant increase in heart rate (HR) and BP. Although isometric exercise such as handgrip testing has been reported to cause an increase in cardiovascular parameters, the response depends on the volume of muscle mass involved, duration, intensity, number of contraction, and workload. Previously a number of studies have been done to study the gender variation in cardiovascular response to upper extremities handgrip exercises but have shown conflicting results. Hence, this study is an endeavor to evaluate the difference in cardiovascular response to isometric exercise in normotensive young males and females. Aims and Objectives: The aim of the study was to determine the HR and BP response to isometric exercise in healthy normotensive males and females. Materials and Methods: One hundred medical students; 50 males and 50 females of age group 18–22 years satisfying the inclusion criteria were selected. Anthropometric measurements, that is, height and weight were taken. Resting BPs systolic BP (SBP) and diastolic BP (DBP) were recorded. Isometric contraction was held till 60 s using the handgrip dynamometer at 40% of the maximal voluntary contraction (MVC). Post-exercise HR and BP were recorded and compared. Results: Isometric handgrip exercise induces a pressor response and causes an increase in the HR and BPs irrespective of gender. Conclusion: This study concludes that isometric exercise brings about an increase in HR and BP. The response being more pronounced in males than in females.

A cross-sectional study of gender differences in cardiovascular responses to orthostatic tolerance test in adolescents

Background: Clinical data show higher incidence of postural hypotension in women than men. Clinicians make use of orthostatic tolerance test (OTT) to investigate such a situation and also in other varieties of clinical disorders ranging from most common disorders such as diabetes, hypertension leading to autonomic neuropathy to very rare disorders such as Shy-Drager syndrome and dysautonomias. This study will help to assess gender differences in cardiovascular response to orthostatic challenge. Aims and Objectives: The objective of the study was to evaluate the gender differences in cardiovascular responses such as change in systolic blood pressure (BP), diastolic BP, heart rate (HR), and mean arterial pressure (MAP) during OTT in 16–20 years of age group. Materials and Methods: The present cross-sectional study was conducted in 34 males and 36 female students of the age group of 16–20 years. The autonomic test used to assess orthostatic tolerance was OTT which is widely used for routine clinical evaluation of autonomic dysfunction. HR and BP changes during the orthostatic challenge were recorded, and 30:15 ratio was calculated from R-R interval of electrocardiogram ECG recording during the challenge. Results: Among the baseline parameters of males and females only HR, diastolic BP, and MAP were comparable. BP response during orthostatic challenge showed that MAP was significantly lower for females than males (P < 0.05). HR response was not statistically significant. Conclusion: The values being significantly lower for females than males this study helped to support the fact that women have less responsiveness to BP regulation during an orthostatic challenge in adolescents.

Gender differences responses in isometric exercise

Abstract: Gender differences in cardiovascular responses to isometric exercise for sitting posi-tion and spine.The purpose of this study was to 1) determine whether cardiovascular responses to isometric exercise differ between genders, and 2) to determine if the behavior affects cardiovas-cular responses to isometric hand tightening (IHG) exercise.Sixteen women and sixteen men (age 22.6 ± 4.2 years) performed two tests (seated or spine) IHG maximum trials at 40% MVC a week away.Blood pressure (BP) and heart rate (HR) measurements were collected at rest (RT), the first minute of exercise (M1), before failure (PF), and 30 s of recovery after failure (RC).Mean arterial pressure (MAP), pulse pressure (PP), and the rate of pressure produces (RPP) were calculated from BP and HR data.Tests showed considerable time by gender interactions for diastolic blood pressure (DBP) and MAP. Males had DBP significantly higher than women in M1 (105.46 ± 14.97 vs. 92.59 ± 13:14 mmHg), PF (122.46 ± 11.23 vs 109.50 ± 13.72 mmHg) and RC (85, 83 ± 4.11 vs. 73.46 ± 8.35 mmHg) and higher MAP measurements that women in M1 (120.32 ± 13.76 vs 105.43 ± 13.76 mmHg), PF (136.44 ± 8.65 vs. 24.31 ± 13:34 mmHg), and RC (100.44 ± 8.21 vs. 87.67 ± 8.26 mmHg).DBP, MAP, and HR were significantly higher in the sitting position than in the spine position for both sexes.Conclusions: 1) men significantly increase MAP and DBP after starting the exercise submaxi-mal IHG through recovery regardless of position, 2) women have significantly lower measurement of blood pressure than men along the submaximal despite exercising attitude and 3) The attitude has important effects on the cardiovascular response during exercise submaximal IHG.4) The force exerted varies significantly in standing position compared to other positions.

Effort analysis of gender differences in cardiovascular response: Further evidence involving a traditionally feminine incentive

Participants were presented a moderately- or impossibly difficult cumulative mental addition task with instructions that they could win a traditionally feminine- or masculine incentive if they achieved a 90% success rate. When the incentive was feminine, systolic blood pressure responses during the task period were stronger under moderately difficult conditions among women, but low irrespective of difficulty among men – creating a gender difference only when difficulty was moderate. By contrast, when the incentive was masculine, systolic-, mean arterial- and, to a lesser degree, diastolic blood pressure responses during the task period were stronger under moderately difficult conditions irrespective of gender. The former finding confirmed expectations and adds substantively to the body of evidence favoring a recent effort analysis of gender influence on CV response to performance challenge. The latter findings conflict with what was first expected, but can be understood in terms of post hoc reasoning extended in light of participants’ ratings of the masculine incentive.

Variation and association of body mass index with myocardial oxygen consumption: A gender based study in young population

Background: Regular exercise improves health and prevents many diseases. Exercise testing can be used as a diagnostic tool to unmask subclinical conditions such as coronary artery diseases and also monitor the effectiveness of therapeutic measures. Rate pressure product is a measure of stress put on cardiac muscle based on heart rate and systolic blood pressure. Numerous studies attempting to explain gender differences in cardiovascular response to isometric exercise are inconsistent at best and conflicting. Aims and Objective: The purpose of this study was to determine if the cardiovascular responses to dynamic exercises differ between healthy normotensive men and women students depending on their BMI ratio. Materials and Methods: This study consisted of young individuals (127 men and 123 women) of age group 18–20 years studying in first-year MBBS. Depending on their anthropometric measurements, classification was done as, normal, overweight, and obese groups based on WHO recommendations. Blood pressure and heart rate were recorded before, immediately after cessation of exercise, after 3 min, and after 5 min of recovery. MVo2 was measured by the rate pressure product (RPP) calculated as product of heart rate and systolic blood pressure. Result: Postexercise HR, SBP, DBP, and RPP were significantly greater in men than women. Highly significant increase in postexercise HR, SBP, DBP and RPP was observed in men compared to women. Conclusion: Men undergo significant changes in cardiac output, total peripheral resistance, or increase in level of circulating catecholamines mainly epinephrine with many possible explanations.

Cardiovascular responses to caffeine by gender and pubertal stage.

Caffeine use is on the rise among children and adolescents. Previous studies from our laboratory reported gender differences in the effects of caffeine in adolescents. The purpose of this study was to test the hypotheses that gender differences in cardiovascular responses to caffeine emerge after puberty and that cardiovascular responses to caffeine differ across the phases of the menstrual cycle. To test these hypotheses, we examined heart rate and blood pressure before and after administration of placebo and 2 doses of caffeine (1 and 2 mg/kg) in prepubertal (8- to 9-year-olds; n = 52) and postpubertal (15- to 17-year-olds; n = 49) boys (n = 54) and girls (n = 47) by using a double-blind, placebo-controlled, dose-response design. There was an interaction between gender and caffeine dose, with boys having a greater response to caffeine than girls. In addition, we found interactions between pubertal phase, gender, and caffeine dose, with gender differences present in postpubertal, but not in prepubertal, participants. Finally, we found differences in responses to caffeine across the menstrual cycle in post-pubertal girls, with decreases in heart rate greater in the midluteal phase and blood pressure increases greater in the midfollicular phase of the menstrual cycle. These data suggest that gender differences in response to caffeine emerge after puberty. Future research will determine the extent to which these gender differences are mediated by physiological factors, such as steroid hormones, or psychosocial factors, such as more autonomy and control over beverage purchases.

English

Studies on gender differences in cardiovascular responses to isometric exercise have been numerous and conflicting. The present study aims to measure the Endurance time and Blood Pressure response to sustained isometric exercise using handgrip dynamometer in both male and female. Thirty healthy subjects (16 males, 14 females) were taken for the study and the Endurance time and Blood Pressure response was determined and data obtained was analysed using SPSS software version -16. The present study showed that the Endurance time was longer in females as compared to males while the Blood pressure response was higher in males as compared to females. We can conclude from our study that females have less muscle mass so there is less mechanical compression of vasculature & hence less imbalance between blood supply & demand & delayed fatigability, thus accounting for the prolonged endurance time& lesser blood pressure response.

Gender determination of effort and associated cardiovascular responses: When men place greater value on available performance incentives

Participants were presented an easy or difficult mental addition task and led to believe that they could win a traditionally masculine incentive by meeting a certain performance standard. As expected, blood pressure and heart rate responses during the work period were stronger under difficult conditions than easy ones among men but low under both difficulty conditions among women. Findings support the suggestion from a conceptual analysis grounded in motivation intensity theory that gender differences in cardiovascular response could be partially understood in terms of effort processes that occur where men and women place different value on available performance incentives.

Gender Differences in Subjective and Physiological Responses to Caffeine and the Role of Steroid Hormones.

We have shown previously that male and female adolescents differ in their responses to caffeine, but to date, the mechanisms underlying these gender differences are unknown. The purpose of this study was to test the hypothesis that differences in circulating steroid hormones mediate gender differences in response to caffeine. Subjective and physiological responses to caffeine were tested in adolescents using a double-blind, placebo controlled, crossover design. Participants were tested every 2 weeks for 8 weeks and received placebo and caffeine (2 mg/kg) twice each. Females were tested with placebo and caffeine in each phase of their menstrual cycle. Salivary concentrations of testosterone, estradiol, and progesterone were also measured. Males showed greater positive subjective effects than females. In females, higher levels of estradiol were associated with little or no subjective responses to caffeine, but lower levels of estradiol were associated with negative subjective responses to caffeine relative to placebo. There were gender differences in cardiovascular responses to caffeine, with males showing greater decreases in heart rate after caffeine administration than females, but females showing greater increases in diastolic blood pressure than males after caffeine administration. These gender differences may be related to steroid hormone concentrations. Blood pressure responses to caffeine were lower in males when estradiol was high, but higher in females when estradiol was high. When taken together, these findings suggest that males and females differ in their responses to caffeine and that these differences may be mediated by changes in circulating steroid hormones.

Gender Differences in Cardiovascular Response to Upper Extremities Isometric Exercises in Normotensive Subjects

Background and objective: Studies on gender differences in cardiovascular responses to isometric exercise have been numerous and conflicting. The objective of this study was to determine if the cardiovascular responses to upper extremities isometric exercises differ between apparently healthy male end female subjects.&#x0D; Methods: One hundred and sixty apparently healthy adults with the mean age of 39.0 ± 11.04 years were consecutively recruited into the study. This consisted of 80 males (39.0 ± 10.82 years) and 80 females (38.96 ± 11.25). Data were obtained on participants' age, height, weight, body mass index, blood pressure, heart rate, and Rate Pressure Product. Data were summarized using descriptive statistics of mean and standard deviation. Independent t-test was used to compare physical characteristics between genders while repeated measure of ANOVA was used to compare the pre and post isometric exercises cardiovascular parameters between genders. Level of significance for all tests was set at p&lt; 0.05. &#x0D; Results: The baseline cardiovascular parameters were not significantly different (p&gt; 0.05) between the male and the female participants. The post exercise cardiovascular parameters were significantly greater (p&lt; 0.05) than the baseline values without gender bias. However, the post exercise SBP and RPP were significantly different (p&lt; 0.05) between the male and the female participants respectively. &#x0D; Conclusion: Isometric exercises of the upper limbs can lead to a significant increase in cardiovascular parameters among apparently healthy male and female subjects. Higher ventricular contraction is evoked among males leading increased SBP while the myocardial oxygen uptake and the measure of the oxygen consumption of the heart muscles of the female participants in response to upper extremities isometric exercises is higher than that of the males as demonstrated by the RPP.&#x0D; Key words: Isometric exercises, cardiovascular response, upper extremities exercises.

Gender differences in cardiovascular response to dementia caregiving.

This study examined gender differences in cardiovascular responses to laboratory-based stress, as well as in ambulatory hemodynamic (i.e., blood pressure and heart rate) functioning among caregivers of persons with dementia. Participants were 25 men and 25 women caregivers, matched on age, type of care recipient's dementia, and relationship to the care recipient. After cardiovascular reactivity to a laboratory-based caregiving stressor was assessed, the ambulatory hemodynamic functioning levels of caregivers were measured in caregivers' natural environments. Female caregivers displayed greater systolic and diastolic blood pressure reactivity to a laboratory-based stress task (i.e., discussing caregiving difficulties) compared with male caregivers (p < or =.01). In contrast, no gender differences were found for ambulatory hemodynamic functioning when aggregated overall or when in the presence of the care recipient. Laboratory-based findings suggest that female caregivers experience greater blood pressure reactivity to caregiving-related stress than do male caregivers. However, these laboratory-based gender differences may not generalize to differences in hemodynamic functioning in caregivers' daily lives.

Gender Differences in Cardiovascular Responses to Sphygmomanometric Measurements

Objective: To study gender differences of cardiovascular responses due to painful stimuli during sphygmomanometry. Methods: We studied 80 subjects (40 women, 40 men). Blood pressure (BP) was determined continuously and noninvasively using a Finapres device (Penaz technique). The painful stimulus was administered by inflating the arm cuff of a sphygmomanometric device to 300 mmHg maximum pressure. Results: During cuff inflation systolic blood pressure (SBP) increased in women (+3.7 mmHg, SD = 9.9), but was unchanged in men (repeated measures ANOVA, P &lt; .05). Diastolic blood pressure (DBP) and heart rate did not show significant changes. Cycle and oral contraceptives did not influence cardiovascular reactivity in the female subpopulation. Women reported a different pain quality but not intensity. Conclusions: Women and men exhibit a slightly different vascular reactivity to painful stimuli. Since cycle and hormonal contraception did not influence reactivity, hormonal influences seem to play a minor role. However, different pain perception might account for gender differences in vascular reactivity.

286 Gender differences in cardiovascular response to stress in coronary patients

286 Gender differences in cardiovascular response to stress in coronary patients

223 Gender differences in cardiovascular response to stress in coronary patients

223 Gender differences in cardiovascular response to stress in coronary patients

Gender differences in cardiovascular responses to the cold hand pressor test and facial cooling.

To test the hypothesis that changes in systemic vascular resistance (SVR) contribute to the differences in arterial blood pressure responses between men and women to local cold pressor tests, nine normotensive men (25.9 +/- 5.9 years old) and women (24.4 +/- 5.9 years old) performed the cold hand pressor test (CPT; 6 min in 5 degrees C water) in the supine position. A subgroup of men (n = 5) and women (n = 5) from the CPT were exposed to 6 min of facial cooling (FC) by circulating cold water (5 degrees C) through a perfusion mask. Using standard auscultatory techniques, pre-experimental systolic and diastolic blood pressures were found to be significantly higher (p < or = 0.05) in males than females. During the initial 2 min of CPT and FC, both males and females experienced similar relative increases in pressure. Thereafter, only the males maintained an elevated pressor response, whereas the females progressively declined. The gender-related trends in blood pressure can be explained by differences in SVR, with the males exhibiting significantly greater changes in SVR than females during min 4-6 in CPT. Heart rate increased (p < or = 0.05) in both groups, with the greater rise occurring in females at each minute of CPT. Throughout FC, the changes in SVR were similar between groups, with the exception of the 6-min value being greater than baseline in men but not women. No differences in heart rate or cardiac output were observed between groups during FC.(ABSTRACT TRUNCATED AT 250 WORDS)

Hemodynamic adjustments to laboratory stress: the influence of gender and personality.

Exaggerated cardiovascular reactivity to psychological stress is a potential pathophysiological mechanism linking behavior and cardiovascular disease. Because of the recognized gender differences in incidence of cardiovascular disease, potential gender differences in cardiovascular reactivity to laboratory stressors have been evaluated. The current study examined the cardiovascular responses of a total of 42 young women (N = 22) and men (N = 20) undergoing a laboratory protocol including the following: a nonverbal math task, a mirror tracing task, the Stroop Color-Word interference task, and an isometric handgrip task. In addition to the assessment of heart rate and blood pressure, cardiac output, stroke volume, total peripheral resistance and preejection period were assessed by impedance cardiography. A number of personality characteristics that vary in prevalence by gender were also measured to evaluate their ability to explain potential gender differences in cardiovascular responses. Results indicated that men responded with greater total peripheral resistance and systolic and diastolic blood pressure responses than did women on a subset of tasks, whereas women exhibited larger increases in heart rate on a subset of tasks. Thus, men were more likely to be "vascular" reactors, with women being more likely to be "cardiac" reactors. Personality characteristics did differ between men and women, but did not explain significant variance in the gender differences in cardiovascular responses. We conclude that additional studies should focus on experimental manipulations of potential physiological mechanisms responsible for these differences, such as reproductive hormones.