Health Medical Homework Help

BLOOD PRESSURE and HEART RATE

Preparation: Ch. 9 from course text.

Research Resources:http://www.unm.edu/~lkravitz/Article%20folder/rest…

http://www.mayoclinic.com/health/high-blood-pressu…

Monitoring systemic blood pressure with a sphygmomanometer and stethoscope has traditionally been the best noninvasive method of evaluating the health of the cardiovascular system. A cuff with an inflatable bladder is applied to a limb. The pressure in the bladder is increased to compress and occlude the artery. As the pressure is released, the blood resumes flow through the artery. The sounds of the blood flow (Korotkoff sounds), heard through the stethoscope, are those caused by the oscillations of the arterial walls. The first sound detected on pressure release is considered to occur when the intra-arterial pressure exceeds the bladder pressure. This is read on the manometer as the peak systolic pressure. The cessation of sound indicates the end-diastolic pressure. The blood pressure fraction, systolic pressure/diastolic pressure represents the peak and lowest pressures applied against arterial walls during each cardiac cycle.

Application

During exercise conditions a larger cardiac output is necessary to sustain the working muscles. Systolic pressure must increase to accommodate this need. Diastolic pressure may remain the same as it was at rest or it may decrease.

Differences in blood pressure response occur in arm exercise versus leg exercise, when comparing dynamic or isotonic exercise with isometric contractions, and as a result of resistance training.

Blood pressures are significantly higher in arm exercise than in leg exercise. Activation of small muscles causes a sympathetically induced vasodilation in the muscles involved. Concurrently, a vasoconstriction occurs in the larger, inactive muscles. This vasoconstriction represents more resistance in the system to blood flow and blood pressure increases.

In isometric contractions systolic and diastolic pressures along with heart rate are increased. This increase begins at contractions as small as 15% MVC. As the contraction is held, the pressure continues to gradually increase, ie. there is not steady state response. Isometric work in large muscle groups contracting with a great force can induce systolic pressures in excess of 300 mmHg and diastolic pressures over 150 mmHg.(Astrand p. 192). In the aging individual or in a person who exhibits a high risk coronary profile, these pressures could be life-threatening. Diagnostic exercise testing is contraindicated when resting systolic pressure exceeds 200 mmHg or diastolic pressure is greater than 120 mmHg. ACSM criteria for stopping a maximal exercise test is a systolic response of 250 mmHg or a diastolic response of 120 mmHg.

Objectives:To understand the importance of the blood pressure measurement in fitness screening.

To describe expected changes in blood pressure with different modes of exercise.

To recognize differences in blood pressure response with arm and leg exercise.

Equipment and Supplies

Stop watch

Data Collection

1. Locate the brachial or radial artery. Take your pulse for 1:00 of rest.

HR (rest) = _____________bpm

See the following videos.

** Do body weight squats or a total body exercise such as jumping jacks for 3-5 minutes and then record the following data. The key is to get the heart rate elevated and then measure blood pressure. Perhaps perform 20 to 30 jumping jacks or squats followed by a brief rest of 10-15 seconds and then perform more of the jumping jacks or squats until the 3-5 minutes are up. Then record data.

HR = ___________ bpm after exercise

Data Interpretation and Research Findings

(Please read the text and the two cited research articles before answering these.)

1. Why would you expect an increase in blood pressure with increasing intensities of exercise?

2. How do the following change from resting to exercise conditions?

Systolic Pressure ___________________

Diastolic Pressure ___________________

3. Describe the differences that you would expect in heart rate and blood pressure response to arm v. leg exercise during submaximal exercise and at maximal intensity.

Submaximal-

Maximal –