The Influence of Sitting, Standing, and Stepping Bouts on Cardiometabolic Health Markers in Older Adults.

Aside from total time spent in physical activity behaviors, how time is accumulated is important for health. This study examined associations between sitting, standing, and stepping bouts, with cardiometabolic health markers in older adults. Participants from the Mitchelstown Cohort Rescreen Study (N = 221) provided cross-sectional data on activity behaviors (assessed via an activPAL3 Micro) and cardiometabolic health. Bouts of ≥10-, ≥30-, and ≥60-min sitting, standing, and stepping were calculated. Linear regression models were fitted to examine the associations between bouts and cardiometabolic health markers. Sitting (≥10, ≥30, and ≥60 min) and standing (≥10 and ≥30 min) bouts were detrimentally associated with body composition measures, lipid markers, and fasting glucose. The effect for time spent in ≥60-min sitting and ≥30-min standing bouts was larger than shorter bouts. Fragmenting sitting with bouts of stepping may be targeted to benefit cardiometabolic health. Further insights for the role of standing need to be elicited.

Maternal obesity and degree of glucose intolerance on neonatal hypoglycaemia and birth weight: a retrospective observational cohort study in women with gestational diabetes mellitus.

Gestational diabetes mellitus (GDM) is an increasing problem worldwide. Postnatal hypoglycaemia and excess foetal growth are known important metabolic complications of neonates born to women with diabetes. This retrospective cohort study aims to determine the influence of obesity and glucose intolerance on neonatal hypoglycaemia and birth weight over the 90th percentile (LGA). Data were abstracted from 303 patient medical records from singleton pregnancies diagnosed with GDM. Data were recorded during routine hospital visits. Demographic data were acquired by facilitated questionnaires and anthropometrics measured at the first antenatal appointment. Blood biochemical indices were recorded. Plasma glucose area under the curve (PG-AUC) was calculated from OGTT results as an index of glucose intolerance. OGTT results of 303 pregnant women aged between 33.6 years (29.8-37.7) diagnosed with GDM were described. Neonates of mothers with a BMI of over 30 kg/m2 were more likely to experience neonatal hypoglycaemia (24 (9.2%) vs. 23 (8.8%), p = 0.016) with odds ratio for neonatal hypoglycaemia significantly higher at 2.105, 95% CI (1.108, 4.00), p = 0.023. ROC analysis showed poor strength of association (0.587 (95% CI, .487 to .687). Neonatal LGA was neither associated with or predicted by PG-AUC nor obesity; however, multiparous women were 2.8 (95% CI (1.14, 6.78), p = 0.024) times more likely to have a baby born LGA.Conclusion: Maternal obesity but not degree of glucose intolerance increased occurrence of neonatal hypoglycaemia. Multiparous women had greater risk of neonates born LGA.What is Known:•Excess foetal growth in utero has long-term metabolic implications which track into adulthood.•Neonatal hypoglycaemia is detrimental to newborns in the acute phase with potential long-term implications on the central nervous system.What is New:•Maternal obesity but not degree of glucose intolerance in a GDM cohort increased occurrence of neonatal hypoglycaemia.•Multiparous women diagnosed had greater risk of neonates born LGA.

Test-Retest Reliability of Student-Administered Health-Related Fitness Tests in School Settings.

PURPOSE: To examine the test-retest reliability of student-administered (SA) health-related fitness tests in school settings and to compare indices of reliability with those taken by trained research-assistants. METHODS: Participants (n = 86; age: 13.43 [0.33] y) were divided into 2 groups, SA (n = 45, girls = 26) or research-assistant administered (RA; n = 41, girls = 21). The SA group had their measures taken by 8 students (age: 15.59 [0.56] y, girls = 4), and the RA group had their measures taken by 8 research-assistants (age: 21.21 [1.38], girls = 5). Tests were administered twice by both groups, 1 week apart. Tests included body mass index, handgrip strength, standing broad jump, isometric plank hold, 90° push-up, 4 × 10-m shuttle run, back-saver sit and reach, and blood pressure. RESULTS: Intraclass correlation coefficients for SA (≥.797) and RA (≥.866) groups were high, and the observed systematic error (Bland-Altman plot) between test 1 and test 2 was close to 0 for all tests. The coefficient of variation was less than 10% for all tests in the SA group, aside from the 90° push-up (24.3%). The SA group had a marginally lower combined mean coefficient of variation across all tests (6.5%) in comparison with the RA group (6.8%). CONCLUSION: This study demonstrates that, following familiarization training, SA health-related fitness tests in school-based physical education programs can be considered reliable.

Inter and intra-reliability of ultrasonography for the measurement of abdominal subcutaneous & visceral adipose tissue thickness at 12 weeks gestation.

BACKGROUND: Excess abdominal adiposity cause metabolic disturbances, particularly in pregnancy. Methods of accurate measurement are limited in pregnancy due to risks associated with these procedures. This study outlines a non-invasive methodology for the measurement of adipose tissue in pregnancy and determines the intra- and inter-observer reliability of ultrasound (US) measurements of the two components of adipose tissue (subcutaneous (SAT) and visceral adipose tissue (VAT)) within a pregnant population. METHODS: Thirty pregnant women were recruited at the end of their first trimester, from routine antenatal clinic at the University Maternity Hospital Limerick, Ireland. Measurements of adipose tissue thickness were obtained using a GE Voluson E8 employing a 1-5 MHz curvilinear array transducer. Two observers, employing methodological rigour in US technique, measured thickness of adipose tissue three times, and segmented the US image systematically in order to define measurements of SAT and VAT using specifically pre-defined anatomical landmarks. RESULTS: Intra-observer and inter-observer precision was assessed using Coefficient of Variation (CV). Measurements of SAT and total adipose for both observers were < 5% CV and < 10% CV for VAT in measures by both observers. Inter-observer reliability was assessed by Limits of Agreement (LoA). LoA were determined to be - 0.45 to 0.46 cm for SAT and - 0.34 to 0.53 cm for VAT values. Systematic bias of SAT measurement was 0.01 cm and 0.10 cm for VAT. Inter-observer precision was also assessed by coefficient of variation (CV: SAT, 3.1%; VAT, 7.2%; Total adipose, 3.0%). CONCLUSION: Intra-observer precision was found to be acceptable for measures of SAT, VAT and total adipose according to anthropometric criterion, with higher precision reported in SAT values than in VAT. Inter-observer reliability assessed by Limits-Of-Agreement (LoA) confirm anthropometrically reliable to 0.5 cm. Systematic bias was minimal for both measures, falling within 95% confidence intervals. These results suggest that US can produce reliable, repeatable and accurate measures of SAT and VAT during pregnancy.

A systematic literature review of reviews on techniques for physical activity measurement in adults: a DEDIPAC study.

The links between increased participation in Physical Activity (PA) and improvements in health are well established. As this body of evidence has grown, so too has the search for measures of PA with high levels of methodological effectiveness (i.e. validity, reliability and responsiveness to change). The aim of this "review of reviews" was to provide a comprehensive overview of the methodological effectiveness of currently employed measures of PA, to aid researchers in their selection of an appropriate tool. A total of 63 review articles were included in this review, and the original articles cited by these reviews were included in order to extract detailed information on methodological effectiveness.Self-report measures of PA have been most frequently examined for methodological effectiveness, with highly variable findings identified across a broad range of behaviours. The evidence-base for the methodological effectiveness of objective monitors, particularly accelerometers/activity monitors, is increasing, with lower levels of variability observed for validity and reliability when compared to subjective measures. Unfortunately, responsiveness to change across all measures and behaviours remains under-researched, with limited information available.Other criteria beyond methodological effectiveness often influence tool selection, including cost and feasibility. However, researchers must be aware of the methodological effectiveness of any measure selected for use when examining PA. Although no "perfect" tool for the examination of PA in adults exists, it is suggested that researchers aim to incorporate appropriate objective measures, specific to the behaviours of interests, when examining PA in free-living environments.

The impact of exercise on sleep (time, quality, and disturbance) in patients with rheumatoid arthritis: a study protocol for a pilot randomised controlled trial.

Poor sleep is an issue for people with rheumatoid arthritis (RA), which may curtail their ability to function appropriately and reduce their activity levels. This paper describes a protocol for a pilot randomised controlled trial of an aerobic exercise intervention compared with exercise advice designed to improve sleep in people with RA. Objectives are to obtain reliable estimates regarding recruitment rates, participant retention and protocol adherence and to generate potential effect size estimates for a main trial. Participants will be identified from an existing database held at a University Hospital and in person at weekly rheumatology clinics. Participants meeting the inclusion criteria will be randomised into an intervention or control group. Those in the intervention group will participate in an 8-week walking-based exercise intervention consisting of 28 walking sessions, with 1 session per week being supervised by a trained physiotherapist, spread over a maximum of 8 weeks (2-5 times/week), while those in the control group will receive advice on the benefits of exercise for people with RA. Results will provide data for efficient recruitment and data collection, to determine if a larger, statistically powered main trial could be generalised to a multi-centre rheumatoid arthritis population. Given recent information that sleep is commonly reduced in people with RA and that physical activity and exercise profiles are lower, this study will contribute data to the field of exercise and sleep that is currently lacking and importantly will include people with RA in the study process prior to any fully powered trial.Trial registration number: ClinicalTrials.gov Identifier: NCT03140995 (April 25th, 2017).

Minimum Wear Duration for the activPAL Professional Activity Monitor in Adolescent Females.

OBJECTIVES: This study aims to determine the minimum number of days of monitoring required to reliably predict sitting/lying time, standing time, light intensity physical activity (LIPA), moderate-to-vigorous intensity physical activity (MVPA) and steps in adolescent females. METHOD: 195 adolescent females (mean age = 15.7 years; SD = 0.9) participated in the study. Participants wore the activPAL activity monitor for a seven day protocol. The amount of time spent sitting/lying, standing, in LIPA and in MVPA and the number of steps per day were quantified. Spearman-Brown Prophecy formulae were used to predict the number of days of data required to achieve an intraclass correlation coefficient of both 0.7 and 0.8. RESULTS: For the percentage of the waking day spent sitting/lying, standing, in LIPA and in MVPA, a minimum of 9 days of accelerometer recording is required to achieve a reliability of ≥ 0.7, while a minimum of 15 days is required to achieve a reliability of ≥ 0.8. For steps, a minimum of 12 days of recording is required to achieve a reliability of ≥ 0.7, with 21 days to achieve a reliability of ≥ 0.8. CONCLUSION: Future research in adolescent females should collect a minimum of 9 days of accelerometer data to reliably estimate sitting/lying time, standing time, LIPA and MVPA, while 12 days is required to reliably estimate steps.

The Development of Activity Profiles in Adolescent Females and their Association with Adiposity.

OBJECTIVES: This study aims to (1) use the objective activPAL activity monitor to assess physical activity behaviors, including sitting/lying, standing, and both light (LIPA) and moderate-to-vigorous physical activity (MVPA); (2) to develop distinct activity profiles based on time spent in each behavior in a sample of adolescent females; and (3) examine whether levels of adiposity differ across these activity profiles. METHODS: Female adolescents (n = 195; 14-18 y) had body mass index (median = 21.7 [IQR = 5.2] kg/m2) and 4-site skinfold thickness (median 62.0 mm; IQR = 37.1) measured. Physical activity behaviors were measured using the activPAL. Hierarchical cluster analysis grouped participants into activity profiles based on similar physical activity characteristics. Linear mixed models explored differences in body composition across activity profiles. RESULTS: Three activity profiles were identified, a low (n = 35), moderate (n = 110), and a high activity profile (n = 50). Significant differences across activity profiles were observed for skinfold thickness (p = .046), with higher values observed in the low activity profile compared with the high activity profile. CONCLUSIONS: Profiling free-living activity using behaviors from across the activity intensity continuum may account for more of the variability in energy expenditure then examining specific activity intensities, such as MVPA alone. The use of activity profiles may enable the identification of individuals with unhealthy activity behaviors, leading to the development and implementation of more targeted interventions.

Participatory Approaches in the Context of Research Into Workplace Health Promotion to Improve Physical Activity Levels and Reduce Sedentary Behavior Among Office-Based Workers: Scoping Review.

BACKGROUND: Participatory research (PR) involves engaging in cocreation with end users and relevant stakeholders throughout the research process, aiming to distribute power equitably between the end users and research team. Engagement and adherence in previous workplace health promotion (WHP) studies have been shown to be lacking. By implementing a PR approach, the insights of end users and stakeholders are sought in the co-design of feasible and acceptable intervention strategies, thereby increasing the relevance of the research. OBJECTIVE: This scoping review aims to explore, identify, and map PR techniques and their impact when used in office-based WHP interventions designed to improve physical activity (PA) or reduce sedentary behavior (SB). METHODS: The reporting of this scoping review followed the PRISMA-ScR (Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews). A systematic literature search of 5 electronic databases-Web of Science, PubMed, Scopus, Google Scholar, and OpenGrey-was conducted, searching from January 1, 1995, to February 8, 2023. In total, 2 independent reviewers first screened the retrieved articles by title and abstract, and then assessed the full texts based on the inclusion and exclusion criteria. The search strategy and eligibility criteria were developed and guided by an a priori population (office-based working adults), intervention (a PA WHP intervention that took a PR approach), comparison (no comparison required), and outcome (PA or SB) framework. Data were charted and discussed via a narrative synthesis, and a thematic analysis was conducted. The included studies were evaluated regarding the degree of end user engagement throughout the research process and power shared by the researchers, using Arnstein's ladder of citizen participation. RESULTS: The search retrieved 376 records, of which 8 (2.1%) met the inclusion criteria. Four key strategies were identified: (1) end user focus groups, (2) management involvement, (3) researcher facilitators, and (4) workplace champions. The degree of engagement and power shared was relatively low, with 25% (2/8) of the studies determined to be nonparticipation studies, 25% (2/8) determined to be tokenistic, and 50% (4/8) determined to provide citizen power. CONCLUSIONS: This review provides a foundation of evidence on the current practices when taking a PR approach, highlighting that previous office-based PA WHP studies have been largely tokenistic or nonparticipative, and identified that the end user is only engaged with in the conception and implementation of the WHP studies. However, a positive improvement in PA and reduction in SB were observed in the included studies, which were largely attributed to implementing a PR approach and including the end user in the design of the WHP intervention. Future studies should aim to collaborate with workplaces, building capacity and empowering the workforce by providing citizen control and letting the end users "own" the research for a sustainable WHP intervention. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.1136/bmjopen-2021-054402.

Move for Life an intervention for inactive adults aged 50 years and older: a cluster randomised feasibility trial.

Background: Move for Life (MFL) is a theory-informed intervention that was developed to augment established physical activity (PA) programmes and enable inactive adults aged 50 years and older to be more active. This study examined the feasibility of MFL and sought to provide evidence of its potential for improving PA and associated health outcomes. Methods: A 3-arm cluster randomised feasibility trial compared MFL intervention, usual provision (UP) and control (CON) groups at baseline (T0), post-intervention (T1, at 8, 10 or 12- weeks) and 6-month follow up (T2). We used purposive sampling strategies to recruit participants according to characteristics of interest. Feasibility outcomes assessed recruitment, fidelity, adherence, retention and data completion rates based on pre-set criteria. Primary outcomes were accelerometer-based moderate-to-vigorous intensity PA (MVPA) and self-reported compliance with physical activity guidelines (PAGL). Secondary outcomes included light intensity PA (LiPA), standing time, sedentary time, body composition (adiposity), physical function and psychological well-being. We used linear mixed models (continuous outcomes) or generalized estimated equations (categorical outcomes) to estimate group differences over time in the study outcomes. Results: Progression criteria for feasibility outcomes were met, and 733 individuals were recruited. Considering a 6-month period (T0-T2), while self-reported compliance with PAGL increased in MFL relative to UP and CON and in UP relative to CON, standing time decreased in MFL relative to CON and sedentary time increased in the latter compared to UP. Waist circumference decreased in MFL relative to UP and CON. MFL outperformed UP in the Timed Up and Go Test while MFL and UP increased the distance covered in the Six-Minute Walk Test compared to CON. Psychological well-being increased in MFL relative to CON (all p < 0.05). Conclusion: Findings show that MFL is feasible, while data are promising with regards to the potential of improving community PA programmes for adults aged 50 or more years. Clinical trial registration: https://www.isrctn.com/Registration#ISRCTN11235176.

The Effect of an Electronic Passive Prompt Intervention on Prolonged Occupational Sitting and Light-Intensity Physical Activity in Desk-Based Adults Working from Home during COVID-19 in Ireland.

This study aimed to assess the effect of passive prompts on occupational physical behaviours (PBs) and bouts of prolonged sitting among desk-based workers in Ireland who were working from home during the COVID-19 pandemic. Electronic passive prompts were delivered every 45 min, asking participants to walk for five minutes, during working hours. Twenty-eight participants (aged 30-67 years) completed the six-week intervention between October 2020 and April 2021. PBs were measured using an activPAL3TM accelerometer, following a 24 h wear protocol, worn for the duration of the study. Participants were highly sedentary at both baseline (77.71% of work hours) and during the intervention (75.81% of work hours). However, the number of prolonged occupational sedentary bouts > 90 min was reduced compared to baseline (0.56 ± 0.08 vs. 0.77 ± 0.11, p = 0.009). Similar reductions were observed in the time spent in sustained sitting > 60 and >90 min when compared to baseline sedentary patterns (60 min: -31.27 ± 11.91 min, p = 0.014; 90 min: -27.97 ± 9.39 min, p = 0.006). Light-intensity physical activity (LIPA) significantly increased during the intervention (+14.29%, p = 0.001). This study demonstrates that passive prompts, delivered remotely, can both reduce the number and overall time spent in prolonged bouts of occupational sedentary behaviour and increase occupational LIPA.

A steps/minute value for moderate intensity physical activity in adolescent females.

The number of steps/minute (i.e., cadence) that equates to moderate intensity in adolescents is not known. To that end, 31 adolescent females walked on a treadmill at 5 different speeds while wearing an ActivPAL accelerometer and oxygen uptake was recorded by indirect calorimetry. The relationship between metabolic equivalents (METs) and cadence was explored using 3 different analytical approaches. Cadence was a significant predictor of METs (r = .70; p < .001). Moderate intensity (3 METs) corresponded to 94 or 114 steps/minute based on the mixed model and ROC analysis, respectively. These two values, and a practical value of 100 steps/minute, were cross-validated on an independent sample of 33 adolescent females during over-ground walking at 3 speeds. The sensitivity and specificity of each value correctly identifying 3 METs were 98.5% and 87.2% for 94 steps/minute, 72.9% and 98.8 for 114 steps/minute and 96.5% and 95.7% for 100 steps/minute. Compromising on a single cadence of 100 steps/minute would be a practical value that approximates moderate intensity in adolescent females and can be used for physical activity interpretation and promotion.

The Acute Effects of Interrupting Prolonged Sitting Time in Adults with Standing and Light-Intensity Walking on Biomarkers of Cardiometabolic Health in Adults: A Systematic Review and Meta-analysis.

BACKGROUND: Increasing evidence highlights that accumulating sitting time in prolonged bouts is detrimental to cardiometabolic health. OBJECTIVES: This systematic review aimed to compare the effects of fractionating prolonged sitting with frequent short bouts of standing and light-intensity walking on cardiometabolic health markers and conduct a meta-analysis for differences in systolic blood pressure (SBP), postprandial glucose and insulin. METHODS: Experimental randomised crossover trials with at least three intervention arms that assessed interrupting sitting with frequent short bouts of standing and light-intensity walking over a single day compared to a prolonged sitting condition were retrieved. These studies measured at minimum one marker of cardiometabolic health in adults > 18 years. An electronic search was completed on the 2nd of August 2021, searching PubMed and Web of Science Core Collection, Scopus, Embase, Cochrane Library and APA PsycINFO. Risk of bias was assessed using a modified Downs and Black checklist. A meta-analysis was conducted using calculated Cohen's d quantifying the magnitude of difference between experimental conditions. RESULTS: Seven studies met the inclusion criteria for the systematic review. All seven studies were included within the meta-analysis for postprandial glucose, four studies were pooled for postprandial insulin and three for SBP. Biomarkers of cardiometabolic health were discussed qualitatively if fewer than three studies measured and reported the variable. A meta-analysis of seven acute, 1-day randomised crossover trials that sampled mixed-sex adults (aged > 18 years) who were predominately overweight or participants with obesity found that standing as an interruption to prolonged sitting significantly reduced postprandial glucose (∆ = - 0.31, 95% CI - 0.60, - 0.03; z = - 2.15, p < 0.04) but had no significant effect on insulin or SBP. Light-intensity walking was shown to significantly attenuate postprandial glucose (∆ = - 0.72, 95% CI - 1.03, - 0.41; z = - 4.57, p < 0.001) and insulin (∆ = - 0.83, 95% CI - 1.18, - 0.48; z = - 4.66, p < 0.001) compared to continued sitting. When comparing light-intensity walking breaks compared to standing breaks a significant reduction in glucose (∆ = - 0.30, 95% CI - 0.52, - 0.08; z = -2.64, p < 0.009) and insulin (∆ = - 0.54, 95% CI - 0.75, - 0.33; z = -4.98, p < 0.001) was observed. Both standing and light-intensity walking showed no effect on SBP. CONCLUSIONS: Frequent short interruptions of standing significantly attenuated postprandial glucose compared to prolonged sitting; however, light-intensity walking was found to represent a superior physical activity break. The feasibility and longitudinal implications of breaking sedentary behaviour with light-intensity walking should be investigated in a free-living setting. REGISTRATION: Not available.

Cross-sectional analysis of levels and patterns of objectively measured sedentary time in adolescent females.

BACKGROUND: Adolescent females have been highlighted as a particularly sedentary population and the possible negative effects of a sedentary lifestyle are being uncovered. However, much of the past sedentary research is based on self-report or uses indirect methods to quantity sedentary time. Total time spent sedentary and the possible intricate sedentary patterns of adolescent females have not been described using objective and direct measure of body inclination. The objectives of this article are to examine the sedentary levels and patterns of a group of adolescent females using the ActivPAL™ and to highlight possible differences in sedentary levels and patterns across the week and within the school day. A full methodological description of how the data was analyzed is also presented. METHODS: One hundred and eleven adolescent females, age 15-18 yrs, were recruited from urban and rural areas in the Republic of Ireland. Participants wore an ActivPAL physical activity monitor for a 7.5 day period. The ActivPAL directly reports total time spent sitting/lying every 15 seconds and accumulation (frequency and duration) of sedentary activity was examined using a customized MATLAB(®) computer software programme. RESULTS: While no significant difference was found in the total time spent sitting/lying over the full 24 hour day between weekday and weekend day (18.8 vs. 18.9 hours; p = .911), significantly more sedentary bouts of 1 to 5 minutes and 21 to 40 minutes in duration were accumulated on weekdays compared to weekend days (p < .001). The mean length of each sedentary bout was also longer (9.8 vs. 8.8 minutes; p < .001). When school hours (9 am-3 pm) and after school hours (4 pm-10 pm) were compared, there was no difference in total time spent sedentary (3.9 hours; p = .796) but the pattern of accumulation of the sedentary time differed. There were a greater number of bouts of > 20 minutes duration during school hours than after school hours (4.7 vs. 3.5 bouts; p < .001) while after school time consisted of shorter bouts < 20 minutes. CONCLUSIONS: School is highlighted as a particularly sedentary setting for adolescent females. Interventions to decrease sedentary time at school and the use of wearable devices which distinguish posture should be encouraged when examining sedentary patterns and behaviors in this population.

Effects of cold water immersion on knee joint position sense in healthy volunteers.

The purpose of this study was to determine the effects of cryotherapy, in the form of cold water immersion, on knee joint position sense. Fourteen healthy volunteers, with no previous knee injury or pre-existing clinical condition, participated in this randomized cross-over trial. The intervention consisted of a 30-min immersion, to the level of the umbilicus, in either cold (14 ± 1 °C) or tepid water (28 ± 1 °C). Approximately one week later, in a randomized fashion, the volunteers completed the remaining immersion. Active ipsilateral limb repositioning sense of the right knee was measured, using weight-bearing and non-weight-bearing assessments, employing video-recorded 3D motion analysis. These assessments were conducted immediately before and after a cold and tepid water immersion. No significant differences were found between treatments for the absolute (P = 0.29), relative (P = 0.21) or variable error (P = 0.86). The average effect size of the outcome measures was modest (range -0.49 to 0.9) and all the associated 95% confidence intervals for these effect sizes crossed zero. These results indicate that there is no evidence of an enhanced risk of injury, following a return to sporting activity, after cold water immersion.

Validation of MET estimates and step measurement using the ActivPAL physical activity logger.

The purpose of this study was to determine the validity of the metabolic equivalent (MET) equation and step rate function of the ActivPAL™ physical activity logger in a group of females. Using a standard treadmill protocol, 62 females aged 15-25 years walked on a treadmill at speeds between 3.2 and 7.0 km · h(-1) while wearing an ActivPAL. Oxygen consumption was measured using expired gas analysis at each speed and METs for each speed were estimated based on each participant's own resting metabolic rate. A sub-set of 18 participants also wore an Actigraph. Results showed that the in-built equation in the ActivPAL significantly underestimated (P < 0.001) METs under treadmill conditions at higher intensities. The ActivPAL equation is based on step rate yet the relationship between counts and measured METs (r = 0.76; P < 0.001) is stronger than that between steps and measured METs (r = 0.59; P < 0.001). Both the ActivPAL and Actigraph step functions showed no significant difference (P > 0.05) to video recorded step rate except at the slowest walking speed where the Actigraph significantly underestimated steps (P < 0.05). The development of a new equation based on the counts-METs relationship that includes a variety of speeds and activities would be useful. The ActivPAL step function performs better than the Actigraph at the slowest walking speed under treadmill conditions.

A risk-prediction model using parameters of maternal body composition to identify gestational diabetes mellitus in early pregnancy.

BACKGROUND: Accurate early risk-prediction for gestational diabetes mellitus (GDM) would target intervention and prevention in women at the highest risk. We evaluated maternal risk-factors and parameters of body-composition to develop a prediction model for GDM in early gestation. METHODS: A prospective observational study was undertaken. Pregnant women aged between 18 and 50 y of age with gestational age between 10 and 16 weeks were included in the study. Women aged ≤18 y, twin-pregnancies, known foetal anomaly or pre-existing condition affecting oedema status were excluded. 8-point-skinfold thickness (SFT), mid-upper-arm-circumference (MUAC), waist, hip, weight and ultrasound measurements of subcutaneous (SAT) and visceral abdominal-adipose (VAT) were measured. Oral-glucose-tolerance-test (OGTT) for GDM diagnosis was undertaken at 28 weeks gestation. Binomial logistic-regression models were used to predict GDM. ROC-analysis determined discrimination and concordance of model and individual variables. RESULTS: 188 women underwent OGTT at ~28 weeks gestation. 20 women developed GDM. BMI (24.7 kg m-2 (±6.1), 29.9 kg m-2 (±7.8), p = 0.022), abdominal SAT(1.32 cm (CI 1.31, 1.53), 1.99 cm (CI 1.64, 2.31), p = 0.027), abdominal VAT(0.78 cm (CI 0.8, 0.96), 1.41 cm (CI 1.11, 1.65), p = 0.002), truncal SFT (84.8 mm (CI 88.2, 101.6), 130.4 mm (CI 105.1, 140.1), p = 0.010), waist (79.8 cm (CI 80.3, 84.1), 90.3 cm (CI 85.9, 96.2), p = 0.006) and gluteal hip (94.3 cm (CI 93.9, 98.0), 108.6 cm (CI 99.9, 111.6), p = 0.023) were higher in GDM vs. non-GDM. After screening variables for inclusion into the multivariate model, family history of diabetes, previous perinatal death, overall insulin resistant condition, abdominal SAT and VAT, 8-point SFT, MUAC and weight were included. The combined multivariate prediction model achieved an excellent level of discrimination, with an AUC of 0.860 (CI 0.774, 0.945) for GDM. CONCLUSIONS: An early gestation risk prediction model, incorporating known risk-factors, and parameters of body-composition, accurately identify pregnant women in their first-trimester who developed GDM later on in gestation. This methodology could be used clinically to identify at-risk pregnancies, and target specific treatment through referred services to those mothers who would most benefit.

Profiling the health-related physical fitness of Irish adolescents: A school-level sociodemographic divide.

BACKGROUND AND AIMS: Examining factors that may explain disparities in fitness levels among youth is a critical step in youth fitness promotion. The purpose of this study was twofold; 1) to examine the influence of school-level characteristics on fitness test performance; 2) to compare Irish adolescents' physical fitness to European norms. METHODS: Adolescents (n = 1215, girls = 609) aged 13.4 years (SD .41) from a randomised sample of 20 secondary schools, stratified for gender, location and educational (dis)advantage, completed a series of field-based tests to measure the components of health-related physical fitness. Tests included: body mass index; 20 metre shuttle run test (20 m SRT); handgrip strength; standing broad jump (SBJ); 4 x 10 metre shuttle run; and back-saver sit-and-reach (BSR). RESULTS: Overall, boys outperformed girls in all tests, aside from the BSR (p < 0.005, t-test, Bonferroni correction). Participants in designated disadvantaged schools had significantly higher body mass index levels (p < 0.001), and significantly lower cardiorespiratory endurance (20 m SRT) (p < 0.001) and muscular strength (handgrip strength) (p = 0.018) levels compared to participants in non-disadvantaged schools. When compared to European norms, girls in this study scored significantly higher in the 20 m SRT, 4 x 10 metre shuttle run and SBJ tests, while boys scored significantly higher in the BSR test (Cohen's d 0.2 to 0.6, p < 0.001). However, European adolescents had significantly higher handgrip strength scores (Cohen's d 0.6 to 0.8, p < 0.001). CONCLUSION: Irish adolescents compared favourably to European normative values across most components of HRPF, with the exception of muscular strength. School socioeconomic status was a strong determinant of performance among Irish adolescents. The contrasting findings for different fitness components reiterate the need for multi-component testing batteries for monitoring fitness in youth.

Use of Compositional Data Analysis to Show Estimated Changes in Cardiometabolic Health by Reallocating Time to Light-Intensity Physical Activity in Older Adults.

BACKGROUND: All physical activity (PA) behaviours undertaken over the day, including sleep, sedentary time, standing time, light-intensity PA (LIPA) and moderate-to-vigorous PA (MVPA) have the potential to influence cardiometabolic health. Since these behaviours are mutually exclusive, standard statistical approaches are unable to account for the impact on time spent in other behaviours. OBJECTIVE: By employing a compositional data analysis (CoDA) approach, this study examined the associations of objectively measured time spent in sleep, sedentary time, standing time, LIPA and MVPA over a 24-h day on markers of cardiometabolic health in older adults. METHODS: Participants (n =366; 64.6 years [5.3]; 46% female) from the Mitchelstown Cohort Rescreen Study provided measures of body composition, blood lipid and markers of glucose control. An activPAL3 Micro was used to obtain objective measures of sleep, sedentary time, standing time, LIPA and MVPA, using a 7-day continuous wear protocol. Regression analysis, using geometric means derived from CoDA (based on isometric log-ratio transformed data), was used to examine the relationship between the aforementioned behaviours and markers of cardiometabolic health. RESULTS: Standing time and LIPA showed diverging associations with markers of body composition. Body mass index (BMI), body mass and fat mass were negatively associated with LIPA (all p <0.05) and positively associated with standing time (all p <0.05). Sedentary time was also associated with higher BMI (p <0.05). No associations between blood markers and any PA behaviours were observed, except for triglycerides, which were negatively associated with standing time (p < 0.05). Reallocating 30 min from sleep, sedentary time or standing time, to LIPA, was associated with significant decreases in BMI, body fat and fat mass. CONCLUSION: This is the first study to employ CoDA in older adults that has accounted for sleep, sedentary time, standing time, LIPA and MVPA in a 24-h cycle. The findings support engagement in LIPA to improve body composition in older adults. Increased standing time was associated with higher levels of adiposity, with increased LIPA associated with reduced adiposity; therefore, these findings indicate that replacing standing time with LIPA is a strategy to lower adiposity.

Tracking of Physical Activity and Sedentary Behavior From Adolescence to Young Adulthood: A Systematic Literature Review.

PURPOSE: The transition from adolescence to young adulthood is categorized by substantial changes in one's activity behaviors, which may have important implications for health. To date, no reviews have systematically investigated the evidence of tracking for both physical activity (PA) and sedentary behavior (SB) specifically during this transition period. METHODS: Web of Science, PubMed, SPORTDiscus, PsycINFO, and CINAHL were searched for articles that examined the tracking of PA and SB in adolescents (aged 9-18 years) through young adulthood (aged 19-25 years) published between the years of 2000 and 2018. Studies were also compared on methodologic quality. RESULTS: Sixteen studies met the inclusion criteria. The tracking correlations for both the frequency and duration of PA were low-to-moderate. Gender differences were observed in the tracking of PA frequency and duration. Studies that examined the tracking of SB were less frequent, making it difficult to determine how SB tracks from adolescence to young adulthood. CONCLUSIONS: Generally, PA was shown to track moderately from adolescence through young adulthood. The lack of studies reporting on the tracking of SB indicates that this area should be a target for future research. Future tracking studies should consider appropriate gold-standard objective methodologies and statistical analysis techniques that report fixed outcomes.