Search results for "Variability"
showing 10 items of 904 documents
Objectively measured physical activity in Finnish employees: a cross-sectional study.
2014
Objectives: To objectively measure the amount of intensity-specific physical activity by gender and age with respect to body mass index (BMI) during workdays and days off among Finnish employees. Design: A cross-sectional study. Setting: Primary care occupational healthcare units. Participants: A sample of 9554 Finnish employees (4221 men and 5333 women; age range 18–65 years; BMI range 18.5–40 kg/m2) who participated in health assessments related to occupational health promotion. Main outcome measurements: The amount of moderate-to-vigorous (MVPA) and vigorous (VPA) physical activity (≥3 and ≥6 metabolic equivalents, respectively) was assessed by estimating the minuteto-minute oxygen consu…
Genetic analysis of reaction time variability: room for improvement?
2013
Background. Increased reaction time variability (RTV) on cognitive tasks requiring a speeded response is characteristic of several psychiatric disorders. In attention deficit hyperactivity disorder (ADHD), the association with RT is strong phenotypically and genetically, yet high RTV is not a stable impairment but shows ADHD-sensitive improvement under certain conditions, such as those with rewards. The state regulation theory proposed that the RTV difference score, which captures change from baseline to a rewarded or fast condition, specifically measures ‘state regulation’. By contrast, the interpretation of RTV baseline (slow, unrewarded) scores is debated. We aimed to investigate directl…
Patterns of male-specific inter-population divergence in Europe, West Asia and North Africa
2000
summary We typed 1801 males from 55 locations for the Y-specific binary markers YAP, DYZ3, SRY "!)$" and the (CA)n microsatellites YCAII and DYS413. Phylogenetic relationships of chromosomes with the same binary haplotype were condensed in seven large one-step networks, which accounted for 95% of all chromosomes. Their coalescence ages were estimated based on microsatellite diversity. The three largest and oldest networks undergo sharp frequency changes in three areas. The more recent network 3‐1A clearly discriminates between Western and Eastern European populations. Pairwise Fst showed an overall increment with increasing geographic distance but with a slope greatly reduced when compared …
Heart rate rather than heart rate variability is better associated with cardiorespiratory fitness in adults
2021
This study aimed to examine the association of heart rate (HR) and heart rate variability (HRV) with cardiorespiratory fitness (CRF) in adults. This cross-sectional study included 204 participants: 132 young adults (67% women; 22.3 ± 2.3 years) and 72 middle-aged adults (53% women; 53.2 ± 5 years). HR and HRV were measured using a Polar RS800CX heart rate monitor. CRF was assessed using a metabolic cart during an incremental test. HR was negatively associated with CRF relative to body weight (BW) in young adults adjusting for sex, age, and physical activity (β ranged from -0.200 to -0.195; all
Information dynamics in cardiorespiratory analyses: application to controlled breathing
2014
Voluntary adjustment of the breathing pattern is widely used to deal with stress-related conditions. In this study, effects of slow and fast breathing with a low and high inspiratory to expiratory time on heart rate variability (HRV) are evaluated by means of information dynamics. Information transfer is quantified both as the traditional transfer entropy as well as the cross entropy, where the latter does not condition on the past of HRV, thereby taking the highly unidirectional relation between respiration and heart rate into account. The results show that the cross entropy is more suited to quantify cardiorespiratory information transfer as this measure increases during slow breathing, i…
Heart rate turbulence for guiding electric therapy in patients with cardiac failure
2009
It is well-known that a reduction of the cardiac frequency variability, measurable with the Heart Rate Variability (HRV) system, is an indirect expression of the sympathetic-autonomic tone. Another index, Heart Rate Turbulence (HRT), has been recently suggested as a possible unit of measurement for the sympathetic-autonomic tone: this system allows to estimate the baro-reflex response of the carotid arteries to an early ventricular extra-systole by analysing heart rate variations induced by a premature beat.In our research we have analyzed this phenomenon in patients affected by moderate or severe cardiac failure. In particular, we divided 110 patients into two arms: subjects with or withou…
Phenotypic variability and disparities in treatment and outcomes of childhood arthritis throughout the world: an observational cohort study
2019
Made available in DSpace on 2019-10-05T16:54:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-04-01 IRCCS Istituto Giannina Gaslini Background To our knowledge, the characteristics and burden of childhood arthritis have never been studied on a worldwide basis. We aimed to investigate, with a cross-sectional study, the prevalence of disease categories, treatment methods, and disease status in patients from across different geographical areas and from countries with diverse wealth status. Methods In this multinational, cross-sectional, observational cohort study, we asked international paediatric rheumatologists from specialised centres to enrol children with a diagnosis of juvenile …
Reliability and concurrent validity of spatiotemporal stride characteristics measured with an ankle-worn sensor among older individuals
2019
Background. Wearable inertial sensors have been shown to provide valid mean gait characteristics assessments, however, assessment of variability is less convincingly established. Research question. What level of concurrent validity, and session-to-session reliability does an ankle-worn inertial measurement unit (IMU)-based gait assessment with a novel angular velocity-based gait event detection algorithm have among older adults? Methods. Twenty seven (women N = 17) participants volunteered (age 74.4 (SD 4.3) years, body mass 74.5 (12.0) kg, height 165.9 (9.9) cm). Right leg stance, swing, and stride duration and stride length, and stride velocity were concurrently assessed with motion captu…
Heart Rate Variability Monitoring during Interferential Current Application in the Lower Back Area: A Cross-Sectional Study
2021
Vasovagal reactions may occur occasionally during electrical stimulation using interferential current (IFC). The purpose of this study was to examine variations in autonomic activity during the application of IFC in asymptomatic participants by analysis of their heart rate variability (HRV). Seventy-three male volunteers were randomly assigned to a placebo group (n = 36
Associations of physical activity, sedentary time, and cardiorespiratory fitness with heart rate variability in 6- to 9-year-old children: the PANIC …
2019
Abstract Purpose To study the associations of physical activity (PA), sedentary time (ST), and cardiorespiratory fitness (CRF) with heart rate variability (HRV) in children. Methods The participants were a population sample of 377 children aged 6–9 years (49% boys). ST, light PA (LPA), moderate PA (MPA), vigorous PA (VPA), and moderate-to-vigorous PA (MVPA), and PA energy expenditure (PAEE) were assessed using a combined heart rate and movement sensor, maximal power output per kilograms of lean body mass as a measure of CRF by maximal cycle ergometer exercise test, and HRV variables (SDNN, RMSSD, LF, and HF) using 5 min resting electrocardiography. Data were analysed by linear regression ad…