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Cardiopulmonary and metabolic responses were studied in 12 healthy males aged 45 +/- 7 yr (mean +/- SD) during 25 min of cycling exercise with (WW) and without (NW) arm swing with wrist weights at 60% and 75% of their maximal heart rate reserve (MHRR). Cycling leg work was adjusted in order to produce a constant 60% and 75% of MHRR during WW and NW sessions. The results revealed that during both exercises the cardiopulmonary and hemodynamic responses were similar. However, during the NW sessions lactic acid (LA) levels were significantly (P less than 0.01) higher than those observed during WW sessions (3.2 +/- 0.9 and 5.4 +/- 1.5 mm.l-1, vs 2.9 +/- 0.9 and 3.8 +/- 1.3 mm.-1), as were ratings of perceived exertion (RPE) (13.2 +/- 1 and 14.4 +/- 0.6, vs 12.2 +/- 1 and 13.4 +/- 1.5). These data indicated a similar pattern of hemodynamic and respiratory responses to NW and WW cycling exercises, while LA and RPE were lower in WW cycling. It is therefore suggested that arm swing with wrist weights may be a beneficial mode of exercise, distributing the workload on a larger muscle mass while maintaining the target heart rate. Thus, it enables a lower reliance on anaerobic metabolism and a lower perceived exertion.

In brief Carotid pulse counting is widely used to monitor exercise intensity. However, some researchers believe it may underestimate postexercise heart rates by initiating the carotid sinus reflex. This study compared carotid, radial, and ECG pulse rates in 20 asymptomatic adults. The authors concluded that carotid pulse counts can be used safely by many healthy adults, but because at least one subject had low heart rate counts after carotid palpations, they present some guidelines: Exercisers should (1) perform the procedure correctly, (2) periodically compare the carotid and radial pulses, and (3) exercise at the lower range of their target heart rate zone.

The author sets out to show why cardiac patients should follow an exercise regimen and that the important psychological benefits achieved by an exercise rehabilitation programme relate to the healing concept - to making the patient whole again. In addition, the capacity for physical work increases as does the “angina threshold". The safety of the patient is ensured by prescribing exercise based on results of the target heart rate concept. Finally, the author defends walking and jogging as the ideal mode of exercise.

The authors challenge methods of measuring exercise capacity based on mets or target heart rate. The most accurate criterion may be a percentage of maximum functional heart rate.

We attempted to determine whether graded exercise testing (GXT) soon after a myocardial infarction (MI) using an unlimited metabolic equivalent (MET) level and target heart rate (HR) of 90% of the age-predicted maximal HR 1) is a safe procedure and 2) yields prognostic results different from tests that use lower level end points. We administered GXT to a random sample of 85 patients at a mean of 14.8 days post-MI. End points that included ST-segment depression (STD), angina pectoris (AP), ventricular ectopic activity, and achieved MET level during testing were evaluated as predictors of cardiac events that include death, recurrent nonfatal MI, and coronary artery bypass graft surgery. We conducted short-term follow-up monitoring for one year after the initial MI and long-term follow-up monitoring for a mean of 864.7 days. No serious complications occurred during testing. Angina pectoris, STD accompanied by AP, and achieved MET level were predictive ( p < .05) of future fatal and nonfatal cardiac events during the first year of follow-up monitoring. Fifty-nine percent of the patients with AP suffered a subsequent cardiac event within one year, whereas only 17% of those without AP experienced another cardiac event. Sixty-seven percent of the patients with both STD and AP had a subsequent cardiac event within one year, but only 22% of those without AP and STD had a subsequent cardiac event. For the long-term follow-up monitoring, the presence of AP and a low achieved MET level during testing were associated with subsequent cardiac events. Sixty-four percent of the patients with AP during GXT had a subsequent cardiac event, whereas only 35% of those without AP during the GXT experienced another cardiac event. We concluded that GXT administered soon after an MI is safe and that the presence of AP, with or without STD, and a low achieved MET level during testing help to identify patients having an increased risk of experiencing cardiac morbidity and mortality.

The validity of systolic time intervals (STI) in predicting left ventricular dysfunction is still doubtful. Weissler (1) found good correlation between invasively determined parameters of left ventricular function and STI; he claimed to be able to predict the severity of left ventricular dysfunction from the ratio between the pre-ejection period (PEP) and the left ventricular ejection time (LVET) at rest. No information on sensitivity or specificity is available.

Accurate, reproducible, radionuclide ventriculo-graphic (RNV) studies are dependent upon careful attention to details in all parameters when acquiring and processing data. Each aspect of these details is like a link of a chain — the weakest link can cause a breakdown of accuracy of the measurement of global function and affect the quality of functional images.

In Reply.— Only one patient of our group (patient 5) continued to smoke cigarettes despite our repeated urging to stop. After reversible ventricular fibrillation, he had coronary arteriography and had noticeable lesions that were deemed operable. He refused surgery, however, and we thought that he should not exercise. With regard to types of anaerobic activities, we do use "short bursts" of such in our session. The patient's program is gradually increased from a walking program to a jogging program, always setting the target heart rate at 75% to 85% of the maximum tolerated heart rate on his treadmill testing. With regard to graduation of patients, we do think that some patients can leave a supervised exercised program. Many exercise programs now have an initial therapeutic phase of exercise that is medically supervised and usually entails the first 12 weeks after the cardiac event. After this, certain patients can be graduated

When exercise testing 159 patients with prior myocardial infarction, we identified 39 who were limited by fatigue. This group was all in sinus rhythm; none were taking drugs likely to impair the chronotropic response of the heart; none experienced chest pain or developed ischemic ECG changes

Fourteen untrained females (age 19 +/- 1, range 18-21) were studied to examine the heart rate-VO2 relationship during a single aerobic dance training session. These findings were used to help explain the changes in VO2max resulting from an aerobic dance training program. VO2max and body composition were determined before and after an 8 wk training period. In addition, the heart rate-VO2 responses to an aerobic dance training session were monitored and compared to the heart rate responses of treadmill jogging performed at the same VO2. The aerobic dance session elicited a significantly lower oxygen pulse than did treadmill exercise (7.2 +/- 0.3 vs 8.1 +/- 0.8 ml.beat-1; P less than 0.01). There were no significant changes in percent body fat, whereas VO2max increased by 11% (34.4 +/- 0.9 vs 38.1 +/- 0.8 ml.kg-1.min-1; P less than 0.05). No significant changes in any of the parameters tested were observed in 10 untrained controls. These findings indicate that the heart rate elicited from aerobic dance represents a lower relative exercise intensity (VO2) than that of running. Therefore, the assumption that aerobic dance training produces the same cardiovascular adaptations as running training when performed at the same target rate may be unwarranted.

(1987). What Is Target Heart Rate? The Physician and Sportsmedicine: Vol. 15, No. 1, pp. 214-214.