Arterial blood pressure response to heavy resistance exercise

The purpose of this study was to record the blood pressure response to heavy weight-lifting exercise in five experienced body builders. Blood pressure was directly recorded by means of a capacitance transducer connected to a catheter in the brachial artery. Intrathoracic pressure with the Valsalva maneuver was recorded as mouth pressure by having the subject maintain an open glottis while expiring against a column of Hg during the lifts. Exercises included single-arm curls, overhead presses, and both double- and single-leg presses performed to failure at 80, 90, 95, and 100% of maximum. Systolic and diastolic blood pressures rose rapidly to extremely high values during the concentric contraction phase for each lift and declined with the eccentric contraction. The greatest peak pressures occurred during the double-leg press where the mean value for the group was 320/250 mmHg, with pressures in one subject exceeding 480/350 mmHg. Peak pressures with the single-arm curl exercise reached a mean group value of 255/190 mmHg when repetitions were continued to failure. Mouth pressures of 30-50 Torr during a single maximum lift, or as subjects approached failure with a submaximal weight, indicate that a portion of the observed increase in blood pressure was caused by a Valsalva maneuver. It was concluded that when healthy young subjects perform weight-lifting exercises the mechanical compression of blood vessels combines with a potent pressor response and a Valsalva response to produce extreme elevations in blood pressure. Pressures are extreme even when exercise is performed with a relatively small muscle mass.     

Clinical importance of the renin-angiotensin system in chronic heart failure: double blind comparison of captopril and prazosin.

Nineteen patients with chronic heart failure participated in a double blind crossover trial of captopril and prazosin--two drugs with differing neuroendocrine effects--to determine whether neuroendocrine changes could explain clinical and haemodynamic responses to treatment. Patients were assessed before and after acute and long term (four weeks'') treatment with each drug given in random order. Sixteen patients completed the study. During captopril haemodynamic improvement was maintained by inhibition of the renin-angiotensin system. Breathlessness was relieved in 15 patients and exercise capacity increased. During prazosin a reduction in systemic vascular resistance was maintained, but plasma renin activity and aldosterone and noradrenaline concentrations increased, fluid retention developed, and clinical benefit did not occur. These results suggest that clinical and haemodynamic responses to long term vasodilator treatment for chronic heart failure are related to neuroendocrine changes. In patients with chronic heart failure inhibition of the renin-angiotensin system results in clinical benefit, whereas inhibition of the alpha adrenergic system does not.     

Inadequate cervical cytology—the need to audit individual smear takers'' inadequate rates

In order to assess the performance of individual smear takers, their rates of inadequate smears, due to insufficient material, were monitored between 1992 and 1996. Although the yearly average clinic inadequate rates were all at acceptable levels, there was great variation of rates between smear takers, ranging from 0% to 19.5%. Identification of individuals with unacceptably high inadequate rates allowed them to undergo further training. Continuous monitoring of these inadequate rates can be used to measure levels of performance amongst all smear takers, but is particularly useful for new smear takers, or those who have required retraining.