Associations of Sedentary Time with Heart Rate and Heart Rate Variability in Adults: A Systematic Review and Meta-Analysis of Observational Studies

Study protocol and rationale of "the UP project": evaluating the effectiveness of active breaks on health indicators in desk-based workers

Background

Excessive sedentary time has been negatively associated with several health outcomes, and physical activity alone does not seem to fully counteract these consequences. This panorama emphasizes the essential of sedentary time interruption programs. "The Up Project" seeks to assess the effectiveness of two interventions, one incorporating active breaks led by a professional and the other utilizing a computer application (self-led), of both equivalent duration and intensity. These interventions will be compared with a control group to evaluate their impact on physical activity levels, sedentary time, stress perception, occupational pain, and cardiometabolic risk factors among office workers.

Methods

This quasi-experimental study includes 60 desk-based workers from universities and educational institutes in Valparaiso, Chile, assigned to three groups: (a) booster breaks led by professionals, (b) computer prompts that are unled, and (c) a control group. The intervention protocol for both experimental groups will last 12 weeks (only weekdays). The following measurements will be performed at baseline and post-intervention: cardiometabolic risk based on body composition (fat mass, fat-free mass, and bone mass evaluated by DXA), waist circumference, blood pressure, resting heart rate, and handgrip strength. Physical activity and sedentary time will be self-reported and device-based assessed using accelerometry. Questionnaires will be used to determine the perception of stress and occupational pain.

Discussion

Governments worldwide are addressing health issues associated with sedentary behavior, particularly concerning individuals highly exposed to it, such as desk-based workers. Despite implementing certain strategies, there remains a noticeable gap in comprehensive research comparing diverse protocols. For instance, studies that contrast the outcomes of interventions led by professionals with those prompted by computers are scarce. This ongoing project is expected to contribute to evidence-based interventions targeting reduced perceived stress levels and enhancing desk-based employees' mental and physical well-being. The implications of these findings could have the capacity to lay the groundwork for future public health initiatives and government-funded programs.

Physical activity, residential greenness, and cardiac autonomic function

PURPOSE

This population-based study examines the associations between physical activity (PA), residential environmental greenness, and cardiac health measured by resting short-term heart rate variability (HRV).

METHODS

Residential greenness of a birth cohort sample (n = 5433) at 46 years was measured with normalized difference vegetation index (NDVI) by fixing a 1 km buffer around each participant's home. Daily light PA (LPA), moderate PA (MPA), vigorous PA (VPA), and the combination of both (MVPA) were measured using a wrist-worn accelerometer for 14 days. Resting HRV was measured with a heart rate monitor, and generalized additive modeling (GAM) was used to examine the association between PA, NDVI, and resting HRV.

RESULTS

In nongreen areas, men had less PA at all intensity levels compared to men in green areas. Women had more LPA and total PA and less MPA, MVPA, and VPA in green residential areas compared to nongreen areas. In green residential areas, men had more MPA, MVPA, and VPA than women, whereas women had more LPA than men. GAM showed positive linear associations between LPA, MVPA and HRV in all models.

CONCLUSIONS

Higher LPA and MVPA were significantly associated with increased HRV, irrespective of residential greenness. Greenness was positively associated with PA at all intensity levels in men, whereas in women, a positive association was found for LPA and total PA. A positive relationship of PA with resting HRV and greenness with PA was found. Residential greenness for promoting PA and heart health in adults should be considered in city planning.

Higher habitual lying time is inversely associated with vagal-related heart rate variability outcomes in younger adults

Heart rate variability (HRV) is a well-established noninvasive marker of autonomic cardiac control. We test whether time spent sitting (negatively) versus lying (positively) influences vagal HRV outcomes. HRV (10 min supine electrocardiogram) and free-living postures (dual-accelerometer configuration, 7 days) were measured in 31 young healthy adults (15♀, age: 23 ± 3 years). Habitual lying (66 ± 61 min/day), but not sitting time (558 ± 109 min/day), total sedentary time (623 ± 132 min/day), nor step counts (10 752 ± 3200 steps/day; all, p > 0.090), was associated with root mean square of successive cardiac interval differences (ρ = -0.409, p = 0.022) and normalized high-frequency HRV (ρ = -0.361, p = 0.046). These findings document a paradoxical negative impact of waking lying time on cardioautonomic function.   Take home message Using a multi-accelerometer configuration, we demonstrated that more habitual waking time lying, but not sitting or total sedentary time, was associated with worse vagally mediated cardiac control.

Associations between physical activity and autonomic function during deep breathing test: the Swedish CArdioPulmonary bioImage Study (SCAPIS)

PURPOSE

The deep breathing test (DBT) is a sensitive test of cardiovagal function. The aim of this study was to explore associations between physical activity and sedentary time, measured by accelerometer, and autonomic function, using DBT.

METHODS

In the Swedish Cardio-Pulmonary bioImage Study, men and women aged 50-64 were randomly invited from the general population. A total of 4325 subjects who underwent DBT and assessment of physical activity and sedentary time by accelerometery were included. ECG files from 1-min DBT were used to calculate measures of respiratory sinus arrhythmia [RSA; expiration-inspiration (E-I) difference and E/I ratio], heart rate variability [HRV; root mean square of successive differences (RMSSD), standard deviation of heart rates and mean circular resultant]. Low RSA and HRV was defined as the lowest 10% in the population.

RESULTS

For accelerometer-assessed physical activity, there were significant associations between high percentage of sedentary time and low E/I (p < 0.01), and low RMSSD (p < 0.01) in an age- and sex-adjusted model, and between percentage of sedentary time and low RMSSD (p = 0.04) in a risk factor-adjusted model. Low RMSSD was less common in those with a high percentage of moderate to vigorous physical activity (p = 0.04, after risk-factor adjustment). These associations became non-significant when further adjusting for heart rate.

CONCLUSION

We report associations between degree of physical activity and indices of autonomic dysfunction in a large population. The relationships were no longer significant after adjustments for heart rate, indicating that the relationship between physical activity and cardiovagal function partly is accounted for by reduced heart rate.

Paradoxical Associations of Occupational and Nonoccupational Sedentary Behavior With Cardiovascular Disease Risk Measures in Desk Workers

OBJECTIVES

We assessed sedentary behavior (SB) patterns and examined its associations, by domain, with cardiovascular disease (CVD) risk measures in desk workers ( N = 273).

METHODS

Sedentary behavior was measured by activPAL3 and partitioned into occupational and nonoccupational SB. Cardiovascular disease risk measures included blood pressure, pulse wave velocity, heart rate, and heart rate variability. Paired t tests evaluated patterns of SB across domains. Linear regressions estimated associations of occupational and nonoccupational SB with CVD risk measures.

RESULTS

Participants spent 69% of their time in SB; higher proportions were accumulated during occupational versus nonoccupational time. Higher all-domain SB was only associated with higher pulse wave velocity. Paradoxically, greater nonoccupational SB unfavorably associated with CVD risk measures, while higher occupational SB favorably correlated to CVD risk measures.

CONCLUSIONS

Observed paradoxical associations suggest that domain should be considered in efforts to improve cardiovascular health by reducing SB.

A Comparative Cross-Sectional Study of Cardiac Autonomic Status by Five Minute Heart Rate Variability among Type 2 Diabetics, Hypertensives and Normotensive-Nondiabetics

Background

Diabetes and hypertension are known to co-exist frequently as adverse cardiovascular risk factors. Both can produce cardiac autonomic neuropathythat can be measured by ECG RR interval-based heart rate variability (HRV). We compared 5 minutes HRV in four groups based on diabetes and hypertension.

Methodology

A cross sectional study was done on 203 participants divided into four groups- diabetics, hypertensives, diabetic-hypertensives and normotensive-nondiabetics. They were evaluated for current disease control and five minutes HRV was done in supine condition following standard protocols by Variowin HR Software. HRV parameters of time domain, frequency domain and Poincare plot were compared between groups and associated with gender, glycaemic control and blood pressure control. Statistical significance was set at p<0.05.

Results

Three diseasedgroups had mean age in mid-fifties, mean duration of disease > 6 years, comparable BMI, poor glycaemic and blood pressure control. As compared to normal groups, three diseased groups exhibit reduced HRV with respect to all three domains of HRV with varying statistical significance. Among diseased groups, HRV was associated with blood pressure control better than glycaemic control but not with gender. LF /HF ratio was the most consistent HRV parameter showing statistical significance in tests.

Conclusion

HRV is reduced in both diabetics more than hypertensives; related to blood pressure control more than glycaemic control. It points altered cardiac autonomic balance, and possibility of cardiovascular risk and early detection of it with timely intervention. It also calls for investigation of same for reinforcement of our observations and further exploration.

Temporal longitudinal associations of carotid-femoral pulse wave velocity and carotid intima-media thickness with resting heart rate and inflammation in youth

We examined the temporal longitudinal associations of carotid-femoral pulse wave velocity (cfPWV) and carotid intima-media thickness (cIMT) with the risk of elevated resting heart rate (RHR) and high-sensitivity C-reactive protein (hsCRP). We studied 3,862 adolescents, mean age 17.7 (SD 0.3 yr), followed-up for 7 yr until age 24.5 (0.7) yr, from the Avon Longitudinal Study of Parents and Children, UK. RHR, fasting plasma hsCRP, cfPWV, and cIMT were repeatedly assessed and analyzed using logistic regression, linear mixed-effect, and structural equation models adjusting for important covariates. Among 3,862 adolescents [2,143 (55.5%) female], 10% and 44% were at moderate-to-high risk of elevated RHR and hsCRP at 24.5 yr, respectively. Higher cfPWV at 17.7 yr was associated with elevated RHR risk at follow-up [odds-ratio (OR) 1.58 (CI 1.20-2.08); P = 0.001], whereas cIMT at 17.7 yr was associated with elevated hsCRP risk [OR 2.30 (1.18-4.46); P = 0.014] at follow-up, only among females. In mixed model, 7-yr progression in cfPWV was directly associated with 7-yr increase in RHR [effect-estimate 6 beats/min (1-11); P = 0.017] and hsCRP. cIMT progression was associated with 7-yr increase in RHR and hsCRP. In cross-lagged model, higher cfPWV at 17.7 yr was associated with higher RHR (β = 0.06, standard error = 3.85, P < 0.0001) at 24.5 yr but RHR at 17.7 yr was unassociated with cfPWV at 24.5 yr. Baseline cIMT or RHR was unassociated with either outcome at follow-up. Higher hsCRP at 17.7 yr was associated with higher cfPWV and cIMT at 24.5 yr. In conclusion, adolescent arterial stiffness but not cIMT appears to precede higher RHR in young adulthood, whereas elevated hsCRP in adolescence preceded higher cfPWV and cIMT.NEW & NOTEWORTHY Higher arterial stiffness but not carotid-intima media thickness in adolescence preceded higher resting heart rate in young adulthood, however, elevated high sensitivity C-reactive protein in adolescence preceded higher arterial stiffness and carotid intima-thickness in young adulthood in the temporal causal path. Low-grade inflammation during adolescence may be causally associated with the development of subclinical arteriosclerosis and atherosclerosis in young adulthood.

Prognostic value of resting heart rate in predicting undiagnosed diabetes in adults: Korean National Health and Nutrition Examination Survey 2008-2018

BACKGROUND AND AIM

Although resting heart rate (RHR) is associated with prevalence and incidence of diabetes, whether it is associated with undiagnosed diabetes is still unclear. We aimed to investigate whether the RHR is associated with the prevalence of undiagnosed diabetes in a large Korean national dataset.

METHODS AND RESULTS

The Korean National Health and Nutrition Examination Survey data from 2008 to 2018 were used. After screening, 51,637 participants were included in this study. The odds ratios and 95% confidence intervals (CIs) for undiagnosed diabetes were calculated using multivariable-adjusted logistic regression analyses. Analyses showed that participants with a RHR of ≥90 bpm showed a 4.00- (95% CI: 2.77-5.77) and 3.21-times (95% CI: 2.01-5.14) higher prevalence of undiagnosed diabetes for men and women, respectively, than those with a RHR of <60 bpm. The linear dose-response analyses showed that each 10-bpm increment in RHR was associated with a 1.39- (95% CI: 1.32-1.48) and 1.28-times (95% CI: 1.19-1.37) higher prevalence of undiagnosed diabetes for men and women, respectively. In the stratified analyses, the positive association between RHR and the prevalence of undiagnosed diabetes was tended to be stronger among those who were younger (age: <40 years) and lean (BMI: <23 kg/m²).

CONCLUSIONS

Elevated RHR was significantly associated with a higher prevalence of undiagnosed diabetes in Korean men and women, independent of demographic, lifestyle, and medical factors. Accordingly, the value of RHR as a clinical indicator and health marker, especially in reducing the prevalence of undiagnosed diabetes, is suggestible.

Correlation between physical activity, cardiorespiratory fitness and heart rate variability among young overweight adults

Objective

Cardiac autonomic function assessed by heart rate variability (HRV) is a non-invasive, quantitative, and reliable marker of measurement. An altered cardiac autonomic function among overweight individuals predisposes them to a greater risk of developing cardiovascular diseases. The present study aims to determine the correlation between physical activity, cardiorespiratory fitness and heart rate variability among young overweight adults.

Methods

A total of 45 participants (23 men and 22 women) were enrolled in the cross-sectional study with inclusion criteria as follows: aged between 18–30 years, body mass index (kg/m²) between 25–29.9 kg/m², and without any known or diagnosed medical condition. Physical activity level and cardiorespiratory fitness were measured using the Global Physical Activity Questionnaire and Bruce treadmill protocol test, respectively. Cardiac autonomic function was measured using a 5-min short-term heart rate variability recording. The time and frequency domain measures of HRV were used for analysis.

Results

The mean age of study participants was 22.53 ± 1.58 years and mean body mass index was 27.38 ± 1.51 kg/m2. Among young overweight adults, cardiorespiratory fitness and physical activity were not correlated with Root mean square of successive RR interval differences, Percentage of successive RR intervals that differ by more than 50 ms, and Ratio of LF [ms2]/HF [ms2].

Conclusion

The study found no correlation between physical activity and cardiorespiratory fitness with heart rate variability among young overweight individuals.