Physical activity patterns in normal, overweight and obese individuals using minute-by-minute accelerometry

Association of Weight Status and Waist Circumference with Physical Activity in people with Schizophrenia Spectrum Disorders and healthy controls

BACKGROUND

Individuals with Schizophrenia Spectrum Disorders (SSD) often suffer from obesity and do limited Physical Activity (PA). PA has many beneficial effects on a variety of somatic and mental variables and it should be strengthened among people with mental disorders. The relationship between Body Mass Index (BMI), Waist Circumference (WC), and PA in this population is poorly understood, with a lack of precise PA assessment. This study investigates the association between BMI, WC, weight, and PA in individuals with SSD and controls using accelerometers.

METHODS

One hundred twenty-six patients with SSD (residents and outpatients) and 110 sex- and age-matched controls were enrolled. Clinical, sociodemographic, and quality-of-life data were collected. PA was measured with a tri-axial ActiGraph GT9X and quantified by Vector Magnitude (VM). Relationships between PA and BMI, WC, and weight changes were analysed using linear regression models.

RESULTS

Patients were more likely to be unmarried, unemployed, and less educated compared to controls (p < 0.001). Residents had more medical comorbidities (p = 0.001), while outpatients had higher BMI, weight, and WC (p < 0.001). Residents reported more severe psychopathology, lower functioning, and greater use of psychopharmacological medications (p < 0.001). Higher PA levels were not significantly associated with lower BMI, WC, or weight. Although not statistically significant, increased PA showed a trend towards lower obesity risk.

CONCLUSIONS

Sociodemographic, medical, and clinical characteristics of individuals with SSD define vulnerability factors that can inform tailored interventions to improve PA.

Macroscopic differences in adult human femora are linked to body mass index

Bone functional adaptation is routinely invoked to interpret skeletal morphology despite ongoing debate regarding the limits of the bone response to mechanical stimuli. The wide variation in human body mass presents an opportunity to explore the relationship between mechanical load and skeletal response in weight-bearing elements. Here, we examine variation in femoral macroscopic morphology as a function of body mass index (BMI), which is used as a metric of load history. A sample of 80 femora (40 female; 40 male) from recent modern humans was selected from the Texas State University Donated Skeletal Collection. Femora were imaged using x-ray computed tomography (voxel size ~0.5 mm), and segmented to produce surface models. Landmark-based geometric morphometric analyses based on the Coherent Point Drift algorithm were conducted to quantify shape. Principal components analyses were used to summarize shape variation, and component scores were regressed on BMI. Within the male sample, increased BMI was associated with a mediolaterally expanded femoral shaft, as well as increased neck-shaft angle and decreased femoral neck anteversion angle. No statistically significant relationships between shape and BMI were found in the female sample. While mechanical stimulus has traditionally been applied to changes in long bong diaphyseal shape it appears that bone functional adaptation may also result in fundamental changes in the shape of skeletal elements.

A Systematic Review of Physical Activity and Sedentary Behavior Patterns in an Osteoarthritic Population

OBJECTIVE

To explore physical activity (PA) and sedentary behaviors (SB) in individuals with lower limb (LL) Osteoarthritis (OA) and the influence of age, sex, and body mass index (BMI) on these behaviors.

DESIGN

Systematic review search: PubMed, Cochrane Library, ScienceDirect, and CINAHL databases were searched from inception until July 2023. Study criteria: Studies that reported quantifiable device-based or self-reported data for PA and SB variables in adults clinically diagnosed with LL OA were included.

DATA SYNTHESIS

A synthesis of PA and SB levels for those diagnosed with LL OA and the influence age, sex, and BMI have on these behaviors.

RESULTS

From the 1930 studies identified through the electronic search process, 48 met the inclusion criteria. PA guidelines were met by 33% of the sample population that measured moderate and moderate to vigorous PA. No studies reported 75 minutes per week or more of vigorous PA. Additionally, 58% of the population reporting SB were sedentary for 8 hours per day or more. Also, increasing age, BMI, and the female sex were identified as negative influences on PA levels. There were numerous methodological inconsistencies in how data were collected and reported, such as various activity monitor cut points for PA and SB bout duration.

CONCLUSION

Adults with LL OA may be at an increased risk of noncommunicable diseases due to low PA and high SB levels. It is important to consider age, sex, and BMI when investigating behavior patterns in those with LL OA.

Associations Between College/University Physical Activity Requirements and Student Physical Activity

Background: Most U.S. college students do not meet physical activity guidelines. Physical activity requirements (PAR) are a proposed solution for increasing undergraduate physical activity. Purpose: To determine whether college/university PAR are associated with undergraduates' self-reported physical activity. Methods: Undergraduate students (N = 383,632) attending colleges and universities taking part in the American College Health Association-National College Health Assessment II survey (2015-2019) self-reported physical activity and demographics. Using websites and course catalogs, researchers coded schools to indicate binary PAR status. Bayesian Hierarchical Logistic Regression was used to determine the percentage of students meeting physical activity guidelines; interactions between PAR status and student characteristics (sex, BMI) were examined. Results: PAR status was positively associated with percent of students meeting physical activity guidelines (PAR: 43.3%, without: 40.5%; difference score 95% Highest Density Interval [HDI; 1.0, 4.5]). A greater percentage of students attending schools with PAR, versus without, met physical activity guidelines across all categories of sex and weight. However, the positive relationship between PAR status and physical activity was stronger among male students (PAR: 46.7%, without: 43.2%; 95% HDI [1.6, 5.4]) compared to female students (PAR: 39.9%, without: 37.9%; 95% HCI [0.2, 3.8]), and among students with underweight (PAR: 39.2%, without: 35.5%; 95% HDI [1.2, 6.3]) or obesity (PAR: 37.1%, without: 33.7%; 95% HDI [1.4, 5.3]) compared to normal weight (PAR: 49.3%, without: 47.4%; 95% HDI [0.1, 3.7]) or overweight (PAR: 47.5%, without: 45.5%; 95% HDI [0.1, 4.0]). Conclusions: PAR are associated with meeting physical activity guidelines, particularly among college/university students with underweight or obesity.

Ensemble of RNN Classifiers for Activity Detection Using a Smartphone and Supporting Nodes

Nowadays, sensor-equipped mobile devices allow us to detect basic daily activities accurately. However, the accuracy of the existing activity recognition methods decreases rapidly if the set of activities is extended and includes training routines, such as squats, jumps, or arm swings. Thus, this paper proposes a model of a personal area network with a smartphone (as a main node) and supporting sensor nodes that deliver additional data to increase activity-recognition accuracy. The introduced personal area sensor network takes advantage of the information from multiple sensor nodes attached to different parts of the human body. In this scheme, nodes process their sensor readings locally with the use of recurrent neural networks (RNNs) to categorize the activities. Then, the main node collects results from supporting sensor nodes and performs a final activity recognition run based on a weighted voting procedure. In order to save energy and extend the network's lifetime, sensor nodes report their local results only for specific types of recognized activity. The presented method was evaluated during experiments with sensor nodes attached to the waist, chest, leg, and arm. The results obtained for a set of eight activities show that the proposed approach achieves higher recognition accuracy when compared with the existing methods. Based on the experimental results, the optimal configuration of the sensor nodes was determined to maximize the activity-recognition accuracy and reduce the number of transmissions from supporting sensor nodes.

Correlations of Accelerometer-Measured Physical Activity with Body Image and Quality of Life among Young and Older Adults: A Pilot Study

Significant evidence suggests that regular physical activity (PA) is correlated with numerous psychological benefits in adults such as improving body image and quality of life. However, this issue has not been differentiated between young and older adults. In addition, most previous studies used a self-reported questionnaire for measuring PA, the objectivity of which is limited in several ways. Hence, by using accelerometer technology for monitoring PA, this study was designed to examine the correlations of PA with body image and quality of life in young and older adults. In this cross-sectional study, we used objective actigraphy and survey data from 147 young and older adults, including 77 young and 70 older adults from Tehran, Iran. To examine our variables and hypothesis, the following instruments were implemented: the Persian version of the Multidimensional Body-Self Relations Questionnaire (MBSRQ), the Persian version of the Quality-of-Life Questionnaire (WHOQOL-BREF), and the ActiGraph wGT3X-BT for measuring PA. An independent t-test and a multivariate regression analysis were used to analyze the data. The weekly PA of both young and older adults was found to be lower than the recommended amount. Young adults engaged in significantly more weekly PA than older adults. For young adults, PA (including MPA, VPA, and MVPA) was generally found to be significantly correlated with body image and quality of life. For older adults, however, we found only significant correlations between VPA and quality of life. These findings indicated that PA is a critical concern in adults, particularly older adults. Accordingly, it is necessary to adopt appropriate strategies to promote an active lifestyle among adults.

Determinants of physical activity among 6856 individuals with diabetes: a nationwide cross-sectional study

INTRODUCTION

The aims of this cross-sectional study were to (1) describe habitual physical activity and adherence to WHO recommendations, and (2) investigate the association of comorbidity, obesity, stress, and health-related quality of life (HRQoL) with moderate to vigorous physical activity (MVPA) among individuals with diabetes.

RESEARCH DESIGN AND METHODS

This study included 6856 participants with diabetes from the Danish National Health Survey from 2017. The primary outcome measure was weekly MVPA. Exposures included self-reported number of conditions, body mass index (BMI), perceived stress, and HRQoL. Mean difference in MVPA across exposures was estimated by multiple linear regression analyses.

RESULTS

Forty per cent of individuals with diabetes were not adherent to WHO recommendations for physical activity. Individuals with diabetes had higher BMI, more comorbidities, higher perceived stress, and lower HRQoL. Individuals with three or more comorbidities were significantly associated with lower weekly MVPA (-0.48 hours/week, 95% CI -0.88 to -0.07) compared with individuals with no comorbidity. Furthermore, overweight or obese (class I-III) individuals engaged in significantly less weekly MVPA (obese class III vs normal weight: -1.98 hours/week, 95% CI -2.49 to -1.47). Higher perceived stress was significantly associated with lower weekly MVPA (-1.76 hours/week, 95% CI -2.18 to -1.34) versus low perceived stress. Finally, having low physical and mental HRQoL was associated with lower weekly MVPA (-0.93 hours/week, 95% CI -1.19 to -0.66 and -0.39 hours/week, 95% CI -0.71 to -0.08 respectively vs moderate or high HRQoL).

CONCLUSIONS

We found that 40% of individuals with diabetes do not engage regularly in adequate physical activity. Comorbidities, higher BMI, higher perceived stress, and lower HRQoL were associated with less engagement in physical activity. This study suggests that subgroups of individuals with diabetes are at higher risk of physical inactivity.

Effect of severe compared with moderate energy restriction on physical activity among postmenopausal female adults with obesity: a prespecified secondary analysis of the Type of Energy Manipulation for Promoting optimum metabolic health and body composition in Obesity (TEMPO) Diet randomized controlled Trial

BACKGROUND

An under-explored strategy for increasing physical activity is the dietary treatment of obesity, but empirical evidence is lacking.

OBJECTIVES

We aimed to compare the effects of weight loss via severe as opposed to moderate energy restriction on physical activity over 36 mo.

METHODS

A total of 101 postmenopausal female adults (45-65 y, BMI 30-40 kg/m2, <180 min/wk of structured exercise) were randomly assigned to either 12 mo of moderate energy restriction (25%-35% of energy requirement) with a food-based diet, or a severe intervention involving 4 mo of severe energy restriction (65%-75% of energy requirement) with a total meal replacement diet, followed by 8 mo of moderate energy restriction. Physical activity was encouraged, but no tailored or supervised exercise prescription was provided. Physical activity was assessed with an accelerometer worn for 7 d before baseline (0 mo) and 0.25, 1, 4, 6, 12, 24, and 36 mo after intervention commencement.

RESULTS

Compared with the moderate group, the severe group exhibited greater mean: total volume of physical activity; duration of moderate-to-vigorous-intensity physical activity (MVPA); duration of light-intensity physical activity; step counts, as well as lower mean duration of sedentary time. All these differences (except step counts) were apparent at 6 mo [e.g., 1006 metabolic equivalent of task (MET)-min/wk; 95% CI: 564, 1449 MET-min/wk for total volume of physical activity], and some were also apparent at 4 and/or 12 mo. There were no differences between groups in the 2 other outcomes investigated (self-efficacy to regulate exercise; and proportion of participants meeting the WHO's 2020 Physical Activity Guidelines for MVPA). When the analyses were adjusted for weight at each time point, the differences between groups were either attenuated or abolished.

CONCLUSIONS

Among female adults with obesity, including a dietary component to reduce excess body weight-notably one involving severe energy restriction-could potentially enhance the effectiveness of physical activity interventions.This trial was registered at www.anzctr.org.au as ACTRN12612000651886.

Relations Between BMI Trajectories and Habitual Physical Activity Measured by a Smartwatch in the Electronic Cohort of the Framingham Heart Study: Cohort Study

BACKGROUND

The prevalence of obesity is rising. Most previous studies that examined the relations between BMI and physical activity (PA) measured BMI at a single timepoint. The association between BMI trajectories and habitual PA remains unclear.

OBJECTIVE

This study assesses the relations between BMI trajectories and habitual step-based PA among participants enrolled in the electronic cohort of the Framingham Heart Study (eFHS).

METHODS

We used a semiparametric group-based modeling to identify BMI trajectories from eFHS participants who attended research examinations at the Framingham Research Center over 14 years. Daily steps were recorded from the smartwatch provided at examination 3. We excluded participants with <30 days or <5 hours of smartwatch wear data. We used generalized linear models to examine the association between BMI trajectories and daily step counts.

RESULTS

We identified 3 trajectory groups for the 837 eFHS participants (mean age 53 years; 57.8% [484/837] female). Group 1 included 292 participants whose BMI was stable (slope 0.005; P=.75), group 2 included 468 participants whose BMI increased slightly (slope 0.123; P<.001), and group 3 included 77 participants whose BMI increased greatly (slope 0.318; P<.001). The median follow-up period for step count was 516 days. Adjusting for age, sex, wear time, and cohort, participants in groups 2 and 3 took 422 (95% CI -823 to -21) and 1437 (95% CI -2084 to -790) fewer average daily steps, compared with participants in group 1. After adjusting for metabolic and social risk factors, group 2 took 382 (95% CI -773 to 10) and group 3 took 1120 (95% CI -1766 to -475) fewer steps, compared with group 1.

CONCLUSIONS

In this community-based eFHS, participants whose BMI trajectory increased greatly over time took significantly fewer steps, compared with participants with stable BMI trajectories. Our findings suggest that greater weight gain may correlate with lower levels of step-based physical activity.

Relationship Between Circadian Strain, Light Exposure, and Body Mass Index in Rural and Urban Quilombola Communities

Industrialization has greatly changed human lifestyle; work and leisure activities have been moved indoors, and artificial light has been used to illuminate the night. As cyclic environmental cues such as light and feeding become weak and/or irregular, endogenous circadian systems are increasingly being disrupted. These disruptions are associated with metabolic dysfunction, possibly contributing to increased rates of overweight and obesity worldwide. Here, we aimed to investigate how activity-rest rhythms, patterns of light exposure, and levels of urbanization may be associated with body mass index (BMI) in a sample of rural and urban Quilombola communities in southern Brazil. These are characterized as remaining social groups who resisted the slavery regime that prevailed in Brazil. Quilombola communities were classified into five groups according to their stage of urbanization: from rural areas with no access to electricity to highly urbanized communities. We collected anthropometric data to calculate BMI, which was categorized as follows: from ≥ 18.5 kg/m² to < 25 kg/m² = normal weight; from ≥ 25 kg/m² to < 30 kg/m² = overweight; and ≥ 30 kg/m² = obese. Subjects were asked about their sleep routines and light exposure on workdays and work-free days using the Munich Chronotype Questionnaire (N = 244 included). In addition, we analyzed actimetry data from 121 participants with seven consecutive days of recordings. Living in more urbanized areas and higher intradaily variability (IV) of activity-rest rhythms were associated with an increased risk of belonging to the overweight or obese group, when controlling for age and sex. These findings are consistent with preclinical data and point to potential strategies in obesity prevention and promotion of healthy metabolic profiles.

Physical activity, body mass index, and blood progranulin in older adults: cross-sectional associations in the MAPT study

Physical activity (PA) has been shown to moderate the negative effects of obesity on pro-inflammatory cytokines but its relationship with the adipokine progranulin (PGRN) remains poorly investigated. This study aimed to examine the cross-sectional main and interactive associations of body mass index (BMI) and PA level with circulating PGRN in older adults. Five-hundred and twelve subjects aged 70 years and over involved in the Multidomain Alzheimer Prevention Trial (MAPT) Study who underwent plasma PGRN measurements (ng/ml) were included. Self -reported PA levels were assessed using questionnaires. People were classified into three BMI categories: normal weight, overweight or obesity. Further categorization using PA tertiles was used to define highly active, moderately active and low active individuals. Multiple linear regressions were performed in order to test the associations of BMI, PA level, and their interaction with PGRN levels. Multiple linear regressions adjusted by age, sex, diabetes mellitus status, total cholesterol, creatinine level and MAPT group demonstrated significant interactive associations of BMI status and continuous PA such that in people without obesity, higher PA levels were associated with lower PGRN concentrations, while an opposite pattern was found in individuals with obesity. In addition, continuous BMI was positively associated with circulating PGRN in highly active individuals but not in their less active peers. This cross-sectional study demonstrated reverse patterns in older adults with obesity compared to those without obesity regarding the relationships between PA and PGRN levels. Longitudinal and experimental investigations are required to understand the mechanisms that underlie the present findings.

Predictors for physical activity and its change after active physical therapy in people with spinal pain and insomnia: Secondary analysis of a randomized controlled trial

BACKGROUND

In healthy people and people with nonspecific chronic spinal pain (nCSP) and/or insomnia, participation in physical activity on a regular basis has several physical and psychological health benefits. However, people with chronic conditions often tend to reduce physical activity participation which can lead to deconditioning over time. Currently, there are no known predictors for an (in)active lifestyle (before and after physical therapy treatment) in people with chronic spinal pain and comorbid insomnia.

OBJECTIVE

To examine predictors of pre-treatment moderate-to-vigorous physical activity (MVPA) and to examine determinants for a change in MVPA in response to 14-weeks of active physical therapy treatment in people with nonspecific chronic spinal pain (nCSP) and comorbid insomnia.

METHODS

Baseline data and post-treatment data were analyzed for 66 participants. A linear multiple regression analysis was conducted to examine which factors predict MVPA at baseline. Linear mixed-effects modeling was used to identify determinants for change in MVPA in response to an active physical therapy treatment.

RESULTS

Physical fatigue (b = -0.9; 95%CI: -1.59, -0.15), less limitations in functioning as a result of emotional problems (b = 0.1; 95%CI: 0.03, 0.10), mental fatigue (b = -1.0; 95%CI: -1.67, -0.43), lower general sleep quality (b= 0.7; 95%CI: 0.22, 1.17), and body mass index (b = -0.5; 95%CI: -0.93, -0.16) were significant predictors of baseline MVPA. The regression model explained 33.3% of the total variance in baseline MVPA. The change of MVPA in response to the treatment ranged from a decrease of 17.5 to an increase of 16.6 hours per week. No determinants for change in MVPA after treatment could be identified.

CONCLUSION

People with nCSP and comorbid insomnia are more likely to engage in MVPA if they report, at baseline, lower sleep quality, fewer limitations in functioning resulting from emotional problems, lower body mass index, as well as less physical and mental fatigue.

Changes in leisure time physical activity unrelated to subsequent body weight changes, but body weight changes predicted future activity

Physical activity and obesity are known to be associated. We investigated whether a change in leisure time physical activities (LTPA) predicts a subsequent weight change, or vice versa.We used data from a longitudinal study among Danish adults surveyed in 1983-1984, 1987-1988, and 1993-1994. Between two sequential surveys, the change in LTPA was grouped as no change, became less or more active; the change in body weight was defined as no change, lost or gained of more than one body mass index (BMI) unit.Among 2386 adults, change in LTPA was not associated with subsequent weight change. However, a loss in body weight (BMI change < -1 unit) was associated with subsequent either becoming less [OR = 1.49, 95% CI (1.03-2.15)] or borderline more active [OR = 1.37, 95% CI (0.99-1.90)]. Subgroup analyses showed particularity among females that a loss in body weight was associated with subsequent becoming more active [OR = 1.83, 95% CI (1.15-2.89)].Our results suggest that change in LTPA is unrelated to subsequent weight change, but loss in body weight seems related to subsequent more active among female adults.

A systematic review of smartphone-based human activity recognition methods for health research

Smartphones are now nearly ubiquitous; their numerous built-in sensors enable continuous measurement of activities of daily living, making them especially well-suited for health research. Researchers have proposed various human activity recognition (HAR) systems aimed at translating measurements from smartphones into various types of physical activity. In this review, we summarized the existing approaches to smartphone-based HAR. For this purpose, we systematically searched Scopus, PubMed, and Web of Science for peer-reviewed articles published up to December 2020 on the use of smartphones for HAR. We extracted information on smartphone body location, sensors, and physical activity types studied and the data transformation techniques and classification schemes used for activity recognition. Consequently, we identified 108 articles and described the various approaches used for data acquisition, data preprocessing, feature extraction, and activity classification, identifying the most common practices, and their alternatives. We conclude that smartphones are well-suited for HAR research in the health sciences. For population-level impact, future studies should focus on improving the quality of collected data, address missing data, incorporate more diverse participants and activities, relax requirements about phone placement, provide more complete documentation on study participants, and share the source code of the implemented methods and algorithms.

The Relationship Between Habitual Physical Activity, Sitting Time, and Cognitive Function in Young Adult Women

BACKGROUND

There is evidence that physical activity (PA), sitting time, and obesity may impact cognition, but few studies have examined this in young women.

METHODS

Healthy women (18-35 y), without conditions that impair cognition, were recruited for this cross-sectional study. Participants completed anthropometric and validated computerized cognitive assessments (IntegNeuro™). Performance on 5 cognitive domains (impulsivity, attention, information processing, memory, and executive function) was reported as z scores. Sitting hours and weekly PA calculated from time in low-, moderate-, and high-intensity activity were obtained via the International Physical Activity Questionnaire. Analysis of variance/analysis of covariance, chi-square, and linear regression were used.

RESULTS

299 (25.9 [5.1] y) women (low PA = 19%; moderate PA = 40%; high PA = 41%) participated. High PA women had lower body mass index (high PA = 26.1 [6.5]; moderate PA = 30.0 [8.7]; low PA = 31.0 [11.1] kg/m2; P < .001) and less sitting time (high PA = 6.6 [3.1]; moderate PA = 7.7 [2.8]; low PA = 9.3 [3.6] hr/weekday; P < .0001). Cognitive function was within normal ranges and did not differ between any PA groups (P = .42). Adjusting for body mass index, C-reactive protein, or sitting hours did not alter results. Weak correlations were found between time in high-intensity activity and impulsivity (b = 0.12, r2 = .015; P = .04), and between sitting hours and information processing efficiency (b = -0.18, r2 = .03; P = .002). Valuesare presented as mean (SD).

CONCLUSIONS

Cognitive function was within the normal range, regardless of PA or sitting time.

Greater risk of all-cause revisions and complications for obese patients in 3 106 381 total knee arthroplasties: a meta-analysis and systematic review

BACKGROUND

Obesity is a major public health issue and has considerable implications on outcomes of total knee arthroplasty (TKA). However, there has been conflicting evidence and conclusions on the effects of obesity on TKA. This meta-analysis compares the outcomes, complications, and peri-operative parameters of TKA in the obese (body mass index [BMI] ≥ 30 kg/m² ) versus non-obese (BMI < 30 kg/m² ) population as well as subgroup analysis of morbidly obese (BMI ≥ 40 kg/m² ) versus non-obese population.

METHODS

A meta-analysis was conducted with a multi-database search according to PRISMA guidelines on 12 September 2019. Data from all published literature meeting inclusion criteria were extracted and analysed.

RESULTS

Ninety-one studies were included, consisting of 917 447 obese and 2 188 834 non-obese TKA. Obese patients had higher risk of all-cause revisions (odds ratio [OR] = 1.15, 95% CI: 1.08-1.24, p < 0.0001), all complications (OR = 1.21, 95% CI: 1.06-1.38, p = 0.004), deep infections (OR = 1.47, 95% CI: 1.27-1.69, p < 0.0001), superficial infections (OR = 1.59, 95% CI: 1.32-1.91, p < 0.0001), wound dehiscence (OR = 1.46, 95% CI: 1.24-1.72, p < 0.0001) and readmissions (OR = 1.21, 95% CI: 1.05-1.40, p = 0.009). Subgroup analysis of morbidly obese patients revealed greater risks of all-cause revisions (OR = 1.25, 95% CI: 1.10-1.43, p = 0.0009), deep infections (OR = 1.98, 95% CI: 1.05-3.75, p = 0.04), superficial infections (OR = 2.44, 95% CI: 2.08-2.88, p < 0.0001) and readmissions (OR = 1.33, 95% CI: 1.20-1.47, p < 0.0001). No analysis was performed on patient reported outcome measures due to heterogeneous reporting methods.

CONCLUSION

Obese and morbidly obese patients have higher risks of revisions and infections post TKA. Surgeons should counsel patients of these risks during the informed consenting process and adopt preventative strategies into clinical practice to reduce risks where possible. In conclusion, obesity is a significant, modifiable risk factor for increased complications following TKA.

Physical Activity Monitoring Using a Fitbit Device in Ischemic Stroke Patients: Prospective Cohort Feasibility Study

Background

Continuous tracking of ambulatory activity in real-world settings using step activity monitors has many potential uses. However, feasibility, accuracy, and correlation with performance measures in stroke patients have not been well-established.

Objective

The primary study objective was to determine adherence with wearing a consumer-grade step activity monitor, the Fitbit Charge HR, in home-going ischemic stroke patients during the first 90 days after hospital discharge. Secondary objectives were to (1) determine accuracy of step counts of the Fitbit Charge HR compared with a manual tally; (2) calculate correlations between the Fitbit step counts and the mobility performance scores at discharge and 30 days after stroke; (3) determine variability and change in weekly step counts over 90 days; and (4) evaluate patient experience with using the Fitbit Charge HR poststroke.

Methods

A total of 15 participants with recent mild ischemic stroke wore a Fitbit Charge HR for 90 days after discharge and completed 3 mobility performance tests from the National Institutes of Health Toolbox at discharge and Day 30: (1) Standing Balance Test, (2) 2-Minute Walk Endurance Test, and (3) 4-Meter Walk Gait Speed Test. Accuracy of step activity monitors was assessed by calculating differences in steps recorded on the step activity monitor and a manual tally during 2-minute walk tests.

Results

Participants had a mean age of 54 years and a median modified Rankin scale score of 1. Mean daily adherence with step activity monitor use was 83.6%. Mean daily step count in the first week after discharge was 4376. Daily step counts increased slightly during the first 30 days after discharge (average increase of 52.5 steps/day; 95% CI 32.2-71.8) and remained stable during the 30-90 day period after discharge. Mean step count difference between step activity monitor and manual tally was –4.8 steps (–1.8%). Intraclass correlation coefficients for step counts and 2-minute walk, standing balance, and 4-meter gait speed at discharge were 0.41 (95% CI –0.14 to 0.75), –0.12 (95% CI –0.67 to 0.64), and 0.17 (95% CI –0.46 to 0.66), respectively. Values were similarly poor at 30 days.

Conclusions

The use of consumer-grade Fitbit Charge HR in patients with recent mild stroke is feasible with reasonable adherence and accuracy. There was poor correlation between step counts and gait speed, balance, and endurance. Further research is needed to evaluate the association between step counts and other outcomes relevant to patients, including patient-reported outcomes and measures of physical function.

Morning resolutions, evening disillusions: Theories of willpower affect how health behaviours change across the day

People may be more or less vulnerable to changes in self-control across the day, depending on whether they believe willpower is more or less limited. Limited willpower beliefs might be associated with steeper decreases in self-control across the day, which may result in less goal-consistent behaviour by the evening. Community members with health goals (Sample 1; N = 160; 1814 observations) and students (Sample 2; N = 162; 10,581 observations) completed five surveys per day for one to three weeks, reporting on their recent physical activity, snacking, subjective state, and health intentions. In both samples, more limited willpower beliefs were associated with less low- and moderate-intensity physical activity, particularly later in the day. Limited willpower beliefs were also associated with more snacking in the evenings (Sample 1) or overall (Sample 2). These behavioural patterns were mediated by differential changes in self-efficacy and intentions across the course of the day (in Sample 1), and the above patterns of low- and moderate-physical intensity held after controlling for related individual differences, including trait self-control and chronotype (in Sample 2). Overall, more limited willpower theories were associated with decreasing goal-consistent behaviour as the day progressed, alongside decreasing self-efficacy and weakening health-goal intentions.

The accumulation of, and associations between, nurses' activity levels within their shift in the emergency department

The aim of this study was to examine emergency nurses' activity levels and associations between hourly activity levels within-shifts. Fifty emergency nurses (45 females, 5 males) wore ActiGraph accelerometers and completed work diaries for up to 4 weeks. A sub-group (n = 42) also wore activPALs. Multilevel analyses examined temporal associations between hourly periods. In any hourly period, increased time spent in moderate- to vigorous-intensity physical activity (MVPA) was associated with less time spent in MVPA in the following hourly period. In any afternoon hourly period, increased time spent in MVPA was associated with more time spent in light-intensity physical activity in the following hourly period. No other associations were significant. Emergency nurses maintain activity levels within-shifts, except when more time spent in MVPA was associated with less time spent in MVPA in the following hour; a potential recovery strategy. Future research should determine how emergency nurses maintain their activity levels within-shifts. Practitioner Summary: Emergency nursing is physically demanding; however, it is unknown how active they are during hourly periods within-shifts. Emergency nurses' activity levels were maintained within hourly periods of a shift. Except for an increase in MVPA in 1 h was associated with a decrease in MVPA in the following hour. Abbreviations: CPR: cardiopulmonary resusitation; LPA: light-intensity physical activity; MPA: moderate-intenisty physical activity; MVPA: moderate- to vigorous-intensity physical activity; SED: sedentary.

Associations Between Physical Activity Intensities and Physical Function in Stroke Survivors

PURPOSE

Impairment caused by stroke is a major cause of disablement in older adults. Physical activity has been shown to improve physical functioning; however, little research has been done to explore how physical activity of different intensities may affect physical function among stroke survivors. The purpose of this study was to examine the patterns of accelerometer-measured physical activity and the relationship between physical activity intensities and objective physical functioning and perceived functional limitations in stroke survivors.

METHODS

Stroke survivors (N = 30, mean age = 61.77 ± 11.17) completed the Short Physical Performance Battery and the Late-Life Function and Disability Instrument. Physical activity intensities were measured objectively using a 7-day actigraph accelerometer wear period and scored using the National Health and Nutrition Examination Survey cutoffs for sedentary (counts/minute ≤100), light (counts/minute 101-2019), and moderate to vigorous (moderate to vigorous physical activity counts/minute ≥2020) activity.

RESULTS

Multiple linear regressions controlling for age and time since stroke demonstrated that higher levels of moderate to vigorous physical activity predicted better Short Physical Performance Battery performance (β = .43, P = 0.04). For self-reported physical function, light physical activity predicted better basic lower limb function (β = .45, P = 0.009), better advanced lower limb function (β = .53, P = 0.003), better upper limb function (β = .37, P = 0.04), and higher total function score (β = .52, P = 0.002) on the Late-Life Function and Disability Instrument.

CONCLUSIONS

These findings suggest that light activity as well as moderate to vigorous physical activity may contribute to better physical functioning in stroke survivors. Although moderate to vigorous physical activity significantly predicted the objective measure of physical function (Short Physical Performance Battery), light physical activity consistently predicted higher scores on all subscales of the Late-Life Function and Disability Instrument. Disabilities resulting from stroke may limit this population from engaging in moderate to vigorous physical activity, and these findings highlight the importance of light physical activity, which may offer similar perceived functional benefits. Future studies should focus on development of effective exercise interventions for stroke survivors by incorporating and comparing both moderate to vigorous physical activity and light-intensity physical activity.

Impact of a group-based intervention program on physical activity and health-related outcomes in worksite settings

Background

The benefits of physical activity (PA) have been well documented, and the worksite is a promising setting for PA promotion. The aims of this study were as follows: 1. To evaluate the effect of a group-based worksite intervention on PA and health-related outcomes by using pedometers. 2. To examine the associations between the change in vigorous physical activity (VPA)/moderate physical activity (MPA)/walking and health related outcomes.

Methods

A total of 398 participants (221 in the intervention group (IG) and 177 in the control group (CG)) from 17 worksites were recruited for a prospective self-controlled trial of a worksite physical activity intervention program in China. In the IG, a pedometer was utilized to self-monitor the PA, together with group competition, goal setting, and other incentives. No intervention was applied to the CG. Physical activity, sedentary behavior, and health-related outcomes were measured at baseline and immediately after the 100-day period intervention.

Results

A total of 262 participants completed the program (68.3% adherence). Adherence in the intervention group was 67.9% (n = 150/221). Improvements between baseline and follow-up among intervention participants were observed in the following parameters: VPA (+ 109.7 METs/week; p < 0.05), walking (+ 209.2 METs/week; p < 0.01), systolic blood pressure (SBP; − 2.1 mmHg; p < 0.01), waist circumference (WC; − 2.3 cm; p < 0.01), body fat percentage (BF); − 1.0%; p < 0.01), and body mass index (BMI; − 0.5 kg/m²; p < 0.01). VPA was related to changes in body fat percentage (p < 0.05) and body mass index (p < 0.05).

Conclusion

This integrated group-based intervention program contributed to comprehensive improvement in health-related outcomes. The study was useful for establishing associations between change in VPA/MPA/walking and health-related outcomes in a natural setting. Long-term evaluation is required to examine the potential of such an integrated intervention to promote PA.

Registration

This study was prospectively registered in the Chinese Clinical Trial Registry. Trial registration number: ChiCTR-1,800,015,529. Date of registration: April 5, 2018.

Physical activity and risk of cardiovascular disease by weight status among U.S adults

PURPOSE

We sought to determine whether the association between physical activity and 10-year cardiovascular disease (CVD) risk varies among normal weight, overweight, and obese adults in a nationally-representative sample of the United States.

METHODS

Data were from the National Health and Nutrition Examination Survey 2007-2016. A subset of 22,476 participants aged 30-64 years was included with no CVD history. Physical activity level was self-reported and stratified into sedentary (0 min/week), inactive (1-149 mins/week), or active (≥150 mins/week) of moderate or vigorous activities. Framingham risk scores were classified as low/intermediate (<20%) or high 10-year CVD risk (≥20%).

RESULTS

The average age of the population was 45.9 years, 52.3% were female, 33.6% were overweight (BMI 25.0-29.9kg/m2), and 35.7% were obese (BMI≥30kg/m2). Individuals who were overweight and obese had a higher 10-year CVD risk compared to those with normal weight (9.5 vs. 10.1 vs. 6.3%, P<0.001). The association of physical activity and high 10-year CVD risk differed by weight status. Among overweight and obese adults, individuals engaged in any physical activity had lower odds ofhigh 10-year CVD risk compared to sedentary individuals (overweight: OR active = 0.48, 95% CI: 0.36-0.64; OR inactive = 0.53, 95% CI: 0.45-0.86; obese: OR active = 0.50, 95% CI: 0.37-0.68; OR inactive = 0.66, 95% CI: 0.49-0.89). Among normal weight adults, individuals who were physically active had lower odds of high 10-year CVD risk (OR = 0.59, 95% CI: 0.28-0.87). When compared the joint effects of physical activity level and weight status, physical activity was associated with a larger magnitude of reduced odds of 10-year CVD risk than weight status.

CONCLUSION

Participation in any level of physical activity is associated with a lower 10-year CVD risk for overweight and obese adults. Future studies are needed to identify effective modes and doses of exercise that offer optimal CVD benefits for populations with different weight statuses.

Hour-by-hour physical activity patterns of adults aged 45-65 years: a cross-sectional study

Background

Limited information exists on hour-by-hour physical activity (PA) patterns among adults aged 45–65 years. Therefore, this study aimed to distinguish typical hour-by-hour PA patterns, and examined which individuals typically adopt certain PA patterns.

Methods

Accelerometers measured light and moderate-vigorous PA. GIS-data provided proportions of land use within an 800 and 1600 m buffer around participant’s homes. Latent class analyses were performed to distinguish PA patterns and groups of individuals with similar PA patterns.

Results

Four PA patterns were identified: a morning light PA pattern, a mid-day moderate-vigorous PA pattern, an overall inactive pattern and an overall active pattern. Groups of individuals with similar PA patterns differed in ethnicity, dog ownership, and the proportion of roads, sports terrain, larger green and blue space within their residential areas.

Conclusions

Four typical hour-by-hour PA patterns, and three groups of individuals with similar patterns were distinguished. It is this combination that can substantially contribute to the development of more tailored policies and interventions. PA patterns were only to a limited extent associated with personal and residential characteristics, suggesting that other factors such as work time regimes, family life and leisure may also have considerable impact on the distribution of PA throughout the day.

Neighbourhood greenspace and physical activity and sedentary behaviour among older adults with a recent diagnosis of type 2 diabetes: a prospective analysis

OBJECTIVES

Greenspace is one of the important factors that can promote an active lifestyle. Thus, greener surroundings may be a motivating factor for people with newly diagnosed diabetes to engage in more physical activity. Given that diagnosis of type 2 diabetes (T2D) may serve as a window opportunity for behavioural modification, we hypothesise that the association between neighbourhood greenspace and physical activity among people with newly diagnosed T2D may be greater than those not diagnosed with T2D. The aim of this study was to investigate the association between access to greenspace and changes in physical activity and sedentary behaviour, and whether these associations differed by T2D.

DESIGN

Prospective cohort.

SETTING

New South Wales, Australia.

METHODS

We used self-reported information from the New South Wales 45 and Up Study (baseline) and a follow-up study. Information on sitting, walking and moderate to vigorous physical activity was used as outcomes. The proportion of greenspace within 500 m, 1 km and 2 km road network buffers around participant's residential address was generated as a proxy measure for access to greenspace. The association between the access to greenspace and the outcomes were explored among the newly diagnosed T2D group and those without T2D.

RESULTS

Among New T2D, although no significant changes were found in the amount of walking with the percentage of greenspace, increasing trends were apparent. There was no significant association between the percentage of greenspace and changes in amount of moderate to vigorous physical activity (MVPA). Among No T2D, there were no significant associations between the amount of MVPA and walking, and percentage of greenspace. For changes in sitting time, there were no significant associations with percentage of greenspace regardless of buffer size.

CONCLUSIONS

In this study, there was no association between access to greenspace at baseline and change in walking, MVPA and sitting time, regardless of T2D status.

Association Between Idiopathic Intracranial Hypertension and Risk of Cardiovascular Diseases in Women in the United Kingdom

IMPORTANCE

Cardiovascular disease (CVD) risk has not been previously evaluated in a large matched cohort study in idiopathic intracranial hypertension (IIH).

OBJECTIVES

To estimate the risk of composite cardiovascular events, heart failure, ischemic heart disease, stroke/transient ischemic attack (TIA), type 2 diabetes, and hypertension in women with idiopathic intracranial hypertension and compare it with the risk in women, matched on body mass index (BMI) and age, without the condition; and to evaluate the prevalence and incidence of IIH.

DESIGN, SETTING, AND PARTICIPANTS

This population-based matched controlled cohort study used 28 years of data, from January 1, 1990, to January 17, 2018, from The Health Improvement Network (THIN), an anonymized, nationally representative electronic medical records database in the United Kingdom. All female patients aged 16 years or older were eligible for inclusion. Female patients with IIH (n = 2760) were included and randomly matched with up to 10 control patients (n = 27 125) by BMI and age.

MAIN OUTCOMES AND MEASURES

Adjusted hazard ratios (aHRs) of cardiovascular outcomes were calculated using Cox regression models. The primary outcome was a composite of any CVD (heart failure, ischemic heart disease, and stroke/TIA), and the secondary outcomes were each CVD outcome, type 2 diabetes, and hypertension.

RESULTS

In total, 2760 women with IIH and 27 125 women without IIH were included. Age and BMI were similar between the 2 groups, with a median (interquartile range) age of 32.1 (25.6-42.0) years in the exposed group and 32.1 (25.7-42.1) years in the control group; in the exposed group 1728 women (62.6%) were obese, and in the control group 16514 women (60.9%) were obese. Higher absolute risks for all cardiovascular outcomes were observed in women with IIH compared with control patients. The aHRs were as follows: composite cardiovascular events, 2.10 (95% CI, 1.61-2.74; P < .001); heart failure, 1.97 (95% CI, 1.16-3.37; P = .01); ischemic heart disease, 1.94 (95% CI, 1.27-2.94; P = .002); stroke/TIA, 2.27 (95% CI, 1.61-3.21; P < .001); type 2 diabetes, 1.30 (95% CI, 1.07-1.57; P = .009); and hypertension, 1.55 (95% CI, 1.30-1.84; P < .001). The incidence of IIH in female patients more than tripled between 2005 and 2017, from 2.5 to 9.3 per 100 000 person-years. Similarly, IIH prevalence increased in the same period, from 26 to 79 per 100 000 women. Incidence increased markedly with BMI higher than 30.

CONCLUSIONS AND RELEVANCE

Idiopathic intracranial hypertension in women appeared to be associated with a 2-fold increase in CVD risk; change in patient care to modify risk factors for CVD may reduce long-term morbidity for women with IIH and warrants further evaluation.

Seasonality of physical activity and its association with socioeconomic and health factors among urban-dwelling adults of Kaunas, Lithuania

BACKGROUND

Physical activity (PA) has been declining dramatically over time in many countries worldwide. The decrease of PA levels affects a person's health and quality of life as it is a significant risk factor for many noncommunicable diseases. Understanding the factors that determine PA is particularly important in promoting greater PA in adults and reducing the risk of diseases associated with physical inactivity. This study investigated associations of seasonal PA levels with socioeconomic and health factors among adults.

METHODS

A cross-sectional study included 1111 participants of Kaunas city, Lithuania who completed a questionnaire about PA and mobility behaviour, socioeconomic, health and demographic factors. Commuting PA and sufficient PA (sPA) on weekdays and weekends in the summer and winter seasons was investigated in this study. Data on daily commuting duration and forms of transportation were collected using a questionnaire survey. Daily commuting was categorized into two categories: 1) using motorized transportation or walking or cycling 0 to 29 min, 2) and walking or cycling for 30 min or more.

RESULTS

Our findings showed significant seasonal impact on PA levels. The results revealed that employment status was significantly associated with PA. Unemployed individuals were 2 times more likely to engage in sPA in winter and almost 3 times in summer compared to workers.

CONCLUSIONS

Our findings suggest the importance of considering environmental, socioeconomic and health factors when assessing PA. Promoting PA through active commuting is an important part of a healthy lifestyle and strategies to support the implementation of health-promoting policies and practices are needed.

Obesity modifies the stoichiometry of mitochondrial proteins in a way that is distinct to the subcellular localization of the mitochondria in skeletal muscle

BACKGROUND

Skeletal muscle mitochondrial content and function appear to be altered in obesity. Mitochondria in muscle are found in well-defined regions within cells, and they are arranged in a way that form distinct subpopulations of subsarcolemmal (SS) and intermyofibrillar (IMF) mitochondria. We sought to investigate differences in the proteomes of SS and IMF mitochondria between lean subjects and subjects with obesity.

METHODS

We performed comparative proteomic analyses on SS and IMF mitochondria isolated from muscle samples obtained from lean subjects and subjects with obesity. Mitochondria were isolated using differential centrifugation, and proteins were subjected to label-free quantitative tandem mass spectrometry analyses. Collected data were evaluated for abundance of mitochondrial proteins using spectral counting. The Reactome pathway database was used to determine metabolic pathways that are altered in obesity.

RESULTS

Among proteins, 73 and 41 proteins showed different (mostly lower) expression in subjects with obesity in the SS and IMF mitochondria, respectively (false discovery rate-adjusted P ≤ 0.05). We specifically found an increase in proteins forming the tricarboxylic acid cycle and electron transport chain (ETC) complex II, but a decrease in proteins forming protein complexes I and III of the ETC and adenosine triphosphate (ATP) synthase in subjects with obesity in the IMF, but not SS, mitochondria. Obesity was associated with differential effects on metabolic pathways linked to protein translation in the SS mitochondria and ATP formation in the IMF mitochondria.

CONCLUSIONS

Obesity alters the expression of mitochondrial proteins regulating key metabolic processes in skeletal muscle, and these effects are distinct to mitochondrial subpopulations located in different regions of the muscle fibers.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT01824173).

Mitochondrial ATP synthase β-subunit production rate and ATP synthase specific activity are reduced in skeletal muscle of humans with obesity

NEW FINDINGS

What is the central question of this study? Humans with obesity have lower ATP synthesis in muscle along with lower content of the β-subunit of the ATP synthase (β-F1-ATPase), the catalytic component of the ATP synthase. Does lower synthesis rate of β-F1-ATPase in muscle contribute to these responses in humans with obesity? What is the main finding and its importance? Humans with obesity have a lower synthesis rate of β-F₁ -ATPase and ATP synthase specific activity in muscle. These findings indicate that reduced production of subunits forming the ATP synthase in muscle may contribute to impaired generation of ATP in obesity.

ABSTRACT

The content of the β-subunit of the ATP synthase (β-F₁ -ATPase), which forms the catalytic site of the enzyme ATP synthase, is reduced in muscle of obese humans, along with a reduced capacity for ATP synthesis. We studied 18 young (37 ± 8 years) subjects of which nine were lean (BMI = 23 ± 2 kg m^-2 ) and nine were obese (BMI = 34 ± 3 kg m^-2 ) to determine the fractional synthesis rate (FSR) and gene expression of β-F₁ -ATPase, as well as the specific activity of the ATP synthase. FSR of β-F₁ -ATPase was determined using a combination of isotope tracer infusion and muscle biopsies. Gene expression of β-F₁ -ATPase and specific activity of the ATP synthase were determined in the muscle biopsies. When compared to lean, obese subjects had lower muscle β-F₁ -ATPase FSR (0.10 ± 0.05 vs. 0.06 ± 0.03% h^-1 ; P < 0.05) and protein expression (P < 0.05), but not mRNA expression (P > 0.05). Across subjects, abundance of β-F₁ -ATPase correlated with the FSR of β-F₁ -ATPase (P < 0.05). The specific activity of muscle ATP synthase was lower in obese compared to lean subjects (0.035 ± 0.004 vs. 0.042 ± 0.007 arbitrary units; P < 0.05), but this difference was not significant after the activity of the ATP synthase was adjusted to the β-F₁ -ATPase content (P > 0.05). Obesity impairs the synthesis of β-F₁ -ATPase in muscle at the translational level, reducing the content of β-F₁ -ATPase in parallel with reduced capacity for ATP generation via the ATP synthase complex.

Physical activity is related to function and fatigue but not pain in women with fibromyalgia: baseline analyses from the Fibromyalgia Activity Study with TENS (FAST)

BACKGROUND

Although exercise is an effective treatment for fibromyalgia, the relationships between lifestyle physical activity and multiple symptomology domains of fibromyalgia are not clear. Thus, the purpose of this study was to comprehensively examine the relationships between lifestyle physical activity with multiple outcome domains in women with fibromyalgia, including pain, fatigue, function, pain-related psychological constructs, and quality of life.

METHODS

Women (N = 171), aged 20 to 70 years, diagnosed with fibromyalgia, recruited from an ongoing two-site clinical trial were included in this prespecified subgroup analysis of baseline data. Physical activity was assessed using self-report and accelerometry. Symptomology was assessed using questionnaires of perceived physical function, quality of life, fatigue, pain intensity and interference, disease impact, pain catastrophizing, and fear of movement. In addition, quantitative sensory testing of pain sensitivity and performance-based physical function were assessed. Correlation coefficients, regression analyses and between-group differences in symptomology by activity level were assessed, controlling for age and body mass index (BMI).

RESULTS

Lifestyle physical activity was most closely associated with select measures of physical function and fatigue, regardless of age and BMI. Those who performed the lowest levels of lifestyle physical activity had poorer functional outcomes and greater fatigue than those with higher physical activity participation. No relationships between lifestyle physical activity and pain, pain sensitivity, or pain-related psychological constructs were observed.

CONCLUSIONS

Lifestyle physical activity is not equally related to all aspects of fibromyalgia symptomology. Lifestyle physical activity levels have the strongest correlations with function, physical quality of life, and movement fatigue in women with fibromyalgia. No relationships between lifestyle physical activity and pain, pain sensitivity, or psychological constructs were observed. These data suggest that physical activity levels are more likely to affect function and fatigue, but have negligible relationships with pain and pain-related psychological constructs, in women with fibromyalgia.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT01888640 . Registered on 28 June 2013.

The role of trehalose in the global spread of epidemic Clostridium difficile

In a recent study, we reported on two distantly related, epidemic lineages of Clostridium difficile that have acquired independent mechanisms to metabolize low concentrations of trehalose. Here we provide further comment and evidence that a third epidemic lineage common in Asia and Europe, ribotype 017, has evolved this ability.

The influence of high-intensity interval training and moderate-intensity continuous training on sedentary time in overweight and obese adults

High-intensity interval training (HIIT) elicits health benefits but it is unclear how HIIT impacts sedentary behaviour. In this preliminary study, we compared the effects of supervised HIIT or moderate-intensity continuous training (MICT) on sedentary time in overweight/obese adults. In both groups, percentage of time spent in sedentary activities was significantly reduced during the supervised exercise intervention (time main effect, P = 0.03), suggesting that both HIIT and MICT replaced time spent previously being sedentary.

Plasma Amino Acids Stimulate Uncoupled Respiration of Muscle Subsarcolemmal Mitochondria in Lean but Not Obese Humans

CONTEXT

Obesity is associated with mitochondrial dysfunction in skeletal muscle. Increasing the plasma amino acid (AA) concentrations stimulates mitochondrial adenosine triphosphate (ATP) production in lean individuals.

OBJECTIVE

To determine whether acute elevation in plasma AAs enhances muscle mitochondrial respiration and ATP production in subsarcolemmal (SS) and intermyofibrillar (IMF) mitochondria in obese adults.

DESIGN

Assessment of SS and IMF mitochondrial function during saline (i.e., control) and AA infusions.

PARTICIPANTS

Eligible participants were healthy lean (body mass index, <25 kg/m2; age, 37 ± 3 years; n = 10) and obese (body mass index >30 kg/m2; age 35 ± 3 years; n = 11) subjects.

INTERVENTION

Single trial of saline infusion followed by AA infusion. SS and IMF mitochondria were isolated from muscle biopsies collected at the end of the saline and AA infusions.

MAIN OUTCOMES

Mitochondrial respiration and ATP production.

RESULTS

AA infusion increased adenosine 5'-diphosphate (ADP)-stimulated respiration and ATP production rates of SS mitochondria in the lean (P < 0.05), but not obese, subjects. Furthermore, AA infusion increased the uncoupled (i.e., non-ADP-stimulated) respiration of SS mitochondria in the lean subjects only (P < 0.05). AA infusion had no effect on any of these parameters in IMF mitochondria in either lean or obese subjects (P > 0.05).

CONCLUSIONS

Increasing the plasma AA concentrations enhances the capacity for respiration and ATP production of muscle SS, but not IMF, mitochondria in lean individuals, in parallel with increases in uncoupled respiration. However, neither of these parameters increases in muscle SS or IMF mitochondria in obese individuals.

Relationships between physical activity, food choices, gender and BMI in Southern Californian teenagers

Given the increased prevalence of pediatric obesity and risk of developing chronic disease, there has been great interest in preventing these conditions during childhood by focusing on healthy lifestyle habits, including nutritious eating and physical activity (PA). The purpose of this study was to determine the relationship between PA, body mass index (BMI) and food choices in adolescent males and females. This cross-sectional study, using a survey questionnaire, evaluated 1212 Southern Californian adolescents' self-reported PA, BMI and food frequency. Results revealed that even though males are more active than females, they have higher BMI percentile values (p < 0.05). Females consumed salad, vegetables and fruit more frequently than males (p < 0.05), where males consumed hamburgers, pizza, red meat, processed meat, eggs, fish, fruit juice, soda and whole milk more frequently than females (p < 0.05). Overweight/obese teens consumed red meat, processed meat and cheese more frequently than healthy weight teens (p < 0.05), yet there was no difference in PA between healthy and overweight/obese teens. These results demonstrate that higher levels of PA may not counteract an unhealthy diet. Even though PA provides numerous metabolic and health benefits, this study suggests that healthy food choices may have a protective effect against overweight and obesity. Healthy food choices, along with PA, should be advocated to improve adolescent health by encouraging maintenance of a healthy weight into adulthood.

Obesity History and Daily Patterns of Physical Activity at Age 60-64 Years: Findings From the MRC National Survey of Health and Development

Background

The aim of this study was to investigate associations of current body mass index (BMI) and obesity history with daily patterns of physical activity.

Methods

At age 60-64, participants from a British birth cohort study wore accelerometers for 5 days. Accelerometry counts were log-transformed and mean log-counts were used to derive a summary variable indicating total daily log-activity counts. Among those with complete data (n = 1,388) the associations of current BMI and age of first obesity were examined with: (a) total daily log-activity counts and (b) total log-activity counts in four segments of the day.

Results

Higher current BMI and younger age at obesity were strongly associated with lower levels of total daily activity at age 60-64 even after adjustment for sex, socioeconomic factors, and health status. The fully-adjusted mean difference in total daily log-activity counts was -581.7 (95% confidence interval: -757.2, -406.3) when comparing BMI ≥35 kg/m2 with <25 kg/m2, representing an 18.4% difference. Participants who had been obese since early adulthood had the lowest levels of activity (mean difference in total daily log-activity counts was -413.1 (-638.1, -188.2) when comparing those who were obese by age 26 or 36 with those who were never obese, representing a 13.1% difference).

Conclusions

Obese older adults may require targeted interventions and additional support to improve their daily activity levels. As younger generations with greater lifetime exposure to obesity reach old age the proportion of adults achieving sufficient levels of activity to realize its associated health benefits is likely to decline.

Obesity is associated with poorer range of motion and Tegner scores following hamstring autograft anterior cruciate ligament reconstruction in Asians

BACKGROUND

Current literature reporting on the impact of BMI on outcomes of orthopaedic surgical procedures is varied and inconsistent. The purpose of our study was to evaluate if body mass index (BMI) affects outcomes of primary anterior cruciate ligament reconstruction (ACLR) in an Asian population.

METHODS

We retrospectively reviewed prospectively collected data of 141 consecutive patients who underwent primary ACLR by a single surgeon, the senior author of this study. Flexion range, International Knee Documentation Committee (IKDC) score, KT-1000 translation, Tegner activity level scale, Lysholm score and satisfaction were assessed preoperatively and at 2 years postoperatively. The patients were then stratified into two groups: normal-BMI and high-BMI in accordance with WHO classification. Outcomes were then compared between the two groups. All statistical analysis were performed on IBM SPSS Statistics 20.

RESULTS

There were 81 patients in the normal-BMI group (BMI, 18.5 to 24.9) and 60 patients in the high-BMI group (BMI ≥25). Preoperatively, the only differences were in the gender proportions as well as the pre-injury Tegner score. 2-years postoperatively, patients in the normal-BMI group had better flexion (139° vs. 130°; P=0.0001), Tegner scores (5.7 vs. 4.8; P=0.005) and satisfaction rate (99% vs. 90%; P=0.041). There were no differences in graft failure or complication rates.

CONCLUSIONS

Obese patients had poorer range of motion and Tegner scores as compared to their nonobese counterparts following primary ACLR.

Health enhancing physical activity in patients with hip or knee osteoarthritis - an observational intervention study

Background

Osteoarthritis is one of the leading causes of inactivity worldwide. The recommended level of health enhancing physical activity (HEPA) is at least 150 min of moderate intensity physical activity per week. The purpose of this study was to explore how the proportion of patients, who reached the recommended level of HEPA, changed following a supported osteoarthritis self-management programme in primary care, and to explore how reaching the level of HEPA was influenced by body mass index (BMI), gender, age and comorbidity.

Methods

An observational study was conducted using data from a National Quality Registry in which 6810 patients in primary care with clinically verified hip or knee osteoarthritis with complete data at baseline, 3 and 12 months follow-up before December 31^st 2013 were included. HEPA was defined as self-reported physical activity of at least moderate intensity either a) at least 30 min per day on four days or more per week, or b) at least 150 min per week. HEPA was assessed at baseline, and again at 3 and 12 months follow-up. Cochran’s Q test was used to determine change in physical activity over time. The association between reaching the level of HEPA and time, age, BMI, gender, and Charnley classification was investigated using the generalized estimation equation (GEE) model.

Results

The proportion of patients who reached the level of HEPA increased by 345 patients, from 77 to 82%, from baseline to 3 months follow-up. At 12 months, the proportion of patients who reached the level of HEPA decreased to 76%. Not reaching the level of HEPA was associated with overweight, obesity, male gender and Charnley category C, i.e. osteoarthritis in multiple joint sites (hip and knee), or presence of any other disease that affects walking ability.

Conclusions

Following the supported osteoarthritis self-management programme there was a significant increase in the proportion of patients who reached the recommended level of HEPA after 3 months. Improvements were lost after 12 months. To increase physical activity and reach long-lasting changes in levels of physical activity, more follow-up sessions might be needed.

Physical activity levels in adults with congenital heart disease

BACKGROUND

Regular physical activity is associated with many health benefits in patients with cardiac disease. Advances in treatment have resulted in an increasing population of adults with congenital heart disease. Few data are available on physical activity levels and attitude to exercise in this group.

DESIGN

Prospective, cross-sectional study of patients attending the adult congenital heart disease clinic in a supra-regional centre.

METHODS

Physical activity assessed over 1 week using two accelerometers. The Actigraph was used to measure total activity volume and intensity and the Caltrac used to measure energy expenditure in physical activity. Patients completed a questionnaire to assess exercise self-efficacy.

RESULTS

In all, 61 adults recruited (36 male; mean-age 31.7+/-10.9 years); divided into three groups according to New York Heart Association class [Group I (n=26; 14 male), Group II (n=18; 10 male), Group III (n=17; 11 male)]. Fourteen patients were overweight (body mass index 25-29.9) and seven obese (body mass index>30). Group 1 achieved similar activity levels to a sedentary reference population. Group II and III had significantly lower activity (55 and 40% of Group I). Most study patients failed to achieve UK national guidelines for physical activity (Groups I: 77%, II: 84%, III: 100%). Despite this, questionnaire responses suggested a willingness to participate in exercise in the majority of each group.

CONCLUSIONS

Adults with congenital heart disease have a range of physical activity levels between normal and severely limited. Most patients showed a willingness to participate in exercise but were uncertain of the safety or benefit. Intervention to increase physical activity levels may be a low risk, low cost treatment strategy.

Wearable inertial sensors for human movement analysis

INTRODUCTION

The present review aims to provide an overview of the most common uses of wearable inertial sensors in the field of clinical human movement analysis.

AREAS COVERED

Six main areas of application are analysed: gait analysis, stabilometry, instrumented clinical tests, upper body mobility assessment, daily-life activity monitoring and tremor assessment. Each area is analyzed both from a methodological and applicative point of view. The focus on the methodological approaches is meant to provide an idea of the computational complexity behind a variable/parameter/index of interest so that the reader is aware of the reliability of the approach. The focus on the application is meant to provide a practical guide for advising clinicians on how inertial sensors can help them in their clinical practice. Expert commentary: Less expensive and more easy to use than other systems used in human movement analysis, wearable sensors have evolved to the point that they can be considered ready for being part of routine clinical routine.

Is There an Association Between the Body Mass Index and Interpersonal Violent Behavior?

An inverse relationship between the body mass index (BMI) and the risk of completed suicide was shown in several studies. Furthermore, it is suggested that obesity might be associated with a lower risk for violent criminality. Therefore, the aim of this study was to analyze whether a higher BMI is associated with a lower risk for being arrested due to violent behavior in a sample of 43,992 male offenders. Multinomial logistic regression analysis was applied to assess the relationship between different BMI categories and categories of committed crime as outcome variable by including various covariates. Our results indicated that compared to a normal BMI a higher BMI was associated with a significantly lower risk for being arrested in different crime categories associated with interpersonal violence, such as crimes against life and limb (for example: odds ratio=0.60, CI 95%: 0.52-0.69 for 30-34.9 kg/m2).

Physical inactivity and incidence of obesity among South Australian adults

The aim of this paper is to examine the association of physical inactivity with incidence of obesity in the South Australian adult population. Two representative data sources were used - the South Australian Monitoring and Surveillance System (SAMSS), a monthly surveillance system, and the North West Adelaide Health Study (NWAHS), a biomedical cohort study. There were 75.3% (n = 12873) SAMSS participants and 72.8% (n = 1521) of NWAHS participants that were not obese at baseline. The cumulative incidence of obesity for SAMSS participants from the previous year to the current year was 2.7%. The cumulative incidence of obesity for NWAHS participants between baseline and stage 3 was 14.4%. Physical inactivity was associated with incident obesity (RR 1.48, 95% CI 1.14-1.90 [SAMSS] and RR 1.41, 95% CI 1.03-1.93 [NWAHS]). This association remained, but was attenuated after adjustment for chronic conditions, risk factors and socio-demographic factors. However, physical activity should be continued to be encouraged in the population for its known additional health benefits.

Body mass index is associated with appropriateness of weight gain but not leisure-time physical activity during pregnancy

BACKGROUND

Little is known about how leisure-time physical activity (LTPA) influences gestational weight gain (GWG) among body mass index (BMI) categories. The purpose of this study was to examine the relationship between pregnancy LTPA and the proportion of normal, overweight, and obese women who meet GWG recommendations.

METHODS

Participants included 449 subcohort women from the Pregnancy Outcomes and Community Health (POUCH) study. LTPA was collapsed into 3 categories [(None, < 7.5 kcal/kg/wk (low), ≥ 7.5 kcal/kg/wk (recommended)]. GWG was categorized according to IOM recommendations (low, recommended, or excess). Chi-square and logistic regression analyses were used to evaluate relationships among LTPA, BMI, and GWG.

RESULTS

Overweight women were more likely to have high GWG vs. normal weight women (OR = 2.3, 95% CI 1.3-4.0). Obese women were more likely to experience low GWG (OR = 7.3, 95% CI 3.6-15.1; vs. normal and overweight women) or excess GWG (OR = 3.5, 95% CI 1.9-6.5; vs. normal weight women). LTPA did not vary by prepregnancy BMI category (P = .55) and was not related to GWG in any prepregnancy BMI category (P = .78).

CONCLUSIONS

Regardless of prepregnancy BMI, LTPA did not affect a woman's GWG according to IOM recommendations. Results may be due to LTPA not differing among BMI categories.

Associations among gestational weight gain, physical activity, and pre-pregnancy body size with varying estimates of pre-pregnancy weight

OBJECTIVES

the purpose of this study was to examine associations among gestational weight gain (GWG) and pregnancy leisure-time physical activity (LTPA), within pre-pregnancy body mass index (BMI) categories, while utilising two different estimates of pre-pregnancy weight.

DESIGN

a cohort study. Data were collected via questionnaire and abstraction from birth certificate as a part of a larger study.

SETTING

three antenatal clinics in Lansing, Michigan, USA.

PARTICIPANTS

a subset of women who participated in the Archive for Research on Child Health (ARCH) study and delivered a singleton, term infant (n=135). Participants were enroled prior to 14 weeks׳ gestation.

MEASUREMENTS

pre-pregnancy BMI was categorised as normal, overweight and obese (excluded underweight). GWG was calculated by subtracting pre-pregnancy weight from weight at childbirth (obtained from birth certificate) and classified as 'excess' or 'not excess' using the upper limit of the 2009 IOM recommended range. These two variables were constructed twice, first by using pre-pregnancy weight self-reported at enrolment and second, by using pre-pregnancy weight recorded on birth certificates. LTPA, also self-reported at enrolment, was modelled using two thresholds, moderate LTPA, and vigorous LPTA.

FINDINGS

overall, 56-60% of our sample experienced excess GWG, depending on the source used for pre-pregnancy weight. Overweight and obese women had significantly higher odds of excess GWG (compared to normal weight women; Odds Ratio (OR)=2.48-5.34). LTPA level did not differ among pre-pregnancy BMI categories and was not related to appropriateness of GWG.

KEY CONCLUSIONS

regardless of the source of pre-pregnancy weight, overweight and obese women were more likely to experience excess GWG (compared to normal weight women) and LTPA was not significantly related to the appropriateness of GWG.

IMPLICATIONS FOR PRACTICE

findings highlight the need for practitioners to effectively communicate GWG recommendations and counsel women about the importance of achieving appropriate GWG. Although GWG counselling has traditionally been focused on obese women, these results suggest overweight women are in need of GWG counselling as well.

Adherence to accelerometry measurement of community ambulation poststroke

BACKGROUND

The step activity monitor (SAM) quantifies steps taken in the home and community by patient populations. Although the SAM has been used to study individuals after stroke, adherence to the use of SAMs has not been addressed. Participants' adherence to wearing the monitor is critical for obtaining accurate assessments.

OBJECTIVE

The purpose of this study was to determine the rate of and predictors for inferred adherence to the use of the SAM after stroke.

DESIGN

A cross-sectional design was used.

METHODS

Community-dwelling individuals (n=408) 2 months after stroke with moderate-to-severe gait impairment (gait speed of ≤0.8 m/s) were studied. Step activity was assessed for 2 days with the SAM. Inferred adherence was established in 3 periods: 6:00 am to 12:00 pm, 12:01 pm to 6:00 pm, and 6:01 pm to 12:00 am. Adherence was defined as activity recorded in all 3 periods. The percentage of participant adherence for the first day, second day, both days, and either day was calculated. Demographic and clinical characteristics of adherers and nonadherers were compared. Independent adherence predictors were identified by means of stepwise logistic regression.

RESULTS

Inferred adherence rates for the first day, second day, both days, and either day were 68%, 61%, 53%, and 76%, respectively. Upper and lower extremity impairment, balance control, and endurance were significantly different between adherers and nonadherers. On the other hand, older age, greater balance self-efficacy, and better walking endurance were significant predictors of adherence.

LIMITATIONS

Participants were individuals with subacute stroke. Therefore, the findings of this study may not be generalized to individuals during the acute and chronic phases of stroke recovery.

CONCLUSIONS

Strategies to improve adherence are needed when collecting data for more than 1 day and in samples with younger individuals and those with low levels of balance self-efficacy and walking endurance.

Neighborhood walkability, income, and hour-by-hour physical activity patterns

PURPOSE

This study aimed to investigate both the mean daily physical activity and the hour-by-hour physical activity patterns across the day using accelerometry and how they are associated with neighborhood walkability and individual income.

METHODS

Moderate physical activity (MPA) was assessed by accelerometry in 2252 adults in the city of Stockholm, Sweden. Neighborhood walkability (residential density, street connectivity, and land use mix) was objectively assessed within 1000m network buffers around the participants' residence and individual income was self-reported.

RESULTS

Living in a high walkability neighborhood was associated with more mean daily MPA compared with living in a low walkability neighborhood on weekdays and weekend days. Hour-by-hour analyses showed that this association appeared mainly in the afternoon/early evening during weekdays, whereas it appeared across the middle of the day during weekend days. Individual income was associated with mean daily MPA on weekend days. On weekdays, the hour-by-hour analyses showed that high income was associated with more MPA around noon and in late afternoon/early evening, whereas low income was associated with more MPA at the hours before noon and in the early afternoon. During the weekend, high income was more consistently associated with higher MPA.

CONCLUSIONS

Hour-by-hour accelerometry physical activity patterns provides a more comprehensive picture of the associations between neighborhood walkability and individual income and physical activity and the variability of these associations across the day.

Objectively measured sedentary time and physical activity in women with fibromyalgia: a cross-sectional study

OBJECTIVES

To characterise levels of objectively measured sedentary time and physical activity in women with fibromyalgia.

DESIGN

Cross-sectional study.

SETTING

Local Association of Fibromyalgia (Granada, Spain).

PARTICIPANTS

The study comprised 94 women with diagnosed fibromyalgia who did not have other severe somatic or psychiatric disorders, or other diseases that prevent physical loading, able to ambulate and to communicate and capable and willing to provide informed consent.

PRIMARY OUTCOME MEASURES

Sedentary time and physical activity were measured by accelerometry and expressed as time spent in sedentary behaviours, average physical activity intensity (counts/minute) and amount of time (minutes/day) spent in moderate intensity and in moderate-to-vigorous-intensity physical activity (MVPA).

RESULTS

The proportion of women meeting the physical activity recommendations of 30 min/day of MVPA on 5 or more days a week was 60.6%. Women spent, on average, 71% of their waking time (approximately 10 h/day) in sedentary behaviours. Both sedentary behaviour and physical activity levels were similar across age groups, waist circumference and percentage body fat categories, years since clinical diagnosis, marital status, educational level and occupational status, regardless of the severity of the disease (all p>0.1). Time spent on moderate-intensity physical activity and MVPA was, however, lower in those with greater body mass index (BMI) (-6.6 min and -7 min, respectively, per BMI category increase, <25, 25-30, >30 kg/m(2); p values for trend were 0.056 and 0.051, respectively). Women spent, on average, 10 min less on MVPA (p<0.001) and 22 min less on sedentary behaviours during weekends compared with weekdays (p=0.051).

CONCLUSIONS

These data provide an objective measure of the amount of time spent on sedentary activities and on physical activity in women with fibromyalgia.

Patterns of objectively measured physical activity in normal weight, overweight, and obese individuals (20-85 years): a cross-sectional study

BACKGROUND

The magnitude of the association between physical activity (PA) and obesity has been difficult to establish using questionnaires. The aim of the study was to evaluate patterns of PA across BMI-defined weight categories and to examine the independent contribution of PA on weight status, using accelerometers.

METHODS

The study was a cross-sectional population-based study of 3,867 adults and older people aged 20-85 years, living in Norway. PA was assessed for seven consecutive days using the ActiGraph GT1M accelerometer. Anthropometrical data was self-reported and overweight and obesity was defined as having a body mass index (BMI) of 25-<30 and ≥30 kg/m(2), respectively.

RESULTS

Overweight and obese participants performed less overall PA and PA of at least moderate intensity and took fewer steps, compared to normal weight participants. Although overall PA did not differ between weekdays and weekends, an interaction between BMI category and type of day was present, indicating a larger difference in overall PA between BMI categories on weekends compared to weekdays. Obese participants displayed 19% and 25% lower overall physical activity compared to normal weight participants, on weekdays and weekends, respectively. Participants in the most active quintile of overall PA had a 53% lower risk (OR 0.47, 95% CI: 0.37 to 0.60) for having a BMI above or below 25 kg/m(2), and a 71% lower risk (OR: 0.29, 95% CI: 0.20 to 0.44) for having a BMI above or below 30 kg/m(2).

CONCLUSIONS

Overweight and obese participants engaged in less overall PA and moderate and vigorous PA compared with normal weight individuals. The weight related differences in overall PA were most pronounced on the weekend and the risk of being overweight or obese decreases across quintiles of PA.