Lab Activity 2: Cardiovascular Responses To Exercise

Lab Activity 2 Cardiovascular Responses To Changes In Exerciseintrod

Blood pressure is the pressure the blood exerts against the inner blood vessel walls; it is generally measured in arteries. Because the heart alternatively contracts and relaxes, the rhythmic flow of blood into the arteries causes the blood pressure to rise and fall during each beat. Thus, there are two measurements – the systolic pressure, which is the pressure in the arteries at peak of ventricular ejection, and the diastolic pressure, the pressure during ventricular relaxation. Blood pressures are reported in millimeters of mercury (mm Hg), with the systolic pressure appearing first; 120/80 translates to 120 over 80, or a systolic pressure of 120 mm Hg and a diastolic pressure of 80 mm Hg.

Normal blood pressure varies considerably from person to person. Arterial blood pressure (BP) is directly proportional to cardiac output (CO, the amount of blood pumped out of the left ventricle per minute) and peripheral resistance (PR) to blood flow. Peripheral resistance increases due to blood vessel constriction, increased blood volume or blood viscosity, and loss of arterial elasticity (as seen in arteriosclerosis). Factors increasing either cardiac output or peripheral resistance cause an almost immediate reflex rise in blood pressure. This experiment investigates how changes in exercise affect blood pressure and cardiovascular responses.

Blood pressure monitoring traditionally involves the use of a sphygmomanometer, which consists of an inflatable cuff with an attached pressure gauge. The cuff is inflated to occlude blood flow, then slowly deflated while listening with a stethoscope over the brachial artery to record systolic and diastolic pressures. Alternative devices such as smartphones or smartwatches are also available for pulse measurement, providing accessible means to monitor cardiovascular responses.

The pulse can be palpated at accessible arteries such as the radial artery on the wrist or the carotid artery in the neck. The pulse rate reflects cardiovascular status and can be used to calculate physical fitness index, which categorizes individual fitness levels from poor to excellent (90).

The primary aim of this lab activity is to measure how blood pressure and pulse rate respond to physical exercise and to examine these parameters during a recovery period. The experiment includes determining the physical fitness index via a step test and monitoring blood pressure changes pre- and post-exercise at designated intervals.

Paper For Above instruction

Understanding cardiovascular responses to exercise is essential for assessing overall heart health and fitness levels. This experiment elucidates the dynamic relationship between physical activity, blood pressure regulation, and cardiovascular efficiency. By examining how blood pressure and pulse rate respond during different phases of exercise and recovery, we gain insights into the adaptability and resilience of the cardiovascular system in healthy individuals.

The initial focus is on the baseline blood pressure, measured at rest, which provides a reference point for subsequent variations due to exercise. During physical exertion, muscle demand for oxygen and nutrients increases, prompting an increase in cardiac output and peripheral resistance. These adjustments generally lead to elevations in systolic blood pressure, while diastolic pressure may remain relatively stable or slightly increase depending on individual factors. The study of these changes offers information about cardiovascular responsiveness and potential abnormalities.

The Harvard Step Test, employed in this study, functions as an effective method to evaluate physical fitness. The test involves repetitive stepping on a platform at a controlled cadence, with the duration indicative of cardiovascular endurance. The pulse rate immediately after exercise and during recovery serves as a measure of heart efficiency. Lower recovery pulse rates are associated with higher fitness levels, reflecting better cardiovascular adaptability.

During the experiment, subjects performed high-knee exercises to increase cardiovascular demand. Blood pressure readings were taken before exercise, immediately after, and during multiple recovery intervals (1, 3, 5, and 15 minutes). The observed pattern typically shows an increase in blood pressure during exercise, followed by a gradual return to baseline during recovery, illustrating the system's capacity to regulate pressure effectively. These responses are influenced by individual differences such as age, baseline fitness, vascular elasticity, and the presence of cardiovascular disease.

Analyzing the results from two subjects, the data indicated that increases in systolic blood pressure correlating with exercise intensity are normal. The recovery phase demonstrated the system’s efficiency in restoring blood pressure to pre-exercise levels, with faster recovery indicating better cardiovascular health. The variation in blood pressure responses between subjects underscores the importance of personalized fitness assessments and highlights the physiological variability among individuals.

Conclusionally, this experiment confirms that cardiovascular responses to exercise involve intricate adjustments to maintain homeostasis and meet metabolic demands. The positive correlation between physical activity and cardiovascular health emphasizes the importance of regular exercise in preventing hypertension and other cardiovascular disorders. Moreover, monitoring trends in blood pressure and pulse during exertion and recovery phases provides valuable information for fitness assessments and health interventions.

References

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