Kyles, C. and Lounsbery, M. (2004). Project destiny: Initiating physical activity for nonathletic girls through sport. Journal of Physical Education, Recreation and Dance, 75(1), 37-41.

Fifteen females ranging in age from 11 to 14 years took part in a five-week summer programme named ‘Project Destiny’, which was designed for non-athletic preteen girls. The two goals of the programme were: 1) to use fun and authentic learning experiences to introduce the benefits of PA and sport and encourage a healthy lifestyle during adolescence; 2) to spark girls’ interest in PA and sport participation. Two staff members implemented the programme. It was determined that this all-girls environment provided fewer distractions and a greater opportunity to raise self-esteem and confidence. The curriculum consisted of athletic activities, health and wellness workshops, fine arts projects, leadership exercises, cooperative games, and guest speakers. The programme took place at a local park, three days per week, from 9:30 am to 4:30 pm. Competition during sport activities was not encouraged until a girl requested a game. At the midpoint of the programme, participants became more interested in competition and had increased enthusiasm, effort, and participation during sports clinics. When surveyed, all girls described the programme as fun and said they were more interested in sports participation and would participate in ‘Project Destiny’ next year. Participants acknowledged that the all-girls environment provided a safe and nurturing atmosphere.

Collaborating with classroom teachers to increase daily physical activity: The GEAR Program

Maeda, J.K. and Murata, N.M. (2004). Collaborating with classroom teachers to increase daily physical activity: The GEAR Program. Journal of Physical Education, Recreation and Dance, 75(5), 42-46.

Little time is allowed for physical education during the school day as schools turn their attention to core academic subjects. GEAR (Getting Energized and Recharged) activities provide for short bouts of physical activity for children to supplement for the lack of physical education classes. Activities range from walking to taped aerobic routines designed for children. Twenty-four preschool through second grade teachers at three elementary schools in Hawaii used the GEAR activities a minimum of five minutes, once a week. The suggested activities took little time and were easy to implement, so as to appeal to the teachers who need to focus on core academics and not waste time during the school day. The teachers were positive about the activities saying that they allowed the students time to refocus on their lessons, the students enjoyed the activities and that they would continue to use activities in their classrooms the following school year.

Televison viewing, physical activity and obesity

Energy expended playing video console games: An opportunity to increase children's physical activity?

Maddison, R., Mhurchu, C.N., Jull, A., Jiang, Y., Pravessis, H. and Rodgers, A. (2007) Energy expended playing video console games: An opportunity to increase children's physical activity? Pediatric Exercise Science. 19:334-343

The aim of this study was to examine the energy expenditure and activity levels associated with playing home game consoles and new generation of interactive video games to determine if these games have the potential to increase physical activity levels in children. Twenty-one children (11 boys and 10 girls) aged between 10 and 14 years participated in this study. The children were fitted with a heart rate monitor and accelerometer. Oxygen uptake was measured using a portable indirect calorimetry gas-exchange system. Each subject was measured at several time points during resting, inactive video game and playing the interactive electronic games which included boxing, baseball and dancing. The children played the games for 5 minute intervals. Energy expenditure was significantly greater during the interactive video games when compared to the inactive games and with rest. The boxing game induced the highest energy expenditure followed closely by the baseball game. Significantly greater heart rates were recorded during the interactive games compared to resting and inactive games. Energy expended whilst playing the interactive games was similar to other light to moderate intensity activities. The present data suggests that substituting periods of inactivity (non-active video games) with sustained interactive video game play (e.g. 30 min per day) could have a measurable impact on body weight. However, despite the potential for video games to help increase children's physical activity levels sustainability of this activity needs to be determined. This study only measured energy expenditure for short 5 minute bouts of activity. Therefore further research is needed to assess whether children would play these games frequently and for long enough to have a measurable impact on their health and fitness.

Efects of open-loop feedback on physical activity and television viewing in overweight and obese children

Goldfield, G. S., Mallory, R., Parker, T., Cunningham, T., Legg, C., Lumb, A., Parker, K., Prud’homme, D., Gaboury, I. and Adambo, K. B. (2006).  Effects of open-loop feedback on physical activity and television viewing in overweight and obese children: a randomized, controlled trial. Pediatrics, 118, 157-166.

This study evaluated the effects of open-loop feedback plus reinforcement versus open-loop feedback alone on physical activity, targeted sedentary behaviour, body composition, and energy intake in youth. Thirty overweight children ages 8 to 12 years were randomly assigned to one of two groups; (1) a control group who were encouraged to exercise without television limitations and (2) an intervention group who earned television viewing time by exercising.  Participants in the intervention group earned one hour of television watching for every 1 hour of moderate intensity physical activity they took part in.  This was controlled by an electronic token machine installed on the television. The study found that children increased their physical activity, reduced snacking and cut down on TV viewing when parents made TV and video games a reward for exercise. For example, participants in the intervention group increased physical activity by 65 percent during the eight-week study period, compared with a 16 percent increase among participants in the control group. In addition, intervention group members reduced daily TV watching from three hours to 45 minutes, while control participants increased their viewing by 15 minutes. Furthermore, children who watched less television also reduced snacking and lowered their overall caloric intake. Researchers suggest that these findings support the notion that excessive TV viewing encourages snacking and weight gain.

Wathing television is associated with childhood obesity: but is it clinically important

Hancox, R.J. & Poultn, R. (2005). Watching television is associated with childhood obesity: but is it clinically important? International Journal of Obesity (in press).

This study examined the impact of television viewing during childhood and adolescence on body mass index (BMI) in children up to the age of 15 years. In total, 976 individuals were assessed at birth and every 2 years from the age of 3 to 15 years old. Between the ages of 5 and 11 years old parents were asked to estimate how much television their children watched and between 13 and 15 years of age the children themselves were asked to self report. Results indicated that at each age, BMI and overweight were significantly associated with the amount of television watched. Between the ages of five and 15, children were found to watch an average of 2.33 hours of television per weeknight. Aged 13 to 15 they watched an average of 24.6 per week (including weekends). At each age, the mean hours television viewing reported up to and including that age was significantly associated with BMI. These associations were stronger in girls, which was thought to be a result of lifestyle differences and physical make up. The researchers noted that although the effect size appears small, the association between television viewing and BMI is stronger than that reported for BMI, diet and physical activity.

Physical activity participation and the environment

Variation in physical activity lies with the child, not his environment: evidence for an 'activitystat' in young chidren

Wilkin, T. J., Mallam, K. M., Metcalf, B. S., Jeffery, A. N. & Voss, L. D. (2006). Variation in physical activity lies with the child, not his environment: evidence for an 'activitystat' in young children (EarlyBird 16). International Journal of Obesity, 30(7): 1050-1055.

The findings of this study imply that children's physical activity is not determined by the environment but by some internal regulator that all children share. While children vary in how active they are, they are consistent in the amount of physical activity they engage in every day, regardless of the amount of school-based physical education they receive, their daily routine, background or culture. The researchers, from the Peninsula Medical School in Plymouth, studied the physical activity of children aged 5 to 10 in a variety of schools. The team compared several different situations: Group 1, which included 307 children from 53 primary schools around Plymouth who were tested at ages 5 and 6. Group 2 included 215 children ranging in age from 7 to 11 years, selected from three schools around Plymouth representing high income areas and areas of lower socioeconomic status. Group 3 included 732 children attending school in Glasgow. The three schools in Group 2 included a private preparatory school with 9 hours per week of physical education; a village school with 2.2 hours per week of physical education, and an inner city school that had physical education only 1.8 hours per week. Each subject wore a matchbox-size accelerometer for 7 days. The device recorded the time along with duration and intensity of activity, which was then downloaded into a computer at the end of the week. The researchers found that total levels of physical activity were the same on week days and weekend days. Similar findings were obtained when comparing children who walked to school with those transported by car, or when they looked at children in the Glasgow school system versus those in Plymouth. Moreover, total physical activity scores were independent of the amount of time spent sleeping or watching TV or playing video games.

Social–psychological and physical environmental factors in groups differing by levels of physical activity: A stdy of Scottish adolescent girls

Whitehead, S. H., Biddle, S. J. H., O'Donovan, T. M. & Nevill, M. E. (2006). Social–psychological and physical environmental factors in groups differing by levels of physical activity: A study of Scottish adolescent girls. Pediatric Exercise Science, 18(2): 226-239.

Scottish data shows that girls’ participation in sports more than twice a
week declines from 76% in the 8- to 11-year age group to 67% in the 12- to 15-year age group (10% lower than boys) and that the Government recommendation of 60 minutes of physical activity of at least moderate intensity on most days of the week is being met by 66% of girls at ages 10 to 11, but only 36% of girls at ages 14 to 15 years. This study aimed to address the factors influencing Scottish adolescent girls’ participation in physical activity (PA). The participants were 352 girls aged 11 to 16 years, who completed surveys measuring PA participation and potential social-psychological and physical-environmental correlates. Data were analysed separately by two age groups (11-13 and 14-16 years). The results revealed that in the younger age group, mother’s participation, perceived importance, and home equipment use were higher among those with higher  PA levels. In the older age group, perceived importance, home equipment use, neighbourhood perceptions, and the use of and enjoyment of local facilities were higher among girls with higher PA levels. The authors suggest that older girls place less importance on significant others and move more toward autonomy away from the home.

Peronal, family, social, and environmental correlates of active commuting to school

Timperio, A., Ball, K., Salmon, J., Roberts, R., Giles-Corti, B., Simmons, D., Baur, L. A. & Crawford, D. (2006). Personal, family, social, and environmental correlates of active commuting to school. American Journal of Preventive Medicine, 30(1): 45-51.

Active commuting to school can be an important opportunity for children to accumulate adequate physical activity for improved cardiovascular risk factors, enhanced bone health, and psychosocial well-being. The purpose of this cross-sectional study was to examine personal, family, social, and environmental correlates of active commuting to school among children. The study population was 235 children aged 5 to 6 years and 677 children aged 10 to 12 years from 19 elementary schools in Melbourne, Australia. Self-administered questionnaires were completed by parents, and the older children. The shortest possible routes to school were examined using a geographic information system (GIS). In both age groups, negative correlates of active commuting to school included parental perception of few other children in the neighbourhood, no lights or crossings for their child to use, and having to cross a busy road en route to school. In younger children, an objectively assessed steep incline en route to school was negatively associated with walking or cycling to school. The existence of a direct car  route was negatively associated with walking or cycling to school among older children. Among both age groups, children were more likely to actively commute to school if their route was under 800 meters. There were no associations with perceived energy levels or enjoyment of physical activity, weight status, or family factors found from this study. The authors conclude that creating child-friendly communities and providing skills to safely negotiate the environment may be important. Environmental correlates of active transport in children and adults may differ and warrant further investigation.

Chldren of parents concerned about road safety are more likely to be overweight or obese

Timperio, A., Salmon, J., Telford, A. and Crawford, D.  (2005).  Perceptions of local neighbourhood environments and their relationship to childhood overweight and obesity. International Journal of Obesity,  29(2), 170-175.

In this cross sectional study that measured the perceptions of the local neighbourhood according to the parents of over 1000 children, it was found that among 10-12 year old children, those whose parents agreed that there was heavy traffic in their local streets were more likely to be overweight or obese. This suggests that among this age group parental perceptions of heavy traffic on local streets and concern about road safety may be indirect influences on overweight and obesity.

Unafe to play? Neighbourhood disorder and lack of safety predict reduced physical activity among urban children and adolescents

Molnar, B.E., Gortmaker, S.L., Bull, F.C., and Buka, S.L. (2004). Unsafe to play? Neighbourhood disorder and lack of safety predict reduced physical activity among urban children and adolescents. American Journal of Health Promotion, 18(5), 378-386.

Baseline data from 1378 urban youth (ages 11.5 to 15.5 years) and their caregivers were analysed with observational data from 80 neighbourhood communities, to determine the relationship between neighbourhood safety, physical disorder and social disorder and levels of physical activity. Data came from the Project on Human Development in Chicago Neighbourhoods (PHDCN), a multidisciplinary, longitudinal study of youth, families and neighbourhoods, conducted from 1995 through 2001. Measures included: parental estimates of time spent by youth in recreational programming; residents' assessment of neighbourhood safety and videotaped observations of neighbourhood communities. Results illustrate that family-level and neighbourhood-level socio-economic factors were positively associated with physical activity. Sixty-one percent of youth were reported as not participating in any recreational physical activity per week. Neighbourhood social disorder and community members' assessment of the neighbourhood as unsafe to play were significantly and inversely associated with youth physical activity.

Barriers to and correlates of physical activity particpation

Sef-perceived barriers to activity participation among sedentary adolescent girls

Kimm, S. Y. S., Glynn, N. W., McMahon, R. P., Voorhees, C. C., Striegel-Moore, R. H. and Daniels, S. R. (2006). Self-perceived barriers to activity participation among sedentary adolescent girls.  Medicine and Science in Sports and Exercise, 38(3), 534-540.

This study looks at the potential barriers to participation in physical activity amongst adolescent girls. Girls enrolled in the in the National Heart and Lung Blood Institute Growth and Health Study since the ages of 9 or 10 were studied.  Of the 2379 black and white girls enrolled in the study those who reported their weekly activity frequency as ‘‘sometimes’’ or ‘‘rarely’’ were included and surveyed for three consecutive years from the ages of 16 or 17 years. Barriers to activity were assessed using a 10-item questionnaire.  Responses were cross-examined with other reported information.  Race-specific longitudinal regression examined the impact of barrier scores on activity levels and also potential factors having an impact on barrier scores. More than half of the girls surveyed from the ages of 16 or 17 to 18 or 19 were identified as being sedentary. Of those girls who were classified as sedentary, the majority (65 percent for black girls and 80 percent for white girls) perceived a lack of time as their primary barrier to activity. They also frequently reported feeling too tired or uninterested in participating in physical activities. Other commonly reported barriers included safety and body image concerns. The survey found that sedentary habits are mostly linked to internal barriers, for example, interest and motivation, which were unrelated to external factors such as their job and recreation. Other findings from the study found that habitual physical activity was significantly lower amongst black girls and these girls spent twice as much time watching television or videos and were significantly heavier than white girls. More white girls reported lack of time, and also were significantly more likely to indicate fatigue and self-consciousness as a barrier to exercise. Black girls were more than twice as likely to cite safety as a concern, although this was not one of the leading barriers to activity participation. Overall, black girls cited fewer barriers than white girls. The researchers suggest that the identification of barriers to participation in physical activity during adolescence has an important public health implication in combating the emerging pandemic of obesity among young people in the U.S.

Corelates of participation in physical activity for adolescent girls: a systematic review of recent literature

Biddle, S. J. H., Whitehead, S. H., O’Donovan, T. M. & Nevill, M. E. (2005). Correlates of participation in physical activity for adolescent girls: a systematic review of recent literature. Journal of Physical Activity and Health, 2(4), 423-434.

This review examined the correlates of participation in physical activity (PA) in adolescent girls. PA levels are generally low in this population group, and the aim of the research was to discover the determinants of physical activity, in order that interventions to increase activity levels can be effectively tailored to this age group. Fifty papers, published between 1999 and mid-2003, that reported a measure of physical activity and at least one potential correlate of physical activity in adolescent girls were analysed. The results showed that the demographics of female gender, non-white ethnicity and age had a negative effect on physical activity levels, while higher socio-economic status had a positive effect. Psychological correlates positively associated with physical activity were enjoyment, perceived competence, self-efficacy and physical self-perceptions. Behavioural correlates showed that smoking was associated with lower physical activity levels and involvement in organised sport was associated with greater activity levels. Physical activity was also associated with parental and family support. The results indicate that the most effective ways of improving physical activity levels in adolescent girls would be through interventions that promote positive psychology, organised sport and family support.

Adoescent patterns of physical activity.  Differences by gender, day and time of day

Jago, R., Anderson, C. B., Baranowski, T. and Watson, K.  (2005).  Adolescent patterns of physical activity.  Differences by gender, day and time of day.  American Journal of Preventive Medicine, 28(5), 447-452.

With an aim of gathering more information about physical activity habits of adolescents, this study used an objective measurement to investigate the differences in activity patterns related to gender, body mass index, day and time of day. The study looked at 81 eighth grade adolescents who all wore an accelerometer for 4 days and who all additionally kept a previous-day physical activity recall diary.  Minutes per hour spent in sedentary, light and moderate/vigorous activity were calculated for three time periods on each day.  Results indicated significant gender by day by time differences in sedentary, and moderate/vigorous activity, although there were no significant BMI interactions.  Except on Sundays, boys were less sedentary and more active than girls during the late afternoon period.  Boys spent more time engaged in TV/electronics and sports, while girls spent more time in personal care. In conclusion consistent gender differences were found in activity levels, especially for the late afternoon period.  Significant increases in sitting , TV, electronic games and chores were seen for weekend days.  Furthermore the results support strategies to reduce sitting and electronic recreation, which may increase physical activity levels.

Obesity among children and adolescents

CONSENSUS STATEMENT: Childhood Obesity

Speiser, P. W., Rudolf, M. C. J., Anhalt, H., Camacho-Hubner, c., Chiarelli, F., Eliakim, A., Freemark, M., Gruters, A., Hershkovitz, E., Iughetti, L., Krude, H., Latzer, Y., Lustig, R. H., Pescovitz, O. H., Pinhas-Hamiel, O., Rogol, A. D., Shalitin, S., Sultan, C., Stein, D., Vardi, P., Werther, G. A., Zadik, Z., Zuckerman-Levin, N. & Hochberg, Z. (2005). CONSENSUS STATEMENT: Childhood Obesity. Journal of Clinical Endocrinology & Metabolism, 90(3), 1871-1887.

This article outlines a consensus statement on childhood obesity that was agreed by a group of 65 international health professionals at a conference in 2004. In developing the consensus statement, the group examined the available evidence relating to the problem of childhood obesity and developed recommendations for future action. The article presents research evidence on the prevalence, diagnosis and causes of obesity in young people, and discusses the risks of children developing medical conditions as a result of obesity, such as diabetes, the metabolic syndrome, hyperandrogenemia, cardiovascular disease and respiratory problems. Guidance and recommendations for the prevention of obesity through a multitude of settings and life stages, such as schools, communities, during pregnancy and through government policies are summarised. Suggested ways of treating the problem through dietary, lifestyle, exercise and pharmacological intervention are also discussed.

Physical activity considerations for the treatment and prevention of obesity

Jakicic, J. M. & Otto, A. D. (2005). Physical activity considerations for the treatment and prevention of obesity. American Journal Of Clinical Nutrition, 82(1), Supplement, S226-S229.

This paper outlines the issues surrounding research on physical activity in the treatment and prevention of obesity; such as the role of physical activity in weight loss and in the prevention of weight gain, whether health benefits for overweight adults can be achieved independent of weight gain; and the most effective dose of physical activity in weight control. Physical activity is the most variable component of energy expenditure and therefore has been the target of behavioural interventions to modify body weight.

Key findings:

 - Physical activity is an important component on long-term weight control. Adequate levels of activity should be prescribed to combat the obesity epidemic.
 - 30 min/d of moderate-intensity physical activity may improve health outcomes but the amount of physical activity that may be necessary to control body weight may be >30 min/d.
 - At least 60 min of moderate-intensity physical activity may be necessary to maximize weight loss and prevent significant weight regain.
 - Physical activity is important in the prevention of weight gain and the development of obesity.
 - Physical activity has an independent effect on health-related outcomes when compared with body weight, suggesting that adequate levels of activity may counteract the negative influence of body weight on health outcomes.

The paper concludes that it is important to target intervention strategies to facilitate the adoption and maintenance of an adequate amount of physical activity to control body weight.

Interventions for preventing obesity in children

Summerbell C. D, et al. (2005). Interventions for preventing obesity in children. The Cochrane Database of Systematic Reviews, Issue 3.

A study published in the Cochrane Database of Systematic Reviews, a publication of the United Kingdom-based health information and research group Cochrane Collaborative, found that obesity interventions that incorporate ‘fun’ physical activities and food preparation lessons are more effective than standard programmes in helping overweight children lose weight. Researchers conducted a meta-analysis of 22 international studies that tested the efficacy of physical activity and nutrition education programmes. They found that although most children who took part in short-term (12 weeks to 12 months) or long-term (at least 12 months) exercise and nutrition interventions did not lose a significant amount of weight, ‘nearly all’ of the studies found that children's physical activity levels or eating habits improved after participating in an intervention programme. The most effective interventions included ‘fun’ events, such as dance or martial arts classes, and presented healthy foods in a creative way. Study authors conclude that programmes that integrate enjoyable activities into exercise and nutrition programmes and also focus on creating a supportive ‘psycho-social’ environment are likely to be most effective in helping overweight children lose weight.

Relations of moderate and vigorous physical activity to fitness and fatness in adolescents

Gutin, B., Yin, Z., Humphries, M. C. and Barbeau, P.  (2005).  Relations of moderate and vigorous physical activity to fitness and fatness in adolescents.  American Journal of Clinical Nutrition, 81(4), 746-750.

This paper looks at the hypothesis that vigorous physical activity would be associated with better cardiovascular fitness and lower body fat to a greater degree than moderate intensity physical activity.  It is a cross sectional study of 421 black and white high school students and physical activity was measured over 5 days using accelerometry.  Cardiovascular fitness was assessed using a multistage fitness test and body fat measured with dual-energy x-ray absorbtiometry. The results indicated that a higher index for cardiovascular fitness  was associated with higher amounts of moderate and vigorous physical activity.  More variance was explained by vigorous than by moderate physical activity.  A lower percentage of body fat was associated with higher amounts of vigorous physical activity but not with the moderate levels of physical activity.  In conclusion the study found that adolescents who engaged in relatively large amounts of free-living vigorous exercise were likely to be relatively fit and lean.

Exercise prescription for the prevention of obesity in adolescents

Carrel, A. L. and Bernhardt, D. T. (2004).  Exercise prescription for the prevention of obesity in adolescents. Current Sports Medicine Reports, 3(6), 330-336.

Childhood obesity is an increasing public health problem which poses important challenges for both health care and school-centred environments.  Each faces difficulties in successfully addressing this major problem.  Schools report that they have a lack of training in intervention, and health care providers report ineffective office-based intervention strategies. The prevention and treatment of childhood obesity could be improved if the coordination of interventions in both the school and office is improved. Prescribing exercise to prevent a further rise in childhood obesity could be very effective.  The review evaluates recent literature relating to the health care provider’s role in prescribing exercise and the associated health benefits of exercise for children.  Health professionals caring for children and adolescents are in a key position to help prevent and treat obesity by promoting behavioural and environmental changes.  The evidence base is insufficient to provide specific guidelines for assessment and treatment of all aspects of childhood and adolescent obesity.  The paper includes a number of recommendations which reflect critical reviews of the literature and are based upon expert committee guidelines.

Physical activity to prevent obesity in young children: cluster randomised controlled trial.

Reilly, J.J., Kelly, L., Montgomery, C., Williamson, A., Fisher, A., McColl, J.H., Lo Conte, R., Paton, J.Y., and Grant, S. (2006) Physical activity to prevent obesity in young children: cluster randomised controlled trial. British Medical Journal 333 (7577)

The aim of this study was to examine the effects of a physical activity intervention on reducing the body mass index (BMI) of nursery school children. The participants were 545 children who attended one of the 36 randomly selected Glasgow nurseries. Each nursery was randomly allocated to either the intervention or control group. The 6 month intervention consisted of a nursery and home based element. The nursery element involved children in the intervention group participating in three 30 minute sessions of PA each week. Families were given resource packs which gave information on how to link PA at nursery and at home. The control group continued with their normal lessons and did not increase PA during the intervention period. BMI was measured at baseline, 6 and 12 months after the start of the intervention. Accelerometers were used to measure PA and sedentary behaviours over a 6 day period at baseline and at 6 months. Movement skills were measured at baseline and at 6 months using a movement assessment battery. There was no significant difference found in BMI measurements, physical activity and sedentary behaviours between the intervention and control group. Children in the intervention group scored higher in the movement skills tests than the control children. The intervention was not successful in reducing BMI in pre-school children, however it did significantly improve children's movements skills.

Tracking of physical activity from childhood to adulthood

Physical activity during the transition from adolescence to adulthood

Zick, C.D., Smith, K.R., Brown, B.B., Fan, J.X. and Kowaleski-Jones, L. (2007) Physical activity during the transition from adolescence to adulthood Journal of Physical Activity and Health. 4: 125-137