Reliability of Zephyr Bioharness and Fitbit Charge Measures of Heart Rate and Activity at Rest, During the Modified Canadian Aerobic Fitness Test, and Recovery

Testing the hormesis hypothesis on motor behavior under stress

While much research has focused on the deleterious effects of stress on goal-directed behavior in recent decades, current views increasingly discuss growth under stress, often assuming dose-dependent effects of stress in a curvilinear association. This is based on the concept of hormesis, which postulates a strengthening effect of stress at low-to-moderate doses. Leveraging this approach, hormetic curves indicate under which stress dose an individual is able to maintain or even increase goal-directed behavior. The present study aimed to test the hormetic effect of low-to-moderate stress on tactical movement performance in the context of police operational scenarios in virtual reality. In teams of three to four, 37 riot police officers had to search a building for a potentially aggressive perpetrator in three scenarios with escalating stress potential (i.e., increasing weapon violence and number of civilians). Tactical movement performance as behavioral response was quantified by the sample entropy of each officer's velocity derived from positional data. To account for inter-individuality in response to the scenarios, we assessed self-reported stress, anxiety, mental effort, and vagally mediated heart rate variability. Specifically, we tested the quadratic associations between tactical movement performance and stress parameters, respectively. Random-intercept-random-slope regressions revealed neither significant linear nor quadratic associations between any of the stress parameters and performance. While we did not find evidence for hormesis in the present study, it stimulates theoretical discussions about the definition of "baseline" functioning and how the understanding of hormesis can move from psychological to behavioral adaptations to stressors.

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.

Study in Parkinson's disease of exercise phase 3 (SPARX3): study protocol for a randomized controlled trial

BACKGROUND

To date, no medication has slowed the progression of Parkinson's disease (PD). Preclinical, epidemiological, and experimental data on humans all support many benefits of endurance exercise among persons with PD. The key question is whether there is a definitive additional benefit of exercising at high intensity, in terms of slowing disease progression, beyond the well-documented benefit of endurance training on a treadmill for fitness, gait, and functional mobility. This study will determine the efficacy of high-intensity endurance exercise as first-line therapy for persons diagnosed with PD within 3 years, and untreated with symptomatic therapy at baseline.

METHODS

This is a multicenter, randomized, evaluator-blinded study of endurance exercise training. The exercise intervention will be delivered by treadmill at 2 doses over 18 months: moderate intensity (4 days/week for 30 min per session at 60-65% maximum heart rate) and high intensity (4 days/week for 30 min per session at 80-85% maximum heart rate). We will randomize 370 participants and follow them at multiple time points for 24 months. The primary outcome is the Movement Disorders Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) motor score (Part III) with the primary analysis assessing the change in MDS-UPDRS motor score (Part III) over 12 months, or until initiation of symptomatic antiparkinsonian treatment if before 12 months. Secondary outcomes are striatal dopamine transporter binding, 6-min walk distance, number of daily steps, cognitive function, physical fitness, quality of life, time to initiate dopaminergic medication, circulating levels of C-reactive protein (CRP), and brain-derived neurotrophic factor (BDNF). Tertiary outcomes are walking stride length and turning velocity.

DISCUSSION

SPARX3 is a Phase 3 clinical trial designed to determine the efficacy of high-intensity, endurance treadmill exercise to slow the progression of PD as measured by the MDS-UPDRS motor score. Establishing whether high-intensity endurance treadmill exercise can slow the progression of PD would mark a significant breakthrough in treating PD. It would have a meaningful impact on the quality of life of people with PD, their caregivers and public health.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04284436 . Registered on February 25, 2020.

Wearable Cardiorespiratory Sensors for Aerospace Applications

Emerging Air Traffic Management (ATM) and avionics human-machine system concepts require the real-time monitoring of the human operator to support novel task assessment and system adaptation features. To realise these advanced concepts, it is essential to resort to a suite of sensors recording neurophysiological data reliably and accurately. This article presents the experimental verification and performance characterisation of a cardiorespiratory sensor for ATM and avionics applications. In particular, the processed physiological measurements from the designated commercial device are verified against clinical-grade equipment. Compared to other studies which only addressed physical workload, this characterisation was performed also looking at cognitive workload, which poses certain additional challenges to cardiorespiratory monitors. The article also addresses the quantification of uncertainty in the cognitive state estimation process as a function of the uncertainty in the input cardiorespiratory measurements. The results of the sensor verification and of the uncertainty propagation corroborate the basic suitability of the commercial cardiorespiratory sensor for the intended aerospace application but highlight the relatively poor performance in respiratory measurements during a purely mental activity.

Estimation of Tidal Volume during Exercise Stress Test from Wearable-Device Measures of Heart Rate and Breathing Rate

Tidal volume (TV), defined as the amount of air that moves in or out of the lungs with each respiratory cycle, is important in evaluating the respiratory function. Although TV can be reliably measured in laboratory settings, this information is hardly obtainable under everyday living conditions. Under such conditions, wearable devices could provide valuable support to monitor vital signs, such as heart rate (HR) and breathing rate (BR). The aim of this study was to develop a model to estimate TV from wearable-device measures of HR and BR during exercise. HR and BR were acquired through the Zephyr Bioharness 3.0 wearable device in nine subjects performing incremental cycling tests. For each subject, TV during exercise was obtained with a metabolic cart (Cosmed). A stepwise regression algorithm was used to create the model using as possible predictors HR, BR, age, and body mass index; the model was then validated using a leave-one-subject-out cross-validation procedure. The performance of the model was evaluated using the explained variance (R2), obtaining values ranging from 0.65 to 0.72. The proposed model is a valid method for TV estimation with wearable devices and can be considered not subject-specific and not instrumentation-specific.

A Novel Intensity-Based Approach to Increasing Prefrontal Cerebral Oxygenation by Walking Exercise

Regional cerebral blood flow (rCBF) increases after moderately intense exercise and is significantly correlated with cognitive function. However, no intensity-based physiological indicator for enhancing rCBF during low- to-moderate-intensity exercise has been proposed. The purpose of this study was to develop a physiological indicator housed in a wearable device to determine whether low-to-moderate intensity walking can increase rCBF. A cross-sectional study with four parallel arms was performed. Each of 114 participants was randomly assigned to either the moderate, low-to-moderate, low, or very low walking intensity groups. A novel dynamic cardiac force meter (CFM) was used to quantify walking intensity. Heart rate and hemoencephalography (HEG) were measured during each phase of the session. Compared to baseline, HEG significantly increased in both the submaximal exercise and recovery phases in members of the low-to-moderate intensity group but not the very low intensity group. Low-to-moderate intensity walking improves prefrontal cerebral blood oxygenation. The present results demonstrate the usefulness of a dynamic CFM housed in a wearable device for quantifying the intensity of walking exercise aimed at increasing prefrontal blood oxygenation. The results of the study may help guide further development of exercise strategies for brain disease patients and the ageing population.

Remote Cardiac Rhythm Monitoring in the Era of Smart Wearables: Present Assets and Future Perspectives

Remote monitoring and control of heart function are of primary importance for patient evaluation and management, especially in the modern era of precision medicine and personalized approach. Breaking technological developments have brought to the frontline a variety of smart wearable devices, such as smartwatches, chest patches/straps, or sensors integrated into clothing and footwear, which allow continuous and real-time recording of heart rate, facilitating the detection of cardiac arrhythmias. However, there is great diversity and significant differences in the type and quality of the information they provide, thus impairing their integration into daily clinical practice and the relevant familiarization of practicing physicians. This review will summarize the different types and dominant functions of cardiac smart wearables available in the market. Furthermore, we report the devices certified by official American and/or European authorities and the respective sources of evidence. Finally, we comment pertinent limitations and caveats as well as the potential answers that flow from the latest technological achievements and future perspectives.

Initial Investigation of Athletes’ Electrocardiograms Acquired by Wearable Sensors during the Pre-exercise Phase

Aim:

The aim of this study is to support large-scale prevention programs fighting sport-related sudden cardiac death by providing a set of electrocardiographic features representing a starting point in the development of normal reference values for the pre-exercise phase.

Background:

In people with underlying, often unknown, cardiovascular abnormalities, increased cardiovascular load during exercise can trigger sport-related sudden cardiac death. Prevention remains the only weapon to contrast sport-related sudden cardiac death. So far, no reference values have been proposed for electrocardiograms of athletes acquired with wearable sensors in the pre-exercise phase, consisting of the few minutes immediately before the beginning of the training session.

Objective:

To perform an initial investigation of athletes’ electrocardiograms acquired by wearable sensors during the pre-exercise phase.

Methods:

The analyzed electrocardiograms, acquired through BioHarness 3.0 by Zephyr, belong to 51 athletes (Sport Database and Cycling Database of the Cardiovascular Bioengineering Lab of the Università Politecnica delle Marche, Italy). Preliminary values consist of interquartile ranges of six electrocardiographic features which are heart rate, heart-rate variability, QRS duration, ST level, QT interval, and corrected QT interval.

Results:

For athletes 35 years old or younger, preliminary values were [72;91]bpm, [26;47]ms, [85;104]ms, [-0.08;0.08]mm, [326;364]ms and [378;422]ms, respectively. For athletes older than 35 years old, preliminary values were [71;94]bpm, [16;65]ms, [85;100]ms, [-0.11;0.07]mm, [330;368]ms and [394;414]ms, respectively.

Conclusion:

Availability of preliminary reference values could help identify those athletes who, due to electrocardiographic features out of normal ranges, are more likely to develop cardiac complications that may lead to sport-related sudden cardiac death.

Influence of Health Related Fitness on the Morphofunctional Condition of Second Mature Aged Women

To analyze the influence of health-related fitness on the condition of second mature aged women. Participants: 65 women divided into two groups. Group 1-40 women, (43.33 ± 0.93) years old and group 2-25 women (44.40 ± 0.93) years old. The participants trained for 8 months, three times a week for 1 h. Group 1 trained dance aerobics (Monday), strength fitness (Wednesday) and stretching (Friday). Group 2 trained only stretching. The body length and mass, handgrip strength test, vital capacity, blood pressure, heart rate, Stange and Genchi tests, and motion amplitude in joints were evaluated before and after the program. The significance of the differences between the groups was evaluated by Student's criterion (t) and Rosenbaum (Q). The different intensity of the health-related effect was confirmed at the end of the program. Physiometric indicators significantly increased in group 1. The complex physical activity led to a decrease in heart rate. The results of the Stange and Genchi tests significantly increased. Goniometric indicators of group 2 increased. The comparative analysis of the participants indicators confirms the generalized and higher health-related effect of the complex fitness program. The effect of such a program showed an increase of the adaptive potential, a significant increase in the functional capabilities of women, and the optimization of the studied indicators. With the same time expenditure for health-related fitness, the complex program has a more multifaceted effect in comparison with stretching.

The Influence of Aerobic Fitness on Heart Rate Responses of Custody Assistant Recruits during Circuit Training Sessions

This study captured heart rate (HR) responses of custody assistant (CA) recruits undertaking circuit training sessions. Data from 10 male and 12 female CA recruits were analyzed. Based on YMCA step test recovery HR, recruits were divided into higher fitness (HF; top 25%), lower fitness (LF; bottom 25%), and moderate fitness (MF; remaining recruits) groups. HR was measured during two circuit training sessions featuring calisthenics and running. HR zones were defined as: very light (<57% of age-predicted maximum heart-rate [HRmax]); light (57-63% HRmax); moderate (64-76% HRmax); vigorous (77-95% HRmax); and very vigorous (>95% HRmax). A one-way ANOVA, with Bonferroni post hoc, calculated between-group differences in time spent, and percentage of total time, in the HR zones. In session one, the LF group spent less time in the light training zone compared to the MF group, and more time in the very vigorous zone compared to the HF group (p = 0.027-0.047). In session two, the LF group spent more time in the moderate zone compared to both groups, and a greater percentage of time in the very vigorous zone compared to the MF group (p = 0.002-0.004). LF recruits generally worked harder during circuit training than their fitter counterparts, which supported recommendations for ability-based modifications.

Psychometric properties of the Single Assessment Numeric Evaluation (SANE) in patients with shoulder conditions. A systematic review

BACKGROUND

Musculoskeletal injuries (i.e. shoulder pain) is the third most commonly reported symptom. The development of the Single Assessment Numeric Evaluation (SANE) scale has presented clinicians and researchers with a more efficient approach in measuring function. Therefore, it is important to establish the reliability, validity and responsiveness properties of this scale, prior to its application in research and clinic.

OBJECTIVES

To identify, critically appraise and synthesize the reported psychometric properties of the SANE scale in patients with shoulder related pathologies.

DATA SOURCES

Medline, Embase, Scopus and CINAHL databases from inception till February 2019 were searched. Two independent reviewers carried out the systematic electronic searches in each database and screened the retrieved studies and assessed their eligibility.

STUDY SELECTION OR ELIGIBILITY CRITERIA

Randomized/prospective studies, that included patients with shoulder joint related pathologies, that reported on the psychometric properties (reliability, validity, responsiveness) of SANE scale.

STUDY APPRAISAL AND SYNTHESIS METHODS

The "Quality Appraisal for Clinical Measurement Research Reports Evaluation Form" - a 12-item structured clinical measurement specific appraisal tool was used to assess studies. A qualitative synthesis was performed, and main results summarized based on the shoulder conditions, reported properties and study quality.

RESULTS

Nine studies were included. The quality ranged from 82% to 95% - very good to excellent quality. SANE scale reliability measures indicated excellent reliability properties. The Intra-class Correlation Coefficient (ICC) was ≥0.80 and Standard Error of Measurement (SEM) ranged from 4.23 to 7.82 points. Validity measures displayed correlations of 0.50-0.88 (moderate to very strong correlations) between the SANE scale and other patient reported outcomes (American Shoulder and Elbow Surgeons, Rowe score, Simple Shoulder Test, Physical Function Computerized Adaptive Test). Four studies assessed SANE scale responsiveness measures. Effect sizes of 1.5 and 0.83; and minimal clinically important differences that ranged from 27.25 to 37.05 (anchor-based approach) and 11.80 to 18.1 (distribution-based approach) were reported.

LIMITATIONS

Caution must be used when interpreting our ICCs values.

CONCLUSION IMPLICATIONS OF KEY FINDINGS

Very good to excellent quality evidence indicated that the SANE scale demonstrates evidence of a reliable, valid and responsive tool in patients with shoulder related pathologies.

SYSTEMATIC REVIEW REGISTRATION NUMBER

PROSPERO CRD42018117874.

Reliability of the Polar Vantage M Sports Watch when Measuring Heart Rate at Different Treadmill Exercise Intensities

Background: Usage of wrist-worn activity monitors has rapidly increased in recent years, and these devices are being used by both fitness enthusiasts and in clinical populations. We, therefore, assessed the test–retest reliability of the Polar Vantage M (PVM) watch when measuring heart rate (HR) during various treadmill exercise intensities. Methods: HR was measured every 30 s (simultaneous electrocardiography (ECG) and PVM). Test–retest reliability was determined using an intraclass correlation coefficient (ICC) with 95% confidence intervals (CIs). Standard error of measurement (SEM) and smallest real difference (SRD) were used to determine measurement variability. Results: A total of 29 participants completed the trials. ICC values for PVM during stages 1, 2 and 5 demonstrated good to excellent test–retest reliability (0.78, 0.78 and 0.92; 95% CI (0.54–0.90, 0.54–0.9, 0.79–0.97)). For PVM during stages 0 (rest), 3 and 4, the ICC values indicated poor to good reliability (0.42, 0.68 and 0.58; 95% CI (−0.27–0.73, 0.32–0.85, 0.14–0.80)). Conclusion: This study identified that the test–retest reliability of the PVM was comparable at low and high exercise intensities; however, it revealed a poor to good test–retest reliability at moderate intensities. The PVM should not be used in a clinical setting where monitoring of an accurate HR is crucial to the patients’ safety.

Usability of Wearable Devices With a Novel Cardiac Force Index for Estimating the Dynamic Cardiac Function: Observational Study

Background

Long-distance running can be a form of stress to the heart. Technological improvements combined with the public’s gradual turn toward mobile health (mHealth), self-health, and exercise effectiveness have resulted in the widespread use of wearable exercise products. The monitoring of dynamic cardiac function changes during running and running performance should be further studied.

Objective

We investigated the relationship between dynamic cardiac function changes and finish time for 3000-meter runs. Using a wearable device based on a novel cardiac force index (CFI), we explored potential correlations among 3000-meter runners with stronger and weaker cardiac functions during running.

Methods

This study used the American product BioHarness 3.0 (Zephyr Technology Corporation), which can measure basic physiological parameters including heart rate, respiratory rate, temperature, maximum oxygen consumption, and activity. We investigated the correlations among new physiological parameters, including CFI = weight * activity / heart rate, cardiac force ratio (CFR) = CFI of running / CFI of walking, and finish times for 3000-meter runs.

Results

The results showed that waist circumference, smoking, and CFI were the significant factors for qualifying in the 3000-meter run. The prediction model was as follows: ln (3000 meters running performance pass probability / fail results probability) = –2.702 – 0.096 × [waist circumference] – 1.827 × [smoke] + 0.020 × [ACi7]. If smoking and the ACi7 were controlled, contestants with a larger waist circumference tended to fail the qualification based on the formula above. If waist circumference and ACi7 were controlled, smokers tended to fail more often than nonsmokers. Finally, we investigated a new calculation method for monitoring cardiac status during exercise that uses the CFI of walking for the runner as a reference to obtain the ratio between the cardiac force of exercise and that of walking (CFR) to provide a standard for determining if the heart is capable of exercise. A relationship is documented between the CFR and the performance of 3000-meter runs in a healthy 22-year-old person. During the running period, data are obtained while participant slowly runs 3000 meters, and the relationship between the CFR and time is plotted. The runner’s CFR varies with changes in activity. Since the runner’s acceleration increases, the CFR quickly increases to an explosive peak, indicating the runner’s explosive power. At this period, the CFI revealed a 3-fold increase (CFR=3) in a strong heart. After a time lapse, the CFR is approximately 2.5 during an endurance period until finishing the 3000-meter run. Similar correlation is found in a runner with a weak heart, with the CFR at the beginning period being 4 and approximately 2.5 thereafter.

Conclusions

In conclusion, the study results suggested that measuring the real-time CFR changes could be used in a prediction model for 3000-meter running performance.

Psychometric Properties of Performance-Based Functional Tests in Patients With Shoulder Pathologies: A Systematic Review and Meta-analysis

OBJECTIVES

To identify, critically appraise, and synthesize the reported psychometric properties of shoulder performance-based functional tests in patients with shoulder diseases.

DATA SOURCES

MEDLINE, Embase, Scopus, and Cumulative Index to Nursing and Allied Health databases from inception until March 2019 were searched.

STUDY SELECTION

Randomized/prospective studies of patients with shoulder diseases that reported on the psychometric properties (reliability, validity, responsiveness) of performance-based functional tests (Standardized Index of Shoulder Function [FI2S], Functional Impairment Test-Hand and Neck/Shoulder/Arm, Closed Kinetic Chain Upper Extremity Stability Test, Timed Functional Arm and Shoulder Test, Shoulder Function Index [SFInX], and hand to neck, scapula, and opposite scapula).

DATA EXTRACTION

We used the Consensus-Based Standards for the Selection of Health Measurement Instruments 2018 guideline for systematic reviews. We performed a qualitative synthesis in which the results were summarized based on reported measurement properties and study quality.

DATA SYNTHESIS

Eight eligible studies were included with 28 measures (16 reliability; 10 validity; 2 responsiveness). Performance-based functional tests reliability (test-retest, intra- and interrater) measures indicated excellent reliability properties. Intraclass correlation coefficient (ICC) was ≥0.83 and standard error of the mean (SEM) ranged from 0.03-13.3 points. Validity (construct/convergent/concurrent) measures displayed correlations of -0.76 to 0.91 between performance-based functional tests and other patient-reported outcomes (Disabilities of the Arm, Shoulder, and Hand, Constant, Shoulder Pain and Disability Index). Two studies assessed the responsiveness measures performance-based functional tests. Effect sizes of 0.44 and 1.50 and minimal clinically important differences of 10.3 using the anchor-based approach were reported.

CONCLUSIONS

The FI2S and the SFInX are reliable, valid, and responsive in patients with shoulder-related diseases.

Psychometric properties of the single assessment numeric evaluation in patients with lower extremity pathologies. A systematic review

OBJECTIVES

To identify, critically appraise and synthesize the reported psychometric properties of the Single Assessment Numeric Evaluation in patients with lower extremity pathologies.

DATA SOURCES

Medline, Embase, Scopus and CINAHL databases from inception till May 2019 were searched.

STUDY SELECTION OR ELIGIBILITY CRITERIA

Studies that included patients with lower extremity pathologies that reported on the measurement properties of the Single Assessment Numeric Evaluation were included.

DATA EXTRACTION

Individual studies were appraised by two independent authors to summarize the quality of available evidence, using the COSMIN 2018 guidelines for systematic reviews of patient reported outcome measures. The results were descriptively summarized and reported.

DATA SYNTHESIS

Nine eligible studies were included. The Single Assessment Numeric Evaluation reliability measures indicated coefficients of variation <1% (doubtful quality; indeterminate properties). Validity measures displayed correlations of 0.51-0.88 between the Single Assessment Numeric Evaluation and International Knee Documentation Committee, Western Ontario/McMaster Universities Osteoarthritis Index, Knee Outcome Survey, and Revised Foot Function Index. Two measurement studies assessed the Single Assessment Numeric Evaluation responsiveness measures. Effect sizes of ≥1.75; and minimal clinically important differences of 7.0 (6 months) and 19.0 (12 months) follow ups were reported.

CONCLUSION

Adequate quality evidence with sufficient measurement properties demonstrated that the Single Assessment Numeric Evaluation is a valid tool in assessing perception of condition in female participants with knee injuries and in military population patients with ankle sprains.Implications for rehabilitationSingle Assessment Numeric Evaluation is a valid and responsive tool in assessing perception of condition in female participants with knee injuries.Single Assessment Numeric Evaluation is a valid tool in assessing perception of condition in military population patients with ankle sprains.

Sport Database: Cardiorespiratory data acquired through wearable sensors while practicing sports

Sport Database is a collection of 126 cardiorespiratory data, acquired through wearable sensors from 81 subjects while practicing 10 different sports. Each cardiorespiratory dataset consists of demographic info (gender, age, weight, height, smoking habit, alcohol consumption and weekly training rate), cardiorespiratory signals (electrocardiogram, heart-rate series, RR-interval series and breathing-rate series) and training notes. Demographic info was collected by survey. Cardiorespiratory signals were acquired through the chest strap BioHarness 3.0 by Zephyr. Eventually, training notes including the sport-dependent training protocol, were manually annotated. Sport Database may be useful to support: 1) the investigation of cardiorespiratory system adaptations to different types of physical exercise; 2) the development of automatic algorithms finalized to real-time health monitoring of athletes and preventive identification of subjects at increased risk of sport-related sudden cardiac death; and, 3) clinical testing of the BioHarness 3.0 by Zephyr. Further acquisitions could involve other sports, other cardiovascular signals and/or parameters, data from different biological systems, and other acquisition devices.

Sensor Networks for Aerospace Human-Machine Systems

Intelligent automation and trusted autonomy are being introduced in aerospace cyber-physical systems to support diverse tasks including data processing, decision-making, information sharing and mission execution. Due to the increasing level of integration/collaboration between humans and automation in these tasks, the operational performance of closed-loop human-machine systems can be enhanced when the machine monitors the operator's cognitive states and adapts to them in order to maximise the effectiveness of the Human-Machine Interfaces and Interactions (HMI²). Technological developments have led to neurophysiological observations becoming a reliable methodology to evaluate the human operator's states using a variety of wearable and remote sensors. The adoption of sensor networks can be seen as an evolution of this approach, as there are notable advantages if these sensors collect and exchange data in real-time, while their operation is controlled remotely and synchronised. This paper discusses recent advances in sensor networks for aerospace cyber-physical systems, focusing on Cognitive HMI² (CHMI²) implementations. The key neurophysiological measurements used in this context and their relationship with the operator's cognitive states are discussed. Suitable data analysis techniques based on machine learning and statistical inference are also presented, as these techniques allow processing both neurophysiological and operational data to obtain accurate cognitive state estimations. Lastly, to support the development of sensor networks for CHMI² applications, the paper addresses the performance characterisation of various state-of-the-art sensors and the propagation of measurement uncertainties through a machine learning-based inference engine. Results show that a proper sensor selection and integration can support the implementation of effective human-machine systems for various challenging aerospace applications, including Air Traffic Management (ATM), commercial airliner Single-Pilot Operations (SIPO), one-to-many Unmanned Aircraft Systems (UAS), and space operations management.

Inter-Instrument Reliability and Agreement of Fitbit Charge Measurements of Heart Rate and Activity at Rest, during the Modified Canadian Aerobic Fitness Test, and in Recovery

Purpose: We determined the inter-instrument reliability and agreement parameters of the Fitbit Charge Heart Rate (Charge HR) device during three phases: rest, modified Canadian Aerobic Fitness Test (mCAFT), and recovery. Method: We recruited 60 participants for this cross-sectional measurement study using convenience and snowball sampling approaches. The performance of the Charge HR was assessed throughout the rest, mCAFT, and recovery phases. To establish inter-instrument reliability, the Charge HR variables - heart rate, steps taken, and energy expenditures - were compared with those for two other devices: the Zephyr BioHarness (ZB) for heart rate and the Fitbit One for steps taken and energy expenditure. Measurements were recorded every 30 seconds. Results: At rest, the inter-instrument intra-class correlation coefficient (ICC) (standard error of measurement [SEM]) for the Charge HR versus the ZB was ≥ 0.97 (range, min-max, 1.02-1.32). During the mCAFT and in recovery, the ICCs (SEMs) for the Charge HR and the ZB were ≥ 0.89 (range, min-max, 1.30-3.98) and ≥ 0.68 (range, min-max, 3.58-8.35), respectively. During the mCAFT only, the number of steps taken and the energy expenditure recorded by the Charge HR and the Fitbit One displayed ICCs (SEMs) of 0.97 (83.00) and 0.77 (14.70), respectively. The average agreement differences in heart rate in this pair-wise device comparison indicated mean differences of -0.20, 4.00, and 1.00 beats per minute at rest, during the mCAFT, and in recovery, respectively. Conclusions: The Charge HR heart rate variable demonstrated excellent inter-instrument reliability compared with the ZB and provided good levels of agreement. The steps taken and energy expenditure variables displayed excellent reliability measures between Charge HR and Fitbit One. Our findings may be used to capture field-based wireless measures of heart rate in various phases and provide information about possibly using the Charge HR and ZB devices interchangeably.

Variations in Physiological and Psychological Responses of Orthopaedic Surgeons and Clinical Fellows during Hip and Knee Arthroplasties

Background:

Both physical and mental stress is present within the practice of healthcare professionals, which in turn negatively affects the quality of the services provided to the population and therefore, leading to mental exhaustion of the individuals involved.

Purpose:

To track physiological and psychological responses to common hip and knee surgeries, and during clinic days, in a group of orthopaedic surgeons and their clinical fellows (trainees), and to compare the physiological and psychological results with baseline physiological stress tests.

Methods:

Heart Rate (HR), Breathing Rate (BR), and self-reported anxiety were recorded in 3 fellowship trained orthopaedic surgeons and 5 clinical fellows using a wearable Equivital EQO2 physiological monitor and the State-Trait Anxiety Inventory (STAI). Data was recorded for days in surgery as well as clinic for 6-8 hours/day. This data was compared to baseline physiological stress tests.

Results:

Mean HR and percentage of heart rate maximum (%HR-max) were not significantly different between staff and fellows throughout the surgery days regardless of the role occupied during both primary Total Hip Arthroplasty (THA) and Total Knee Arthroplasty (TKA). For Heart rate variability (HRV), there was no difference noted between staff and fellows at any moment around and during THA, however, fellows had significantly higher variability during TKA and maintained this increased variability in the postoperative period. In THA, staff failed to show any statistical difference between the HRV in the cases they were assuming the role of primary surgeon compared to the cases they were assisting and the clinic days. On the contrary, fellows showed significantly higher HRV when they were assisting during THA compared to when they were assuming the primary surgeon role or during their clinic days.

Conclusion:

Different stress patterns were noted in clinical fellows compared to the staff, especially showing a higher overall HRV during TKA.

Psychometric properties of the Zephyr bioharness device: a systematic review

BACKGROUND

Technological development and improvements in Wearable Physiological Monitoring devices, have facilitated the wireless and continuous field-based monitoring/capturing of physiologic measures in healthy, clinical or athletic populations. These devices have many applications for prevention and rehabilitation of musculoskeletal disorders, assuming reliable and valid data is collected. The purpose of this study was to appraise the quality and synthesize findings from published studies on psychometric properties of heart rate measurements taken with the Zephyr Bioharness device.

METHODS

We searched the Embase, Medline, PsycInfo, PuMed and Google Scholar databases to identify articles. Articles were appraised for quality using a structured clinical measurement specific appraisal tool. Two raters evaluated the quality and conducted data extraction. We extracted data on the reliability (intra-class correlation coefficients and standard error of measurement) and validity measures (Pearson/Spearman's correlation coefficients) along with mean differences. Agreement parameters were summarised by the average biases and 95% limits of agreement.

RESULTS

A total of ten studies were included: quality ratings ranged from 54 to 92%. The intra-class correlation coefficients reported ranged from 0.85-0.98. The construct validity coefficients compared against gold standard calibrations or other commercially used devices, ranged from 0.74-0.99 and 0.67-0.98 respectively. Zephyr Bioharness agreement error ranged from - 4.81 (under-estimation) to 3.00 (over-estimation) beats per minute, with varying 95% limits of agreement, when compared with gold standard measures.

CONCLUSION

Good to excellent quality evidence from ten studies suggested that the Zephyr Bioharness device can provide reliable and valid measurements of heart rate across multiple contexts, and that it displayed good agreements vs. gold standard comparators - supporting criterion validity.

Comparison of Canadian firefighters and healthy controls based on submaximal fitness testing and strength considering age and gender

INTRODUCTION

Few studies have addressed whether firefighters are fitter than the general population and possess sufficient levels of aerobic capacity and muscle strength to perform on-duty tasks in a safe and efficient manner, considering age and gender. We aimed to evaluate the fitness levels of Hamilton firefighters, and to determine the effects of age and gender.

METHODS

In total, 89 participants were recruited. The modified Canadian aerobic fitness test was used to determine participants' estimated maximal oxygen consumption (V_O2max) levels. For upper and lower body strength levels, a calibrated J-Tech hand-held dynamometer and a National Institute for Occupational Safety and Health (NIOSH) lifting device was used respectively.

RESULTS

Firefighters' mean (SD) V_O2max level was 40.30 ± 6.25 ml·kg^-1·min^-1. Age proved to have a statistically significant impact on V_O2max (p < 0.001). Gender displayed statistically significant effects on strength levels. Firefighters' age was the only statistically significant independent variable, and accounted for 61.00% of the variance in firefighters' aerobic capacity levels.

CONCLUSIONS

Firefighters possessed somewhat similar aerobic capacities but much higher levels of body strength when compared with the general population. With age, firefighters' aerobic capacities decreased; however, their upper and lower body strength levels remained the same.