Weight status associations with physical activity intensity and physical self-perceptions in 10- to 11-year-old children

The study examined associations between children's weight status, physical activity intensity, and physical self-perceptions. Data were obtained from 409 children (224 girls) aged 10-11 years categorized as normal-weight or overweight/obese. Physical activity was assessed using accelerometry, and children completed the Physical Self-Perception Profile. After controlling for the effects of age, maturation, and socioeconomic status vigorous physical activity was significantly associated with normal-weight status among boys (OR = 1.13, p = .01) and girls (OR = 1.13, p = .03). Normal-weight status was significantly associated with perceived Physical Condition (Boys: OR = 5.05, p = .008; Girls: OR = 2.50, p = .08), and Body Attractiveness (Boys: OR = 4.44, p = .007; Girls: OR = 2.56, p = .02). Weight status of 10-11 year old children was significantly associated with time spent in vigorous physical activity and self-perceptions of Body Attractiveness and Physical Condition.     

Promotion of physical activity in children

PURPOSE OF REVIEW: Promotion of physical activity continues to be recommended as an essential component of obesity treatment and prevention interventions. This review explores recent updates in the area of physical activity promotion and its impact on the physical and mental health consequences of childhood obesity. RECENT FINDINGS: Despite the availability of opportunities for physical activity in the school environment, namely recess and physical education classes, students do not appear to be meeting activity recommendations at school alone. Access to neighborhood parks may increase levels of physical activity and reduce time spent in sedentary behaviors at home. Less time spent watching television and in other sedentary behaviors such as playing videogames may contribute to higher rates of physical activity. Frequency of physical activity also appears to be related to improved mental health status, although the direction of this relationship warrants further exploration. SUMMARY: Physical activity is an evidence-based intervention that offers benefits to both physical and mental health. Pediatric health care providers are encouraged to engage in discussions with patients and families on the topic of physical activity and to assist them in finding ways to incorporate activity into daily life.     

Associations between physical activity and physical fitness in American children

Associations between two measures of physical fitness, 1.6-km run/walk performance and sum of three skinfold thicknesses, and selected physical activity factors were studied in a nationally representative sample of third- and fourth-grade students (1150 boys, 1202 girls). Twenty physical activity variables measured via parent and teacher questionnaires were factor analyzed, and for each of the resultant eight factors, individual factor scores were generated. These were used in two multiple regression analyses in which 1.6-km run/walk time and sum of skinfold measurements were the dependent variables. Multiple R2 for these two analyses were .21 and .18. Significant factors in both analyses were global ratings of the child's activity level, age, vigorous community activities, and gender. The results indicate that physical activity and physical fitness are significantly, although moderately, associated in young children and suggest that interventions directed toward enhancement of physical activity in children are worthy of investigation.     

Family variables and physical activity in preschool children

Correlates of the physical activity habits of preschool children were studied in a multiethnic sample. Physical activity levels of 33 low-income children were observed systematically during free-play periods at preschool. Children spent 58% of free-play time in sedentary activities (e.g., sitting), and were vigorously active only 11% of the time. Independent variables studied were child body mass index (BMI), teacher-rated Type A behavior, and parent-reported mother BMI, father BMI, parent vigorous activity, and family cardiovascular disease (CVD) risk. The multiple regression of moderate-intensity activity was significant, with family CVD risk, parent vigorous activity, and father BMI accounting for significant amounts of variance. The results suggest that the effects of parental role modeling on child physical activity levels may extend to free-play settings far beyond the confines of the home environment.     

Children's physical activity and psychological health: the relevance of intensity

Aim: To examine the relevance of physical activity intensity when assessing the relationship between activity and psychological health in 9–10-year-old children.
Methods: Activity was assessed by accelerometry in 57 boys (n = 23) and girls (n = 34). Total activity and time spent in very light (≤1.9 METs) through to vigorous activity (≥6 METs) were recorded. Psychological health inventories to assess anxiety, depression and aspects of self-worth were completed.
Results: Time accumulated in very light activity had positive correlations with anxiety and depression (r > 0.30, p < 0.05) and negative correlations with aspects of physical self-worth (r > −0.29, p < 0.05). Time accumulated in vigorous activity had negative correlations with anxiety and behavioural conduct (r > −0.30, p < 0.05) and positive correlation with aspects of physical self-worth (r > 0.28, p < 0.05). Children spending over 4 h in very light intensity activity had more negative psychological profiles than children spending under 4 h at this intensity.
Conclusion: Aspects of psychological health were negatively correlated with very light intensity activity and positively correlated with vigorous intensity activity. Further research should investigate whether reducing time spent in very light intensity activity and increasing time spent in vigorous intensity activity improves psychological health in children.     

The relationship between autonomic nervous activity and physical activity in children

BACKGROUND: There have been few studies that have reported on heart rate variability and the development of autonomic nervous function in children. This study investigated the relationship between heart rate variabilities at night and physical activity in children. METHODS: The study subjects were 29 children, including 17 boys and 12 girls. The daily activity product and heart rate variabilities during sleep at night (00.00-05.00 hours) were measured and several aspects of these parameters were analyzed. In one child (an 8-year-old girl), heart rate variability and the physical activity product were measured for 12 days. RESULTS: There was a negative correlation between the mean R-R interval and the duration (min) of heavy exercise per day (r = -0.39, P < 0.05). In the 8-year-old girl, from whom data was obtained for 12 days, the duration of heavy exercise per day was negatively correlated with the mean R-R interval (r = -0.63, P < 0.05), the number of changes in successive R-R intervals greater than 50 msec (RR50) (r = -0.74, P < 0.01), and the high frequency (HF) component (r = -0.66, P < 0.05). Furthermore, the daily number of steps was negatively correlated with the mean R-R interval (r = -0.66, P < 0.05), RR50 (r = -0.71, P < 0.05) and the HF component (r = -0.66, P < 0.05). There was a negative correlation between the amounts of energy consumption and the mean R-R interval (r = -0.69, P < 0.05). There was a negative correlation between the amounts of energy consumption and RR50 (r = -0.76, P < 0.01). Moreover, there was also a negative correlation between the amount of energy consumption and the HF component (r = -0.71, P < 0.05). CONCLUSION: These findings suggested that physical activities increase heart rate during sleep, but reduce parasympathetic nervous activity at night. Because both the HF component and RR50 reduce with growth, the exercise-related inhibition of parasympathetic nervous activity may be a developmental stimulus to reach a balanced autonomic nervous pattern in adults.     

Psychosocial correlates of physical activity in healthy children

BACKGROUND: Understanding the determinants of physical activity in children is critical for the treatment and prevention of childhood obesity. Social-cognitive theory has been used to understand behavioral patterns in children. OBJECTIVES: To explore the relationship between health beliefs, self-efficacy, social support, and sedentary activities and physical activity levels in children and to examine the relationship between physical activity and children's self-esteem. METHODS: Ninety-two children aged 10 to 16 years completed the study. Physical activity was monitored for 1 week with a motion detector (Actitrac; IM Systems, Baltimore, Md). Moderate-level activity and high-level activity were defined based on the results of treadmill testing. Health beliefs, self-efficacy, social influences, and time spent in sedentary behaviors were determined through questionnaires. Self-esteem was measured using the Piers-Harris Children's Self-Concept Scale. Chronic anxiety was measured with the Revised Children's Manifest Anxiety Scale. RESULTS: There was a significant decline in physical activity levels between ages 10 and 16 years, particularly in girls. Preteen girls spent approximately 35% more time in low- and high-level activity than did teenage girls (P<.001). Overall, children spent 75.5% of the day inactive, with a mean +/- SD of 5.2 +/- 1.8 hours watching television, sitting at the computer, and doing homework. In contrast, only 1.4% of the day (12.6 +/- 12.2 minutes) was spent in vigorous activity. Time spent in sedentary behaviors was inversely correlated with the amount of moderate-level activity (P<.001) but not high-level activity. In contrast, time spent in high-level activity correlated with self-efficacy scores (P<.001) and social influences scores (P<.005). High-level physical activity was also associated with improved self-esteem (P<.05). Higher health beliefs scores were not correlated with physical activity levels. CONCLUSIONS: Children and adolescents are largely sedentary. Correlates of high- and low-level physical activity are different. Time spent on sedentary activities is inversely correlated with moderate-level activity, while self-efficacy and social influences are positively correlated with more intense physical activity. In addition, increased high-level physical activity is an important component in the development of self-esteem in children.     

Exercise and physical activity in children with cystic fibrosis

Regular exercise and habitual physical activity are important for patients with cystic fibrosis (CF). Research has demonstrated the benefits of aerobic, anaerobic, and strength exercise training programs for health and quality of life, however, the CF patient is faced with unique barriers and challenges to participation. Recently, increased levels of habitual physical activity have been shown to slow the decline in lung function in patients with CF, and regular participation in a variety of activities may result in greater adherence in the long term. Research is now available to justify the incorporation of exercise into the routine care of patients with CF. This paper provides the background and rationale for the implementation of exercise and habitual physical activity recommendations by the health care team. Education of health care providers regarding the importance of exercise and habitual physical activity for patients with CF is needed in order for exercise and physical activity to be incorporated as key components of clinical practice and into the lives of patients with CF.     

Predicting physical activity intention and behavior in school-age children

Two studies were conducted to predict physical activity in school-aged children. Study 1 tested the utility of an integrated model in predicting physical activity (PA) intention and behavior-the theory of planned behavior (TPB) and self-efficacy theory. Six hundred and forty-five New Zealand children (aged 11-13 years) completed measures corresponding to the integrated model and a self-reported measure of PA one week later. Perceived behavioral control (PBC) and subjective norm were the two strongest predictors of intentions. Task efficacy and barrier efficacy were the two strongest predictors of PA. A second study (Study 2) was conducted to determine whether the self-efficacy measures could discriminate objectively measured PA levels. Sixty-seven Canadian children (aged 11-13 years) completed task and barrier self-efficacy measures. The following week, children classified as 'high' (n = 11) and 'lower' (n = 7) for both task and barrier efficacy wore an Actical(R) monitor for seven consecutive days to provide activity-related energy expenditure (AEE) data. Results showed that children with high efficacy expended significantly greater AEE than their lower efficacious counterparts. Findings from these two studies provide support for the use of self-efficacy interventions as a potentially useful means of increasing PA levels among school-aged children.     

Tracking physical activity and sedentary behavior in young children

Tracking of total physical activity (PA), moderate to vigorous activity (MVPA), and sedentary behavior was assessed in 42 young children (mean age at baseline 3.8 years) over a 2-year period using the Actigraph accelerometer. Tracking was analyzed using Spearman rank correlations, percentage agreements, and kappa statistics. Spearman rank correlations were r = .35 (p = .002) for total PA, r = .37 (p = .002) for MVPA, and r = .35 (p = .002) for sedentary behavior. Percentage agreements for PA, MVPA, and sedentary behavior were 38, 41, and 26 respectively. Kappa statistics for PA, MVPA, and sedentary behavior ranged from poor to fair. Results suggest low levels of tracking of total physical activity, MVPA, and sedentary behavior in young Scottish children over a 2-year period.     

Role of physical activity on health in children and adolescents

This past century has been characterized by enormous advances in almost all aspects of human achievement. A person born at the beginning of the 20th century and still alive has witnessed more technical evolution than occurred during the preceding millions of years of the Homo family. Previously we were adapted to a life‐style as hunters‐gatherers. Now, after a short spell in an agrarian culture, we have in some “privileged” societies ended up in an urbanized, highly technologic society dominated by a sedentary life‐style. Previously when a child had matured enough to understand the message of a teacher, education began, and boys learned from a “retired” hunter. Today, there is an emphasis on chronological age more or less irrespective of maturity, body dimensions, functioning or intellectual potential. “Vertical” contact with the older generation has now more or less been replaced by a “horizontal” one of individuals of the same age. Furthermore, the educational, physical, physiological and social situation of a young individual has changed dramatically within a few decades from a life‐style of activity to one more reminiscent of Homo Sedentarius. The consequences of this enormous uncontrolled trial with whole generations of young people are still to manifest themselves. This paper is a commentary from a physiological‐medical perspective.     

Factors associated with physical activity in preschool children

OBJECTIVE: Our purpose was to identify factors associated with the physical activity in young children. STUDY DESIGN: Participants were 214 children (aged 3-5 years) enrolled in 10 childcare centers who were monitored for physical activity with an accelerometer during 2 continuous days (48 hours). Mean daily activity counts, activity counts between 9 AM and 5 PM, and percentage of time spent in vigorous activity were determined. The factors investigated were age, childcare center, season, sex, body mass index (BMI), history of preterm birth, participation in organized activities, parental BMI, and parental educational level. Regression analyses were used to identify factors associated with each of the activity measures. RESULTS: A statistical model including sex, history of preterm birth, childcare center, and father's BMI accounted for 22%, 37%, and 23% of the variance in total daily counts, counts between 9 AM and 5 PM, and percentage of time spent in daily vigorous activity, respectively. Childcare center was the highest individual predictor of activity. Boys were more active than girls in all activity measures except counts between 9 AM and 5 PM. Children born preterm were less active than children born at term, and high activity levels in the child were associated with a low BMI in fathers. CONCLUSION: The findings indicate that sex, history of preterm birth, childcare center, and father's BMI influence the daily physical activity of young children.