Effects of Exercise on the Resting Heart Rate: A Systematic Review and Meta-Analysis of Interventional Studies

Moderate-intensity constant or high-intensity interval training? Metabolic effects on candidates to undergo bariatric surgery

BACKGROUND & AIMS

Bariatric surgery is highly effective against obesity. Pre-surgical exercise programs are recommended to prepare the candidate physically and metabolically for surgery-related rapid weight loss. However, the ideal exercise prescription in this population is unknown. This study aimed to compare the metabolic effects of moderate-intensity constant (MICT) vs. a high-intensity interval training (HIIT) program in candidates to undergo bariatric surgery.

METHODS AND RESULTS

Twenty-five candidates (22 women) to undergo sleeve gastrectomy aged from 18 to 60 years old were recruited. At baseline, we measured body composition, physical activity levels, grip strength, and aerobic capacity. Further, we assessed metabolic function through glycemia and insulinemia (both fasting and after oral glucose tolerance test (OGTT)), homeostatic model assessment for insulin resistance (HOMA-IR), lipid profile, glycated haemoglobin (HbA1c), transaminases, fibroblast growth factor 21 (FGF21), growth differentiation factor 15 (GDF15), apelin, and adiponectin. Afterward, participants were randomized into MICT (n = 14) or HIIT (n = 11). Both training programs consisted of 10 sessions (2-3 times/week, 30 min per session) distributed during 4 weeks before the surgery. After this, all outcomes were measured again at the end of the training programs and 1 month after the surgery (follow-up). A mixed effect with Tukey's post-hoc analysis was performed to compare values at baseline vs. post-training vs. postsurgical follow-up. Both training programs increased aerobic capacity after training (p < 0.05), but only after MICT these changes were kept at follow-up (p < 0.05). However, only MICT decreased fat mass and increased total muscle mass and physical activity levels (p < 0.05). Metabolically, MICT decreased insulinemia after OGTT (p < 0.05), whereas HIIT increased adiponectin after training and GDF15 at follow-up (both p < 0.05).

CONCLUSIONS

Both MICT and HIIT conferred benefits in candidates to undergo bariatric surgery, however, several of those effects were program-specific, suggesting that exercise intensity should be considered when preparing these patients. Future studies should explore the potential benefits of prescribing MICT or HIIT in a customized fashion depending on a pretraining screening, along with possible summatory effects by combining these two exercise programs (MICT + HIIT).

CLINICAL TRIAL REGISTRATION

International Traditional Medicine Clinical Trial Registry, N° ISRCTN42273422.

Predicting sports performance of elite female football players through smart wearable measurement platform

Recent development of information technology and wearable devices has led to the analysis of multidimensional sports information and the enhancement of athletes' sports performance convenient and potentially more efficient. In this study, we present a novel data platform tailored for capturing athletes' cognitive, physiological, and body composition data. This platform incorporates diverse visualization modes, enabling athletes and coaches to access data seamlessly. Fourteen elite female football players (average age=20.6±1.3years; 3 forwards, 5 midfielders, 4 defenders, and 2 goalkeepers) were recruited from National Taiwan Normal University, Taiwan, as the primary observational group, and 12 female university students without regular sport/exercise habits (average age=21.6±1.3years) were recruited as control group. Through multidimensional data analysis, we identified significant differences in limb muscle mass and several cognitive function scores (e.g., reaction times of attention and working memory) between elite female football varsity team and general female university students. Furthermore, 1-month heart rate data obtained from wearable devices revealed a significant negative correlation between average heart rate median and cognitive function scores. Overall, this study demonstrates the potential of this platform as an efficient multidimensional data collection and analysis platform. Therefore, valuable insights between cognitive functions, physiological signals and body composition can be obtained via this multidimensional platform for facilitating sports performance.

Lumbar Paravertebral Muscle Pain Management Using Kinesitherapy and Electrotherapeutic Modalities

BACKGROUND

Low back pain is considered a public health problem internationally. Low back pain is a cause of disability that occurs in adolescents and causes negative effects in adults as well. The work environment and physical and psychosocial factors can influence the occurrence and evolution of low back pain.

METHODS

The purpose of this paper is to highlight the physiological and functional changes in young adults with painful conditions of the lumbar spine, after using exercise therapy. The study was of the longitudinal type and was carried out over a period 6 months in an outpatient setting. The rehabilitation treatment included electrotherapeutic modalities and kinesitherapy.

RESULTS

The results obtained when evaluating each parameter, for all moments, show statistically significant values in both groups. The results obtained regarding the relationship between the therapeutic modalities specific to rehabilitation medicine and low back pain are consistent with those reported in studies.

CONCLUSIONS

Depending on the clinical-functional status of each patient, kinesitherapy can accelerate the heart rate and increase the blood pressure and oxygen saturation of the arterial blood, values that can later return to their initial levels, especially through training.

Swimming with a head-mounted display: dual-task costs

Head-up displays (HUDs) have the potential to change work in operation environments by providing hands-free information to wearers. However, these benefits may be accompanied by trade-offs, primarily by increasing cognitive load due to dividing attention. Previous studies have attempted to understand the trade-offs of HUD usage; however, all of which were focused on land-based tasks. A gap in understanding exists when examining HUD use in aquatic environments as immersion introduces unique environmental and physiological factors that could affect multitasking. In this study, we investigated multitasking performance associated with swimming with a HUD. Eighteen participants completed three tasks: swimming only, a HUD-administered word recall task, and a dual-task combining both tasks. Results revealed significant dual-task interference in both tasks, though possibly less pronounced than in land-based tasks. These findings enhance not only help characterise dual-task performance, but also offer valuable insights for HUD design for aquatic settings.

Sleeping for One Week on a Temperature-Controlled Mattress Cover Improves Sleep and Cardiovascular Recovery

Body temperature should be tightly regulated for optimal sleep. However, various extrinsic and intrinsic factors can alter body temperature during sleep. In a free-living study, we examined how sleep and cardiovascular health metrics were affected by sleeping for one week with (Pod ON) vs. without (Pod OFF), an active temperature-controlled mattress cover (the Eight Sleep Pod). A total of 54 subjects wore a home sleep test device (HST) for eight nights: four nights each with Pod ON and OFF (>300 total HST nights). Nightly sleeping heart rate (HR) and heart rate variability (HRV) were collected. Compared to Pod OFF, men and women sleeping at cooler temperatures in the first half of the night significantly improved deep (+14 min; +22% mean change; p = 0.003) and REM (+9 min; +25% mean change; p = 0.033) sleep, respectively. Men sleeping at warm temperatures in the second half of the night significantly improved light sleep (+23 min; +19% mean change; p = 0.023). Overall, sleeping HR (-2% mean change) and HRV (+7% mean change) significantly improved with Pod ON (p < 0.01). To our knowledge, this is the first study to show a continuously temperature-regulated bed surface can (1) significantly modify time spent in specific sleep stages in certain parts of the night, and (2) enhance cardiovascular recovery during sleep.

Predicting the macrovascular contribution to resting-state fMRI functional connectivity at 3 Tesla: A model-informed approach

Macrovascular biases have been a long-standing challenge for fMRI, limiting its ability to detect spatially specific neural activity. Recent experimental studies, including our own (Huck et al., 2023; Zhong et al., 2023), found substantial resting-state macrovascular BOLD fMRI contributions from large veins and arteries, extending into the perivascular tissue at 3 T and 7 T. The objective of this study is to demonstrate the feasibility of predicting, using a biophysical model, the experimental resting-state BOLD fluctuation amplitude (RSFA) and associated functional connectivity (FC) values at 3 Tesla. We investigated the feasibility of both 2D and 3D infinite-cylinder models as well as macrovascular anatomical networks (mVANs) derived from angiograms. Our results demonstrate that: 1) with the availability of mVANs, it is feasible to model macrovascular BOLD FC using both the mVAN-based model and 3D infinite-cylinder models, though the former performed better; 2) biophysical modelling can accurately predict the BOLD pairwise correlation near to large veins (with R 2 ranging from 0.53 to 0.93 across different subjects), but not near to large arteries; 3) compared with FC, biophysical modelling provided less accurate predictions for RSFA; 4) modelling of perivascular BOLD connectivity was feasible at close distances from veins (with R 2 ranging from 0.08 to 0.57), but not arteries, with performance deteriorating with increasing distance. While our current study demonstrates the feasibility of simulating macrovascular BOLD in the resting state, our methodology may also apply to understanding task-based BOLD. Furthermore, these results suggest the possibility of correcting for macrovascular bias in resting-state fMRI and other types of fMRI using biophysical modelling based on vascular anatomy.

Effects of a training intervention tailored to the menstrual cycle on endurance performance and hemodynamics

BACKGROUND

This study aimed to compare the effects of block periodized training and training adapted to the menstrual cycle (MC) phases on endurance performance, cardiovascular parameters, recovery, and MC-related symptoms in active females.

METHODS

Fourteen naturally menstruating, moderately trained females (age: 24±3 years; BMI: 22.3±2.7) were randomized into an intervention (INT) and a control (CON) group. Throughout an 8-week intervention period, both groups participated in a polarized training program. In the INT, the training sessions were adapted to the MC with higher training loads within the mid and late follicular phase. Before and after the intervention maximal oxygen consumption (VO2max), velocity and heart rate at ventilatory thresholds one and two (vVT1, vVT2, hrVT1, hrVT2), systolic and diastolic blood pressure (sBP, dBP), root mean square of successive RR interval differences (RMSSD), standard deviation of NN intervals (SDNN), pulse wave velocity (PWV), and the premenstrual assessment form (PAF) were assessed.

RESULTS

There were no significant time × group interaction effects in all physiological parameters (VO2max: P=0.890; vVT1: P=1.000; hrVT1: P=0.464; vVT2: P=0.356; hrVT2: P=0.762 sBP: P=0.948; dBP: P=0.203; RMSSD: P=0.257; SDNN: P=0.241; PWV: P=0.818), or psychological parameters (PAF: P=0.745).

CONCLUSIONS

Tailoring a polarized training program to the MC did not augment training responses compared to a regular training program in active females. However, a substantial portion of the training intervention in the CON was coincidentally matched to the MC.

A 2-week high-intensity interval training intervention improves ejaculation control among men with premature ejaculation

BACKGROUND

Premature ejaculation (PE), which leads to substantial distress in men and their partners, is a common male sexual dysfunction worldwide. However, there is still a lack of effective treatments without side effects.

OBJECTIVES

We investigated the effect of high-intensity interval training (HIIT) on PE symptoms.

MATERIALS AND METHODS

We recruited 92 Chinese men aged 18-36 to complete the experiment. There were 22 (13 in the control group; 9 in the HIIT group) men diagnosed with PE and 70 (41 in the control group; 29 in the HIIT group) men with normal ejaculatory function. In the HIIT group, participants completed HIIT exercises every morning for 14 days. Participants also completed surveys inquiring about demographic information, erectile function, PE symptoms, body image (including sexual body image), physical activity, and sexual desire. The heart rate was measured before and after each HIIT. In the control group, participants were instructed not to do HIIT, but other procedures were the same as in the HIIT group.

RESULTS

Results indicated that the HIIT intervention alleviated PE symptoms in men with PE. In addition, in the HIIT group, men with PE who had a higher heart-rate increase during the HIIT intervention reported the greatest overall decrements in PE symptoms. In men with normal ejaculatory function, HIIT did not decrease PE symptoms. In addition, increments in the heart rate during the intervention were associated with more pronounced PE symptoms post-intervention in this group. Analyses of secondary outcome measures suggested that the HIIT intervention improved general and sexual body image satisfaction of men with PE compared to before the intervention.

DISCUSSION AND CONCLUSION

In summary, HIIT intervention may reduce PE symptoms in men with PE. The heart-rate increase during the intervention may be a key factor influencing the effect of the HIIT intervention on PE symptoms.

Feasibility and Preliminary Effectiveness of the INSPIRE Pilot Study for Adolescent Girls

INTRODUCTION

This pilot study evaluated the feasibility and preliminary effectiveness of the Intervention to Support Physical Activity Independence and Routine Everyday program.

METHOD

This quasi-experimental single-group pretest/posttest study included adolescent girls (n = 15) who received a Fitbit Inspire 2 wearable activity tracker and participated in the seven-week Intervention to Support Physical Activity Independence and Routine Everyday program on a college campus in the Midwest. Feasibility outcomes included intervention participation, fidelity, and satisfaction. Preliminary effectiveness outcomes included moderate-to-vigorous physical activity, cardiorespiratory fitness, and resting heart rate.

RESULTS

For intervention sessions, the mean attendance rate was 83.42%, the mean minutes of moderate-to-vigorous physical activity was 62.03, and the mean satisfaction score was 28.90. Moderate-to-vigorous physical activity and resting heart rate improved significantly from baseline to postintervention, but cardiorespiratory fitness did not.

DISCUSSION

Results suggest the need for a pilot randomized controlled trial to improve cardiorespiratory fitness and incorporating an objective measure of moderate-to-vigorous physical activity.

Elevated IL-1β and Comparable IL-1 Receptor Antagonist Levels Are Characteristic Features of L-PRP in Female College Athletes Compared to Male Professional Soccer Players

Autologous platelet-rich plasma (PRP) therapy has been becoming popular for the treatment of musculotendinous injuries among athletes. However, for individual and practical variations, clinical success is hardly predictable. To overcome this difficulty, we have been exploring possible criterion candidates for monitoring its clinical effectiveness. In this study, we focused on sex-based differences in young elite athletes and compared the biochemical compositions of their PRP. Leukocyte-rich PRP (L-PRP) was manually prepared from blood samples collected from male professional soccer players (mPSPs) (n = 25) and female college athletes (fCAs) (n = 36). Platelet-derived growth factor-BB (PDGF-BB), transforming-growth factor-β1 (TGFβ1), platelet factor-4 (PF4), interleukin-1β (IL-1β), and IL-1 receptor antagonist (IL-1RA) were quantified using an enzyme-linked immunosorbent assay. The levels of PDGF-BB, TGFβ1, and PF4 in L-PRP were significantly higher in mPSPs than in fCAs. Conversely, IL-1β and IL-1RA were detected at significantly and slightly higher levels, respectively, in fCAs than in mPSPs. Our findings suggest that, even though L-PRP from fCAs may have lower potential to induce cell growth and differentiation than that of mPSPs, due to the latter's higher capacity to control inflammation, it does not necessarily imply that PRP treatment in fCAs is less effective. Thus, these cytokine levels should be checked before PRP therapy.

Metabolic patterns of sweat-extracellular vesicles during exercise and recovery states using clinical grade patches

Background: Metabolite-based sensors are attractive and highly valued for monitoring physiological parameters during rest and/or during physical activities. Owing to their molecular composition consisting of nucleic acids, proteins, and metabolites, extracellular vesicles (EVs) have become acknowledged as a novel tool for disease diagnosis. However, the evidence for sweat related EVs delivering information of physical and recovery states remains to be addressed. Methods: Taking advantage of our recently published methodology allowing the enrichment and isolation of sweat EVs from clinical patches, we investigated the metabolic load of sweat EVs in healthy participants exposed to exercise test or recovery condition. -Ten healthy volunteers (-three females and -seven males) were recruited to participate in this study. During exercise test and recovery condition, clinical patches were attached to participants' skin, on their back. Following exercise test or recovery condition, the patches were carefully removed and proceed for sweat EVs isolation. To explore the metabolic composition of sweat EVs, a targeted global metabolomics profiling of 41 metabolites was performed. Results: Our results identified seventeen metabolites in sweat EVs. These are associated with amino acids, glutamate, glutathione, fatty acids, creatine, and glycolysis pathways. Furthermore, when comparing the metabolites' levels in sweat EVs isolated during exercise to the metabolite levels in sweat EVs collected after recovery, our findings revealed a distinct metabolic profiling of sweat EVs. Furthermore, the level of these metabolites, mainly myristate, may reflect an inverse correlation with blood glucose, heart rate, and respiratory rate levels. Conclusion: Our data demonstrated that sweat EVs can be purified using routinely used clinical patches during physical activity, setting the foundations for larger-scale clinical cohort work. Furthermore, the metabolites identified in sweat EVs also offer a realistic means to identify relevant sport performance biomarkers. This study thus provides proof-of-concept towards a novel methodology that will focus on the use of sweat EVs and their metabolic composition as a non-invasive approach for developing the next-generation of sport wearable sensors.

Online Circuit Training Increases Adherence to Physical Activity: A Randomized Controlled Trial of Men with Obesity

PURPOSE

This study aimed to examine adherence to the weekly physical activity guidelines (≥150 min of aerobic activities at moderate-to-vigorous intensity and two or more sessions of strength training (yes or no)) and health outcomes during the COVID-19 pandemic for men living with obesity, 46 wk after being offered an online muscle-strengthening circuit program for 12 wk.

METHODS

Sixty men (age ≥19 yr) living with obesity (body fat percentage ≥25%) were randomly assigned to the intervention group ( n = 30) or the control condition ( n = 30) for 12 wk. The intervention group was offered an online circuit training, three sessions per week, whereas the control group received a website helping them to reach the physical activity guidelines. Adherence to the weekly physical activity guidelines was evaluated 46 wk after enrolling in the program using a heart rate tracker (Fitbit Charge 3) and an exercise log. Health outcomes (e.g., anthropometrics, body composition) were measured at baseline and after 12, 24, and 46 wk.

RESULTS

The intervention group had higher adherence to physical activity guidelines at 46 wk (36.8%) than the control group (5.3%; P = 0.02). However, no difference in health outcomes was observed between participants in the intervention group compared with the control group after 12, 24, and 46 wk.

CONCLUSIONS

Increasing adherence to exercise in men living with obesity is challenging. The proposed program increased adherence to the physical activity guidelines after about a year for men living with obesity; however, more studies are needed to understand how to improve health outcomes when following an online delivery exercise program in this population.

Enhancing Physical and Psychosocial Health of Older Adults in Saudi Arabia through Walking: Comparison between Supervised Group-Based and Non-Supervised Individual-Based Walking

Walking is widely recognized as one of the most common and effective forms of physical activity, particularly for older adults. This study examined the comparative effects of two types of walking interventions, including supervised group-based intervention (SGBI) and non-supervised individual-based intervention (NSIBI), on frailty syndrome, cognitive functions or skills, and health-related quality of life among sedentary older Saudi individuals. A 15-week double-blinded, randomized controlled trial (RCT) including three groups (two were intervention groups while the other was the control group) was conducted among older adults who were inactive to examine the effect of different forms of walking interventions on frailty syndrome, cognitive functions, and health-related quality of life. A total of 107 participants, including 65 males and 42 females, were divided into three groups, which include SGBI, NSIBI, and the control group. Frailty syndrome was measured using the physical performance test (PPT), while cognitive function and health-related quality of life were assessed using the Mini-mental State Examination (MMSE) and the Short Form 36 (SF 36) health survey questionnaire. One-way repeated measures analysis of variance (ANOVA) and one-way analysis of covariance (ANCOVA) with the pre- and post-tests were performed for within- and between-group differences. while post-test data for the control group participants were absent due to the change in elderly center regulation, and they were excluded from the analysis. Hence, the comparison was stated only between the intervention groups. Both of the intervention groups (SGBI and NSIBI) showed significant within-subject differences in the Physical Function subscale of the health-related quality of life scale only, with F(1,20) = 23.03, p < 0.001, and F(1,18) = 27.22, p < 0.001, respectively. On the other hand, the Physical Performance Test revealed significant [F(2,51) = 9.21, p < 0.001] between-group differences in the post-test based on the baseline values. In addition, the average step count of older adults was increased from 4000 steps per session to around 7000 steps per session in the intervention group. The average heart rate of the NSIBI group did not show a visible change, and the resting heart rate of both groups showed a slightly declining trend throughout the intervention period. The walking intervention significantly increased participants' physical function, which is a component of health-related quality of life and physical performance (frailty level), along with average daily step counts for older adults in Saudi Arabia. Regular engagement in the recommended level of walking is strongly advisable for Saudi Arabian older adults to maintain their overall quality of life at this stage.

Physical Fitness Variables, General Health, Dementia and Quality of Life in Individuals with Intellectual and Developmental Disabilities: A Cross-Sectional Study

The average life expectancy of individuals with intellectual and developmental disabilities (IDDs) is increasing. However, living more years does not mean living better, leading to the need for research on comorbidities associated with the aging process. Associated with this process are the physical characteristics most prevalent in an individual with IDD: low levels of all physical capacities, the accumulation of central fat, hyperglycemia, dyslipidemia, and hypertension, variables considered to be some of the main risk factors of the onset of metabolic and cardiovascular diseases, and variables that can negatively impact quality of life (QoL). Therefore, the aim of this study is to evaluate a sample of 21 institutionalized adults with IDD (42.81 ± 10.99 years old) in terms of their anthropometric characteristics, body composition, general health status, functional capacity, neuromuscular capacity, and dementia/cognitive function, and the possible associations with QoL. All assessments were performed in the laboratory of the Faculty of Sport Sciences and Physical Education-University of Coimbra. Participants, in the present study, have low levels of physical fitness and high metabolic and cardiovascular markets, which need to be improved. On the other hand, functional and neuromuscular ability seems to be associated with QoL (p ≤ 0.05). This study highlights the role of primary and secondary care providers in diagnosis, prevention, and supporting individuals with IDDs to promote QoL.

The role of symptoms severity, heart rate, and central sensitization for predicting sleep quality in patients with fibromyalgia

BACKGROUND

Clinical predictors of sleep quality in patients with fibromyalgia syndrome (FMS) are still unknown. By identifying these factors, we could raise new mechanistic hypotheses and guide management approaches. We aimed to describe the sleep quality of FMS patients and to explore the clinical and quantitative sensory testing (QST) predictors of poor sleep quality and its subcomponents.

METHODS

This study is a cross-sectional analysis of an ongoing clinical trial. We performed linear regression models between sleep quality (Pittsburgh Sleep Quality Index [PSQI]) and demographic, clinical, and QST variables, controlling for age and gender. Predictors for the total PSQI score and its seven subcomponents were found using a sequential modeling approach.

RESULTS

We included 65 patients. The PSQI score was 12.78 ± 4.39, with 95.39% classified as poor sleepers. Sleep disturbance, use of sleep medications, and subjective sleep quality were the worst subdomains. We found poor PSQI scores were highly associated with symptom severity (FIQR score and PROMIS fatigue), pain severity, and higher depression levels, explaining up to 31% of the variance. Fatigue and depression scores also predicted the subjective sleep quality and daytime dysfunction subcomponents. Heart rate changes (surrogate of physical conditioning) predicted the sleep disturbance subcomponent. QST variables were not associated with sleep quality or its subcomponents.

CONCLUSIONS

Symptom severity, fatigue, pain, and depression (but no central sensitization) are the main predictors of poor sleep quality. Heart rate changes independently predicted the sleep disturbance subdomain (the most affected one in our sample), suggesting an essential role of physical conditioning in modulating sleep quality in FMS patients. This underscores the need for multidimensional treatments targeting depression and physical activity to improve the sleep quality of FMS patients.

Mind over body: Interfering with the inner voice is detrimental to endurance performance

In two preregistered experiments, we investigated whether covert language is involved in sustained physical efforts, specifically if people are less able to push themselves physically when distracted from using inner speech. In both experiments, participants performed 12 cycling trials (Experiment 1: N = 49; Experiment 2: N = 50), each lasting 1 min where participants were required to cycle as fast as possible while simultaneously engaging in either a visuospatial task, a verbal task or no interference. Experiment 1: Participants performed worse in the verbal interference condition compared with the control condition (d = 0.29) and verbal interference performance was numerically but not significantly worse than visuospatial interference (d = 0.22). Experiment 2: A more demanding interference task yielded significant slower cycling with verbal interference compared to both control (d = 1) and visuospatial interference (d = 0.43). These results indicate that inner speech plays a causal role in control of sustained physical efforts.

Higher Heart Rate Is Independently Associated With Abnormal Body Mass Index in a J Shape Pattern

BACKGROUND

High heart rate (HR) is independently associated with higher cardiovascular mortality and usually occurs in sedentary persons. Inactivity can also lead to obesity. The purpose of this study was to evaluate the associations between body mass index as an independent marker of high HR.

METHOD

Data generated from screening echocardiography, for the prevention of sudden death at the Anthony Bates Foundation, was used. Data from 1340 subjects, with documented HR and body mass index, between the ages 19-79 years with a mean age of 32 years, were studied. We correlated the presence of a high HR >90 beats per minute (bpm) with different body mass index (BMI) categories.

RESULTS

High HR was significantly associated with higher BMI categories and underweight subjects in adults suggesting a J shape association. A total of 22.7% of participants with an HR of more than 90 bpm had BMI >40 kg/m 2 , versus 19.0% of patients with BMI of 35-40 kg/m 2 versus 13.5% of subjects with BMI of 30-35 kg/m 2 versus 12.2% of subjects with BMI of 25-30 kg/m 2 -29.9 kg/m 2 , versus in 10.3% of subjects with BMI between 18.5 and 25 kg/m 2 , P < 0.01) Furthermore, increased HR was also more prevalent in underweight patient (17.4% in subjects with BMI < 18.5 kg/m 2 ).

CONCLUSION

High HR is strongly associated with obesity and underweight suggesting that maintaining a normal weight is associated with most positive effect on the cardiovascular system.

Effect of leisure-time physical activity on blood pressure in people with hypertension: a systematic review and meta-analysis

High blood pressure is a major risk factor for premature death. Leisure-time physical activities have been recommended to control hypertension. Studies examining how leisure-time physical activity affects blood pressure have found mixed results. We aimed to conduct a systematic review examining the effect of leisure-time physical activity (LTPA) on lowering blood pressure among adults living with hypertension. We searched studies in Embase, Medline/PubMed, Web of Science, Physical Education Index, Scopus and CENTRAL (the Cochrane Library). The primary outcome variables were systolic blood pressure (SBP) and diastolic blood pressure (DBP). This systematic review is registered on PROSPERO (CRD42021260751). We included 17 studies out of 12,046 screened articles in this review. Moderate-intensity LTPA (all types) reduced SBP compared to the non-intervention control group (MD -5.35 mm Hg, 95% CI -8.06 to -2.65, nine trials, n = 531, low certainty of the evidence). Mean DBP was reduced by -4.76 mm Hg (95% CI -8.35 to -1.17, nine trials, n = 531, low certainty of the evidence) in all types of LTPA (moderate intensity) group compared to the non-intervention control group. Leisure-time walking reduced mean SBP by -8.36 mmHg, 95% CI -13.39 to -3.32, three trials, n = 128, low certainty of the evidence). Walking during leisure time reduced -5.03 mmHg mean DBP, 95% CI -8.23 to -1.84, three trials, n = 128, low certainty of the evidence). Performing physical activity during free time probably reduces SBP and DBP (low certainty of the evidence) among adults with hypertension.

Impact of Blood-Flow-Restricted Training on Arterial Functions and Angiogenesis-A Systematic Review with Meta-Analysis

Despite growing evidence of the significant influence of blood-flow-restricted (BFR) training on different body functions, its impact on the vascular system, especially the arteries, is controversial. Therefore, the objective of our study was to analyze how BFR exercise, compared to other types of exercise without the restriction of blood flow, influences arterial functions and angiogenesis in adults. Studies comparing the effect of BFR versus non-BFR training on arterial parameters were divided into three categories: endothelial function, angiogenesis, and other vasculature functions. The search was based on Cochrane Library, PubMed^®, and Embase, and 38 studies were included. The meta-analysis revealed a more significant improvement in flow-mediated dilatation (FMD) (p = 0.002) and the production of the primary angiogenesis biomarker vascular endothelial growth factor (VEGF) (p = 0.009) after BFR compared to non-BFR training (p = 0.002). The analysis of the pulse wave velocity, ankle-brachial index, systolic blood pressure, and heart rate did not show significant differences in changes between BFR and non-BFR training. The other parameters examined did not have sufficient data to be included in the meta-analysis. The results obtained present trends that suggest significant impacts of BFR training on endothelial functions and angiogenesis. There is still a lack of multicenter randomized clinical trials including many participants, and such studies are necessary to confirm the advantage of BFR over non-BFR activity.

Effects of a 24-week exercise program on anthropometric, body composition, metabolic status, cardiovascular response, and neuromuscular capacity, in individuals with intellectual and developmental disabilities

Introduction: The prevalence of overweight and obesity has increased in the last decades, including in people with Intellectual and Developmental Disabilities (IDD). This is even more concerning when it is globally accepted that a low physical condition contributes to the deterioration of functionality and increases the risk of developing chronic diseases during life, with effective implications for health and well-being. The aim of the present study is to investigate the effects of two physical exercise intervention programs on institutionalized individuals with IDD. Methods: Twenty-one adults with IDD (43.04 ± 11.18 years) were split by convenience into three groups: i) an indoor training group (IG; N = 7; 24-week machine-based gym intervention), ii) an outdoor training group (OG; N = 7; 24-week outdoor intervention with low-content materials), and iii) a control group (CG; N = 7). Assessed outcomes included indicators of health and neuromuscular capacity. The ShapiroWilk (n < 50) and Levene tests were used to verify data normality and homoscedasticity. A Kruskal-Walli test was performed to understand if there were differences between the groups. For comparison purposes and to assess hypothetical differences between groups, the Wilcoxon signed-rank test and the Friedman test were used. The respective effect size was calculated, and the significance level was defined at 0.05. Results/Discussion: There was a difference in fat mass in OG (initial ≠ intermediate; Bonferroni corrected: t = 2.405; p = 0.048; W = 0.08 and initial ≠ final moments; Bonferroni corrected: t = 2.405; p = 0.048; W = 0.08). Indoor intervention programs seem to be more effective than outdoor intervention programs for reducing heart rate rest (t = -2.912; p = 0.011; W = -0.104) when compared with CG. Conclusion: A low-cost outdoor intervention in contact with nature appears to be more effective for fat mass reduction. The results for heart rate variability are not clear and robust. Finally, an indoor intervention using weight-training machines appears to be a good method to promote neuromuscular capacity.

Autonomic Nervous System Adaptation and Circadian Rhythm Disturbances of the Cardiovascular System in a Ground-Based Murine Model of Spaceflight

Whether in real or simulated microgravity, Humans or animals, the kinetics of cardiovascular adaptation and its regulation by the autonomic nervous system (ANS) remain controversial. In this study, we used hindlimb unloading (HU) in 10 conscious mice. Blood pressure (BP), heart rate (HR), temperature, and locomotor activity were continuously monitored with radio-telemetry, during 3 days of control, 5 days of HU, and 2 days of recovery. Six additional mice were used to assess core temperature. ANS activity was indirectly determined by analyzing both heart rate variability (HRV) and baroreflex sensitivity (BRS). Our study showed that HU induced an initial bradycardia, accompanied by an increase in vagal activity markers of HRV and BRS, together with a decrease in water intake, indicating the early adaptation to fluid redistribution. During HU, BRS was reduced; temperature and BP circadian rhythms were altered, showing a loss in day/night differences, a decrease in cycle amplitude, a drop in core body temperature, and an increase in day BP suggestive of a rise in sympathetic activity. Reloading induced resting tachycardia and a decrease in BP, vagal activity, and BRS. In addition to cardiovascular deconditioning, HU induces disruption in day/night rhythmicity of locomotor activity, temperature, and BP.

Factors associated with changes in the objectively measured physical activity among Japanese adults: A longitudinal and dynamic panel data analysis

Factors associated with dynamic changes in the objectively measured physical activity have not been well understood. We aimed to 1) evaluate the longitudinal change in the physical activity trajectory according to sex which is associated with age and to 2) determine the factors associated with the dynamic change in physical activity-related variables across a wide age range among Japanese adults. This longitudinal prospective study included 689 Japanese adults (3914 measurements) aged 26-85 years, whose physical activity data in at least two surveys were available. Physical activity-related variables, such as intensity (inactive, light [LPA; 1.5 to 2.9 metabolic equivalents (METs)], moderate-to-vigorous [MVPA; ≥3.0 METs]), total energy expenditure (TEE), physical activity level (PAL), and step count, were evaluated using a validated triaxial accelerometer. Statistical analysis involved the latent growth curve models and random-effect panel data multivariate regression analysis. During a mean follow-up period of 6.8 years, physical activity was assessed an average of 5.1 times in men and 5.9 times in women. The profiles for the inactive time, LPA (only men), MVPA, step count, PAL, and TEE showed clear curvature, indicating an accelerated rate of change around the age of 70. In contrast, other variables exhibited minimal or no curvature over the age span. The MVPA trajectory was positively associated with alcohol consumption, hand grips, leg power, and trunk flexibility and negatively associated with age, local area, body mass index (BMI), comorbidity score, and heart rate over time. Our results indicated that the physical activity trajectory revealed clear curvature, accelerated rate of change around the age of 70, and determined physical health and fitness and BMI as dynamic factors associated with physical activity changes. These findings may be useful to help support populations to achieve and maintain the recommended level of physical activity.

Wearable and mobile technology to characterize daily patterns of sleep, stress, presleep worry, and mood in adolescent insomnia

OBJECTIVES

Characterizing daily patterns of sleep, stress, presleep worry, and mood in adolescents with and without insomnia symptomatology.

DESIGN

Two months of continuous wearable tracking and daily diary ratings.

SETTING

Free-living conditions.

PARTICIPANTS

Ninety-three adolescents (59 girls; 16-19 years old) with (N = 47; 26 with clinical and 21 with sub-clinical) and without (N = 46; control) DSM-5 insomnia symptomatology.

MEASUREMENTS

Fitbit Charge 3 tracked sleep, heart rate, and steps. Evening electronic diaries collected ratings of daily stress, presleep worry, and mood.

RESULTS

While sleep duration (control: 6.88 ± 1.41 hours; insomnia: 6.92 ± 1.28 hours), architecture, timing, and night-to-night variability were similar between groups, the insomnia group reported higher levels of stress and worry, being mainly related to "school". At the intraindividual level, stress and worry predicted shorter sleep duration and earlier wake up times, which, in turn, predicted higher stress the following day. Moreover, higher-than-usual stress predicted higher sleep-time heart rate, with a more consistent effect in adolescents with insomnia. Results were overall consistent after controlling for covariates and several robustness checks.

CONCLUSIONS

There is a bidirectional relationship between daily stress and sleep, with daily stress negatively impacting sleep, which in turn leads to more stress in adolescents with and without insomnia symptoms. Findings also highlight the complexity of insomnia in adolescence, in which the core clinical features (perceived sleep difficulties) and the critical factors (stress/worry) implicated in the pathophysiology of the disorder are not necessarily reflected in objective sleep indicators.

Outdoor walking better? environmental elements of cardiorespiratory fitness training trails

In metropolitan areas where land resources are scarce, trails are a more suitable environment for cardiorespiratory fitness training for modern people. Previous studies have demonstrated that cardiorespiratory fitness is an important factor in assessing individual health and have focused on individual training performance, but the relationship between environment and cardiorespiratory fitness training participants has rarely been investigated. The purpose of this study was to investigate the demands for outdoor cardiorespiratory fitness training and a favorable trail environment by comparing the differences in exercise intensity and perceptions between outdoor and indoor environments. In this study, information on physical data, psychological feedback, and visual atmosphere was collected from nine participants during each phase of moderate intensity cardiorespiratory fitness training in indoor and outdoor environments. The results revealed that outdoor cardiorespiratory fitness training provided participants with lower training intensity during the active exercise phase and higher heart rate during the stretching phase compared to indoor training. The participants paid more attention to the slope, length, pavement, Spaciousness, and width of the trails and the circuitous route. The change of the visual atmosphere and the scenery for the environmental factors were the important factors to motivate the participants to train. The results of the study could assist participants to understand a favorable cardiorespiratory training environment and design a suitable training program, as well as provide a model for trail planning and design for government.

Strength training for arterial hypertension treatment: a systematic review and meta-analysis of randomized clinical trials

Cardiovascular diseases are the leading cause of death in the world and arterial hypertension (AH) accounts for 13.8% of deaths caused by cardiovascular diseases. Strength training interventions could be an important alternative tool for blood pressure control, however, consistent evidence and the most effective training protocol for this purpose are yet to be established. The current study used the Cochrane methodology to systematically review randomized controlled trials (RCTs) that investigated the effect of strength training on blood pressure in hypertensive patients. A systematic search was conducted in the PubMed, EMBASE, Scopus, Cochrane Library, and World Health Organization databases. This review included controlled trials that evaluated the effect of strength training for 8 weeks or more in adults with arterial hypertension, published up to December 2020. Data are described and reported as the weighted mean difference of systolic and diastolic pressure and a 95% confidence interval. Protocol registration: PROSPERO registration number CRD42020151269. A total of 14 studies were identified, including a combined total of 253 participants with hypertension. The meta-analysis showed that mean values of systolic blood pressure (SBP) and diastolic blood pressure (DBP) decreased significantly after strength training interventions. The strongest effect of strength training on decreasing blood pressure was observed in protocols with a moderate to vigorous load intensity (> 60% of one-repetition maximum-1RM), a frequency of at least 2 times per week, and a minimum duration of 8 weeks. We concluded that strength training interventions can be used as a non-drug treatment for arterial hypertension, as they promote significant decreases in blood pressure.

High-Intensity Interval Training Combined with Different Types of Exercises on Cardiac Autonomic Function. An Analytical Cross-Sectional Study in CrossFit® Athletes

It is well established that endurance exercise has positive effects on cardiac autonomic function (CAF). However, there is still a dearth of information about the effects of regular high-intensity interval training combined with different types of exercises (HIITCE) on CAF.

OBJECTIVE

The aim of this study is to compare CAF at rest, its reactivity, and reactivation following maximal exercise testing in HIITCE and endurance athletes.

METHODS

An observational study was conducted with 34 male athletes of HIITCE (i.e., CrossFit^®) [HG: n = 18; 30.6 ± 4.8 years] and endurance athletes (i.e., triathlon) [TG.: n = 16; 32.8 ± 3.6 years]. We analyzed 5 min of frequency-domain indices (TP, LF, HF, LFn, HFn, and LF/HF ratio) of heart rate variability (HRV) in both supine and orthostatic positions and its reactivity after the active orthostatic test. Post-exercise heart rate recovery (HRR) was assessed at 60, 180, and 300 s. Statistical analysis employed a non-parametric test with a p-value set at 5%.

RESULTS

The HG showed reduced HFn and increased LFn modulations at rest (supine). Overall cardiac autonomic modulation (TP) at supine and all indices of HRV at the orthostatic position were similar between groups. Following the orthostatic test, the HG showed low reactivity for all HRV indices compared to TG. After the exercise, HRR does not show a difference between groups at 60 s. However, at 180 and 300 s, an impairment of HRR was observed in HG than in TG.

CONCLUSION

At rest (supine), the HG showed reduced parasympathetic and increased sympathetic modulation, low reactivity after postural change, and impaired HRR compared to TG.

The effect of clinically elevated body mass index on physiological stress during manual lifting activities

Individuals with a body mass index (BMI) classified as obesity constitute 27.7% of U.S. workers. These individuals are more likely to experience work-related injuries. However, ergonomists still design work tasks based on the general population and normal body weight. This is particularly true for manual lifting tasks and the calculation of recommended weight limits (RWL) as per National Institute of Occupational Safety & Health (NIOSH) guidelines. This study investigates the effects of BMI on indicators of physiological stress. It was hypothesized that, for clinically elevated BMI individuals, repeated manual lifting at RWL would produce physiological stress above safety limits. A repetitive box lifting task was designed to measure metabolic parameters: volume of carbon dioxide (VCO2) and oxygen (VO2), respiratory exchange ratio (RER), heart rate (HR), and energy expenditure rate (EER). A two-way ANOVA compared metabolic variables with BMI classification and gender, and linear regressions investigated BMI correlations. Results showed that BMI classification represented a significant effect for four parameters: VCO2 (p < 0.001), VO2 (p < 0.001), HR (p = 0.012), and EER (p < 0.001). In contrast, gender only had a significant effect on VO2 (p = 0.014) and EER (p = 0.017). Furthermore, significant positive relationships were found between BMI and VCO2 (R2 = 59.65%, p < 0.001), VO2 (R2 = 45.01%, p < 0.001), HR (R2 = 21.86%, p = 0.009), and EER (R2 = 50.83%, p < 0.001). Importantly, 80% of obese subjects exceeded the EER safety limit of 4.7 kcal/min indicated by NIOSH. Indicators of physiological stress are increased in clinically elevated BMI groups and appear capable of putting these individuals at increased risk for workplace injury.

Low Heart Rate Is Associated with Cerebral Pulsatility after TIA or Minor Stroke

OBJECTIVE

Beta-blockers are beneficial in coronary artery disease but less so in stroke prevention and dementia, potentially due to reduced heart rate (HR). Cerebral pulsatility is strongly associated with cerebral small vessel disease (SVD) and may be increased by lower diastolic pressures resulting from longer cardiac cycles.

METHODS

Patients 4-6 weeks after TIA or non-disabling stroke (Oxford Vascular Study) underwent 5 minutes continuous monitoring of blood pressure (BP), electrocardiogram (ECG), and middle cerebral artery flow velocity (transcranial ultrasound). Beat-to-beat relationships between HR, blood pressure and Gosling's pulsatility index (MCA-PI) are reported as beta-coefficients from general linear models for each individual.

RESULTS

Across 759 patients, average MCA-PI during monitoring was associated with lower HR and diastolic BP (DBP) and greater systolic BP (SBP) (∆MCA-PI per 10 bpm/mmHg: -0.02, -0.04, 0.03, all p < 0.001), with HR particularly associated with low end-diastolic cerebral velocity (0.86, p = 0.014). Beat-to-beat HR was strongly associated with concurrent low DBP and high SBP, potentially mediating the association with greater beat-to-beat cerebral pulsatility (average ∆MCA-PI vs HR/DBP/SBP unadjusted: -0.062, -0.052, 0.0092; adjusted for concurrent BP: -0.039, -0.11, 0.041). The beat-to-beat association between HR and MCA-PI increased with age, beta-blockers, arterial stiffness, low HR (age > 70 + HR < 65 vs age < 70 + HR > 65: -0.081 vs -0.024, interaction p < 0.001), and severe SVD on MRI (age > 70 + severe vs age < 70 + none: -0.087 vs -0.047, interaction p = 0.03), with interactions between age, severe SVD, and low HR synergistically increasing MCA-PI.

INTERPRETATION

Low HR is associated with greater cerebral pulsatility in patients with SVD, potentially mediated by lower diastolic blood flow and representing a novel potential treatment target. ANN NEUROL 2022;92:909-920.

Monitoring one heart to help two: heart rate variability and resting heart rate using wearable technology in active women across the perinatal period

BACKGROUND

Characterizing normal heart rate variability (HRV) and resting heart rate (RHR) in healthy women over the course of a pregnancy allows for further investigation into disease states, as pregnancy is the ideal time period for these explorations due to known decreases in cardiovascular health. To our knowledge, this is the first study to continuously monitor HRV and RHR using wearable technology in healthy pregnant women.

METHODS

A total of 18 healthy women participated in a prospective cohort study of HRV and RHR while wearing a WHOOP® strap prior to conception, throughout pregnancy, and into postpartum. The study lasted from March 2019 to July 2021; data were analyzed using linear mixed models with splines for non-linear trends.

RESULTS

Eighteen women were followed for an average of 405.8 days (SD = 153). Minutes of logged daily activity decreased from 28 minutes pre-pregnancy to 14 minutes by third trimester. A steady decrease in daily HRV and increase in daily RHR were generally seen during pregnancy (HRV Est. = - 0.10, P < 0.0001; RHR Est. = 0.05, P < 0.0001). The effect was moderated by activity minutes for both HRV and RHR. However, at 49 days prior to birth there was a reversal of these indices with a steady increase in daily HRV (Est. = 0.38, P < 0.0001) and decrease in daily RHR (Est. = - 0.23, P < 0.0001), regardless of activity level, that continued into the postpartum period.

CONCLUSIONS

In healthy women, there were significant changes to HRV and RHR throughout pregnancy, including a rapid improvement in cardiovascular health prior to birth that was not otherwise known. Physical activity minutes of any type moderated the known negative consequences of pregnancy on cardiovascular health. By establishing normal changes using daily data, future research can now evaluate disease states as well as physical activity interventions during pregnancy and their impact on cardiovascular fitness.

Tele-Exercise in Non-Hospitalized versus Hospitalized Post-COVID-19 Patients

The purpose of our study was to investigate the effect of tele-exercise (TE) performed for 4 consecutive weeks on fitness indicators in hospitalized post-COVID-19 patients versus non-hospitalized patients. Forty COVID-19 survivors were included, and divided into two groups: non-hospitalized versus hospitalized. Body composition, anthropometric characteristics, pulmonary function tests, single-breath diffusing capacity for carbon monoxide, 6-min walk tests (6MWT) and handgrip strength tests were recorded before and after a TE regimen (3 sessions per week, 60 min each session, warm-up and cool-down with mobility exercises, aerobic exercise such as walking outdoors, and multi-joint strength exercises). Following TE, the 6-min walk distance and handgrip were increased in both groups, with a greater observed response in the non-hospitalized group (6MWT: 32.9 ± 46.6% vs. 18.5 ± 14.3%, p < 0.001; handgrip: 15.9 ± 12.3% vs. 8.9 ± 7.6%, p < 0.001). Self-assessed dyspnea and leg fatigue were reduced in both groups, while a higher percentage of reduction was observed in the non-hospitalized group (dyspnea: 62.9 ± 42.5% vs. 37.5 ± 49.0%, p < 0.05; leg fatigue: 50.4 ± 42.2% vs. 31.7 ± 45.1%, p < 0.05). Post- vs. pre-TE arterial blood pressure decreased significantly in both groups, with the hospitalized group exhibiting more prominent reduction (p < 0.001). Both groups benefited from the TE program, and regardless of the severity of the disease the non-hospitalized group exhibited a potentially diminished adaptative response to exercise, compared to the hospitalized group.

Effectiveness of Different Modalities of Remote Online Training in Young Healthy Males

Since 2020 there has been an increase in demand for home workouts. Therefore, different ways of delivering distance training have been proposed to promote “stay active at home.” This study aimed to compare the effectiveness of three different training programs consisting of a total of 15 workouts (three sessions per week): supervised livestreaming (LS), unsupervised following a video recording (VR), and unsupervised following a written program (WP). Changes in anthropometric and cardiovascular variables, muscle fitness, and physical activity levels were evaluated. To provide a meaningful analysis for significant comparisons between small groups, mean differences (∆), 95% confidence interval (95% C.I.), and Cohen’s effect sizes (E.S.) were also calculated. The three training modalities increased physical activity levels, with an adherence rate of LS = 93.3%, VR = 86%, and WP = 74%. Although there was no reduction in body weight, waist circumference decreased by 1.3 cm (95% C.I. = −2.1, −0.5; E.S. = 0.170; p < 0.004). Furthermore, where LS, VR, and WP resulted in improvements in muscle fitness, only LS showed changes in cardiovascular variables, such as resting heart rate (∆ = −7.3 bpm; 95% C.I. = −11.9, −2.7; E.S. = 1.296; p < 0.001) and Ruffier’s index (∆ = −2.1bpm; 95% C.I. = −3.5, −0.8; E.S. 1.099; p < 0.001). Remote online training proved its effectiveness over a short period of time. However, supervised training proved to be the most effective, highlighting the importance of an experienced trainer.

Computer vision-based approach to detect fatigue driving and face mask for edge computing device

The fatality of road accidents in this era is alarming. According to WHO, approximately 1.30 million people die each year in road accidents. Road accidents result in significant socioeconomic losses for people, their families, and the country. The integration of modern technologies into automobiles can help to reduce the number of people killed or injured in road accidents. Most of the study and police reports claim that fatigued driving is one of the deadliest factors behind many road accidents. This paper presents a complete embedded system to detect fatigue driving using deep learning, computer vision, and heart rate monitoring with Nvidia Jetson Nano developer kit, Arduino Uno, and AD8232 heart rate module. The proposed system can monitor the driver's real-time situations, then analyze the situation to detect any fatigue conditions and act accordingly. The onboard camera module constantly monitors the driver. The frames are retrieved and analyzed by the core system that uses deep learning and computer vision techniques to verify the situation with Nvidia Jetson Nano. The driver's states are identified using eye and mouth localization approaches from 68 distinct facial landmarks. Experimentally driven threshold data is employed to classify the states. The onboard heart rate module constantly measures the heart rates and detects any fluctuation in BPM related to the drowsiness. This system uses a convolutional neural network-based deep learning framework to include additional face mask detection to cope with the current pandemic situation. The heart rate module works parallelly where the other modules work in a conditional sequential manner to ensure uninterrupted detection. It will detect any sign of drowsiness in real-time and generate the alarm. The system successfully passed the initial lab tests and some actual situation experiments with 97.44% accuracy in fatigue detection and 97.90% accuracy in face mask identification. The automatic device was able to analyze different situations of drivers (different distances of driver from the camera, various lighting conditions, wearing eyeglasses, oblique projection) more precisely and generate an alarm before the accident happened.

Dysautonomia in Children with Post-Acute Sequelae of Coronavirus 2019 Disease and/or Vaccination

Long-term health problems such as fatigue, palpitations, syncope, and dizziness are well-known in patients after COVID-19 (post-acute sequelae of coronavirus (PASC)). More recently, comparable problems have been noticed after the SARS-CoV-2 vaccination (post-VAC). The pathophysiology of these problems is not well-understood. Methods: In 38 children and young adults, we tested if these health problems were related to dysautonomia in an active standing test (Group 1: 19 patients after COVID-19; Group 2: 12 patients with a breakthrough infection despite a vaccination; and Group 3: 7 patients after a vaccination without COVID-19). The data were compared with a control group of 47 healthy age-matched patients, as recently published. Results: All patients had a normal left ventricular function as measured by echocardiography. Significantly elevated diastolic blood pressure in all patient groups indicated a regulatory cardiovascular problem. Compared with the healthy control group, the patient groups showed significantly elevated heart rates whilst lying and standing, with significantly higher heart rate increases. The stress index was significantly enhanced in all patient groups whilst lying and standing. Significantly decreased pNN20 values, mostly whilst standing, indicated a lower vagus activity in all patient groups. The respiratory rates were significantly elevated in Groups 1 and 2. Conclusion: The uniform increase in the heart rates and stress indices, together with low pNN20 values, indicated dysautonomia in children with health problems after COVID-19 disease and/or vaccination. A total of 8 patients fulfilled the criteria of postural orthostatic tachycardia syndrome and 9 patients of an inappropriate sinus tachycardia, who were successfully treated with omega-3 fatty acid supplementation and pharmacotherapy.

Association of resting heart rate with cognitive decline and dementia in older adults: A population-based cohort study

INTRODUCTION

Resting heart rate (RHR) predicts future risk for cardiovascular disease (CVD). However, longitudinal studies investigating the relationship of RHR with cognitive decline are scarce.

METHODS

This population-based cohort study included 2147 participants (age≥60) in SNAC-K who were free of dementia and regularly followed from 2001-2004 to 2013-2016. RHR was assessed with electrocardiogram. Dementia was diagnosed following the Diagnostic and Statistical Manual of Mental Disorders 4th Revision criteria. Global cognitive function was assessed using Mini-Mental State Examination (MMSE). Data were analyzed using Cox and linear mixed-effects models.

RESULTS

RHR≥80 (vs. 60-69) bpm was associated with a multi-adjusted hazard ratio of 1.55 (95% confidence interval 1.06-2.27) for dementia. The association remained significant after excluding participants with prevalent and incident CVDs. Similarly, RHR≥80 bpm was associated with a multi-adjusted β-coefficient of -0.13 (-0.21 to -0.04) for MMSE score.

DISCUSSION

Higher RHR is associated with increased risk for dementia and faster cognitive decline independent of CVDs in a general population of elderly people.

Jump rope training effects on health- and sport-related physical fitness in young participants: A systematic review with meta-analysis

The aim of this systematic review with meta-analysis was to assess the available body of published peer-reviewed articles related on the effects of jump rope training (JRT) compared with active/passive controls on health- and sport-related physical fitness outcomes. Searches were conducted in three databases, including studies that satisfied the following criteria: i) healthy participants; ii) a JRT programprogramme; iii) active or traditional control group; iv) at least one measure related to health- and sport-related physical fitness; v) multi-arm trials. The random-effects model was used for the meta-analyses. Twenty-one moderate-high quality (i.e., PEDro scale) studies were meta-analysed, involving 1,021 participants (male, 50.4%). Eighteen studies included participants with a mean age <18 years old. The duration of the JRT interventions ranged from 6 to 40 weeks. Meta-analyses revealed improvements (i.e., p = 0.048 to <0.001; ES = 0.23-1.19; I² = 0.0-76.9%) in resting heart rate, body mass index, fat mass, cardiorespiratory endurance, lower- and upper-body maximal strength, jumping, range of motion, and sprinting. No significant JRT effects were noted for systolic-diastolic blood pressure, waist-hip circumference, bone or lean mass, or muscle endurance. In conclusion, JRT, when compared to active and passive controls, provides a range of small-moderate benefits that span health- and sport-related physical fitness outcomes.

Influence of Obstructive Sleep Apnea Severity on Muscle Sympathetic Nerve Activity and Blood Pressure: a Systematic Review and Meta-Analysis

BACKGROUND

We conducted meta-analyses to identify relationships between obstructive sleep apnea (OSA) severity, muscle sympathetic nerve activity (MSNA), and blood pressure (BP). We quantified the effect of OSA treatment on MSNA.

METHODS

Structured searches of electronic databases were performed until June 2021. All observational designs (except reviews) were included: population (individuals with OSA); exposures (OSA diagnosis and direct measures of MSNA); comparator (individuals without OSA or different severity of OSA); outcomes (MSNA, BP, and heart rate).

RESULTS

Fifty-six studies (N=1872) were included. MSNA burst frequency was higher in OSA (27 studies; n=542) versus controls (n=488; mean differences [MDs], +15.95 bursts/min [95% CI, 12.6-17.6 bursts/min]; I²=86%). As was burst incidence (20 studies; n=357 OSA, n=312 Controls; MD, +22.23 bursts/100 hbs [95% CI, 18.49-25.97 bursts/100 hbs]; I²=67%). Meta-regressions indicated relationships between MSNA and OSA severity (burst frequency, R²=0.489; P<0.001; burst incidence, R²=0.573; P<0.001). MSNA burst frequency was related to systolic pressure (R²=0.308; P=0.016). OSA treatment with continuous positive airway pressure reduced MSNA burst frequency (MD, 11.91 bursts/min [95% CI, 9.36-14.47 bursts/min] I²=15%) and systolic (n=49; MD, 10.3 mm Hg [95% CI, 3.5-17.2 mm Hg]; I²=42%) and diastolic (MD, 6.9 mm Hg [95% CI, 2.3-11.6 mm Hg]; I²=37%) BP.

CONCLUSIONS

MSNA is higher in individuals with OSA and related to severity. This sympathoexcitation is also related to BP in patients with OSA. Treatment effectively reduces MSNA and BP, but limited data prevents an assessment of the link between these reductions. These data are clinically important for understanding cardiovascular disease risk in patients with OSA.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: CRD42021285159.

Levels and Patterns of Physical Activity and Sedentary Behaviour of Primary School Learners in Lagos State, Nigeria

BACKGROUND

Physical activity (PA) and sedentary behaviour (SB) assessment in children is critical for the prevention of noncommunicable diseases. African studies examining PA and SB of primary school-age children are few. This study investigated PA, SB levels and their correlates among primary school children in Lagos, Nigeria.

METHOD

In a cross-sectional study of 733 learners, their self-reported PA and SB were assessed using the Children PA Questionnaire (CPAQ) (6-9 years age category) and Youth Activity Profile (YAP) (10-12 years age category) while pedometers were used for objective PA and SB assessment, and socioeconomic status (SES) index were measured using a structured questionnaire. Standardised procedures were used for anthropometric and cardiovascular measures. Results Based on CPAQ, 87.5% and 100% of the learners aged 6-9 years met the recommended PA and SB guidelines, respectively which were lower with pedometers (72.8% and 87.3%). The proportion of boys aged 6-9 years who met the guidelines for PA and SB (using pedometer) was significantly higher than that of the girls(PA: 80.7% vs. 64%, p = 0.018; SB: 94% vs. 80%, p = 0.008). Self-reported PA was positively associated with age (CPAQ: B = 455.39, p < 0.001; YAP: B = 1.638, p = 0.009) and negatively with SES (CPAQ: B = -201.39, p < 0.001; YAP: B = -1.000, p < 0.001). Objective PA was positively associated with waist to hip ratio(WHR) (6-9 years: B = 66090.24, p = 0.032) and negatively with sex (6-9 years: B = -5533.41, p = 0.027) and hip circumference (10-12 years: B = -1269.13, p = 0.017). SB was associated with SES in learners aged 10-12 years (B = -0.282, p = 0.003).

CONCLUSION

High SES is a major predictor of reduced PA among these cohort of learners.

Isotemporal Associations of Device-Measured Sedentary Time and Physical Activity with Cardiac-Autonomic Regulation in Previously Pregnant Women

BACKGROUND

High sedentary time (ST) and low physical activity may increase cardiovascular risk, potentially though cardiac-autonomic dysregulation. This study investigated associations of statistically exchanging device-measured ST and physical activity with measures of cardiac-autonomic regulation in previously pregnant women.

METHOD

This cross-sectional, secondary analysis included 286 women (age = 32.6 ± 5.7 years; 68% white) measured 7-15 years after delivery. ST and light (LPA), moderate (MPA), vigorous (VPA), and moderate-to-vigorous (MVPA) intensity physical activity were measured by ActiGraph GT3X. ST was further partitioned into long (≥ 30 min) and short (< 30 min) bouts. MVPA was also partitioned into long (≥ 10 min) and short (< 10 min) bouts. Cardiac-autonomic regulation was assessed by heart rate variability (HRV) (resting heart rate, natural log transformed standard deviation of normal R-R intervals [lnSDNN], natural log-transformed root mean square of successive differences [lnRMSSD]) from a 5-min seated ECG. Progressive isotemporal substitution models adjusted for confounders. Sensitivity analyses removed women with related underlying medical conditions and who did not meet respiration rate criteria.

RESULTS

Initial analyses found no significant associations with HRV when exchanging 30 min of ST and physical activity (p > 0.05). Yet, replacing long- and short-bout ST with 30 min of long-bout MVPA yielded significantly higher (healthier) lnRMSSD (B = 0.063 ± 0.030 and B = 0.056 ± 0.027, respectively; both p < 0.05). Sensitivity analyses strengthened these associations and yielded further associations of higher lnSDNN and lnRMSSD when replacing 30 min of short-bout MVPA with equivalent amounts of long-bout MVPA (B = 0.074 ± 0.037 and B = 0.091 ± 0.046, respectively).

CONCLUSION

Replacing ST with long-bout MVPA is a potential strategy to improve cardiac-autonomic function in previously pregnant women.

Cardiovascular disease in chronic obstructive pulmonary disease: a narrative review

Patients with chronic obstructive pulmonary disease (COPD) are at increased risk of cardiovascular disease (CVD) and concomitant disease leads to reduced quality of life, increased hospitalisations and worse survival. Acute pulmonary exacerbations are an important contributor to COPD burden and are associated with increased cardiovascular (CV) events. Both COPD and CVD represent a significant global disease impact and understanding the relationship between the two could potentially reduce this burden. The association between CVD and COPD could be a consequence of (1) shared risk factors (environmental and/or genetic) (2) shared pathophysiological pathways (3) coassociation from a high prevalence of both diseases (4) adverse effects (including pulmonary exacerbations) of COPD contributing to CVD and (5) CVD medications potentially worsening COPD and vice versa. CV risk in COPD has traditionally been associated with increasing disease severity, but there are other relevant COPD subtype associations including radiological subtypes, those with frequent pulmonary exacerbations and novel disease clusters. While the prevalence of CVD is high in COPD populations, it may be underdiagnosed, and improved risk prediction, diagnosis and treatment optimisation could lead to improved outcomes. This state-of-the-art review will explore the incidence/prevalence, COPD subtype associations, shared pathophysiology and genetics, risk prediction, and treatment of CVD in COPD.

Association between clustering of cardiovascular risk factors and resting heart rate in Chinese population: a cross-sectional study

BACKGROUND

Epidemiologic studies have explored the association between a single cardiovascular risk factor (CVRF) and resting heart rate (RHR), but the research on the relation of multiple risk factors with RHR remains scarce. This study aimed to explore the associations between CVRFs clustering and the risk of elevated RHR.

METHODS

In this cross-sectional study, adults aged 35-75 years from 31 provinces were recruited by the China PEACE Million Persons Projects from September 2015 to August 2020. We focused on seven risk factors: hypertension, diabetes mellitus, dyslipidemia, obesity, smoking, alcohol use, and low physical activity. Multivariate logistic regression was used to calculate odds ratios (OR) for elevated RHR (> 80 beats/min).

RESULTS

Among 1,045,405 participants, the mean age was 55.67 ± 9.86 years, and 60.4% of participants were women. The OR (95% CI) for elevated RHR for the groups with 1, 2, 3, 4 and ≥ 5 risk factor were 1.11 (1.08-1.13), 1.36 (1.33-1.39), 1.68 (1.64-1.72), 2.01 (1.96-2.07) and 2.58 (2.50-2.67), respectively (P _trend < 0.001). The association between the CVRFs clustering number and elevated RHR was much more pronounced in young males than in other age-sex subgroups. Clusters comprising more metabolic risk factors were associated with a higher risk of elevated RHR than those comprising more behavioral risk factors.

CONCLUSIONS

There was a significant positive association between the CVRFs clustering number and the risk of elevated RHR, particularly in young males. Compared clusters comprising more behavioral risk factors, clusters comprising more metabolic risk factors were associated with a higher risk of elevated RHR. RHR may serve as an indicator of the cumulative effect of multiple risk factors.

Comparative Efficacy of 5 Exercise Types on Cardiometabolic Health in Overweight and Obese Adults: A Systematic Review and Network Meta-Analysis of 81 Randomized Controlled Trials

BACKGROUND

Although regular exercise is recommended for preventing and treating overweight/obesity, the most effective exercise type for improving cardiometabolic health in individuals with overweight/obesity remains largely undecided. This network meta-analysis aimed to evaluate and rank the comparative efficacy of 5 exercise modalities on cardiometabolic health measures in individuals with overweight/obesity.

METHODS

A database search was conducted in MEDLINE, Embase, Scopus, and Web of Science from inception up to September 2020. The review focused on randomized controlled trials involving exercise interventions consisting of continuous endurance training, interval training, resistance training, combined aerobic and resistance training (combined training), and hybrid-type training. Exercise interventions aimed to improve somatometric variables, body composition, lipid metabolism, glucose control, blood pressure, cardiorespiratory fitness, and muscular strength. The Cochrane risk of bias tool was used to evaluate eligible studies. A random-effects network meta-analysis was performed within a frequentist framework. The intervention ranking was carried out using a Bayesian model where mean and SD were equal to the respective frequentist estimates.

RESULTS

A total of 4331 participants (59% female; mean age: 38.7±12.3 years) from 81 studies were included. Combined training was the most effective modality and hybrid-type training the second most effective in improving cardiometabolic health-related outcomes in these populations suggesting a higher efficacy for multicomponent exercise interventions compared to single-component modalities, that is, continuous endurance training, interval training, and resistance training. A subgroup analysis revealed that the effects from different exercise types were mediated by gender.

CONCLUSIONS

These findings corroborate the latest guidelines on exercise for individuals with overweight/obesity highlighting the importance of a multicomponent exercise approach to improve cardiometabolic health. Physicians and healthcare professionals should consider prescribing multicomponent exercise interventions to adults with overweight/obesity to maximize clinical outcomes.

REGISTRATION

URL: https://www.crd.york.ac.uk/PROSPERO/; Unique identifier: CRD42020202647.

Ten things to know about ten cardiovascular disease risk factors - 2022

The American Society for Preventive Cardiology (ASPC) "Ten things to know about ten cardiovascular disease risk factors - 2022" is a summary document regarding cardiovascular disease (CVD) risk factors. This 2022 update provides summary tables of ten things to know about 10 CVD risk factors and builds upon the foundation of prior annual versions of "Ten things to know about ten cardiovascular disease risk factors" published since 2020. This 2022 version provides the perspective of ASPC members and includes updated sentinel references (i.e., applicable guidelines and select reviews) for each CVD risk factor section. The ten CVD risk factors include unhealthful dietary intake, physical inactivity, dyslipidemia, pre-diabetes/diabetes, high blood pressure, obesity, considerations of select populations (older age, race/ethnicity, and sex differences), thrombosis (with smoking as a potential contributor to thrombosis), kidney dysfunction and genetics/familial hypercholesterolemia. Other CVD risk factors may be relevant, beyond the CVD risk factors discussed here. However, it is the intent of the ASPC "Ten things to know about ten cardiovascular disease risk factors - 2022" to provide a tabular overview of things to know about ten of the most common CVD risk factors applicable to preventive cardiology and provide ready access to applicable guidelines and sentinel reviews.

Effects of Sand-Based Plyometric-Jump Training in Combination with Endurance Running on Outdoor or Treadmill Surface on Physical Fitness in Young Adult Males

This study aimed at examining the effects of nine weeks of sand-based plyometric-jump training (PJT) combined with endurance running on either outdoor or treadmill surface on measures of physical fitness. Male participants (age, 20.1 ± 1.7 years) were randomly assigned to a sand-based PJT combined with endurance running on outdoor surface (OT, n = 25) or treadmill surface (TT, n = 25). The endurance running intervention comprised a mixed training method, i.e., long slow distance, tempo, and interval running drills. A control group was additionally included in this study (CG, n = 25). Participants in CG followed their regular physical activity as OT and TT but did not receive any specific intervention. Individuals were assessed for their 50-m linear sprint time, standing long jump (SLJ) distance, cardiorespiratory fitness (i.e., Cooper test), forced vital capacity (FVC), calf girth, and resting heart rate (RHR). A three (groups: OT, TT, CG) by two (time: pre, post) ANOVA for repeated measures was used to analyze the exercise-specific effects. In case of significant group-by-time interactions, Bonferroni adjusted paired (within-group) and independent (between-group comparisons at post) t-tests were used for post-hoc analyses. Significant group-by-time interactions were found for all dependent variables (p < 0.001 - 0.002, ɳ_p ² = 0.16 - 0.78). Group-specific post-hoc tests showed improvements for all variables after OT (p < 0.001, Hedges'g effect size [g] = 0.05 - 1.94) and TT (p < 0.001, g = 0.04 - 2.73), but not in the CG (p = 0.058 - 1.000, g = 0.00 - 0.34). Compared to CG, OT showed larger SLJ (p = 0.001), cardiorespiratory fitness (p = 0.004), FVC (p = 0.008), and RHR (p < 0.001) improvements. TT showed larger improvements in SLJ (p = 0.036), cardiorespiratory fitness (p < 0.001), and RHR (p < 0.001) compared with CG. Compared to OT, TT showed larger improvements for SLJ (p = 0.018). In conclusion, sand-based PJT combined with either OT or TT similarly improved most measures of physical fitness, with greater SLJ improvement after TT. Coaches may use both concurrent exercise regimes based on preferences and logistical constrains (e.g., weather; access to treadmill equipment).

Eight Weeks of Supervised Pulmonary Rehabilitation Are Effective in Improving Resting Heart Rate and Heart Rate Recovery in Severe COVID-19 Patient Survivors of Mechanical Ventilation

Background and Objectives: Patients who survive severe COVID-19 require significant pulmonary rehabilitation. Heart rate (HR) has been used as a safety variable in the evaluation of the results of interventions in patients undergoing pulmonary rehabilitation. The aim of this research was to analyse HR during a pulmonary rehabilitation program in post-severe COVID-19 patients who survived mechanical ventilation (MV). The study includes the initial and final evaluations and aerobic training sessions. Materials and Methods: Twenty patients (58 ± 13 years, 11 men) were trained for 8 weeks. A 6-minute walk test (6 MWT) was performed and, subsequently, a supervised and individualised training plan was created. Resting heart rate (RHR), heart rate recovery (HRR), heart rate at minute 6 (HR6 min) and the product of HR6 min and systolic blood pressure (HR6 minxSBP) were measured at 6 MWT. In addition, HR was measured at each training session. Results: After 8 weeks of pulmonary rehabilitation, patients decreased their RHR from 81.95 ± 9.36 to 73.60 ± 9.82 beats/min (p < 0.001) and significantly increased their HRR from 12.45 ± 10.22 to 20.55 ± 7.33 beats/min (p = 0.005). HR6 min presented a significant relationship with walking speed and walked distance after the pulmonary rehabilitation period (r = 0.555, p = 0.011 and r = 0.613, p = 0.011, respectively). HR6 minxSBP presented a significant relationship with walking speed and walked distance after training (r = 0.538, p = 0.014 and r = 0.568, p = 0.008, respectively). In the pulmonary rehabilitation sessions, a significant decrease in HR was observed at minutes 1, 6 and 15 (p < 0.05) between sessions 1 and 6 and at minute 1 between sessions 1 and 12. Conclusions: Eight weeks of individualised and supervised pulmonary rehabilitation were effective in improving RHR and HRR in COVID-19 patients surviving MV. HR is an easily accessible indicator that could help to monitor the evaluation and development of a pulmonary rehabilitation program in COVID-19 patients who survived MV.

The hormetic response of heart rate of fish embryos to contaminants - Implications for research and policy

Evidence of contaminant-induced hormesis is rapidly accumulating, while the underlying mechanisms of hormesis are becoming increasingly understood. Recent developments in this research area, and especially the emergence of the nuclear factor-erythroid factor 2-related factor 2 (Nrf2) as the master mechanism, suggest that contaminants can induce cardiac hormetic responses. This paper collates significant evidence of hormetic response of the heart rate of fish embryos to contaminants, in particular antibiotics, microplastics, and herbicides, characterized by a low-dose increase (tachycardia) and a high-dose decrease (bradycardia). The increase often occurs at doses about 100-800 times smaller than the no-observed-adverse-effect-level (NOAEL). There are also indications for even triphasic responses, which include a sub-hormetic decrease of the heart rate by doses over 10⁶ times smaller than the NOAEL. Such sub-NOAEL effects cannot be captured by linear-no-threshold (LNT) and threshold models, raising concerns about environmental health and highlighting the pressing need to consider hormetic responses in the ecological risk assessment. A visionary way forward is proposed, but addressing this research bottleneck would require improved research designs with enhanced ability and statistical power to study diphasic and triphasic responses of heart rate.

Physical Education on the Beach: An Alternative Way to Improve Primary School Children's Skill- and Health-Related Outcomes during the COVID-19 Pandemic

The COVID-19 restrictions could preclude children from participating in physical education (PE) interventions. This study aimed to evaluate the efficacy of a PE intervention conducted on the beach on children’s skill- and health-related outcomes, as a possible alternative PE intervention that could be also applied during the COVID-19 pandemic. The study involved 106 primary school children, randomly assigned to the traditional indoor (TI) intervention or to the experimental outdoor (EO) intervention. The intervention period lasted 4 months and consisted of two 1-h sessions per week. Intervention was conducted just before the beginning of the COVID-19 pandemic. Children’s anthropometric parameters (height, weight, BMI, body fat percentage, and abdominal circumference), fitness parameter (VO_2peak), health parameters (resting heart rate, and systolic and diastolic blood pressure), gross motor coordination, and physical activity level were assessed before and after intervention. Both groups significantly improved fitness and motor coordination but worsened some anthropometric parameters (weight, abdominal circumference) after the intervention period. The EO group showed a higher increase of gross motor coordination than the TI group. Results of this study demonstrated that children benefited from a well-structured PE intervention conducted in the natural environment of the beach improving physical fitness and gross motor coordination. Therefore, planning outdoor PE interventions could be an alternative and safe way to encourage and implement physical activity at school during the particular period of COVID-19 pandemic.

Dietary Intake of Adults Who Participate in CrossFit® Exercise Regimens

Background: The combination of high-intensity aerobic and high-load resistance training, as in CrossFit®, exerts similar or superior benefits to other exercise modalities. This study aimed to assess dietary habits and characterize the nutritional goals, exercise habits, and clinical health outcomes of individuals who participate in CrossFit®. Methods: Adults who are 19 y or older, with >6 mo of CrossFit® participation, completed an electronic survey and the dietary health questionnaire III. In separate models, multiple stepwise linear regressions were performed to detect the associations between (i) dietary intake, (ii) exercise habits, (iii) clinical measures, and a priori selected predictors (sex, weight status, age, and exercise frequency) in each case. Odds ratios were detected between nutritional and fitness goals, clinical outcomes, and predictors. Results: In total, 449 respondents completed both questionnaires. Of these, 443 respondents were used for relative macronutrients assessment due to not reporting body weight. Dietary intake was associated with sex, weight status, age, exercise frequency, and nutritional goals. Nutritional and fitness goals and clinical outcomes were associated with sex, weight status, age, and exercise frequency. Conclusion: Nutritional goals are underlying factors that affect eating behaviors in non-competitive CrossFit® participants. It is imperative to consider the sex, age, exercise habits, and nutritional goals of CrossFit® participants when investigating and prescribing dietary outcomes.

Benefits in cardiac function by CD38 suppression: Improvement in NAD+ levels, exercise capacity, heart rate variability and protection against catecholamine induced ventricular arrhythmias

CD38 enzymatic activity regulates NAD⁺ and cADPR levels in mammalian tissues, and therefore has a prominent role in cellular metabolism and calcium homeostasis. Consequently, it is reasonable to hypothesize about its involvement in cardiovascular physiology as well as in heart related pathological conditions.

AIM

To investigate the role of CD38 in cardiovascular performance, and its involvement in cardiac electrophysiology and calcium-handling.

METHODS AND RESULTS

When submitted to a treadmill exhaustion test, a way of evaluating cardiovascular performance, adult male CD38KO mice showed better exercise capacity. This benefit was also obtained in genetically modified mice with catalytically inactive (CI) CD38 and in WT mice treated with antibody 68 (Ab68) which blocks CD38 activity. Hearts from these 3 groups (CD38KO, CD38CI and Ab68) showed increased NAD⁺ levels. When CD38KO mice were treated with FK866 which inhibits NAD⁺ biosynthesis, exercise capacity as well as NAD⁺ in heart tissue decreased to WT levels. Electrocardiograms of conscious unrestrained CD38KO and CD38CI mice showed lower basal heart rates and higher heart rate variability than WT mice. Although inactivation of CD38 in mice resulted in increased SERCA2a expression in the heart, the frequency of spontaneous calcium release from the sarcoplasmic reticulum under stressful conditions (high extracellular calcium concentration) was lower in CD38KO ventricular myocytes. When mice were challenged with caffeine-epinephrine, CD38KO mice had a lower incidence of bidirectional ventricular tachycardia when compared to WT ones.

CONCLUSION

CD38 inhibition improves exercise performance by regulating NAD⁺ homeostasis. CD38 is involved in cardiovascular function since its genetic ablation decreases basal heart rate, increases heart rate variability and alters calcium handling in a way that protects mice from developing catecholamine induced ventricular arrhythmias.

The effect of whole-body high-intensity interval training on heart rate variability in insufficiently active adults

Background/objective

Low physical activity is a risk factor for cardiovascular disease (CVD) and all-cause morbidity and mortality. CVD alters heart rate variability (HRV). Interestingly, HRV can improve after exercise training. Therefore, this study aimed to examine the effect of whole-body high-intensity interval training (whole-body HIIT) on HRV in low physical activity adults.

Methods

Twenty-one low physical activity young adults were randomly assigned into two groups: whole-body HIIT (n = 10, females = 2/males = 8, age 22 ± 0.8 years, BMI 19.5 ± 1.0 kg/m²) and control (n = 11, females = 4/males = 7, age 21.7 ± 0.8 years, BMI 19.8 ± 0.9 kg/m²). A 6-week exercise program (3 days per week) consisting of 10 min of whole-body HIIT (burpees, mountain climbers, jumping jacks, and squats) at their maximal effort was administered. Baseline and post-training HRV (time domain: SDNN and RMSSD, frequency domain: LF, HF, and LF/HF ratio) and resting heart rate (HRrest) were recorded.

Results

The time domain parameter increased significantly in the whole-body HIIT group (SDNN; 50.95 ± 37.17 vs. 73.40 ± 40.70 ms, p < 0.05, RMSSD; 54.45 ± 56.04 vs. 81.26 ± 60.14 ms, p < 0.05). HRrest decreased significantly following training (73.94 ± 13.2 vs. 66.1 ± 10.8 bpm, p < 0.05). However, there were no significant differences in all frequency-domain parameters.

Conclusion

Six weeks of whole-body HIIT improved cardiovascular autonomic function in insufficiently active adults. Thus, whole-body HIIT might be considered an alternative exercise for reducing the risk of CVD.

Exploring Determinants of Exercise-Related Affective Valence in Regular Exercisers Between the Ages of 55 and 69 Years

This study aimed to understand determinants of recalled in-task affective valence experienced during a regularly performed aerobic bout in adult exercisers aged 55+. Qualitative data were collected (January to March, 2021, during the COVID-19 pandemic) using interviews wherein individuals (N = 16, 69% women, 61 ± 5 years) recalled deviations in affective valence in response to a regularly completed bout. Using thematic analyses, two themes emerged regarding how COVID-19 impacted regular exercise behaviors: (a) “loss” and (b) “adaptation.” Two themes encompassed the determinants of recalled in-task affective valence: (a) “person-specific conditions” and (b) “external conditions.” Finally, an increase in duration/intensity during a pleasant session was indicated by 44% of the participants, while 75% indicated a decrease in duration/intensity during an unpleasant session. The participants indicated that affective valence was determined by previously cited and novel factors that relate to exercise performed in naturalistic environments. Volitional modifications to planned exercise volume appear more responsive to feelings of displeasure.