Determination of exercise training heart rate in patients on β-blockers after myocardial infarction

Abstract

The Karvonen formula underestimates the heart rate at the anaerobic threshold in beta-blocked patients, which may lead to undertraining of patients with coronary artery disease; we propose another formula more adapted to these patients.

Prescribing Aerobic Exercise Intensity without a Cardiopulmonary Exercise Test Post Stroke: Utility of the Six-Minute Walk Test

“…The cardiopulmonary exercise test (CPET) determines the ventilatory threshold (VAT), 16 which is a useful guide to determining the target intensity level for the prescription of exercise in healthy individuals and those with cardiovascular disease. [17][18][19] Prescribing exercise at a percentage of the peak heart rate or VO peak 2 attained on a graded exercise stress test may result in a suboptimal training intensity in individuals who may prematurely terminate a stress test because of stroke-related factors unrelated to cardiovascular end points such as neuromuscular disability. 20 The VAT is a submaximal intensity measure that does not necessitate the achievement of a "true" VO max 2 (i.e., an individual's maximal capacity to transport and use oxygen), is achievable by most people post stroke, 20 and is an important measure for gauging and guiding the exercise intensity prescription.…”

The Feasibility of Cardiopulmonary Exercise Testing for Prescribing Exercise to People After Stroke

“…The CPET determines the ventilatory anaerobic threshold (VAT), which represents the movement from aerobic to anaerobic metabolism, 11 and is recommended as an appropriate target intensity level for the prescription of exercise. [12][13][14] Achievement of maximal oxygen uptake (VO 2max ; ie, an individual's maximal capacity to transport and use oxygen) is another important measure used to prescribe exercise intensity. Therefore, VO 2max , VAT, and the level at which a clinically relevant abnormality (CRA) occurs are all critical measures for prescribing an exercise intensity that is both safe and effective.…”

Cardiopulmonary exercise testing in the early-phase of myocardial infarction

“…In our study, we observed that the AMIG showed lower aerobic functional capacity both in the AT and at peak exercise compared to the CG, demonstrated by the power, HR, VO 2 30 and Tabet et al 33 . The lowest functional capacity values presented by AMIG, in both at the AT and at peak exercise, can be attributed to two distinct mechanisms: 1) the presence of pathology and 2) to the use of betablocker therapy.…”

“…In this sense, the AMIG underwent to sub-maximal CPET 22±4 days (on average) after the AMI, as well as in the studies of Tabet et al 33 and Duru et al 34 , which evaluated the patients at 18 and 36 days (on average) after the AMI, respectively. During the CPET, the AMIG have not presented any signs or symptoms that limited its performance.…”

“…These drugs improve survival and reduce hospitalization in this group of patients, and its action on exercise tolerance is still contradictory 30,33,43,42 . The beta-blockers are able to partially antagonize the sympathetic activity, which reduces HR, the myocardial oxygen consumption and increases the time of left ventricular filling, with improve myocardial perfusion 44 .…”