Effect of an aerobic exercise intervention on cardiac autonomic regulation: A worksite RCT among cleaners

Occupational physical activity, all-cause mortality and incidence of cardiovascular diseases: results from three Italian cohorts

PURPOSE

To examine the association of exposure to Occupational Physical Activity (OPA) with all-cause mortality and incidence of cardiovascular diseases (CVD).

METHODS

The study population was composed of three Italian cohorts: a national cohort of employees participating in the National Health Survey 2005, followed-up until 2014 (ILS 2005), and two urban cohorts of employees resident in Turin at 2001 and 2011 censuses (TLS 2001 and TLS 2011, respectively), both followed-up until 2018. Follow-up was conducted through individual record-linkage with death registries and hospital admissions archives. Exposure to OPA was assigned through an Italian job-exposure matrix (JEM). Relative Risks of both CVD incidence and overall mortality associated with OPA quartiles (IRR) were estimated using Poisson regression models adjusted for socio-demographics and health, and in the national cohort, also for leisure time physical activity, BMI, smoking, diabetes, and hypertension.

RESULTS

Compared to the lowest quartile, the highest OPA quartile was associated in both genders with significantly increased mortality in TLS 2001 (IRR = 1.11 among men, IRR = 1.20 among women) and in TLS 2011 (IRR = 1.27 among men and IRR = 1.73 among women), whereas in the ILS 2005 cohort no association was found. Among women, high OPA was also associated with CVD risk in TLS 2001 and 2011 (IRR = 1.39 and IRR = 1.16 for the highest quartile, respectively), while in the ILS cohort in both genders only the third quartile showed a significantly higher risk.

CONCLUSION

Our results indicate that OPA does not have a beneficial effect on CVD and mortality, but rather suggest that it may produce deleterious health effects.

Beetroot Juice Produces Changes in Heart Rate Variability and Reduces Internal Load during Resistance Training in Men: A Randomized Double-Blind Crossover

Beetroot juice (BJ) has been used as a sport supplement, improving performance in resistance training (RT). However, its effect on the modulation of the autonomic nervous system has not yet been widely studied. Therefore, the objective of this randomized double-blind crossover study was to assess the effect of acute BJ supplementation compared to placebo in blood pressure (BP), heart rate (HR), heart rate variability (HRV) and internal load during RT measure as Root Mean Square of the Successive Differences between adjacent RR intervals Slope (RMSSD and RMSSD-Slope, respectively). Eleven men performed an incremental RT test (three sets at 60%, 70% and 80% of their repetition maximum) composed by back squat and bench press with. HR, HRV and RMSSD-Slope were measured during and post exercise. As the main results, RMSSD during exercise decrease in the BJ group compared to placebo (p = 0.023; ES = 0.999), there were no differences in RMSSD post-exercise, and there were differences in RMSSD-Slope between groups in favor of the BJ group (p = 0.025; ES = 1.104) with a lower internal load. In conclusion, BJ supplementation seems to be a valuable tool for the reduction in the internal load of exercise during RT measured as RMSSD-Slope while enhancing performance.

The effect of spinal manipulative therapy and home stretching exercises on heart rate variability in patients with persistent or recurrent neck pain: a randomized controlled trial

BACKGROUND

Persistent or recurrent neck pain is, together with other chronic conditions, suggested to be associated with disturbances of the Autonomic Nervous System. Acute effects on the Autonomic Nervous System, commonly measured using Heart Rate Variability, have been observed with manual therapy. This study aimed to investigate the effect on Heart Rate Variability in (1) a combination of home stretching exercises and spinal manipulative therapy versus (2) home stretching exercises alone over 2 weeks in participants with persistent or recurrent neck pain.

METHODS

A randomized controlled clinical trial was carried out in five multidisciplinary primary care clinics in Stockholm from January 2019 to April 2020. The study sample consisted of 131 participants with a history of persistent or recurrent neck. All participants performed home stretching exercises daily for 2 weeks and were scheduled for four treatments during this period, with the intervention group receiving spinal manipulative therapy in addition to the home exercises. Heart Rate Variability at rest was measured at baseline, after 1 week, and after 2 weeks, with RMSSD (Root mean square of successive RR interval differences) as the primary outcome. Both groups were blinded to the other group intervention. Thus, they were aware of the purpose of the trial but not the details of the "other" intervention. The researchers collecting data were blinded to treatment allocation, as was the statistician performing data analyses. The clinicians provided treatment for participants in both groups and could not be blinded. A linear mixed-effects model with continuous variables and person-specific random intercept was used to investigate the group-time interaction using an intention to treat analysis.

RESULTS

Sixty-six participants were randomized to the intervention group and sixty-five to the control group. For RMSSD, a B coefficient of 0.4 (p value: 0.9) was found, indicating a non-significant difference in the regression slope for each time point with the control group as reference. No statistically significant differences were found between groups for any of the Heart Rate Variability indices.

CONCLUSION

Adding four treatments of spinal manipulation therapy to a 2-week program of daily stretching exercises gave no significant change in Heart Rate Variability.

TRIAL REGISTRATION

The trial was registered 03/07/2018 at ClinicalTrials.gov, registration number: NCT03576846. ( https://pubmed.ncbi.nlm.nih.gov/31606042/ ).

Association of Behavioral Phenotypes With Changes in Sleep During a Workplace Wellness Program

PURPOSE

Examine changes in sleep duration by 3 behavioral phenotypes during a workplace wellness program with overweight and obese adults.

DESIGN

Secondary analysis of a randomized clinical trial.

SETTING

Remotely monitored intervention conducted across the United States.

SUBJECTS

553 participants with a body mass index ≥25.

INTERVENTION

Participants were randomized to 1 of 4 study arms: control, gamification with support, gamification with collaboration, and gamification with competition to increase their physical activity. All participants were issued a wrist-worn wearable device to record their daily physical activity and sleep duration.

MEASURES

The primary outcome was change in daily sleep duration from baseline during the 24 week intervention and follow-up period by study arm within behavioral phenotype class.

ANALYSIS

Linear mixed effects regression.

RESULTS

Participants who had a phenotype of less physically active and less social at baseline, in the gamification with collaboration arm, significantly increased their sleep duration during the intervention period (30.2 minutes [95% CI 6.9, 53.5], P = 0.01), compared to the control arm. There were no changes in sleep duration among participants who were more extroverted and motivated or participants who were less motivated and at-risk.

CONCLUSIONS

Changes in sleep during a physical activity intervention varied by behavioral phenotype. Behavioral phenotypes may help to precisely identify who is likely to improve sleep duration during a physical activity intervention.

Cardiorespiratory fitness, occupational aerobic workload and age: workplace measurements among blue-collar workers

BACKGROUND

The knowledge, from laboratory studies dating back to the 1950s on the importance of the association between cardiorespiratory fitness and aerobic workload for workers health, is fundamental for promoting sustainable healthy employability among ageing blue-collar workers today. However, the association between cardiorespiratory fitness and aerobic workload has not yet been documented during daily work, and we do not know if it applies to the normal work of blue-collar workers in different age groups. We aim to investigate the association between cardiorespiratory fitness and aerobic workload among blue-collar workers using measurements of 24-h heart rate collected over consecutive working days.

METHODS

We analyzed baseline cardiorespiratory fitness, assessed using a sub-maximal cycle ergometer test, and 1-4 days of 24-h heart rate measurement from 497 blue-collar workers participating in the DPHACTO study. We investigated the association between cardiorespiratory fitness and aerobic workload defined as the average percentage of heart rate reserve (%HRR), maximum %HRR and the duration time spent at a high HRR (> 30%) during working hours. The association was assessed using multivariate linear regression models adjusted for age, sex, self-rated health, shift-work, prescription medication and occupation, as well as for different age strata.

RESULTS

Higher cardiorespiratory fitness was significantly associated with decreased mean %HRR -0.32 [95% CI -0.39 to -0.25], maximum %HRR -0.35 [95% CI -0.45 to -0.25] and time spent at  ≥ 30% HRR; -1.8% [95% CI -2.2 to -1.5%]. These associations were evident across age groups, with slightly stronger associations for workers aged 46-51 (total range 18-68).

CONCLUSIONS

Higher cardiorespiratory fitness was associated with the decreased aerobic workload during normal work across all age groups and levels of work intensity. Our findings highlight the importance of cardiorespiratory fitness when considering the workload and its relevance in the promotion of healthy sustainable employment.

Factors associated with musculoskeletal symptoms and heart rate variability among cleaners - cross-sectional study

BACKGROUND

The professionals who perform cleaning activity constitute a major economic sector in Brazil. Cleaners may develop health problems related to the musculoskeletal and cardiovascular systems. It is necessary to understand the working and health conditions of cleaners in Brazil. Thus, the aim of this study was to identify factors associated with musculoskeletal symptoms and heart rate variability (HRV) among cleaners.

METHODS

A cross-sectional study conducted at a public higher education institution with 45 outsourced cleaners following approval from the institutional ethics committee. The participants answered a questionnaire addressing sociodemographic, occupational and health data, the Nordic Musculoskeletal Questionnaire, the Physical Activity Questionnaire (work and leisure) and the short version of the Copenhagen Psychosocial Questionnaire. Clinical data (height, body mass, waist-to-hip ratio and blood pressure) and heart rate variability (HRV) were also collected. Logistic and linear regression models were created to identify factors associated with symptoms and HRV.

RESULTS

The sample consisted of women (100%) predominantly older than 50 years of age (44%), without a conjugal life (64%), with three or more children (59%), low educational level (58%) and who worked less than 12 months at the company (87%). Systemic arterial hypertension (23%) was the most reported health problem. The highest frequency of musculoskeletal symptoms was identified in the lower limbs (ankles/feet: 31% in the previous 12 months and 24% in the previous 7 days; knees: 31% in the previous 12 months and 20% in the previous 7 days). Moreover, the workers reported not practicing physical activity during leisure time (84%). Psychosocial aspects indicated health risks for the dimensions "influence at work" (74%), "burnout" (59%) and "stress" (52%). Associations were found between ankle/foot symptoms and body mass index, shoulder symptoms and predictability, and knee symptoms and self-rated health and burnout. HRV indices were associated with age.

CONCLUSIONS

This study outlined the profile of female cleaners and identified risk factors. The workers exhibited musculoskeletal symptoms, which were associated with the body mass index and some psychosocial factors. HRV indices were associated with age. Thus, health promotion and prevention measures should be taken to benefit this population of workers.

Efficacy of theory-informed workplace physical activity interventions: a systematic literature review with meta-analyses

This review aimed to assess the efficacy of workplace physical activity interventions; compare the efficacy of those that were and were not informed by behaviour change theory, and outline the effectiveness of different intervention components. A search was undertaken in Medline, Embase, PsycINFO, Ovid Emcare (previously CINAHL) and SportDiscus. Randomised, non-randomised and cluster-controlled trials with objectively measured physical activity and/or measured or predicted maximal oxygen uptake (VO_2max) as outcomes were included in the review (83 papers from 79 trials). Random-effects meta-analyses of mean differences were undertaken. Workplace physical activity programmes demonstrated positive overall intervention effects for daily step counts (814.01 steps/day; CI: 446.36, 1181.67; p < 0.01; i² = 88%) and measured VO_2max (2.53 ml kg^-1 min^-1; CI: 1.69, 3.36; p < 0.01; i² = 0%) with no sub-group differences between theory- and non-theory informed interventions. Significant sub-group differences were present for predicted VO_2max (p < 0.01), with a positive intervention effect for non-theory informed studies (2.11 ml.kg^-1 min^-1; CI: 1.20, 3.02; p < 0.01; i² = 78%) but not theory-informed studies (-0.63 ml kg^-1 min^-1; CI: -1.55, 0.30; p = 0.18; i² = 0%). Longer-term follow-ups ranged from 24 weeks to 13 years, with significant positive effects for measured VO_2max (2.84 ml kg^-1 min^-1; CI: 1.41, 4.27; p < 0.01; i² = 0%). Effective intervention components included the combination of self-monitoring with a goal, and exercise sessions onsite or nearby. The findings of this review were limited by the number and quality of theory-informed studies presenting some outcomes, and confounding issues in complex interventions. Future researchers should consider rigorous testing of outcomes of theory-informed workplace physical activity interventions and incorporate longer follow-ups.

Employee Sleep and Workplace Health Promotion: A Systematic Review

OBJECTIVE

Workplace-based employee health promotion programs often target weight loss or physical activity, yet there is growing attention to sleep as it affects employee health and performance. The goal of this review is to systematically examine workplace-based employee health interventions that measure sleep duration as an outcome.

DATA SOURCE

We conducted systematic searches in PubMed, Web of Knowledge, EMBASE, Scopus, and PsycINFO (n = 6177 records).

STUDY INCLUSION AND EXCLUSION CRITERIA

To be included in this systematic review, studies must include (1) individuals aged >18 years, (2) a worker health-related intervention, (3) an employee population, and (4) sleep duration as a primary or secondary outcome.

RESULTS

Twenty studies met criteria. Mean health promotion program duration was 2.0 months (standard deviation [SD] = 1.3), and mean follow-up was 5.6 months (SD = 6.5). The mean sample size of 395 employees (SD = 700.8) had a mean age of 41.5 years (SD = 5.2). Measures of sleep duration included self-report from a general questionnaire (n = 12, 66.6%), self-report based on Pittsburgh Sleep Quality Index (n = 4, 22.2%), and self-report and actigraphy combined (n = 5, 27.7%). Studies most commonly included sleep hygiene (35.0%), yoga (25.0%), physical activity (10.0%), and cognitive-behavioral therapy for insomnia (10.0%) interventions. Across the interventions, 9 different behavior change techniques (BCTs) were utilized; the majority of interventions used 3 or fewer BCTs, while 1 intervention utilized 4 BCTs. Study quality, on average, was 68.9% (SD = 11.1). Half of the studies found workplace-based health promotion program exposure was associated with a desired increase in mean nightly sleep duration (n = 10, 50.0%).

CONCLUSIONS

Our study findings suggest health promotion programs may be helpful for increasing employee sleep duration and subsequent daytime performance.

Musical auditory stimulus acutely influences heart rate dynamic responses to medication in subjects with well-controlled hypertension

Music can improve the efficiency of medical treatment when correctly associated with drug action, reducing risk factors involving deteriorating cardiac function. We evaluated the effect of musical auditory stimulus associated with anti-hypertensive medication on heart rate (HR) autonomic control in hypertensive subjects. We evaluated 37 well-controlled hypertensive patients designated for anti-hypertensive medication. Heart rate variability (HRV) was calculated from the HR monitor recordings of two different, randomly sorted protocols (control and music) on two separate days. Patients were examined in a resting condition 10 minutes before medication and 20 minutes, 40 minutes and 60 minutes after oral medication. Music was played throughout the 60 minutes after medication with the same intensity for all subjects in the music protocol. We noted analogous response of systolic and diastolic arterial pressure in both protocols. HR decreased 60 minutes after medication in the music protocol while it remained unchanged in the control protocol. The effects of anti-hypertensive medication on SDNN (Standard deviation of all normal RR intervals), LF (low frequency, nu), HF (high frequency, nu) and alpha-1 scale were more intense in the music protocol. In conclusion, musical auditory stimulus increased HR autonomic responses to anti-hypertensive medication in well-controlled hypertensive subjects.

On the health paradox of occupational and leisure-time physical activity using objective measurements: Effects on autonomic imbalance

OBJECTIVE

Leisure-time physical activity (LTPA) has considerable benefits for cardiovascular health and longevity, while occupational physical activity (OPA) is associated with an elevated cardiovascular risk. This "health paradox" may be explained by different effects on the autonomic nervous system from OPA and LTPA. Thus, we aimed to investigate whether objectively measured OPA and LTPA are differentially associated with autonomic regulation among workers.

METHODS

The study comprised 514 blue-collar workers from the Danish cohort DPHACTO. Physical activity (i.e. walking, climbing stairs, running and cycling) was assessed objectively using accelerometers worn on the thigh, hip and trunk over multiple working days. During this period, a heart rate monitor was used to sample heart period intervals from the ECG signal. Heart rate and heart rate variability (HRV) indices were analyzed during nocturnal sleep as markers of autonomic regulation. Multiple regression analysis was used to determine the main effects of OPA and LTPA and their interaction on heart rate and HRV, adjusting for multiple confounders.

RESULTS

Statistically significant interaction was found between OPA and LTPA on heart rate (adjusted p<0.0001) and HRV indices in time (rMSSD, adjusted p = 0.004) and frequency-domains (HF, adjusted p = 0.022; LF, adjusted p = 0.033). The beneficial effect of LTPA on nocturnal heart rate and HRV clearly diminished with higher levels of OPA, and high levels of both OPA and LTPA had a detrimental effect.

CONCLUSION

We found contrasting associations for objectively measured OPA and LTPA with heart rate and HRV during sleep. Differential effects of OPA and LTPA on autonomic regulation may contribute to the physical activity health paradox.