Physical activity trajectories from childhood to late adolescence and their implications for health in young adulthood.

Physical activity has been associated with physical and mental health across the life course, yet few studies have used group-based trajectory modeling to examine the effect of longitudinal patterns of physical activity during childhood and adolescence on adult health outcomes. The Raine Study data from Gen2 follow-ups at 8, 10, 14, 17, 20, and 22 years collected between 1998 and 2014 were used. Latent class analysis identified trajectories using parent-reported physical activity for ages 8 to 17. Associations between trajectories and physical and mental health outcomes at ages 20 and 22 were explored, adjusting for current physical activity and considering sex interactions. Analysis in 2019 identified three trajectories: low (13%), mid (65%) and high (22%) physical activity (n = 1628). Compared to the low-activity trajectory, those in the high-activity trajectory had lower adiposity, insulin, HOMA-IR and fewer diagnosed disorders, higher HDL-cholesterol, and faster cognitive processing. For example, those in the high-activity trajectory had lower percent body fat at age 20 compared to those in the mid-activity (-4.2%, 95%CI: -5.8, -2.7) and low-activity (-9.5%, 95%CI: -11.7, -7.2) trajectories. Physical activity trajectories showed different associations between sexes for self-reported physical and mental health, BMI, systolic blood pressure, and depression symptoms. Being in the high- or mid-activity trajectory was associated with a more favorable cardiometabolic and mental health profile in young adulthood. Strategies are needed to help less active children to increase physical activity throughout childhood and adolescence to improve young adult health outcomes.

Evaluating the effectiveness of organisational-level strategies with or without an activity tracker to reduce office workers' sitting time: a cluster-randomised trial.

BACKGROUND: Office workers engage in high levels of sitting time. Effective, context-specific, and scalable strategies are needed to support widespread sitting reduction. This study aimed to evaluate organisational-support strategies alone or in combination with an activity tracker to reduce sitting in office workers. METHODS: From one organisation, 153 desk-based office workers were cluster-randomised (by team) to organisational support only (e.g., manager support, emails; 'Group ORG', 9 teams, 87 participants), or organisational support plus LUMOback activity tracker ('Group ORG + Tracker', 9 teams, 66 participants). The waist-worn tracker provided real-time feedback and prompts on sitting and posture. ActivPAL3 monitors were used to ascertain primary outcomes (sitting time during work- and overall hours) and other activity outcomes: prolonged sitting time (≥30 min bouts), time between sitting bouts, standing time, stepping time, and number of steps. Health and work outcomes were assessed by questionnaire. Changes within each group (three- and 12 months) and differences between groups were analysed by linear mixed models. Missing data were multiply imputed. RESULTS: At baseline, participants (46 % women, 23-58 years) spent (mean ± SD) 74.3 ± 9.7 % of their workday sitting, 17.5 ± 8.3 % standing and 8.1 ± 2.7 % stepping. Significant (p < 0.05) reductions in sitting time (both work and overall) were observed within both groups, but only at 12 months. For secondary activity outcomes, Group ORG significantly improved in work prolonged sitting, time between sitting bouts and standing time, and overall prolonged sitting time (12 months), and in overall standing time (three- and 12 months); while Group ORG + Tracker, significantly improved in work prolonged sitting, standing, stepping and overall standing time (12 months). Adjusted for confounders, the only significant between-group differences were a greater stepping time and step count for Group ORG + Tracker relative to Group ORG (+20.6 min/16 h day, 95 % CI: 3.1, 38.1, p = 0.021; +846.5steps/16 h day, 95 % CI: 67.8, 1625.2, p = 0.033) at 12 months. Observed changes in health and work outcomes were small and not statistically significant. CONCLUSIONS: Organisational-support strategies with or without an activity tracker resulted in improvements in sitting, prolonged sitting and standing; adding a tracker enhanced stepping changes. Improvements were most evident at 12 months, suggesting the organisational-support strategies may have taken time to embed within the organisation. TRIAL REGISTRATION: Australian New Zealand Clinical Trial Registry: ACTRN12614000252617 . Registered 10 March 2014.

An active video game intervention does not improve physical activity and sedentary time of children at-risk for developmental coordination disorder: a crossover randomized trial.

BACKGROUND: Children with developmental coordination disorder (DCD) are highly inactive and sedentary. The purpose of this study was to assess the impact of a home-based active video game intervention on objectively measured physical activity and sedentary behaviour in children at risk for DCD. METHODS: In a crossover randomized clinical trial, 21 children (mean age 11.0, SD 1.0; n = 11 girls) in Perth, Western Australia participated in two 16-week periods: no active video games (AVGs) control period and AVGs intervention period. Two active input consoles were provided to participants along with a selection of non-violent AVGs for participants to play at home. Participants wore accelerometers at baseline and following each period to determine minutes of sedentary, light, moderate and vigorous times in addition to self-reported types of activities in a diary. Linear mixed models, adjusted for the order of periods, compared physical activity and sedentary time during the last week of each period. RESULTS: There were no significant differences between the intervention and control periods in time spent in sedentary (decrease of -1.0 min/day during the intervention period, 95%CI -12.1, 10.1), light (increase of 2.2 min/day, 95%CI -8.8, 13.2), moderate (decrease of 0.7 min/day, 95%CI -4.6, 3.3) or vigorous (decrease of -0.6 min/day, 95%CI -1.6, 0.4). CONCLUSIONS: Among children at risk for DCD, participating in this AVG intervention did not improve objectively measured physical activity and sedentary time.

Overweight adolescents eat what? And when? Analysis of consumption patterns to guide dietary message development for intervention.

BACKGROUND: Little is known about overweight adolescent dietary consumption patterns, with challenges to collecting meaningful data making it difficult to develop targeted obesity interventions. The present study aimed to examine the timing and consumption of fruit, vegetables and junk food by time of the day and day of the week. METHODS: Overweight adolescents (n = 61), aged 12-16 years, completed 3-day food records. Negative binomial and binary logistic regression using generalised estimating equations were used to compare the amount and likelihood of the consumption of each food group between time periods. RESULTS: Overweight adolescent girls were more likely to eat fruit on weekdays than weekends [odds ratio (OR) = 5.0. P < 0.001], as were boys (OR = 2.5, P = 0.034). Adolescents consumed more fruit at school than other meals [girls: incident rate ratio (IRR) = 7.5, P < 0.001; boys: IRR = 4.0, P = 0.050]. Weekday dinner was the meal where girls were most likely to consume vegetables (OR = 3.0, P = 0.009) and when boys consumed the most vegetables (IRR = 30.9, P = 0.006). Fast food consumption was most likely for girls at dinner on the weekend (OR = 9.6, P = 0.042), whereas fast food intake for boys increased overall on the weekend (IRR = 3.6, P = 0.001). Intake of 'other junk' (e.g. crisps) peaked during school hours for girls (IRR = 7.2, P < 0.001) and sugar-sweetened beverage consumption increased for boys on the weekend (IRR = 3.3, P = 0.001). Overall, trends in fruit intake showed opposing times for high and low consumption compared to vegetable intake. CONCLUSIONS: These results represent the next step in using time of day and day of week consumption patterns to develop targeted, evidence-based dietary messages for interventions in overweight adolescents.

Genetic variation in the beta-2 adrenergic receptor is associated with chronic musculoskeletal complaints in adolescents.

BACKGROUND: There is significant evidence to suggest that psychological and stress-related factors are important predictors of the onset of chronic widespread pain (CWP) and fibromyalgia (FM). The hypothalamic-pituitary-adrenal axis, together with the efferent sympathetic/adrenomedullary system, influence all body organs (including muscles) during short- and long-term threatening stimuli. The aim of this study was to investigate the relationship between genetic variants in adrenergic candidate genes and chronic musculoskeletal complaints (MSCs) in adolescents. METHODS: Adolescents from the Western Australian Pregnancy (Raine) Cohort attending the 17-year cohort review completed a questionnaire containing a broad range of psychosocial factors and pain assessment (n = 1004). Blood samples were collected for DNA extraction and genotyping. Genotype data was obtained for 14 single nucleotide polymorphisms (SNPs) in two candidate genes - beta-2 adrenergic receptor (ADRB2) and catecholamine-O-methyltransferase (COMT). Haplotypes were reconstructed for all individuals with genotype data. RESULTS AND CONCLUSION: Both female gender and poor mental health were associated with (1) an increased risk for chronic, disabling comorbid neck and low back pain (CDCP); and (2) an increase in the number of areas of pain. Of the 14 SNPs evaluated, only SNP rs2053044 (ADRB2, recessive model) displayed an association with CDCP [odds ratio (OR) = 2.49; 95% confidence interval (CI) = 1.25, 4.98; p = 0.01] and pain in three to four pain areas in the last month (OR = 1.86; 95% CI = 1.13, 3.06; p = 0.02). These data suggest that genetic variants in ADRB2 may be involved in chronic MSCs.

'I am absolutely shattered': the impact of chronic low back pain on Australian Aboriginal people.

BACKGROUND: Aboriginal people in Australia have been uniquely identified as less susceptible to chronic low back pain (CLBP) disability when compared to non-Aboriginal populations, reportedly due to cultural beliefs about pain. A qualitative, culturally secure research approach was used to explore this assumption. METHODS: In-depth interviews were undertaken with 32 Aboriginal men and women with CLBP in regional and remote areas of Western Australia. Interviews were conducted collaboratively with male and female Aboriginal co-investigators, and with the support of local Aboriginal community organizations. A primary focus was to investigate the impact of CLBP from the perspective of Aboriginal people living with the condition. RESULTS: The experience of CLBP was found to be multidimensional, impacting on activities of daily life, employment, sport and family participation, emotional and cultural well-being. CONCLUSIONS: Contrary to previous assumptions, CLBP is profoundly disabling for some Aboriginal people and a priority health concern. Issues of gender, cultural obligations and the emotional consequences of CLBP are important consideration for health care. These findings, and the contextual approach used to gain an in-depth understanding of CLBP, may be relevant to populations elsewhere.

Neck/shoulder pain is more strongly related to depressed mood in adolescent girls than in boys.

A cross-sectional study of 1258, 14 year old girls and boys used self-report and physical examination measures to assess neck/shoulder pain in the last month, depressed mood, physical fitness, body composition, self-efficacy, global self-worth, family functioning and social advantage. The data was used to compare the relationship between depressed mood and neck/shoulder pain (NSP) in adolescent girls and boys. The prevalence of NSP in girls (34%, 211/621) was significantly greater than in boys (21%, 134/637; p < .001). After controlling for covariates, girls with medium (OR = 4.28; CI = 2.31-7.92; p < .001) and high depressed mood (OR = 8.63; CI = 4.39-16.98; p < .001) were significantly more likely to report NSP than girls with low depressed mood. Depressed mood was also a significant correlate of NSP in boys after controlling for covariates, although the association was substantially weaker (OR = 2.44; CI = 1.29-4.61; p < .001). After controlling for relevant biological, psychological and social covariates, depressed mood was a significant correlate of NSP in both sexes; but the association between depressed mood and NSP was significantly stronger for girls than for boys.

Bone health and back pain: what do we know and where should we go?

Bone health is generally not considered in patients who present with chronic back pain. Nonetheless, bone health and back pain share common genetic and environmental correlates suggesting a co-dependence. Evidence exists for a relationship between back pain and impaired bone health. Here we present the evidence, theoretic framework and clinical relevance. Bone health and back pain are important determinants of musculoskeletal health. Back pain experienced in youth is a risk factor for future back pain, while suboptimal bone health during development increases the risk of skeletal fragility in later life. Generally, bone health is not considered in patients with chronic back pain who do not demonstrate other well-recognised bone health risk factors or associated conditions. Nonetheless, evidence suggests that back pain and impaired bone health share common environmental and genetic correlates, indicating that bone health ought to be considered in the context of back pain in otherwise healthy individuals. This review describes the likely mechanisms explaining the relationship between back pain and impaired bone health, evidence concerning the relationship and suggestions for future research. A narrative literature search was conducted using CINAHL, Medline, PubMed and Web of Science electronic databases. A history of back pain is associated with decreased bone mineral density in adults, yet this tends to be site-specific. No studies were identified examining this association in youth, yet the negative effects of childhood skeletal trauma and obesity on bone and spinal health provide indirect evidence for an association. Further research is required to clarify the impact of back pain on bone health at different lifespan stages using prospective cohort designs.

A comparison of posture and muscle activity during tablet computer, desktop computer and paper use by young children.

Computers are now widely used by children. Tablet computers are becoming widely available and promoted for use by school children. The primary objective of this study was to compare the posture and muscle activity of children using a tablet computer to the posture and muscle activity of children using a desktop computer and paper technology. Eighteen children (mean age 5.6 years) performed a colouring-in task in tablet, desktop and paper conditions. 3-D posture and muscle activity around the neck and shoulder was assessed. Tablet computer use was similar to paper use, with less neutral spinal posture, more elevated scapular posture and greater upper trapezius and cervical erector spinae activity. This was offset by greater variability of posture and muscle activity. Tablet computer use clearly results in different musculoskeletal stresses than desktop computer use. Computer use guidelines need to be appropriate to traditional and emerging technologies. Tablet computers are being promoted for use by adults and children. However, the physical impact of using this type of technology is not known. The findings of this study provide the first tablet-specific evidence to inform guidelines on wise use of tablet computers by children.

The association between information and communication technology exposure and physical activity, musculoskeletal and visual symptoms and socio-economic status in 5-year-olds.

BACKGROUND: Increasing use of computers by children has raised concerns over the potential impact on their cognitive, social, educational, visual and physical development. Despite this concern, there are no large-scale studies relating the use of computers to specific health indicators in children as they reach school age. METHODS: A cross-sectional analysis of 1600 5-year-old Western Australian children participating in a longitudinal cohort study was conducted to ascertain their computer use, other activities (watching television and videos, playing electronic games, reading and looking at books, drawing on paper and moderate to vigorous physical activity), and specific health indicators. RESULTS: More than half (56%) of the children used computers each week. Computer use was significantly related to TV viewing (OR 1.97 weekday) and electronic game use (console games OR 2.48 weekday, 1.81 weekend; hand-held games OR 1.88 weekend) and negatively associated with vigorous physical activity on weekends (OR 0.72). Computer use was also significantly related to socio-economic indicators such as the mother being older (40+ years, OR 1.70 weekend, 1.73 weekday), tertiary educated (OR 1.63 weekend) and studying (OR 1.52 weekend, 1.41 weekday). Almost 1% children were reported to have complained of tired or sore muscles, and 2.2% had complained of tired or sore eyes, after watching television or using a computer. CONCLUSION: A substantial proportion of 5-year-old Western Australian children are using computers. Computer use was related to other sedentary activities and less vigorous activity. While musculoskeletal and vision problems are not widespread, their presence and the sedentary nature of computer use is of public health concern.

The inter-examiner reliability of a classification method for non-specific chronic low back pain patients with motor control impairment.

The importance of classifying chronic low back pain (LBP) patients into homogeneous sub-groups has recently been emphasized. This paper reports on two studies examining clinicians ability to agree independently on patients' chronic LBP classification, using a novel classification system (CS) proposed by O'Sullivan. In the first study, a sub-group of 35 patients with non-specific chronic LBP were independently classified by two 'expert' clinicians. Almost perfect agreement (kappa-coefficient 0.96; %-of-agreement 97%) was demonstrated. In the second study, 13 clinicians from Australia and Norway were given 25 cases (patients' subjective information and videotaped functional tests) to classify. Kappa-coefficients (mean 0.61, range 0.47-0.80) and %-of-agreement (mean 70%, range 60-84%) indicated substantial reliability. Increased familiarity with the CS improved reliability. These studies demonstrate the reliability of this multi-dimensional mechanism-based CS and provide essential evidence in a multi-step validation process. A fully validated CS will have significant research and clinical application.

Physical and psychosocial aspects of the learning environment in information technology rich classrooms.

This paper reports on a study of environments in emerging Internet classrooms. At issue for this study is to what extent these 'technological classrooms' are providing a positive learning environment for students. To investigate this issue, this study involved an evaluation of the physical and psychosocial environments in computerized school settings through a combination of questionnaires and inventories that were later cross-referenced to case studies on a subset of these classrooms. Data were obtained from a series of physical evaluations of 43 settings in 24 school locations in British Columbia, Canada and Western Australia. Evaluations consisted of detailed inventories of the physical environment using the Computerised Classroom Environment Inventory (CCEI): an instrument developed specifically for this study. Data on psychosocial aspects of the environment were obtained with the What is Happening in this Class? (WIHIC) questionnaire administered to 1404 high school students making routine use of these computerized classrooms. Potential deficiencies in the physical environment of these locations included problems with individual workspaces, lighting and air quality, whereas deficiencies in the psychosocial environment were confined to the dimension of Autonomy. Further analysis of these classroom environment data indicated that student Autonomy and Task orientation were independently associated with students' Satisfaction with learning and that many physical (e.g. lighting and workspace dimensions) and psychosocial factors (e.g. students' perceptions of Co-operation and Collaboration) were also associated. The results provide a descriptive account of the learning environment in 'technology-rich' classrooms and, further, indicate that ergonomic guidelines used in the implementation of IT in classrooms may have a positive influence on the learning environment.

A comparison of risk assessment of single and combination manual handling tasks: 2. Discomfort, rating of perceived exertion and heart rate measures.

Although many manual handling activities involve combinations of pull, lift, carry, lower and push, there are few reports of investigation of how to assess the risk in these combination tasks. Two strategies have been suggested in the literature for estimating the risk in a combination task based on the measures of the separate components of that task. The aim of the study was to compare the risks assessed in single manual handling tasks with those in combination tasks. Ratings of discomfort, exertion and heart rate were collected from nine male and nine female students, performing combination and single tasks. Combination tasks consisted of sequences of pull, lift, carry, lower and push tasks. Combination tasks were performed at 1.min-1 and 3.min-1 whilst single tasks (lift, lower, push, pull and carry) were performed at 3.min-1 and 6.min-1. The rating of exertion and heart rate for each combination task was compared to the exertion rating and heart rate of the single tasks which comprised the combination task using repeated measures analysis of variance with specified contrasts. Similar comparisons for the discomfort data were performed using Friedman and Wilcoxon tests. In at least one of the twelve comparisons performed for each dependent variable, the combination task value was significantly different to each single task value. The differences occurred regardless of whether the most critical single task value or an average of all single task values was used. It was concluded that the risk in combination manual tasks can not be accurately assessed by using estimates from discomfort, exertion ratings and heart rate measures of single tasks.

A comparison of risk assessment of single and combination manual handling tasks: 1. maximum acceptable weight measures.

Many manual handling activities involve combinations of pull, lift, carry, lower and push, yet few studies have investigated how to assess the risk of such combination tasks. Most recommendations assume that a combination task can be split into its components for assessment. The aim of this study was to compare the risks assessed in single manual handling tasks with those in combination tasks. Nine male and nine female students participated in a study to determine Maximum Acceptable Weights (MAWs) in single and combination tasks at different frequencies (1 min-1 and 3 min-1 for combination tasks and 3 min-1 and 6 min-1 for single tasks) and heights (floor, knuckle, shoulder). Combination tasks consisted of one each of the single tasks (pull, lift, carry, lower and push). The MAW of each combination task was compared to the MAWs of the single tasks of which it was composed using repeated measures analysis of variance with specified contrasts. In at least one of the 12 comparisons each single task MAW was found to be different from its related combination task MAW. It was concluded that the current use of single task MAWs to estimate the risk in combination tasks was unacceptable. Prediction models for combination task MAWs based on single tasks MAWs were also developed, using step-wise regression. Although coefficients of determination of around 0.8 were achieved it was argued that owing to their situation-specific nature the prediction of combination task risk using single task MAWs was likely to result in unacceptable risk errors.

An investigation of discomfort experienced by dental therapists and assistants at work.

Dental therapists and assistants frequently experience musculoskeletal complaints associated with their work. In order to plan and implement programmes aimed at reducing the number of these complaints, the level and location of physical discomfort experienced by dental workers at work was documented to identify potential problem areas associated with dental practice.

Work-associated back problems: measurement problems.

Work-associated back problems are a major problem in the British National Health Service. Attempts to reduce the problem can only be judged when effective measuring and monitoring systems are available. This article highlights the problems associated with some currently available systems and describes a new system developed especially for the health service. Examples of the use of the new system are given to demonstrate its potential.

Work-associated back problems: collaborative solutions.

Work-associated back problems are a major health issue for which the traditional approaches of manual skills training and worker selection have demonstrated little effect. The common alternative, direct ergonomics intervention, risks work group resentment and non-compliance problems. This paper describes a new ergonomics training approach which changes the role and content of training to facilitate staff and management collaboration.