Prognostic Performance of Heart Rate Recovery on an Exercise Test in a Primary Prevention Population

The impact of two different aerobic exercise intensities on cardiometabolic parameters in type 2 diabetic patients: A randomized trial

BACKGROUND

Regular exercise significantly reduces cardiovascular risk and helps prevent primary and secondary cardiac events. However, the mechanisms through which exercise affects cardiovascular health remain unclear. This study investigates the acute effects of high-intensity interval training (HIIT) versus moderate-intensity continuous exercise (MOD) on endothelial function and glycemic control in patients with type 2 diabetes (T2D).

OBJECTIVES

The study aimed to compare the acute effects of a single session of HIIT and MOD on endothelial function, hemodynamic parameters, and blood glucose levels in T2D patients.

DESIGN

This was a randomized controlled trial (RCT).

SETTING

Conducted at the Laboratory of Cardiopulmonary Rehabilitation.

PARTICIPANTS

Fifty-seven sedentary patients with type 2 diabetes (39 women and 18 men) participated in the study.

METHODS

Participants were randomly assigned to either HIIT (10 sprints of 30 s at 85-100% of maximum heart rate, with 1-min active pauses) or MOD (continuous exercise at 60-70% of maximum heart rate for 30 min). Brachial artery flow-mediated dilation (%FMD) and blood glucose levels were measured before and immediately after the sessions.

RESULTS

HIIT significantly increased %FMD (9.3 ± 5.3% vs 20.05 ± 9.3%, p < 0.01) and reduced glucose levels (189 [106-335] mg/dL vs 149 [70-448] mg/dL, p < 0.01). Although MOD also showed positive responses, HIIT yielded more pronounced improvements in endothelial function.

CONCLUSION

HIIT is more effective for cardiovascular protection than MOD, although both exercises improve glycemic control in T2D patients. Higher %FMD is associated with better physical capacity and heart rate recovery, indicating a favorable prognosis.

Comparative Analysis of Waist-Height Ratio and Heart Rate Recovery for Predicting Coronary Heart Disease Risk Among Working Malaysian Women

Purpose

Coronary heart disease (CHD) is the most common cardiovascular disease leading to global mortality and is a major contributor to disability. As CHD is the main cause of death among women, early prediction of the risk of coronary heart disease would be useful. The Framingham risk score, waist-height ratio, and heart rate recovery have been used to predict CHD risk. The Framingham risk score is used to evaluate 10-year absolute risk of developing CHD. Waist Height Ratio is useful for early detection of the risk of heart disease in Malaysia, where obesity and metabolic syndrome are common across various demographics, because it is a reliable indicator of abdominal fat distribution. Heart Rate Recovery is a useful non-invasive method for early assessment of heart disease risk, featuring simplicity and the ability to represent both cardiovascular fitness and autonomic nervous system function. However, no study has compared waist-height ratio and heart-rate recovery as effective methods for predicting coronary heart disease. There is an increasing trend of CHD in Malaysia, particularly among females. Therefore, this study aimed to compare the effectiveness of waist-height ratio and heart-rate recovery in predicting the risk of coronary heart disease among working Malaysian women.

Methods

This is a cross-sectional study. Data on the Framingham risk score, waist-height measurement, and the 6-minute walk test (heart-rate recovery) were collected from 134 working women.

Results

The mean age of the participants was 39.13 ± 7.06 years. The results showed that the waist-to-height ratio had a weak but significant correlation with Framingham risk score (r = 0.18). However, heart rate recovery showed a negative correlation (r = -0.029) with the Framingham risk score.

Conclusion

The waist-height ratio is considered a more effective risk assessment method than heart-rate recovery for identifying the risk of coronary heart disease in working Malaysian women.

Effects of a physical therapist-driven individualized hybrid model of the exercise component of cardiac rehabilitation on patient outcomes: a prospective single group, time-series design

PURPOSE

The aim of this prospective single group, time-series study was to determine the feasibility, adherence, and effectiveness of an individualized physical therapist (PT)-driven hybrid model of the exercise component of cardiac rehabilitation (CR) that uses a novel intensity-recovery progression protocol (IRPP) and cardiac testing template (CTT) to assess achieved heart rate (HR) intensity, HR recovery, and intensity-recovery total to guide treatment.

METHODS

Assessment of a questionnaire, treadmill 6-min walk (6MW), 1-min sit-to-stand (1STS), 1-min step, and 1-min agility square tests were assessed on 100 participants. Compared to traditional CR the 36-visit 1:1 hybrid model was individualized using the IRPP program and CTT.

RESULTS

Adherence was 35% (timely) and 44% (overall) completion. The per-protocol analysis (PPA) and intent-to-treat (ITT) analysis suggest significant improvement in objective assessments baseline to visit 15 (PPA = 11 of 14) (ITT = 13 of 14), baseline to visit 30 (PPA = 12 of 14) (ITT = 12 of 14) and visit 15 to visit 30 (PPA = 9 of 14) (ITT = 10 of 14). Improvement beyond the minimal clinically important difference (MCID) was 94.3% in the 6MW and 91.4% in the 1STS.

CONCLUSIONS

The PT-driven IRPP program was feasible in terms of adherence and safety, showing significant improvement in a majority of assessments. Analysis of HR using the CTT may help clinical decision making for progression in CR.

Heart rate response and recovery in cycle exercise testing: normal values and association with mortality

AIMS

Chronotropic incompetence and impaired heart rate (HR) recovery are related to mortality. Guidelines lack specific reference values for HR recovery. We defined normal values and studied blunted HR response and recovery and mortality risk.

METHODS AND RESULTS

We included 9917 subjects (45% females) aged 18-85 years who performed a cycle exercise test. We defined normal values for peak HR, HR reserve, and HR recovery at 1 and 2 min (HRR1 and HRR2) based on individuals apparently healthy (N = 2242). Associations between blunted HR indices (<5th percentile) and mortality over a median follow-up of 8.6 years were analysed using Cox regression and competing risk analysis. All HR indices were age-dependent and independent predictors of all-cause and cardiovascular (CV) mortality. The 5th percentiles of HR reserve, HRR1, and HRR2 correlated weakly with existing reference values. Heart rate recovery variables were the strongest predictors of all-cause mortality in both the overall population [HRR1, hazard ratio 1.70 (95% confidence interval, 1.49-1.94), and HRR2, 1.57 (1.37-1.79)] and in subjects with normal exercise capacity [HRR1, 1.96 (1.61-2.39), and HRR2, 1.76 (1.46-2.12)]. Combining HR indices appeared to increase the risk of all-cause [HRR1 and HRR2, 1.96 (1.68-2.29), and peak HR and HRR1, 1.87 (1.56-2.23)] and CV mortality, although no specific combination was superior for predicting CV mortality.

CONCLUSION

All HR indices were age-dependent and associated with all-cause and CV mortality. Blunted HR recovery variables were the strongest predictors of all-cause mortality, even in subjects with normal exercise capacity. Combined blunted HR indices appeared to add prognostic value.

Association of Postexercise Vagal Dysfunction With Protein-Energy Wasting and Noncardiovascular Outcomes in Patients Receiving Hemodialysis: A Retrospective Cohort Study

OBJECTIVE

Postexercise vagal dysfunction is linked to noncardiovascular mortality in hemodialysis patients, but the mechanism is unknown. This study aimed to determine the association of cardiovagal neuropathy with systemic inflammation, protein-energy wasting, and noncardiovascular hospitalization.

METHODS

This 2-center retrospective cohort study analyzed data from 280 hemodialysis patients who underwent exercise test. Patients were assessed for heart rate (HR) recovery (bpm) for 1 minute after exercise, a marker of vagal function, and were divided into 3 categories (Low: ≤ 6, Mid: 7-11, High: ≥ 12 bpm). We followed 1-year changes in the systemic inflammation-based prognostic score (Glasgow Prognostic Score [GPS]), body weight, and creatinine generation rate (CGR), an indicator of muscle mass, as well as 2-year hospitalization.

RESULTS

The HR recovery category was associated with serum C-reactive protein and albumin levels and GPS. After 1 year, the low HR recovery category was associated with worsening in GPS (low, 0 [0-0.5]; mid, 0 [0-1]; high, 0 [0-0]), weight (low, 100.0 [96.1-102.5]; mid, 101.3 [98.9-105.0]; high, 100.5 [98.2-102.9]%), and CGR (low, 97.0 [88.5-111.4]; mid, 110.2 [90.9-124.8]; high, 106.2 [95.5-115.5]%), and the correlations with GPS and CGR remained consistent after adjusting for confounders such as exercise capacity and hospitalization during the follow-up period. There were 117 patients hospitalized. Compared to the high HR recovery category, the mid (hazard ratio: 1.8, 95% confidence interval [CI]: 1.1-3.1, P = .02) and low (hazard ratio: 2.4, 95% CI: 1.5-4.0, P = .001) categories were independently associated with an increased risk of all-cause hospitalization. For noncardiovascular disease hospitalization, the low HR recovery category was independently associated with increased risk of hospitalization (hazard ratio: 2.1, 95% CI: 1.2-3.7, P = .007).

CONCLUSIONS

Vagal neuropathy in this population can contribute to adverse outcomes associated with systemic inflammation and protein-energy wasting.

Post-exercise heart rate variability recovery after 800-m endurance run load among Cameroonian adolescent's males

The 800-m (m) run is part of Physical Education classes in Cameroon, after which arrhythmias may occur during recovery. Hence, this study aimed at determining relationship between 800-m run loads on cardiac autonomic recovery among school adolescents. Forty-two male adolescents (aged [17 ​± ​1] years) performed 800-m. Post-exercise heart rate variability (HRV) was recorded during 5-min (min) (HRV5-min) and 15-min (HRV15-min) in time: Standard deviation of normal to normal (SDNN); Root mean square of successive differences (RMSSD) and frequency domain (LH: Low frequency, HF: High frequency, TP: Total power). Rating of Perceived Exertion (RPE) and blood lactate concentration (BLa) were measured after exercise. In HRV5-min, RPE was associated with SDNN (r ​= ​-0.44, p ​< ​0.01) and RMSSD (r ​= ​-0.38, p ​< ​0.05). BLa was correlated with SDNN (r ​= ​-0.38, p ​< ​0.05) and RMSSD (r ​= ​-0.56, p ​< ​0.001) in the time-domain, LF (r ​= ​-0.64, p ​< ​0.001), HF (r ​= ​-0.58, p ​< ​0.001) and TP (r ​= ​-0.61, p ​< ​0.001) in frequency-domain. Moreover, RPE was correlated with LF (r ​= ​-0.44, p ​< ​0.01), TP (r ​= ​-0.49, p ​< ​0.01) while exercise duration with HF (r ​= ​-0.38, p ​< ​0.05). In HRV15-min, BLa was correlated with RMSSD (r ​= ​-0.53, p ​< ​0.001) and SDNN (r ​= ​-0.68, p ​< ​0.001). RPE was negatively correlated SDNN (r ​= ​-0.53, p ​< ​0.01) and RMSSD (r ​= ​-0.44, p ​< ​0.01). BLa was associated with HF (r ​= ​-0.55, p ​< ​0.001), TP (r ​= ​-0.50, p ​< ​0.01) and RPE with LF (r ​= ​-0.51, p ​< ​0.01), HF (r ​= ​-0.50, p ​< ​0.01), TP (r ​= ​-0.49, p ​< ​0.01). In addition, exercise duration was negatively linked to HF (r ​= ​-0.36, p ​< ​0.05). This study outlined that in untrained adolescents an increase of 800-m loads is associated with a slow vagal indexes of HRV during the recovery.

The incremental significance of heart rate recovery as a predictor during exercise-stress myocardial perfusion SPECT imaging in individuals with suspected coronary artery disease

Background

Major adverse cardiac events (MACE) are more likely to occur when abnormal heart rate recovery (HRR). This study aimed to assess the incremental predictive significance of HRR over exercise stress myocardial perfusion single-photon emission computed tomography (MPS) results for MACE in individuals with suspected coronary artery disease (CAD).

Methods

Between January 2014 and December 2017, we continually gathered data on 595 patients with suspected CAD who received cycling exercise stress MPS. HRR at 1, 2, 3, and 4 min were used as study variables to obtain the optimal cut-off values of HRR for MACE. The difference between the peak heart rate achieved during exercise and the heart rate at 1, 2, 3, and 4 min was used to calculate the HRR, as shown in HRR3. Heart rate variations between two locations in time, such as HRR_{2 min-1 min}, were used to establish the slope of HRR. All patients were followed for a minimum of 4 years, with MACE as the follow-up goal. The associations between HRR and MACE were assessed using Cox proportional hazards analyses.

Results

Patients with MACE were older (P = 0.001), and they also had higher rates of hypertension, dyslipidemia, diabetes, abnormal MPS findings (SSS ≥ 5%), medication history (all P < 0.001), and lower HRR values (all P < 0.01). Patients with and without MACE did not significantly vary in their HRR_{4 min-3 min}. The optimal cut-off of HRR1, 2, and 3 combined with SSS can stratify the risk of MACE in people with suspected CAD (all P < 0.001). HRR 1, 2, and 3 and its slope were linked to MACE in multivariate analysis, where HRR3 was the most significant risk predictor. With a global X² increase from 101 to 126 (P < 0.0001), HRR3 demonstrated the greatest improvement in the model's predictive capacity, incorporating clinical data and MPS outcomes.

Conclusions

HRR at 3 min has a more excellent incremental prognostic value for predicting MACE in patients with suspected CAD following cycling exercise stress MPS. Therefore, incorporating HRR at 3 min into known predictive models may further improve the risk stratification of the patients.

Validation of StepTest4all for Assessing Cardiovascular Capacity in Young Adults

BACKGROUND

Cardiovascular capacity, expressed as maximal oxygen uptake (VO_2max), is a strong predictor of health and fitness and is considered a key measure of physiological function in the healthy adult population. The purpose of this study was to validate a specific step test (StepTest4all) as an adequate procedure to estimate cardiovascular capacity in young adults.

METHODS

The sample was composed of 56 participants, including 19 women (aged 21.05 ± 2.39 years, body mass = 57.50 ± 6.64 kg, height = 1.62 ± 0.05 m, body mass index = 22.00 ± 2.92 kg/m²) and 37 men (aged 22.05 ± 3.14 years, body mass = 72.50 ± 7.73 kg, height = 1.76 ± 0.07 m, body mass index = 23.34 ± 2.17 kg/m²). Participants were included in one of the following groups: (i) the group used to predict the VO_2max, and (ii) the group used to validate the prediction model. All participants performed the StepTest4all protocol. The step height and the intensity of the effort was determined individually. Heart rate and oxygen uptake were measured continuously during rest, effort, and recovery phases. The validation process included the following three stages: (i) mean data comparison, (ii) simple linear regression, and (iii) Bland-Altman analysis.

RESULTS

The linear regression retained, as significant predictors of the VO_2max, sex (p < 0.001) and heart rate recovery for one minute (p = 0.003). The prediction equation revealed a high relationship between measurements (R² = 63.0%, SEE = 5.58). The validation procedure revealed non-significant differences (p > 0.05) between the measured and estimated maximal oxygen uptake, high relationship (R² = 63.3%), and high agreement with Bland-Altman plots. Thus, VO_2max can be estimated with the formula: VO_2max = 22 + 0.3 · (HRR_1min) + 12 · (sex), where HRR_1min is the magnitude of the HR decrease (bpm) in one minute immediately after the step was stopped, and sex: men = 1, women = 0.

CONCLUSIONS

The StepTest4all is an adequate procedure to estimate cardiovascular capacity, expressed as VO_2max, in young adults. In addition, it is possible to determine the qualitative level of cardiovascular capacity from the heart rate recovery for one minute, more specifically, poor: <20, moderate: 20 to 34, good: 35 to 49, and excellent: ≥50. This procedure has the benefit of being simple to apply and can be used by everyone, even at home, without specialist supervision.

Decrease of heart rate variability during exercise: An index of cardiorespiratory fitness

The present study proposes to measure and quantify the heart rate variability (HRV) changes during effort as a function of the heart rate and to test the capacity of the produced indices to predict cardiorespiratory fitness measures. Therefore, the beat-to-beat cardiac time interval series of 18 adolescent athletes (15.2 ± 2.0 years) measured during maximal graded effort test were detrended using a dynamical first-order differential equation model. HRV was then calculated as the standard deviation of the detrended RR intervals (SDRR) within successive windows of one minute. The variation of this measure of HRV during exercise is properly fitted by an exponential decrease of the heart rate: the SDRR is divided by 2 every increase of heart rate of 20 beats/min. The HR increase necessary to divide by 2 the HRV is linearly inversely correlated with the maximum oxygen consumption (r = -0.60, p = 0.006), the maximal aerobic power (r = -0.62, p = 0.006), and, to a lesser extent, to the power at the ventilatory thresholds (r = -0.53, p = 0.02 and r = -0.47, p = 0.05 for the first and second threshold). It indicates that the decrease of the HRV when the heart rate increases is faster among athletes with better fitness. This analysis, based only on cardiac measurements, provides a promising tool for the study of cardiac measurements generated by portable devices.

Cardiovascular Autonomic Function Changes and Predictors During a 2-Year Physical Activity Program in Rheumatoid Arthritis: A PARA 2010 Substudy

Background: Chronic inflammation leads to autonomic dysfunction, which may contribute to the increased risk of cardiovascular diseases (CVD) in patients with rheumatoid arthritis (RA). Exercise is known to restore autonomic nervous system (ANS) activity and particularly its parasympathetic component. A practical clinical tool to assess autonomic function, and in particular parasympathetic tone, is heart rate recovery (HRR). The aim of this substudy from the prospective PARA 2010 study was to determine changes in HRR post-maximal exercise electrocardiogram (ECG) after a 2-year physical activity program and to determine the main predictive factors associated with effects on HRR in RA. Methods: Twenty-five participants performed physiotherapist-guided aerobic and muscle-strengthening exercises for 1 year and were instructed to continue the unsupervised physical activity program autonomously in the next year. All participants were examined at baseline and at years 1 and 2 with a maximal exercise ECG on a cycle ergometer. HRR was measured at 1, 2, 3, 4, and 5 min following peak heart rate during exercise. Machine-learning algorithms with the elastic net linear regression models were performed to predict changes in HRR1 and HRR2 at 1 year and 2 years of the PARA program. Results: Mean age was 60 years, range of 41-73 years (88% women). Both HRR1 and HRR2 increased significantly from baseline to year 1 with guided physical activity and decreased significantly from year 1 to year 2 with unsupervised physical activity. Blood pressure response to exercise, low BMI, and muscular strength were the best predictors of HRR1/HRR2 increase during the first year and HRR1/HRR2 decrease during the second year of the PARA program. Conclusion: ANS activity in RA assessed by HRR was improved by guided physical activity, and machine learning allowed to identify predictors of the HRR response at the different time points. HRR could be a relevant marker of the effectiveness of physical activity recommended in patients with RA at high risk of CVD. Very inactive and/or high CVD risk RA patients may get substantial benefits from a physical activity program.

Biochemical and Hematological Relationship with the Evaluation of Autonomic Dysfunction by Heart Rate Recovery in Patients with Asthma and Type 2 Diabetes

There are several methods to assess the function of the autonomic nervous system. Among them, heart rate recovery (HRR) is an accepted, easy, low-cost technique. Different pathological conditions have been related to the development of autonomic dysfunction. Our study aimed to evaluate the relationship between HRR and HRR-derived parameters in ambulatory patients with asthma or type 2 diabetes followed at the National Institutes of Health in Mexico City. A total of 78 participants, 50 women and, 28 men were enrolled; anthropometric, respiratory evaluations, and fasting blood samples were taken before participants performed a 6-min walking test (6MWT). Abnormal HRR was defined as a drop of ≤8 and ≤11 beats/min at 1 or 2 min and correlated negatively with basal oxygen saturation at 1 min. Heart rate at 1 min, correlated negatively with final oxygen saturation (p < 0.01). Statistically significant negative correlations were also observed between red cell count and white blood cell count and HOMA-IR with a p < 0.01. Since discrete hematological but significant changes correlated with HRR and HRR-derived parameters, we consider that these measures are helpful in clinical settings to identify subclinical autonomic dysfunction that permits us to prevent or anticipate chronic and fatal clinical outcomes.

The movement-to-music (M2M) study: study protocol for a randomized controlled efficacy trial examining a rhythmic teleexercise intervention for people with physical disabilities

BACKGROUND

People with physical disabilities need exercise routines that are enjoyable, readily available in the home, adapted to their functional level, and eliminate common barriers to exercise participation related to transportation and time commitment. The purpose of the movement-to-music (M2M) study is to address these issues by establishing a remotely delivered, rhythmic exercise program for people with physical disabilities.

METHODS

The study is a two-arm randomized controlled efficacy trial examining a 12-week remotely delivered M2M intervention (eM2M) in 108 people with physical disabilities. The primary outcomes are changes in cardiorespiratory fitness and muscle strength at post 12-week intervention.

DISCUSSION

The eM2M study will enhance our understanding of an alternative intervention design and delivery mode that removes common barriers to exercise participation experienced by people with physical disabilities. The eM2M intervention may be an alternative option for people with physical disabilities to obtain regular exercise, especially during a pandemic when exercising in indoor facilities may be problematic.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03797378. Registered on January 9, 2019, with the trial name "Movement-to-Music: Lakeshore Examination of Activity, Disability, and Exercise Response Study (M2M LEADERS)".

Smart wearable devices in cardiovascular care: where we are and how to move forward

Technological innovations reach deeply into our daily lives and an emerging trend supports the use of commercial smart wearable devices to manage health. In the era of remote, decentralized and increasingly personalized patient care, catalysed by the COVID-19 pandemic, the cardiovascular community must familiarize itself with the wearable technologies on the market and their wide range of clinical applications. In this Review, we highlight the basic engineering principles of common wearable sensors and where they can be error-prone. We also examine the role of these devices in the remote screening and diagnosis of common cardiovascular diseases, such as arrhythmias, and in the management of patients with established cardiovascular conditions, for example, heart failure. To date, challenges such as device accuracy, clinical validity, a lack of standardized regulatory policies and concerns for patient privacy are still hindering the widespread adoption of smart wearable technologies in clinical practice. We present several recommendations to navigate these challenges and propose a simple and practical 'ABCD' guide for clinicians, personalized to their specific practice needs, to accelerate the integration of these devices into the clinical workflow for optimal patient care.

Peak Systolic Blood Pressure During the Exercise Test: Reference Values by Sex and Age and Association With Mortality

[Figure: see text].

Heart rate recovery is useful for evaluating the recovery of exercise tolerance in patients with heart failure and atrial fibrillation

This study aimed to examine the factors that contribute to improvement of exercise tolerance in patients with heart failure (HF) and atrial fibrillation (AF) following cardiac rehabilitation. Our hypothesis is that parasympathetic values are important for recovering exercise tolerance in those patients. We included 84 consecutive patients with HF and AF (mean age: 69 ± 15 years, 80% men). All of the patients underwent a cardiopulmonary exercise test and had pre and post 5 month cardiac rehabilitation assessed. After 155 ± 11 days and 44 ± 8 sessions, 73 patients (86%) showed an increase in peak oxygen uptake (VO₂) and VO₂ at the anaerobic threshold. In univariate linear regression analysis, the % change in heart rate recovery, plasma B-type natriuretic peptide levels, resting heart rate, and the minute ventilation /carbon dioxide output slope were significantly related to that of peak VO₂ (p < 0.01, p = 0.03, p = 0.02, p < 0.01, respectively). Stepwise multivariate linear regression analysis showed that the % change in heart rate recovery was independently related to that of peak VO₂ (p < 0.05). Our results suggest that heart rate recovery is closely associated with recovery of exercise tolerance in patients with HF and AF after CR.

Comparison of heart rate response and heart rate recovery after step test among smoker and non-smoker athletes

BACKGROUND

Exercise performance depend on the ability of the cardiovascular system to respond to a wide range of metabolic demands and physical exertion.

OBJECTIVES

To investigate the habitual smoking effects in heart rate response and heart rate recovery after step test in athletes.

METHODS

Seventy-eight physically healthy active athletes (45 non-smokers and 33 smokers) aging 27±8 years old, participated in this study. All participants completed the International Physical Activity Questionnaire and performed the six-minute step test. Cardiovascular parameters such (resting heart rate, peak heart rate, heart rate at 1 min after testing, heart rate recovery, recovery time, blood pressure at rest, and post-testing blood pressure) were recorded.

RESULTS

Smoker-athletes had higher resting heart rate (76 ± 9bpm vs. 72 ± 10bpm, p<0.05), maximum heart rate (154 ± 18bpm vs. 147 ± 17bpm, p<0.05) and recovery time (7min 25sec ± 6min 31sec vs. 4min 21sec ± 4min 30sec, p<0.05) than non-smoker athletes. Scores from the IPAQ were approximately the same (M=7927 ± 10303, M= 6380 ± 4539, p<0.05).

CONCLUSION

Smoking was found to affect athletes' cardiovascular fitness. The change of the athletes' heart rate recovery and recovery time contributes to the adaptation of cardiovascular function in training requirements.

Post-exercise heart rate recovery and its speed are associated with cardiac autonomic responsiveness following orthostatic stress test in men

Objective: The present study sought to expand upon prior investigations of the relationship between the post-exercise heart rate recovery (HRR) and the cardiac autonomic responsiveness after orthostatic stress test.Method: HRR at the 1st, 3rd, and 5th min after maximal exercise test were correlated with relative change (Δ%) of time-domain (CV, pNN50, and rMSSD) and frequency-domain (TP, LF, HF, and LF/HF ratio) indices of heart rate variability (HRV) after active orthostatic test in 46 healthy men. Statistical analysis employed non-parametric tests with a p-value set at 5%.Results: HRR at 1st min correlated with Δ%pNN50 (r_s:0.36 - p = .02). In the 3rd and 5th min, these measures correlated with Δ%pNN50, Δ%rMSSD, Δ%CV, Δ%TP, and Δ%HF indices (r_s:0.33, 0.59 - p ≤ .05). Coefficient of HRR at the 1st min correlated with Δ%pNN50, Δ%rMSSD, and Δ%HF (r_s:0.28, 0.45 - p ≤ .05). The 3rd and 5th min showed correlation with Δ%pNN50, Δ%rMSSD, Δ%HF, Δ%CV, and Δ%TP (r_s:0.37, 0.64 - p ≤ .05). No correlation was found with indices combined sympathetic-parasympathetic modulation and HRR. After the sample was divided into high and low parasympathetic responsiveness subgroups after the orthostatic test, faster HRR was associated with the degree of parasympathetic responsiveness (reduction) following postural change (p ≤ .05).Conclusion: HRR throughout the 1st to 5th min is positively correlated with parasympathetic responsiveness and overall cardiac autonomic modulation of HRV after the orthostatic stress test, and faster HRR is positively correlated with the relative degree of parasympathetic responsiveness after the active postural change at rest in healthy men.

The impact of delayed heart rate recovery on prevalent hypertension

Objectives: Delayed heart rate recovery (HRR) is considered an indicator of autonomic nervous dysfunction, which is a primary pathological mechanism of hypertension. The present study aimed to explore the independent association between delayed HRR and prevalent hypertension.Methods: In this cross-sectional study, 314 inpatients were recruited between January 2018 and December 2019. HRR was defined as the peak heart rate during exercise minus the 2^nd-minute heart rate after exercise in the treadmill exercise test.Results: The mean HRR in the hypertension group was lower than that in the non-hypertension group (41 bpm vs. 46 bpm; P < 0.001). After full adjustment, each standard deviation increase in HRR was associated with a 35% decrease in the risk of prevalent hypertension (OR: 0.65, 95% CI: 0.48-0.87; P = 0.004). When the HRR was divided into quartiles, the risk in the top quartile was 26% of that in the bottom quartile (OR: 0.26, 95% CI: 0.12-0.56; P = 0.001). Furthermore, smooth curve fitting showed that the risk of prevalent hypertension decreased linearly with the increase in HRR.Conclusion: Delayed HRR was independently associated with prevalent hypertension. The association was linear and robust over the entire range of HRR. The present study suggested that delayed HRR could be used to optimize hypertension risk stratification.

The alpha-melanocyte stimulating hormone is related to heart rate during exercise recovery

Alpha-melanocyte-stimulating hormone (alpha-MSH) is a part of the hormonal stress system with proven cardiovascular effects. Heart rate recovery (HRR) following exercise is strongly correlated to overall fitness and future adverse cardiovascular events. The current study examined the predictive value of alpha-MSH for HRR following exercise testing.Cardiopulmonary exercise testing (CPET) on a treadmill was used to measure HR and oxygen consumption (V̇O2) in 16 elite male wrestlers (W), 21 water polo player (WP) and 20 sedentary subjects (C) matched for age. Plasma levels of alpha-MSH were measured by radioimmunoassay technique in four phases of CPET: 1) 10 min pre-CPET at rest; 2) at the initation of CPET; 3) at peak CPET; and 4) at the third minute of recovery. The WP group had significantly higher HRR compared to than W and C groups, who did not have significantly different values. Significant difference in alpha-MSH measurements and patterns during CPET between groups was not observed (p > 0.05). When combining all three groups, we observed a significant correlation between V̇O2 recovery and alpha-MSH recovery/peak (r = -0.3, p = 0.022). HRR and ΔHRR/peak significantly correlated with alpha-MSH at all four measurment points (r = -0.4; p < 0.01 for all). On multiple regression analysis, which included anthropometric and hormonal measures, the best independent predictor of HRR and ΔHRR/peak was alpha-MSH during recovery (B = -1.0, -0.5; SE = 0.3, 0.1; CI = -1.5 to -0.4, -0.7 to -0.2; p = 0.001 respectively). In conclusion, alpha-MSH measured during exercise recovery holds predictive value for HRR and ΔHRR/peak, suggesting a contributing role to integrative regulation of overall cardiopulmonary performance.

CONDENSED ABSTRACT

Present study examined the predictive value of alpha-melanocyte stimulating hormone (alpha-MSH) for heart rate recovery (HRR) in elite male wrestlers, water polo players and sedentary subjects matched for age. Alpha-MSH measured during exercise recovery holds predictive value for HRR and ΔHRR/peak, suggesting a contributing role to integrative regulation of overall cardiopulmonary performance.

Combination of low blood pressure response, low exercise capacity and slow heart rate recovery during an exercise test significantly increases mortality risk

Aims: We investigated the combination of low systolic blood pressure (SBP) response, low exercise capacity (EC) and slow heart rate recovery (HRR) during an exercise test in mortality prediction.Patients and methods: Our population consisted of 3456 patients from the Finnish Cardiovascular Study. A failure of SBP to increase >42 mmHg was defined as a low response. Low EC was defined as  < 8 metabolic equivalents. 1-minute HRR ≤18 bpm from maximum was defined as slow HRR.Results: During a median follow up of 10.0 years, 537 participants died. Reduced SBP response, low EC and slow HRR were independent predictors of all-cause and CV mortality (p < .001 for all). Patients with reduced SBP response, low EC and slow HRR had a very high mortality rate of 42.1% during follow up compared to only 4.5% of the patients without any of these risk factors. The hazard ratios for all-cause mortality in patients with one, two or three of the studied risk factors were 3.2, 6.0, and 10.6, respectively (p < .001 for all).Conclusion: The combination of reduced SBP response, low exercise capacity, and reduced HRR in an exercise test is associated with very high mortality and can be used in risk stratification.Key messagesThe combination of low blood pressure response, low exercise capacity and slow heart rate recovery in an exercise test is able to identify a group of patients in a very high mortality risk.These parameters are easily derived from an exercise test.All parameters are commonly available in clinical practice.

Association of postexercise heart rate recovery with body composition in healthy male adults: Findings from Pakistan

Background

This study investigated the effect of body mass index (BMI) and body fat ratio with postexercise heart rate recovery (HRR) after 2 minutes of rest.

Methods

Sixty‐four healthy males aged between 25 and 55 years participated in the study. BMI, body fat ratio, waist circumference, and physical activity were recorded. Peak heart rate after exercise and HRR after 2 min of rest were obtained.

Results

Mean age of participants was 35.53 ± 6.57. Mean BMI and HRR were 25.06 ± 4.62 and 26.07 ± 7.43, respectively. BMI and body fat ratio had significant negative correlation with HRR with r values of −.833 and −.877, respectively (p < .001*). Linear regression showed BMI and body fat ratio with significant coefficient of −0.426 (p = .04*) and −0.627 (p < .001*) with HRR, respectively. Participants with BMI ˂ 25 had higher HRR in comparison to participants with BMI ≥ 25 (p < .001*). Participants with body fat ratio of ˂25 had significantly higher HRR of 35.9 ± 3.98 in comparison to participants with body fat ratio ≥ 25 (p = <.001*).

Conclusion

Body mass index and body fat ratio are strong predictors of HRR in Pakistani healthy male adults, suggesting a strong link between metabolic risk factors and impaired autonomic nervous system.

Effect of Cardiorespiratory Fitness on Co-Morbidities and Mortality in Never, Past, and Current Smokers

Smoking is a strong risk factor for cardiovascular (CV) disease and mortality, but quitting may cause weight gain and increase the risk of co-morbidities. Our aim was to investigate the effect of smoking and exercise on weight-associated co-morbidities and mortality. We included Minnesota residents without baseline CV disease who underwent exercise testing from 1993 to 2010. Mortality was determined from Mayo Clinic records and Minnesota Death Index. Total, CV and cancer mortality by smoking status and cardiorespiratory fitness (CRF): (1) <80%, (2) 80% to 99%, (3) ≥100%. Differences were tested using logistic and Cox regression adjusting for age and gender. A total of 21,981 patients (7,090 past, 2,464 current smokers) were included. Past smokers had more obesity, hypertension, diabetes, and low CRF compared with never smokers. Current smokers did not show increased risk factor prevalence compared with never smokers but had higher rates of low CRF. There were 1,749 deaths; mean follow-up was 12 ± 5 years. Mortality was only slightly increased in past versus never smokers (Hazard Ratio: 1.2; 95% confidence interval 1.12 to 1.38) but was much higher in current smokers (Hazard Ratio 2.4; 95% confidence interval 2.05 to 2.80). Mortality in never, past, and current smokers was inversely related to CRF level. In conclusion, past smokers showed higher rates of co-morbidities and low CRF, but mortality was only mildly increased versus never smokers, whereas current smokers carried a high mortality risk. Our data suggest that quitting smoking is beneficial despite the increased co-morbidities. Exercise may potentially mitigate the risk of co-morbidities and death in those who quit smoking.