Reliability of heart rate variability threshold and parasympathetic reactivation after a submaximal exercise test

P76 Background. Heart Rate Recovery at two minutes post exercise (HRR2) was reported to be a predictor of death in the US-Lipid Research Clinics (LRC) Study. Objective. To extend study of HRR2 to the USSR-LRC population, with higher mortality rates and cardiovascular (CVD) risk factor levels. Design and methods. Among the LRC cohorts, using a standardized protocol, HRR2 after a treadmill submaximal test and CVD risk factors was measured in 1294 Russian and 1589 American men ages 39-60 years, free of coronary disease at baseline, not taking cardio-active drugs, followed for an average of 17.5 years for all cause mortality. Kaplan-Meier curves and stratified Cox proportional hazard models were employed for analysis. Results.There were 391 (30.2%) deaths in the Russian and 232 (14.6%) in the American men, and mean HRR2 was 59.6 bpm (95% CI 58.3-60.3) and 53.2 (CI 52.6-53.8) respectively. All cause mortality increased monotonically with decreasing HRR2 and was predicted by HRR2 adjusting for age, physical fitness, ST-T response, cholesterol and blood pressure, and alcohol intake in both samples. For each 15 bpm (1 SD) decrease in HRR2 the crude hazard rate ratio was 1.61 (95% CI 1.37, 1.89) in Russian and 1.37 (1.23, 1.51) in American men among smokers; upon adjustment the values were 1.34 (95% CI 1.16-1.56) and 1.39 (1.13-1.70) respectively. Conclusion. Delay in the recovery of heart rate after a submaximal exercise test was associated with all cause mortality, statistically independent of cardiovascular risk factors in both Russian and American men.The extension of these associations to a higher risk population, suggests the potential utility of HRR2 for CVD risk assessment.

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Correlation Between Cardiac Autonomic Function At Rest And Heart Rate Recovery After Submaximal Exercise Test

Medicine & Science in Sports & Exercise ◽

10.1249/01.mss.0000485611.50143.4e ◽

2016 ◽

Vol 48 ◽

pp. 203-204

Author(s):

Giliard L. Garcia ◽

Carlos J. Gomes ◽

Keila E. Fontana ◽

Luiz Guilherme G. Porto ◽

Luiz F. Junqueira ◽

...

Keyword(s):

Heart Rate ◽

Exercise Test ◽

Autonomic Function ◽

Heart Rate Recovery ◽

Submaximal Exercise ◽

Cardiac Autonomic Function ◽

Submaximal Exercise Test

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Resting Systolic Blood Pressure and Heart Rate at Work

Scandinavian Journal of Social Medicine ◽

10.1177/140349488000800306 ◽

1980 ◽

Vol 8 (3) ◽

pp. 117-123 ◽

Cited By ~ 1

Author(s):

Björn G. Jonsson ◽

Irma Åstrand

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Systolic Blood Pressure ◽

Exercise Test ◽

Submaximal Exercise ◽

Curvilinear Relationship ◽

Lower Heart Rate ◽

Men And Women ◽

Submaximal Exercise Test ◽

The Relationship

A random sample ( n = 1 050) of the population of a region in central Sweden performed a submaximal exercise test on bicycle ergometers. The participants were men and women aged 18 to 65 taking part in the REBUS study 1969–71 (3). This paper deals with the partial relationship between heart rate at different rates of work and systolic blood pressure measured at rest (SBP) controlling the influence of other predictors of heart rate. It was found that the relationship was non-linear and that individuals with a relatively high SBP had a lower heart rate than individuals with lower SBP. The curvilinear relationship was more pronounced in women and grew stronger with increasing rate of work.

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Determining Safe Participation in Aerobic Exercise Early After Stroke Through a Graded Submaximal Exercise Test

Physical Therapy ◽

10.1093/ptj/pzaa103 ◽

2020 ◽

Vol 100 (9) ◽

pp. 1434-1443

Author(s):

Elizabeth L Inness ◽

Anthony Aqui ◽

Evan Foster ◽

Julia Fraser ◽

Cynthia J Danells ◽

...

Keyword(s):

Heart Rate ◽

Aerobic Exercise ◽

Exercise Testing ◽

Exercise Test ◽

Stroke Rehabilitation ◽

Perceived Exertion ◽

Physical Therapists ◽

Submaximal Exercise ◽

Submaximal Exercise Test ◽

Exercise Induced

Abstract Objective The benefits of aerobic exercise early after stroke are well known, but concerns about cardiovascular risk are a barrier to clinical implementation. Symptom-limited exercise testing with electrocardiography (ECG) is recommended but not always feasible. The purpose of this study was to determine the frequency of and corresponding exercise intensities at which ECG abnormalities occurred during submaximal exercise testing that would limit safe exercise prescription beyond those intensities. Methods This study was a retrospective analysis of ECGs from 195 patients who completed submaximal exercise testing during stroke rehabilitation. A graded submaximal exercise test was conducted with a 5- or 12-lead ECG and was terminated on the basis of predetermined endpoint criteria (heart rate, perceived exertion, signs, or symptoms). ECGs were retrospectively reviewed for exercise-induced abnormalities and their associated heart rates. Results The peak heart rate achieved was 65.4% (SD = 10.5%) of the predicted maximum heart rate or 29.1% (SD = 15.5%) of the heart rate reserve (adjusted for beta-blocker medications). The test was terminated more often because of perceived exertion (93/195) than because of heart rate limits (60/195). Four patients (2.1%) exhibited exercise-induced horizontal or downsloping ST segment depression of ≥1 mm. Except for 1 patient, the heart rate at test termination was comparable with the heart rate associated with the onset of the ECG abnormality. Conclusion A graded submaximal exercise test without ECG but with symptom monitoring and conservative heart rate and perceived exertion endpoints may facilitate safe exercise intensities early after stroke. Symptom-limited exercise testing with ECG is still recommended when progressing to higher intensity exercise. Impact Concerns about cardiovascular risk are a barrier to physical therapists implementing aerobic exercise in stroke rehabilitation. This study showed that, in the absence of access to exercise testing with ECG, submaximal testing with conservative heart rate and perceived exertion endpoints and symptom monitoring can support physical therapists in the safe prescription of aerobic exercise early after stroke. Lay Summary It is recommended that people with stroke participate in aerobic exercise as early as possible during their rehabilitation. A submaximal exercise test with monitoring of heart rate, perceived exertion, blood pressure, and symptoms can support physical therapists in safely prescribing that exercise.

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Heart rate adaptation to exercise training in cardiac-denervated dogs

Journal of Applied Physiology ◽

10.1152/jappl.1982.52.6.1586 ◽

1982 ◽

Vol 52 (6) ◽

pp. 1586-1590 ◽

Cited By ~ 33

Author(s):

G. A. Ordway ◽

J. B. Charles ◽

D. C. Randall ◽

G. E. Billman ◽

D. R. Wekstein

Keyword(s):

Heart Rate ◽

Exercise Training ◽

Exercise Test ◽

Citrate Synthase ◽

Submaximal Exercise ◽

Treadmill Running ◽

Heart Rates ◽

Cardiac Denervation ◽

Submaximal Exercise Test ◽

Test Intensity

To determine the effect of cardiac denervation on the development of a training-induced decrease in heart rate at rest and during submaximal exercise, six cardiac-denervated (CD) and six sham-operated (SO) dogs were exercise trained by means of a 6-wk treadmill running program. Gastrocnemius citrate synthase activity increased significantly to the same degree in CD and SO dogs indicating that both groups were equally trained. Resting heart rates (RHR) for SO dogs decreased significantly from 64 +/- 4.8 to 51 +/- 3.2 beats/min (mean +/- SE) from pre- to posttraining. CD dogs showed no changes in RHR (95 +/- 3.5 to 96 +/- 5.3 beats/min). Heart rate responses of SO dogs to a standardized, submaximal exercise test decreased significantly from pre- to posttraining. However, CD dogs displayed no decrease in heart rate responses to the standardized, submaximal exercise test. Additionally, at pre- and posttraining, as heart rates rose in response to exercise test intensity, they increased to a significantly greater degree in SO dogs compared with CD dogs. The results indicate that in dogs, cardiac denervation prevents the decreases in resting heart rate and heart rate during submaximal exercise normally associated with endurance exercise training.

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