Relationship between weight status and cognition in children: A mediation analysis of physical fitness components

ABSTRACT

Cross-sectional study aimed to analyse differences in cognitive performance across fitness components categories (cardiorespiratory fitness [CRF], speed-agility and muscular fitness [MF]) and weight status in children, and to determine whether physical fitness mediates the association between body mass index (BMI) and cognitive performance. Fitness components and BMI were measured using standard procedures in 630 children aged 5-to-7 years from the provinces of Cuenca and Ciudad Real, Spain. BADyG was used to assess cognitive performance. We used ANCOVA models to test mean differences in cognition scores by BMI and fitness categories. Hayes’s PROCESS macro was used for mediation analyses. Children with normal weight scored better in spatial factor and general intelligence than their overweight/obese peers (p < 0.05), but differences were attenuated when controlling for CRF (p > 0.05). Children with better results in CRF and speed-agility scored better in all cognitive dimensions even after controlling for BMI (p < 0.05). Similarly, children with high MF obtained better scores in verbal factor (p < 0.05). All fitness components acted as mediators of the relationship between BMI and general intelligence (p < 0.05). These findings highlight the crucial role of fitness in minimising the negative effect of excess weight on children’s cognition.

Abbreviations: BMI: Body mass index; CRF: Cardiorespiratory fitness; MF: Muscular fitness; BADyG E1: Battery of general and differential aptitudes; SES: Socioeconomic status; SD: Standard deviation; IE: Indirect effect     

Inter-participant variability in daily physical activity and sedentary time among male youth sport footballers: independent associations with indicators of adiposity and cardiorespiratory fitness

Participation in youth sport is assumed to promote and contribute towards more physically active lifestyles among children and adolescents. The aim of this study was to examine inter-participant variability in objectively measured habitual physical activity (PA) behaviours and sedentary time among youth sport participants and their implications for health. One-hundred-and-eighteen male youth sport footballers (Mean ± s = 11.72 ± 1.60) wore a GT3X accelerometer for 7 days. Average daily PA [min · day^?1, in light (LPA), moderate (MPA), vigorous (VPA) and combined moderate-to-vigorous (MVPA)] and sedentary time were calculated. Participants’ body mass index adjusted for age and sex (BMI–standard deviation score), per cent body fat (BF%), waist circumference and cardiorespiratory fitness were assessed. Results revealed that variability in daily PA behaviours and sedentary time (min · day^?1) was associated with BMI–standard deviation score [VPA (?), MVPA (?)], BF% [sedentary time (+), VPA (?), MVPA (?)], waist circumference [sedentary time (+), LPA (?)] and cardiorespiratory fitness [sedentary time (?), MPA (+), VPA (+), MVPA (+)]. Whilst sedentary time and MVPA were not related to health outcomes independent of one another, associations with markers of adiposity and cardiorespiratory fitness were stronger for sedentary time. Sedentary time was also significantly positively related to waist circumference independent of VPA. Results demonstrate inter-participant variability in habitual PA and sedentary time among youth sport participants which holds implications for their health. Thus, promoting PA and, in particular, reducing sedentary time may contribute towards the prevention of adverse health consequences associated with a physically inactive lifestyle for children and adolescents active in the youth sport context.     

Mediating effect of aerobic fitness on the association between physical activity and academic achievement among adolescents: A cross-sectional study in Okinawa,Japan

The purpose of this study was to examine the potential role of aerobic fitness (AF) as a mediator of the association between physical activity (PA) and academic achievement (AA) among Japanese junior high school students. A cross-sectional data was collected from 608 7th grade students enrolled at five public junior high schools in two suburban municipalities in Okinawa, Japan. Self-reported PA was assessed using the Patient-Centred Assessment and Counselling for Exercise plus Nutrition questionnaire. The 20-meter shuttle run test was performed to determine AF. AA was evaluated using the overall grade point average. Family structure, parental education level, and achievement motives were the self-reported covariates. The results of the bootstrapped mediation analysis indicated that PA had a direct effect on AF, which in turn influenced the AA among boys. After adjusting for AF, the association between PA and AA disappeared while the association of AF with AA still remained. However, neither PA nor AF was associated with the AA of girls. Therefore, the hypothesis that AF might mediate the relationship between PA and AA was supported for boys. Promoting AF, as a result of engaging to PA could positively influence AA particularly in boys.     

Mediating effects of motor performance,cardiorespiratory fitness,physical activity,and sedentary behaviour on the associations of adiposity and other cardiometabolic risk factors with academic achievement in children

We investigated the associations of cardiometabolic risk factors with academic achievement and whether motor performance, cardiorespiratory fitness, physical activity, or sedentary behaviour mediated these associations. Altogether 175 children 6–8 years-of-age participated in the study. We assessed body fat percentage (BF%), waist circumference, insulin, glucose, triglycerides, HDL cholesterol, and systolic and diastolic blood pressure, leptin, alanine aminotransferase, and gamma-glutamyltransferase (GGT). Reading fluency, reading comprehension, and arithmetic skills were assessed using standardized tests. Speed/agility, balance, and manual dexterity test results were used to calculate motor performance score and physical activity was assessed by combined heart rate and movement sensor and cardiorespiratory fitness by maximal cycle ergometer test. In boys, BF% was inversely associated with reading fluency (β = ?0.262, P = 0.007) and reading comprehension (β = ?0.216, P = 0.025). Motor performance mediated these associations. Leptin was inversely related to reading fluency (β = ?0.272, P = 0.006) and reading comprehension (β = ?0.287, P = 0.003). The inverse association of leptin with reading fluency was mediated by motor performance. In girls, GGT was inversely associated with reading fluency independent of confounders (β = ?0.325, P = 0.007). The inverse association of BF% with academic achievement among boys was largely explained by motor performance. Leptin in boys and GGT in girls were inversely associated with academic achievement independent of confounding factors.     

The effect of exercise and diet on mental health and quality of life in middle-aged individuals with elevated risk factors for cardiovascular disease.

Mental health and quality of life were assessed before and after a one-year exercise and diet intervention among 219 healthy individuals, aged 41-50 years, with elevated risk factors for cardiovascular disease. The participants were randomized to four groups: diet (n = 55), diet and exercise (n = 67), exercise (n = 54) and no active intervention (n = 43). Quality of life was measured with one eight-item scale and two one-item scales. Mental health was measured by the General Health Questionnaire (30-item version). Depression, anxiety, feelings of competence and self-esteem, coping and social dysfunction were measured using subscales of the General Health Questionnaire. Somatic anxiety was measured by the anxiety subscale of the Symptom Check List-90. Exercise improved the total GHQ scores, perceived competence/self-esteem, and coping as measured by the GHQ subscales. There were no significant effects of diet or exercise on quality of life, depression or anxiety. A high rate of participation in the exercise programme (>70%) was associated with greater improvements in total GHQ scores, anxiety, perceived competence/self-esteem and coping.     

Association of physical activity with risk of chronic kidney disease in China:A population-based cohort study

Background:Information on the association between physical activity(PA) and the risk of chronic kidney disease(CKD) is limited.We aimed to explore the associations of total,domain-specific,and intensity-specific PA with CKD and its subtypes in China.Methods:The study included 475,376 adults from the China Kadoorie Biobank aged 30-79 years during 2004-2008 at baseline.An interviewer-administered questionnaire was used to collect the information about PA,which was quantified as metabolic equivalen...     

Association of leisure time and occupational physical activity with obesity and cardiovascular risk factors in Chile

ABSTRACT

The aim of this study was to investigate the association between physical activity (PA), both occupational (OPA) and during leisure time (LTPA), with obesity and cardiovascular risk factors in Chilean adults. 5,157 participants from the Chilean National Health Survey 2009–2010 were included in this study. OPA and LTPA levels were assessed using the Global Physical Activity Questionnaire. The association between both PA with obesity and cardiovascular risk factors was determined using logistic regression. Our findings showed a significant trend between higher LTPA and lower odds for obesity (OR 0.64 [95% CI: 0.53; 0.76], central obesity 0.52 [0.44; 0.61]) and other cardiovascular risk factors including diabetes (OR: 0.72 [0.55; 0.94]), hypertension (OR: 0.59 [0.50; 0.71]) and metabolic syndrome (OR: 0.62 [0.50; 0.78]). In contrast, OPA was only associated with lower odds of diabetes (OR: 0.79 [0.65; 0.98]) and hypertension (0.85 [0.74; 0.98]). In conclusion, LTPA was associated with a lower risk of all major cardiovascular risk factors, whereas OPA was only associated with a lower risk of diabetes and hypertension.     

Association of physical activity with risk of metabolic syndrome: findings from a cross-sectional study conducted in rural area,Nantong, China

The prevalence of metabolic syndrome increases rapidly worldwide, and its association with physical activity (PA) varies with race and lifestyles. Little is known about the association in rural China. The Nantong Metabolic Syndrome Study recruited 13,505 female and 6997 male participants in 2007 and 2008. Socio-demographic characteristics, and physiological and behavioural data were collected. Logistic regression model was applied to estimate associations of metabolic syndrome and its components with different PAs. The overall metabolic syndrome prevalence was 21.6% in current study. Increasing total PA or moderate-to-vigorous-intensity occupational PA was associated with decreasing 5%–60% risk of having metabolic syndrome and abnormal metabolic syndrome components in both genders. An association between leisure-time PA and blood pressure was found in men, but no associations between leisure-time PA and metabolic syndrome components were found in women. Commuting PA, such as walking and taking bus, by bicycle and walking only, was associated with decrease of 20%–45% risk of several abnormal metabolic syndrome components in women. This study provides information for future investigation into the nature of these associations so that recommendations can be developed to reduce the prevalence of metabolic syndrome and its components among rural population in China.     

Running into trouble: constructions of danger and risk in girls' access to outdoor space and physical activity

This paper considers girls' participation in running and other outdoor physical activities in their local areas in London, UK. The paper is concerned with the operation of risk discourses in and around this participation and looks at the way that such discourses impacted on girls' opportunities to take part in physical activities that required outdoor space. Drawing on data from longitudinal research into girls' participation in sport and physical activity, the findings suggested that girls, in particular, were subject to risk discourses around their participation in physical activities which constructed the girls as ‘weak’, and ‘vulnerable’. I look at the ways in which girls understood these messages and how they came to define certain spaces and activities as either ‘safe’ or ‘unsafe’. I look in particular at how girls were able to resist certain constructions of their embodied physical capacities and also at the ways in which this was constrained by specific incidences of sexual harassment.     

Leisure-time physical activity and all-cause mortality and cardiovascular disease in adults with type 2 diabetes:Cross-country comparison of cohort studies

Purpose:This study aimed to quantify the dose-response association and the minimal effective dose of leisure-time physical activity(PA) to prevent mortality and cardiovascular disease in adults with type 2 diabetes.Methods:Cross-country comparison of 2 prospective cohort studies including 14,913 and 17,457 population-based adults with type 2 diabetes from the UK and China.Baseline leisure-time PA was self-reported and categorized by metabolic equivalent hours per week(MET-h/week) according to Wo...     

Effects of strength training on physical fitness and sport-specific performance in recreational,sub-elite,and elite rowers: A systematic review with meta-analysis

ABSTRACT

The purpose of this systematic review with meta-analysis was to examine the effects of strength training (ST) on selected components of physical fitness (e.g., lower/upper limb maximal strength, muscular endurance, jump performance, cardiorespiratory endurance) and sport-specific performance in rowers. Only studies with an active control group were included if they examined the effects of ST on at least one proxy of physical fitness and/or sport-specific performance in rowers. Weighted and averaged standardized mean differences (SMD) were calculated using random-effects models. Subgroup analyses were computed to identify effects of ST type or expertise level on sport-specific performance. Our analyses revealed significant small effects of ST on lower limb maximal strength (SMD = 0.42, p = 0.05) and on sport-specific performance (SMD = 0.32, p = 0.05). Non-significant effects were found for upper limb maximal strength, upper/lower limb muscular endurance, jump performance, and cardiorespiratory endurance. Subgroup analyses for ST type and expertise level showed non-significant differences between the respective subgroups of rowers (p ≥ 0.32). Our systematic review with meta-analysis indicated that ST is an effective means for improving lower limb maximal strength and sport-specific performance in rowers. However, ST-induced effects are neither modulated by ST type nor rowers’ expertise level.     

Associations of total sedentary time,screen time and non-screen sedentary time with adiposity and physical fitness in youth: the mediating effect of physical activity

The aims of the present study were: i) to examine the associations of total accelerometer-based sedentary time (ST) and specific-domain self-reported ST (i.e., screen-based, educational-based, social-based, and other-based ST) with adiposity and physical fitness in youth; and ii) to analyse the mediation effect of physical activity (PA) on associations.

This study was conducted with 415 children (9.1 ± 0.4 years) and 853 adolescents (13.6 ± 1.6 years) in Spain during 2011–2012. Total ST and PA were assessed by accelerometry. Leisure-time spent in twelve sedentary behaviours was self-reported. Adiposity and physical fitness was measured following the ALPHA battery for youth.

Total accelerometer-based ST was positively associated with global adiposity score in children, and negatively associated with global physical fitness score in children and adolescents; but relationships were not independent of PA. PA mediated all associations of accelerometer-based and self-reported ST with adiposity or physical fitness in children. Conversely, screen-, educational-, social-, and other-based ST were negatively related to physical fitness in adolescents, independently of PA.

These findings give an impetus to developing effective strategies for specifically promoting PA in children and for increasing PA while reducing ST in adolescents in order to produce improvements on adiposity and physical fitness.     

Land of confusion: unpacking the relationship between physical activity and well-being in individuals living with osteoporosis

Whether physical activity is linked with improvements in well-being in individuals living with osteoporosis remains a source of debate within the literature. The purpose of this review is to synthesize relevant literature to more fully address the relationship between physical activity and well-being in individuals living with osteoporosis. Guided by study inclusion criteria, a total of 17 quantitative studies were coded for review. Considerable heterogeneity was found between studies when examining the well-being instrumentation and physical activity characteristics used by study authors. A central finding was that physical activity is associated with increased well-being across the bulk of existing studies retained for analysis, with benefits noted particularly for markers linked to physical functioning. This review further highlights how decisions made by researchers have implications for study conclusions and can render any synthesis of this literature a challenge. As such, recommendations for future studies are advanced that span issues linked to the measurement and conceptualization of well-being and physical activity and the analytic decisions made by researchers. Finally, heightened attention to the mechanisms through which physical activity may be linked with well-being outcomes is needed. Given the importance of well-being outcomes, researchers are encouraged to adopt these recommendations in an effort to advance the literature.     

Effect and feasibility of wearable physical activity trackers and pedometers for increasing physical activity and improving health outcomes in cancer survivors: A systematic review and meta-analysis

Purpose:This systematic review and meta-analysis aimed to evaluate the effect of wearable devices for improving physical activity and healthrelated outcomes in cancer survivors.Methods:CINAHL,Cochrane,Ebscohost,MEDLINE,Pubmed,ProQuest Health and Medical Complete,ProQuest Nursing and Allied Health Source,ScienceDirect,and SPORTDiscus databases were searched for randomized controlled trials published before September 1,2020,that evaluated interventions involving wearable devices in cancer survivors.Standardized mean differences(SMDs)were calculated to assess effects on physical activity and health-related outcomes.Subgroup analyses were conducted to assess whether the effects differed by interventions and cancer characteristics.Risk of bias was assessed using the Cochrane risk of bias tool.Results:Thirty-five trials were included(breast cancer,n=15,43%).Intervention durations ranged between 4 weeks and 1 year.Most trials(n=25,71%)involved pedometer-based physical activity interventions.Seven(20%)involved Fitbit-based interventions,and 3(9%)involved other wearable physical activity trackers(e.g.,Polar,Garmin).Compared to usual care,wearable devices had moderate-to-large effects(SMD range 0.54-0.87,p<0.001)on moderate-intensity physical activity,moderate-to-vigorous-intensity physical activity,total physical activity,and daily steps.Compared to usual care,those in the intervention had higher quality of life,aerobic fitness,physical function,and reduced fatigue(SMD range=0.18-0.66,all p<0.05).Conclusion:Wearable physical activity trackers and pedometers are effective tools that increase physical activity and improve health-related outcomes in individuals with cancer.Identifying how these devices can be implemented for longer-term use with other intervention components remains an area for future research.     

A comparison of accelerometry analysis methods for physical activity in older adult women and associations with health outcomes over time

ABSTRACT

This study compared five different methods for analyzing accelerometer-measured physical activity (PA) in older adults and assessed the relationship between changes in PA and changes in physical function and depressive symptoms for each method. Older adult females (N = 144, M_age = 83.3 ± 6.4yrs) wore hip accelerometers for six days and completed measures of physical function and depressive symptoms at baseline and six months. Accelerometry data were processed by five methods to estimate PA: 1041 vertical axis cut-point, 15-second vector magnitude (VM) cut-point, 1-second VM algorithm (Activity Index (AI)), machine learned walking algorithm, and individualized cut-point derived from a 400-meter walk. Generalized estimating equations compared PA minutes across methods and showed significant differences between some methods but not others; methods estimated 6-month changes in PA ranging from 4 minutes to over 20 minutes. Linear mixed models for each method tested associations between changes in PA and health. All methods, except the individualized cut-point, had a significant relationship between change in PA and improved physical function and depressive symptoms. This study is among the first to compare accelerometry processing methods and their relationship to health. It is important to recognize the differences in PA estimates and relationship to health outcomes based on data processing method.

Abbreviation: Machine Learning (ML); Short Physical Performance Battery (SPPB); Center of Epidemiologic Studies Depression Scale (CES-D); Physical Activity (PA); Activity Index (AI); Activities of Daily Living (ADL)