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Background/Objectives: Accurate assessments of energy intake (EI) are needed in lifestyle interventions to guarantee a negative energy balance (EB), thereby losing weight. This study aimed (1) to compare objectively measured and self-reported EI and (2) to determine the predictors of underreporting divided by sex, adiposity and BMI category. Methods: Seventy-three participants [mean (SD): 43.7 (9.2) years, BMI = 31.5 (4.5) kg/m2, 37% females] of the Champ4Life intervention were included in this study. EI was measured using the “intake-balance method” and self-reported through 3-day food records. Fat mass (FM) and fat-free mass (FFM) were measured by dual-energy X-ray absorptiometry. Bland–Altman analysis was performed to compare both EI assessments. Results: Self-reported EI was lower than measured EI during both neutral (–355 kcal/d) and negative EB (–570 kal/day). While no significant trends were observed for EI evaluation in either neutral (p= 0.315) or negative EB (p= 0.611), limits of agreement were wide (–1720 to 1010 and –1920 to 779 kcal/day, respectively). In females, the degree of misreporting (kcal/day and %) was predicted by weight (p= 0.032 and p= 0.039, respectively) and FM (p= 0.029 and p= 0.037, respectively). In males, only BMI (p= 0.036) was a predictor of misreporting (kcal/day). Conclusion: Self-reported EI did not agree with measured EI. Our results show that larger body size was associated with higher levels of underestimation for EI (females only). Nevertheless, misreporting EI is a complex issue involving more associations than merely body composition. A deeper understanding could inform counseling for participants filling out food records in other to reduce misreporting and improve validity.

Graphical Abstract:

Background/objectives: Physical activity (PA) guidelines advocate that children should accumulate at least 60 min of moderate-to-vigorous PA daily. Still, it is not clear how body fat may differ if the same dose of PA is accumulated at different intensities. We aimed to determine the independent associations of energy expenditure (EE) at moderate (MPA) and vigorous (VPA) PA intensity on total and abdominal fat in children and if these associations were moderated by cardiorespiratory fitness (CRF). Subjects/methods: A total of 326 children (girls = 171, boys = 151) aged 10–12 years had PA assessed with accelerometers. Total fat mass index (FMI) and abdominal FMI were assessed with DXA. CRF was assessed by a cycle ergometer test. Linear regression models were used to model the outcomes with the inclusion of an interaction term to test for moderation effects. Results: An inverse association was found between VPA EE and FMI (β= −0.013, p< 0.001) and abdominal FMI (β= −0.0014, p< 0.001) independent of MPA EE. In contrast, MPA EE was not related to adiposity independent of VPA EE (p> 0.05). The relationships between the PA intensities and FMI and abdominal FMI were moderated by CRF. MPA EE was positively associated with adiposity in children with high levels of CRF, whereas VPA EE remained inversely associated with adiposity regardless of CRF level, although the strength of the association was lower in those with higher CRF levels. Conclusion: PA programs should provide opportunities for children to perform VPA in order to achieve healthier body fat profiles and avoid excess adiposity.

Background: Bioelectrical impedance analysis (BIA) is a technique widely used for estimating body composition and health-related parameters. The technology is relatively simple, quick, and non-invasive, and is currently used globally in diverse settings, including private clinicians’ offices, sports and health clubs, and hospitals, and across a spectrum of age, body weight, and disease states. BIA parameters can be used to estimate body composition (fat, fat-free mass, total-body water and its compartments). Moreover, raw measurements including resistance, reactance, phase angle, and impedance vector length can also be used to track health-related markers, including hydration and malnutrition, and disease-prognostic, athletic and general health status. Body composition shows profound variability in association with age, sex, race and ethnicity, geographic ancestry, lifestyle, and health status. To advance understanding of this variability, we propose to develop a large and diverse multi-country dataset of BIA raw measures and derived body components. The aim of this paper is to describe the ‘BIA International Database’ project and encourage researchers to join the consortium. Methods: The Exercise and Health Laboratory of the Faculty of Human Kinetics, University of Lisbon has agreed to host the database using an online portal. At present, the database contains 277,922 measures from individuals ranging from 11 months to 102 years, along with additional data on these participants. Conclusion: The BIA International Database represents a key resource for research on body composition.

Cunha, PM, Ribeiro, AS, Padilha, C, Nunes, JP, Schoenfeld, BJ, Cyrino, LT, Tomeleri, CM, Nascimento, MA, Antunes, M, Fernandes, RR, Barbosa, DS, Venturini, D, Burini, RC, Sardinha, LB, and Cyrino, ES. Improvement of oxidative stress in older women is dependent on resistance training volume: Active aging longitudinal study. J Strength Cond Res36(4): 1141–1146, 2022—The purpose of the present study was to investigate the effects of resistance training (RT) performed with a higher versus lower training volume on oxidative stress (OS) biomarkers in older women. Thirty-eight older women (≥60 years) were randomly assigned to 1 of 2 groups: a group that performed 1 set per exercise (low volume [LV], n= 18) or 3 sets per exercise (high volume [HV], n= 20). The whole-body RT consisted of a 12-week RT program involving 8 exercises performed with sets of 10–15 repetitions maximum, 3 days per week. Advanced oxidation protein products (AOPP), total radical-trapping antioxidant parameter (TRAP), and ferrous oxidation-xylenol orange (FOX) were used as OS biomarkers. The composite Z-score of the percentage changes from pre- to posttraining of OS biomarkers according to groups was calculated. A significant main effect of time (p< 0.05) was found for AOPP (LV = −7.3% vs. HV = −12.2%) and TRAP (LV = +1.5% vs. HV = +15.5%) concentrations, without a statistical difference between the groups (p> 0.05). A significant group vs. time interaction (p< 0.001) was revealed for FOX (LV = +6.4% vs. HV = −8.9%). The overall analysis indicated higher positive changes for HV than LV (composed Z-score: HV = 0.41 ± 1.22 vs. LV = −0.37 ± 1.03; p< 0.05). Our results suggest that a greater volume of RT seems to promote superior improvements on OS biomarkers in older women.

Background/Objectives: Bioelectrical impedance (BIA) whole-body and regional raw parameters have been used to develop prediction models to estimate whole-body lean soft tissue (LSTM), with less attention being given to the development of models for regional LSTM. Therefore, we aimed to develop and validate BIA-derived equations predicting regional LSTM against dual x-ray absorptiometry (DXA) in healthy adults. Subjects/Methods: 149 adults were included in this cross-sectional investigation. Whole-body and regional LSTM were assessed by DXA, and raw bioelectrical parameters of distinct body regions were measured using a 50 kHz phase sensitive BIA analyzer. BIA-derived equations were developed using a stepwise multiple linear regression approach in 2/3 of the sample and cross-validated in the remaining sample. Results: Slopes and intercepts of predicted LSTM and DXA measured LSTM did not differ from 1 and 0, respectively, for each region (p≥ 0.05), with the exception for the trunk (p&lt; 0.05). The BIA-derived equations exhibited a strong relationship (p&lt; 0.001) between the predicted and measured LSTM for each of the following body regions: right and left arms (R = 0.94; R = 0.96), right and left legs (R = 0.88; R = 0.88), upper body (R = 0.96), lower body (R = 0.89), right and left sides of the body (R = 0.94; R = 0.94), and trunk (R = 0.90). Agreement analyses revealed no associations between the differences and the means of the predicted and DXA-derived LSTM. Conclusion: The developed BIA-derived equations provide a valid estimate of regional LSTM in middle-aged healthy adults, representing a cost-effective and time-efficient alternative to DXA for the assessment and identification of LSTM imbalances in both clinical and sport-specific contexts.

Background: Many factors may influence the magnitude of individual responses to resistance training (RT). How the manipulation of training volume and frequency affects responsiveness level for muscle mass gain in older women has not been investigated. Aims: This study had the objective of identifying responders (RP) and non-responders (N-RP) older women for skeletal muscle mass (SMM) gain from a 12-week resistance training (RT) program. Additionally, we analyzed whether the N-RP could gain SMM with an increase in weekly training volume over 12 additional weeks of training. Methods: Thirty-nine older women (aged ≥ 60 years) completed 24 weeks of a whole-body RT intervention (eight exercises, 2–3×/week, 1–2 sets of 10–15 repetitions). SMM was estimated by DXA, and the responsive cut-off value was set at two times the standard error of measurement. Participants were considered as RP if they exceeded the cut-off value after a 12-week RT phase, while the N-RP were those who failed to reach the SMM cut-off. Results: Of the 22 participants considered to be N-RP, only 3 accumulated SMM gains (P= 0.250) that exceeded the cut-off point for responsiveness following 12 additional weeks of training, while 19 maintained or presented negative SMM changes. Of the 17 participants considered to be RP, all continued to gain SMM after the second 12-week RT phase. No significant correlation was observed between the changes in SMM and any baseline aspect of the participants. Conclusions: Our results suggest that some older women are RP, while others are N-RP to SMM gains resulting from RT. Furthermore, the non-responsiveness condition was not altered by an increase of training volume and intervention duration while RP participants continue to increase SMM; it appears that RP continue to be RP, and N-RP continue to be N-RP.

Assessing vital signs such as heart rate (HR) by wearable devices in a lifestyle-related environment provides widespread opportunities for public health related research and applications. Commonly, consumer wearable devices assessing HR are based on photoplethysmography (PPG), where HR is determined by absorption and reflection of emitted light by the blood. However, methodological differences and shortcomings in the validation process hamper the comparability of the validity of various wearable devices assessing HR. Towards Intelligent Health and Well-Being: Network of Physical Activity Assessment (INTERLIVE) is a joint European initiative of six universities and one industrial partner. The consortium was founded in 2019 and strives towards developing best-practice recommendations for evaluating the validity of consumer wearables and smartphones. This expert statement presents a best-practice validation protocol for consumer wearables assessing HR by PPG. The recommendations were developed through the following multi-stage process: (1) a systematic literature review based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses, (2) an unstructured review of the wider literature pertaining to factors that may introduce bias during the validation of these devices and (3) evidence-informed expert opinions of the INTERLIVE Network. A total of 44 articles were deemed eligible and retrieved through our systematic literature review. Based on these studies, a wider literature review and our evidence-informed expert opinions, we propose a validation framework with standardised recommendations using six domains: considerations for the target population, criterion measure, index measure, testing conditions, data processing and the statistical analysis. As such, this paper presents recommendations to standardise the validity testing and reporting of PPG-based HR wearables used by consumers. Moreover, checklists are provided to guide the validation protocol development and reporting. This will ensure that manufacturers, consumers, healthcare providers and researchers use wearables safely and to its full potential.

•Evidence of correlates for physical activity rely mostly on subjective metrics.•We included sensor-based physical activity, sedentary time, and self-reported cell phone time.•A multiplicity of correlates were hierarchized using Chi-squared Automatic Interaction Detection analysis in 2179 youths.•Girls, sport participation/facilities, neighborhood, and family must be prioritized.

Background/objectives: The ability to adapt the level of daily fuel utilization to substrate availability is given by the respiratory quotient (RQ), which its variance is an indicator of metabolic flexibility. Metabolic inflexibility is associated with many pathologies including obesity, but evidence relies on bed-rest studies and exercise-based interventions. Our goal was to examine the associations for RQ variance in response to daily living activities with obesity, in healthy adults. Subjects/methods: Participants (N?=?50; 25 women), 20–64 years were lying for 60?min and randomly performed three conditions for 10?min each (sitting, standing, 1 sit/stand/sit transition?min-1). RQ was measured by indirect calorimetry and fat mass (FM), trunk FM (TFM), and fat-free mass (FFM) by DXA. Results: RQ variance among the three conditions was inversely associated with BMI (ß?=?0.005; p?&lt;?0.001), FM (ß?=?0.007; p?=?0.024), and TFM (ß?=?0.008; p?=?0.026). A positive association was found between RQ variance and FFM (ß?=?-0.007; p?=?0.024). No interactions for sex were found (p?=?0.05). Conclusions: These findings suggest that a higher RQ variance in response to daily living metabolic challenges such as transitioning between sitting and standing is associated with lower overall and central obesity, as well as with a higher FFM, in healthy adults. Thus, RQ variance may work as an indication of metabolic flexibility, but these findings were obtained in a young and non-obese adult population without considering their fitness levels. Thus, further research in this field is warranted.

Background/objective: Knowing the distribution of lean soft tissue (LST) among the body segments is of relevance for optimizing athletic performance, monitoring response to training, and for evaluating injury risk. Bioelectrical impedance (BIA) is a portable, low cost, and easy technique to assess body composition. However, most equations used by BIA to predict LST are not specific for the athlete population. The aim of this investigation was to develop and validate equations to estimate dual-energy X-ray absorptiometry (DXA) appendicular LST of the arms and legs based on whole-body BIA in athletes. Methods: Arms and legs LST were assessed by DXA and whole-body reactance (Xc) and resistance (R) were measured by BIA in athletes from various sports. Using measures of height, the resistance index (RI) (RI?=?height2/R) was calculated. Prediction equations were established using a cross-validation method where 177 athletes (2/3 of sample) were used for equation development and the remaining 88 athletes (1/3 of sample) were used for equation validation. Results: The developed prediction equations were as follows: arm LST?=?0.940?×?sex (0?=?male; 1?=?female)?+?0.042?×?total body weight (kg)?+?0.080?×?RI?+?0.024?×?Xc?-?3.927; leg LST?=?1.983?×?sex (0?=?male; 1?=?female)?+?0.154?×?total body weight (kg)?+?0.127?×?RI?-?1.147. Both equations validated well for the arms (mean difference?=?0.11?kg, R2?=?0.89, pure error (PE)?=?0.61) and for the legs (mean difference?=?0.05?kg, R2?=?0.81, PE?=?1.93?kg). There were no differences (p?>?0.05) in the mean observed and predicted LST for the arms and legs. Conclusion: The developed BIA-based prediction equations provide a valid estimation of upper and lower body LST in athletes.

Background: Physical activity (PA) and physical fitness (PF) are crucial for bone health. However, children participating in competitive sports with high PA are at a greater risk of fracture from trauma or overuse. Given the importance of bone development during adolescence, associations between commonly used physical fitness tests with distal third radius (R-SoS) and midshaft tibia (T-SoS) speed of sound by quantitative ultrasound were assessed in adolescent athletes and nonathletes.Hypothesis: The relationship between physical fitness tests and R-SoS and T-SoS will differ depending on sex and athletic status.Study Design: Cross-sectional study.Level of Evidence: Level 3.Methods: Physical fitness of 285 boys (156 athletes) and 311 girls (74 athletes) aged 10 to 18 years was assessed through strength, speed, agility, and cardiorespiratory tests. Linear regression was used to assess the associations of physical fitness tests with R-SoS and T-SoS.Results: For boys, favorable associations were observed between physical fitness tests with R-SoS in athletes and T-SoS in both athletes and nonathletes (P< 0.05). For nonathlete girls, favorable associations were found for handgrip (R-SoS and T-SoS, both P< 0.05), whereas the progressive aerobic cardiovascular endurance run, vertical jump, speed at 20 m and 40 m were only favorably associated with T-SoS. For athlete girls, the association between handgrip (P= 0.03), vertical jump, and 4 × 10 m shuttle run (P< 0.05) with T-SoS was significantly related to a bone outcome.Conclusion: The handgrip test and vertical jump were associated with T-SoS in boys and girls independent of sport status. These results suggest that physical fitness is associated with bone health in adolescents, particularly boys, and that the relationship between physical fitness and bone may differ depending on sex and athletic status.Clinical Relevance: Physical fitness tests are simple, easy-to-use tools for monitoring bone health and should be used by sport and health professsionals to promote healthy sport participation and prevent bone injuries.

•Based on results from previous European (Assessing Levels of PHysical Activity, ALPHA) and North American (Institute of Medicine report) projects, we have made an evidence-based proposal of core health-related fitness tests and protocols to be used worldwide.•We have gathered, through a Delphi survey, the opinions of 169 experts from major regions of the world and obtained a high response rate (78 %) and high agreement (≥85 %) for all tests and protocols.•This study therefore has achieved international consensus (initial goal, ≥80 %) on the proposed Youth Fitness International Test (YFIT) battery, which is valid, reliable, health-related, safe, feasible, and inclusive. The YFIT battery tests are: weight and height (to compute body mass index as a proxy of body size/composition), the 20-m shuttle run (cardiorespiratory fitness), handgrip strength, and standing long jump (muscular fitness).•This study contributes to standardizing fitness tests and protocols used for research, monitoring, and surveillance across the world, which will allow for future data pooling and the development of international and regional sex- and age-specific reference values, health-related cut-points, inter-country and inter-continental fitness comparisons, and ultimately provide global data that can inform surveillance and guide public health policies.

To test the biocultural model through direct and indirect associations between biological maturation, adiposity, cardiorespiratory fitness, feelings of sadness, social relationships, and physical activity in adolescents.

Background: It is important for highly active individuals to accurately assess their hydration level. Bioelectrical impedance (BIA) can potentially meet these needs but its validity in active individuals is not well established. Methods: We compared whole-body bioimpedance measurements obtained from multi-frequency bioelectrical impedance spectroscopy (BIS, Xitron 4200) at a 50?kHz frequency with those determined by a phase-sensitive single-frequency device (SF-BIA, BIA-101, RJL/Akern Systems) in two populations: active adults and elite athletes. Results: One hundred twenty-six participants, including active males involved in recreational sports (N?=?25, 20–39?yr) and elite athletes (females: N?=?26, 18–35?yr; males: N?=?75, 18–38?yr) participated in this study. Reactance (Xc), Resistance (R), Impedance (Z), and phase angle (PhA) were obtained by BIS and SF-BIA. Small but significant differences (R: -9.91?±?15.09??; Xc: -0.97?±?2.56??; Z: -9.96?±?15.18??; PhA: 0.12?±?0.2°) were observed between the bioimpedance equipment in all measured variables (p?&lt;?0.05) though differences were within the devices’ technical error of measurements. Device-specific values were highly (p?&lt;?0.0001) correlated [R2ranged from 0.881 (Xc) to 0.833 (R)], but slopes and intercepts were different (p?&lt;?0.0001) from 1 and 0, respectively. Relatively large limits of agreement were observed for R (-40 to 21??), Xc (-6 to 4??), PhA (-0.4 to 0.5°), and impedance (-40 to 20??). Conclusion:: Bioimpedance measurements from the current single- and multi-frequency devices should not be used interchangeably. The of lack of agreement between devices was observed in determining individual values of R, Xc, Z and PhA of highly active populations possibly due to methodological and biological factors.

There is considerably greater variation in metabolic rates between men than between women, in terms of basal, activity and total (daily) energy expenditure (EE). One possible explanation is that EE is associated with male sexual characteristics (which are known to vary more than other traits) such as musculature and athletic capacity. Such traits might be predicted to be most prominent during periods of adolescence and young adulthood, when sexual behaviour develops and peaks. We tested this hypothesis on a large dataset by comparing the amount of male variation and female variation in total EE, activity EE and basal EE, at different life stages, along with several morphological traits: height, fat free mass and fat mass. Total EE, and to some degree also activity EE, exhibit considerable greater male variation (GMV) in young adults, and then a decrease in the degree of GMV in progressively older individuals. Arguably, basal EE, and also morphometrics, do not exhibit this pattern. These findings suggest that single male sexual characteristics may not exhibit peak GMV in young adulthood, however total and perhaps also activity EE, associated with many morphological and physiological traits combined, do exhibit GMV most prominently during the reproductive life stages.

Sedentary time is a modifiable determinant of poor health, and in older adults, reducing sedentary time may be an important first step in adopting and maintaining a more active lifestyle. The primary purpose of this consensus statement is to provide an integrated perspective on current knowledge and expert opinion pertaining to sedentary behaviour in older adults on the topics of measurement, associations with health outcomes, and interventions. A secondary yet equally important purpose is to suggest priorities for future research and knowledge translation based on gaps identified. A five-step Delphi consensus process was used. Experts in the area of sedentary behaviour and older adults (n=15) participated in three surveys, an in-person consensus meeting, and a validation process. The surveys specifically probed measurement, health outcomes, interventions, and research priorities. The meeting was informed by a literature review and conference symposium, and it was used to create statements on each of the areas addressed in this document. Knowledge users (n=3) also participated in the consensus meeting. Statements were then sent to the experts for validation. It was agreed that self-reporttools need to be developed for understanding the context in which sedentary time is accumulated. For health outcomes, it was agreed that the focus of sedentary time research in older adults needs to include geriatric-relevant health outcomes, that there is insufficient evidence to quantify the dose–response relationship, that there is a lack of evidence on sedentary time from older adults in assisted facilities, and that evidence on the association between sedentary time and sleep is lacking. For interventions,research is needed to assess the impact that reducing sedentary time, or breaking up prolonged bouts of sedentary time has on geriatric-relevant health outcomes. Research priorities listed for each of these areas should be considered by researchers and funding agencies.This consensus statement has been endorsed by the following societies: Academy of Geriatric Physical Therapy, Exercise & Sports Science Australia, Canadian Centre for Activity and Aging, Society of Behavioral Medicine, and the National Centre for Sport and Exercise Medicine.

Objective: It is important for highly active individuals to easily and accurately assess their hydration level. Bioelectrical impedance (BIA) can potentially meet these needs but its validity in active individuals is not well established. We aim to validate total body water (TBW), extracellular water (ECW), and intracellular water (ICW) estimates obtained from 50 kHz BIA, bioelectrical impedance spectroscopy (BIS), and BIA-based models against dilution techniques in 2 populations: active adults and elite athletes.Methods:Active males (N= 28, 20–39 years) involved in recreational sports and elite athletes (females: N= 57, 16–35 years; males: N= 127, 16–38 years) participated in this study. TBW and ECW were assessed with deuterium and bromide dilution, respectively. ICW was assessed as their difference. Body water compartments were also assessed by BIA (BIA-101), BIS (model 4200), and BIA-based equations.Results:Small but significant differences were observed between alternative methods and the criterion in all subsamples. In female athletes, r2> 0.69, r2> 0.57, and r2> 0.65 were observed between methods in the TBW, ECW, and ICW estimates. In males, r2> 0.75, r2> 0.65, and r2> 0.68 were found between alternative and reference methods in the TBW, ECW, and ICW estimates, respectively, whereas for male recreational exercisers, r2> 0.58, r2> 0.73, and r2> 0.75 were observed. Pure errors ranged between 0.19 to 3.32 kg for TBW, 0.64 to 1.63 for ECW, and 1.98 to 2.64 in ICW. The highest limits of agreement (LoA) were observed in Van Loan and Mayclin equation and the BIA method, respectively, for TBW and ECW assessment and the lowest LoA were observed in BIS for both TBW and ECW estimates.Conclusions:The higher accuracy of BIS in predicting individual TBW, ECW, and ICW highlights its utility in water assessment of recreational and elite athletes.

Liver transplantation is nowadays the only effective answer to adjourn the outcome of functional limitations associated with familial amyloidotic polyneuropathy (FAP), a neurodegenerative disease characterized by sensory and motor polyneuropathies. Nevertheless, there is a detrimental impact associated with the after-surgery period on the fragile physical condition of these patients. Exercise training has been proven to be effective on reconditioning patients after transplantation. However, the effects of exercise training in liver transplanted FAP patients have not been scrutinized yet.

O Registo Nacional de Controlo do Peso (RNCP) estuda as características dos adultos portugueses com sucesso na manutenção do peso perdido. O presente trabalho compara os comportamentos e estratégias usadas no RNCP com os reportados por participantes do National Weight Control Registry(NWCR), nos EUA.

The purpose of the present study was to compare body surface area (BSA) estimates using two equations (Dubois and Dubois versus Livingston) and their respective effects on per cent body fat (%BF) obtained with two molecular approaches of body composition analysis, two-compartment (2C) and five-compartment (5C) models. Body composition data using the 2C model were studied in healthy adults, 432 women (body mass index (BMI): 28.3 ± 4.4 kg m?2) and 147 men (BMI: 26.8 ± 3.9 kg m?2), while another sample of 126 women (BMI: 30.4 ± 3.7 kg m?2) was evaluated using the 5C model. Measures of body volume (BV) assessed by air displacement plethysmography, bone mineral content by dual energy x-ray absorptiometry (DXA) and total-body water by deuterium dilution were used to estimate %BF with the 5C model. Comparison of means and linear regression analysis was performed. Using BSADubois, either in 2C and 5C models, BV and %BF estimates were significantly underestimated compared to results obtained using BSALivingston(p< 0.05). BMI was strongly associated with %BF differences using BSADuboisand BSALivingstonin both 2C (men: r= 0.90; women: r= 0.88) and 5C models (r= 0.88). Though %BFDuboisand %BFLivingstonwere strongly associated (r2= 1.000), some variability was observed on %BF differences using BSADuboisand BSALivingston. These findings suggest that BSA calculation is critical in BF estimation, supporting the use of a more accurate equation for non-obese and obese subjects.

ObjectiveThis report aimed to systematically review the evidence for a differential association between objective and self-reported physical activity and cardiorespiratory fitness on academic achievement.DesignSystematic review.Data sourcesStudies were identified from searches in Embase, Education Resources Information Center, PubMed, PsycINFO, SPORTdiscus and Web of Science databases from January 2000 to December 2016.Eligibility criteria for selecting studiesEligibility criteria included cross-sectional, longitudinal and interventional study designs. Outcomes included students’ school grade or a standardised test or measure of academic achievement. Explanatory variables were cardiorespiratory fitness and objective and self-reported physical activity. Inclusion criteria included school-aged children and adolescents aged–18 years (or students from primary to secondary school when student’s participants age was not described) and articles published in English, Portuguese or Spanish.ResultsA total of 51 articles met inclusion criteria: 41 cross-sectional, 2 intervention and 8 longitudinal studies. Results from 11 studies were inconsistent regarding the relationship between objectively measured physical activity and academic achievement. Ten of the 16 articles reported positive associations between self-reported physical activity and academic achievement. From the 22 studies that analysed the relationship between cardiorespiratory fitness and academic achievement, it was verified that they all generally support the beneficial effect of cardiorespiratory fitness on students’ academic achievement.ConclusionHigher cardiorespiratory fitness may be important to enhance children and adolescents’ health and, additionally, academic achievement. Due to a lack of consensus across studies, methodological issues associated with the assessment of physical activity should be considered when investigating physical activity and academic achievement.

Sedentary time (ST) is an important risk factor for a variety of health outcomes in older adults. Consensus is needed on future research directions so that collaborative and timely efforts can be made globally to address this modifiable risk factor. In this review, we examined current literature to identify gaps and inform future research priorities on ST and healthy ageing. We reviewed three primary topics:(1) the validity/reliability of self-report measurement tools, (2) the consequences of prolonged ST on geriatric-relevant health outcomes (physical function, cognitive function, mental health, incontinence and quality of life) and(3) the effectiveness of interventions to reduce ST in older adults.MethodsA trained librarian created a search strategy that was peer reviewed for completeness.ResultsSelf-report assessment of the context and type of ST is important but the tools tend to underestimate total ST. There appears to be an association between ST and geriatric-relevant health outcomes, although there is insufficient longitudinal evidence to determine a dose–response relationship or a threshold for clinically relevant risk. The type of ST may also affect health; some cognitively engaging sedentary behaviours appear to benefit health, while time spent in more passive activities may be detrimental. Short-term feasibility studies of individual-level ST interventions have been conducted; however, few studies have appropriately assessed the impact of these interventions on geriatric-relevant health outcomes, nor have they addressed organisation or environment level changes. Research is specifically needed to inform evidence-based interventions that help maintain functional autonomy among older adults.This consensus statement has been endorsed by the following societies: Academy of Geriatric Physical Therapy, Exercise & Sports Science Australia, Canadian Centre for Activity and Aging, Society of Behavioral Medicine, and the National Centre for Sport and Exercise Medicine.