Bone Strengthening Activities Research Articles

Moving beyond moderate-to-vigorous physical activity: A longitudinal study on adherence to 24-hour Movement Guidelines in adolescents

ObjectivesLow adherence to 24-hour Movement Guidelines for moderate-to-vigorous physical activity, screen time and sleep during adolescence is well documented, yet recommendations regarding light physical activity, vigorous physical activity and muscle and bone strengthening activities have received less attention. This study comprehensively examined adherence to seven components of the movement guidelines in adolescents and analysed disparities by age and gender. DesignLongitudinal study with two assessment time points, separated by one year. MethodsData were collected in 216 New Zealand adolescents aged 12–17 years, and at 1-year follow-up in 167 participants (77 %), using thigh-worn accelerometers and a self-reported diary. ResultsAdherence rates were 3.7 % for moderate-to-vigorous physical activity, 13.0 % for screen time, 44.0 % for sleep, 14.4 % for light physical activity, 36.1 % for vigorous physical activity, 30.6 % for bone and muscle strengthening activities, and 4.6 % for consistent bedtimes. Less than 1 % of participants met all seven recommendations. Adherence was disproportionately low amongst older adolescents for light physical activity, screen time and consistent bedtimes, and amongst girls for vigorous physical activity and muscle and bone strengthening activities. Over one year, adherence declined for light physical activity (15.0 %–7.2 %) and screen time (15.6 %–6.0 %). ConclusionsNew Zealand adolescents are not adhering to recommendations for a healthy balance of time use outlined in the 24-h Movement Guidelines. These findings highlight the need for adolescents to increase their daily movement, with a particular focus on light physical activity amongst older adolescents and muscle and bone strengthening activities amongst girls.

Exercise in the management of polycystic ovary syndrome: A position statement from Exercise and Sports Science Australia

Polycystic ovary syndrome (PCOS) is the most prevalent endocrine condition amongst females of reproductive age, leading to lifelong cardiometabolic, reproductive, psychological, and dermatologic symptoms as well as a reduced quality of life. Lifestyle interventions, which can include structured exercise programmes delivered by appropriately trained exercise professionals such as clinical exercise physiologists, are considered first-line strategies in PCOS management due to their therapeutic effects on various health outcomes and quality of life. This position statement builds on the 2023 International Evidence-based Guideline for the Assessment and Management of PCOS and describes the role of the exercise professional in the context of the multidisciplinary care team which includes physicians and allied health professionals. This position statement aims to equip exercise professionals with a broad understanding of the pathophysiology of PCOS, how it is diagnosed and managed in clinical practice, and evidence- and consensus-based recommendations for physical activity and exercise in PCOS management. In line with the physical activity recommendations for the general public, individuals with PCOS should aim to undertake between 150 to 300min of moderate-intensity or 75 to 150min of vigorous-intensity aerobic activity per week, or an equivalent combination of both spread throughout the week. Additionally, muscle-strengthening activities on two non-consecutive days per week are recommended to maintain health and prevent weight gain. For further health benefits and to achieve modest weight loss, individuals with PCOS should aim for a minimum of 250min of moderate-intensity or 150min of vigorous-intensity aerobic activity per week, or an equivalent combination of both spread throughout the week, plus muscle-strengthening activities on two non-consecutive days per week. Adolescents with PCOS should aim for a minimum of 60min moderate- to vigorous-intensity activity each day, incorporating muscle- and bone-strengthening activities three times per week. Finally, exercise professionals should consider the significant psychological burden, including weight stigma, and the high prevalence of comorbidities amongst individuals with PCOS and take appropriate measures to deliver safe and efficacious exercise interventions.

Cross-sectional and longitudinal associations between the 24-hour movement behaviours, including muscle and bone strengthening activity, with bone and lean mass from childhood to adolescence

BackgroundThis study aimed to assess whether moderate-to-vigorous physical activity (MVPA), sport and exercise as a proxy measure of muscle and bone strengthening activity, sedentary behaviour, and sleep were associated with total-body-less-head (TBLH) bone mineral content (BMC) and TBLH lean mass cross-sectionally and longitudinally from age 6 to 9 years and age 9 to 11 years to age 15 to 17 years.MethodsWe used longitudinal data from a population sample of Finnish children from the Physical Activity and Nutrition in Children study (age 6 to 9 years: n = 478, 229 females; age 9 to 11 years: n = 384, 197 females; age 15 to 17 years: n = 222, 103 females). Linear regression analysed the cross-sectional and longitudinal associations between accelerometer-assessed MVPA, sedentary time and sleep, and questionnaire-assessed sport and exercise participation and screen time with dual-energy X-ray absorptiometry-assessed TBLH BMC and lean mass.ResultsIn females, MVPA at age 6 to 9 years was positively associated with TBLH BMC at age 15 to 17 years (β = 0.008, p = 0.010). Sport and exercise at age 9 to 11 years was positively associated with TBLH BMC (β = 0.020, p = 0.002) and lean mass (β = 0.343, p = 0.040) at age 15 to 17 years. MVPA at age 9 to 11 years was positively associated with TBLH lean mass (β = 0.272, p = 0.004) at age 15 to 17 years. In males, sleep at age 6 to 9 years was positively associated with TBLH lean mass (β = 0.382, p = 0.003) at age 15 to 17 years. Sport and exercise at age 9 to 11 years was positively associated with TBLH BMC (β = 0.027, p = 0.012) and lean mass (β = 0.721, p < 0.001) at age 15 to 17 years.ConclusionsPromoting engagement in the 24-hour movement behaviours in childhood, particularly sport and exercise to strengthen muscle and bone, is important in supporting bone and lean mass development in adolescence.Trial registrationNCT01803776; first trial registration date: 04/03/2013.

Physical activity, sedentary behaviour, and sleep knowledge and self-efficacy among parents of young children in Canada.

Engaging in healthy movement behaviours in early childhood is beneficial for children's development, and parents play a critical role in shaping movement habits during these formative years. This study aimed to explore parents' knowledge of the Canadian 24-Hour Movement Guidelines for the Early Years (The Guidelines) and their perceived knowledge and self-efficacy of movement behaviour concepts in early childhood. The influence of sociodemographic characteristics on these variables was also examined. Via a cross-sectional online survey with parents/guardians (n = 576) of young children in Canada, participants' knowledge of The Guidelines (11 items), and perceived knowledge (11 items; 5-point scale) and self-efficacy (11 items; 11-point scale) of movement behaviour concepts in early childhood were examined. Descriptive statistics were calculated for independent variables and multivariate regression models were estimated to examine sociodemographic factors that were associated with participants' knowledge and self-efficacy. Few participants (11.9%) reported to be familiar with The Guidelines. Parents were most knowledgeable about the screen time guideline for children under 2 years (75.0% correctly identified the guideline) and least familiar with the recommendation for toddler/preschooler total physical activity (14.7% correctly identified the guideline). Parents/guardians perceived they were the most knowledgeable about safe sleep practices (65.9% very/extremely knowledgeable) and least knowledgeable about muscle- and bone-strengthening activities (71.8% not at all/somewhat knowledgeable). Overall, parents/guardians were moderately confident in promoting healthy movement behaviours (M = 6.01; SD = 1.73). Participants with higher levels of education reported significantly higher perceived knowledge compared to those who were less educated (p = .004), and parents/guardians identifying as White reported significantly higher levels of self-efficacy compared to parents/guardians from minority ethnic groups (p = .028). Finally, parents/guardians who were more physically active reported both higher perceived knowledge (p < .001) and self-efficacy (p < .001) than those who were less active. These findings shed light on the need to raise awareness of The Guidelines among parents of young children and highlight specific movement behaviour concepts in need of focus in future training for this population. Targeted education for parents/guardians from lower socioeconomic groups is also needed to address equity concerns. The online version contains supplementary material available at 10.1186/s44167-024-00051-x.

Consensus statement on Singapore integrated 24-hour activity guide for children and adolescents

Lifestyle activities, such as regular physical activity, are important for good metabolic health and the prevention of non-communicable diseases. Epidemiological studies highlight an increase in the proportion of overweight children in Singapore. A workgroup was formed to develop recommendations to encourage children and adolescents (aged 7-17 years) to adopt a holistic approach towards integrating beneficial activities within a daily 24-hour period for good metabolic and general health. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) Evidence to Decision framework was employed to formulate the public health question, assess the evidence and draw conclusions for the guide. The evidence for international 24-hour movement guidelines, and guidelines for physical activity, sedentary behaviour, and sleep and eating habits were reviewed. An update of the literature review from August 2018 to end of September 2020 was conducted through an electronic search of Medline and Cumulative Index to Nursing and Allied Health Literature (CINAHL) databases. Ten consensus statements were developed. The statements focused on the overall aim of achieving good metabolic health through integration of these activities and initiatives: light and moderate- to vigorous-intensity physical activity on a regular basis; muscle- and bone-strengthening activities; limiting sedentary behaviour; regular and adequate sleep; good eating habits and choosing nutritionally balanced foods and drinks; practise safety in exercise; and aiming to achieve more or all aforementioned recommendations for the best results. This set of recommendations provides guidance to encourage Singapore children and adolescents to adopt health-beneficial activities within a 24-hour period.

Understanding action control of resistance training among adults

BackgroundRegular muscle and bone strengthening activities through resistance training (RT) have been associated with numerous health benefits, particularly as adults age, yet participation is low. Effective promotion is likely founded on an understanding of theory-based correlates, yet almost all RT research has focused on college-aged convenience samples and employed social cognition models, which do not consider the intention-behavior gap. The purpose of this study was to explore RT from the perspective of the multi-process action control (M-PAC) framework in a large Canadian adult sample. MethodCanadian adults (N = 1338) completed M-PAC measures of reflective (instrumental attitude, affective attitude, perceived capability and opportunity), regulatory (planning and self-monitoring), and reflexive (habit, identity) processes as well as intention to engage in RT at baseline and RT behavior two-weeks later. ResultsThree intention-behavior profiles emerged: a) non-intenders who were not active (41.4%), b) unsuccessful intenders who failed to enact their positive intentions (32.9%), and c) successful intenders who engaged in RT (23.5%). A discriminant function analysis (p < .01) showed that instrumental and affective attitude, perceived opportunity and planning/self-monitoring distinguished between all three intention-behavior profiles, while perceived capability predicted the intention-RT profiles of females but not males (p < .01). By comparison, identity was particularly important to younger/middle-aged adults than older females (p < .01), while habit was associated with the intention-RT profiles of older adults but not younger/middle-aged adults (p < .01). ConclusionsThe findings support the importance of considering both intention formation and translation in RT. Behavior change techniques aimed at reflective, regulatory, and reflexive processes appear necessary. Additional considerations of targeting specific constructs by age and sex may maximize the potential effectiveness of RT interventions.

Surveillance of Meeting the Youth Physical Activity Guideline: Impact of Including Vigorous-Intensity and Bone-Strengthening Activities

ABSTRACT Purpose: The US youth physical activity guideline recommends participation in four types of physical activity: moderate-to-vigorous intensity aerobic (MVPA), vigorous-intensity aerobic (VPA), muscle-strengthening, and bone-strengthening physical activity. Current national prevalence estimates of meeting the youth physical activity guideline are typically based on measures of the MVPA and muscle-strengthening components. This study sought to examine differences in prevalence estimates using this current approach and then including measures of all four components. Methods: Data from US high school student respondents to the 2010 National Youth Physical Activity and Nutrition Survey were analyzed (n = 10,596). Prevalence of students meeting the youth physical activity guideline were assessed and compared using 1) measures of MVPA and muscle-strengthening components only and 2) also including measures of the VPA and bone-strengthening components. Results: Overall, 15.2% students met the MVPA, 50.7% met the muscle-strengthening, 70.6% met the VPA, and 80.7% met the bone-strengthening components. In total, 12.1% (95% confidence interval: 10.9, 13.3) of students met both the MVPA and muscle-strengthening components, and 11.2% (95% confidence interval: 10.0, 12.4) met all four components. Conclusions: Incorporating additional measures of VPA and bone-strengthening activity into current surveillance systems may not meaningfully impact national estimates of meeting the youth physical activity guideline.

The important role of gymnastics in the lives of girls

This article identified the real reasons why you should enroll your daughter in gymnastics classes. The benefits of Gymnastics classes in girls life were discussed in this work. As far as I am concerned gymnastics is one way to help make that happen. I think the fact that it's largely a female sport, makes gyms an ideal place for little girls to start to learn self-confidence as they exercise their bodies. Children and adolescents between the age of 6 and 17 should get 60 minutes or more of physical activity a day. And as part of their 60 minutes of physical activity a day, they should include muscle and bone strengthening activities at least three days a week.

Sarcopenia Is Negatively Related to High Gravitational Impacts Achieved From Day-to-day Physical Activity.

BackgroundSarcopenia has been associated with reduced physical activity (PA). We aimed to determine if sarcopenia, and specific components of muscle size, function, and physical performance, are associated with high impacts achieved during habitual PA, as these are related to bone strength in community-dwelling older women.MethodsParticipants were older women from the Cohort of Skeletal Health in Bristol and Avon. We defined sarcopenia using the EWGSOP criteria. Lower limb peak muscle power and force were assessed using Jumping Mechanography (JM). High vertical impacts were assessed by tri-axial accelerometry (at least 1.5g above gravity). Cross-sectional associations were analyzed by linear regression, adjusting for age, height and weight (or fat mass for models including appendicular lean mass index), comorbidities, smoking, alcohol, and Index of Multiple Deprivation.ResultsOur analyses included 380 participants, with mean age 76.7 (SD 3.0) years; 242 (64%) also completed JM. In age-adjusted analysis, a negative relationship was observed between severity of sarcopenia and high, but not medium or low, impacts (p = .03 for trend). Regarding components of sarcopenia underlying this relationship, multivariable analyses revealed that gait speed (β 1.47 [95% CI 1.14, 1.89], [β-1] reflects the proportionate increase in high impacts per SD increase in exposure) and peak force (1.40 [1.07, 1.84]) were independently associated with high impacts.ConclusionsOlder women with sarcopenia experienced fewer bone-strengthening high impacts than those with presarcopenia or without sarcopenia. To increase bone strengthening activity in older women, interventions need to improve both lower limb muscle force and walking speed.

Where Can I Find Nutrition Resources for Children and Adolescents Participating in Youth Sports?

In addition to consuming a healthy eating pattern, regular physical activity is one of the most important things all Americans, including children and adolescents, can do to improve their health. The 2008 Physical Activity Guidelines for Americans, published by the US Department of Health and Human Services, describe the types and amounts of physical activity that offer substantial health benefits.1Office of Disease Prevention and Health Promotion. Physical Activity Guidelines. Washington, DC: US Department of Health and Human Services. https://health.gov/paguidelines/. Accessed July 12, 2017.Google Scholar Children and adolescents should do 60 minutes or more of physical activity daily. Most of that time should be spent doing either moderate- or vigorous-intensity aerobic activity. In addition, they should participate in muscle-strengthening and bone-strengthening activities at least 3 days a week. The “Be Active Your Way” blog is the official blog of the Physical Activity Guidelines for Americans, and it provides updates about the development of the second edition of the guidelines and insights from health and physical activity professionals about translating the guidelines into practice.2Office of Disease Prevention and Health Promotion. Be Active Your Way. Washington, DC: US Department of Health and Human Services. https://health.gov/news/category/blog-bayw/. Accessed May 30, 2017.Google Scholar A 2012 mid-course Physical Activity Guidelines report on “Strategies to Increase Physical Activity Among Youth” further emphasized the importance of physical activity for health in children and youth and outlined methods for achieving the recommended 60 minutes of physical activity per day, while noting that fewer than half of children meet the recommendations.3Office of Disease Prevention and Health Promotion. PAG Midcourse Report: Strategies to Increase Physical Activity Among Youth. Washington, DC: US Department of Health and Human Services. https://health.gov/paguidelines/midcourse/. Accessed July 12, 2017.Google Scholar Additional statistics and information about physical activity and health are available on the Centers for Disease Control and Prevention’s physical activity webpage.4National Center for Chronic Disease Prevention and Health Promotion, Division of Nutrition, Physical Activity, and Obesity. Facts about Physical Activity. Atlanta, GA: Centers for Disease Control and Prevention. https://www.cdc.gov/physicalactivity/data/facts.htm. Accessed May 30, 2017.Google Scholar Proper nutrition is a major factor that can help make participation in physical activity a positive experience for children and adolescents. Registered dietitian nutritionists may be called upon to talk with coaches, make presentations to players and their parents, or provide personalized nutrition counseling. An excellent resource for sports-related nutrition information is the Pediatric Nutrition Care Manual (PNCM).5Pediatric Nutrition Care Manual. Child athletes. Chicago, IL: Academy of Nutrition and Dietetics. https://www.nutritioncaremanual.org/topic.cfm?ncm_category_id=12&lv1=144615&ncm_toc_id=144615&ncm_heading=&. Accessed May 30, 2017.Google Scholar According to the PNCM, nutrient needs are similar for boys and girls prior to puberty. When a variety of foods are consumed, a child’s diet can meet nutrient needs by following the 2015-2020 Dietary Guidelines for Americans in conjunction with guidelines specified in ChooseMyPlate.gov. The PNCM states that for activities lasting less than 60 minutes, water is all that is needed for hydration. For activities longer than 60 minutes, other beverages, such as fluid-replacement drinks that contain additional carbohydrate and electrolytes, are recommended. Some studies suggest that the presence of flavoring, sodium, and carbohydrate in a beverage enhances thirst and is effective in reducing or preventing voluntary dehydration. Puberty, which occurs during adolescence, is characterized by increases in height and weight, completion of skeletal growth, increases in bone mass, changes in body composition, and sexual maturation. Children enter adolescence and begin puberty at varying ages. These changes result in increased nutrition needs, and optimal nutrition is key. In addition to physical growth, adolescents experience an increase in the ability to assess and address more complex situations and a significant increase in the desire for autonomy. The increased nutrient needs—along with more independence in decision-making regarding food choices and other influences such as peer pressure or the media—may put some adolescents at nutritional risk. Understanding the physical and cognitive changes occurring throughout adolescence can help nutrition and dietetics practitioners working with adolescents. The PNCM provides guidance and resources to assist with meeting the needs of the active child. It also addresses the unique nutritional needs of the child athlete in relation to growth and development and within the context of the Nutrition Care Process. A registered dietitian nutritionist, especially one that specializes in sports nutrition, can be an asset to the child who is becoming more active and to the child athlete who is already participating in sporting events that can vary greatly in skill levels.

Innovative Ways to Use Modern Technology to Enhance, Rather than Hinder, Physical Activity among Youth

It is recommended that each day youth get 60 minutes or more of moderate-to-vigorous physical activity that includes aerobic, muscle, and bone strengthening activities. The majority of youth, however, do not meet these physical activity guidelines. Children and adolescents spend on average seven hours engaging in sedentary “screen-based” activity each day. Lowered levels of youth leisure-time physical activity can be attributed at least in part to advancements in modern technology, most specifically video games, which have been shown to reduce energy expenditure throughout the day. Active video games, which offer easy “at home” access, fun and social interaction qualities, as well as goal-achievement feedback could serve as a suitable alternative to sedentary leisure-time activities. Youth cite several physical activity participation needs including skill development, fun, affiliation, excitement, fitness, and success. Interventions that consider these needs have the potential to decrease the risk of sedentary behavior among youth. Screen-based technologies, along with smartphone apps, represent excellent initial steps in combating sedentary behavior among youth. This article assesses (1) the potential health benefits of active video games, especially for youth who would otherwise be sedentary; and (2) opportunities to incorporate smart technology to foster long-term commitment.

Exercise Strategies for Children

Exercise Strategies for Children

Student Voice: Student Choice and Participation in Physical Education

Secondary students frequently disengage from participating in physical education and physical activity. The Centers for Disease Control and Prevention (CDC) recommends 60 minutes of vigorous aerobic activity per day, as well as muscle and bone strengthening activities on three or more days a week for children (CDC, n.d.). Physical education may be the only opportunity for school-age children to participate in physical activity (Trudeau & Shepard, 2008).This article reviews a high school selective physical education curriculum and the students' perceptions of the activities offered in the junior and senior years. Students expressed an interest in being able to have input into activity offerings, alluding to the current teacher-directed curriculum. Students preferred learning new games, skills, and activities for continued participation in adulthood.Student input in curriculum design may lead to a more student-centered and dynamic curriculum. Determining students' needs and interests is the initial step to modifying a curriculum in order to offer activities that provide students with meaningful experiences. Professional development opportunities are necessary to keep physical educators apprised of new trends and for physical educators to learn how to incorporate such activities into the curriculum. When students selected the activities, they were more likely to participate in physical education, and the activities and the curriculum were more meaningful from the students' perspective.

A systematic review of the efficacy and pharmacological profile of Herba Epimedii in osteoporosis therapy.

The purpose of this systematic review is to assess the efficacy and pharmacological profiles of Herba Epimedii in osteoporosis therapy. Four databases were extensively retrieved that include two Chinese electronic databases (VIP Information and CNKI) and two English electronic databases (CA and MEDLINE). Herba Epimedii has been an important traditional herbal medicine for centuries in China and other Asian countries. Recently, quite a few pharmacological effects of Herba Epimedii, its extracts and active components have been identified that include improving bone health and cardiovascular function, regulating hormone level, modulating immunological function, and inhibiting tumor growth. The anti-osteoporosis activity of Herba Epimedii and its extracts have attracted world-wide attention. The literature search has revealed that a lot of studies have recently been carried out related to the bone-strengthening activity of Herba Epimedii and some of its active compounds, such as total flavonoids and icariin. Pharmacokinetic and toxicity studies have confirmed the efficacy and safety of Herba Epimedii and its most abundant active component icariin, while only a few authors have reviewed the anti-osteoporosis properties of the plants. So we summarize the work of various investigators on the effects of Herba Epimedii, its extracts and active components against osteoporosis. The underlying mechanism of osteoprotective action, derivatives of icariin, animal models and cell lines used in the research were also reviewed in this paper.

Improving health-related fitness in children: The Fit-4-Fun randomized controlled trial

Background: Declining levels of physical fitness in children are linked to an increased risk of developing poor physical and mental health. Physical activity programs for children that involve regular high intensity physical activity, along with muscle and bone strengthening activities, have been identified by the World Health Organisation as a key strategy to reduce the escalating burden of ill health caused by non-communicable diseases. This paper reports the rationale and methods for a school-based intervention designed to improve physical fitness and physical activity levels of Grades 5 and 6 primary school children. Methods/Design: Fit-4-Fun is an 8-week multi-component school-based health-related fitness education intervention and will be evaluated using a group randomized controlled trial. Primary schools from the Hunter Region in NSW, Australia, will be invited to participate in the program in 2011 with a target sample size of 128 primary schools children (age 10-13). The Fit-4-Fun program is theoretically grounded and will be implemented applying the Health Promoting Schools framework. Students will participate in weekly curriculum-based health and physical education lessons, daily break-time physical activities during recess and lunch, and will complete an 8week (3 × per week) home activity program with their parents and/or family members. A battery of six healthrelated fitness assessments, four days of pedometery-assessed physical activity and a questionnaire, will be administered at baseline, immediate post-intervention (2-months) and at 6-months (from baseline) to determine intervention effects. Details of the methodological aspects of recruitment, inclusion criteria, randomization, intervention program, assessments, process evaluation and statistical analyses are described. Discussion: The Fit-4-Fun program is an innovative school-based intervention targeting fitness improvements in primary school children. The program will involve a range of evidence-based behaviour change strategies to promote and support physical activity of adequate intensity, duration and type, needed to improve health-related fitness. Trial Registration No: Australia and New Zealand Clinical Trials Register (ANZCTR): ACTRN12611000976987

The bone-strengthening activity of milk basic protein is not dependent on lactoferrin

Milk contains components important for bone health. We have previously reported that milk basic protein (MBP) enhances bone formation and suppresses bone resorption. Lactoferrin (LF), a basic iron-binding protein in milk, also improves bone metabolism. However, the contribution of LF to the bone-strengthening activity of MBP is unclear. Here we compared the effects of MBP and LF on bone cells in vitro and bone strength in vivo. MBP showed greater stimulatory effects than did LF on the proliferation and differentiation of osteoblasts. MBP was also more effective than LF in terms of inhibiting bone resorption by osteoclasts. The force required to break bones in ovariectomised rats was significantly greater in rats fed 0.1% MBP than in rats fed 0.1% LF. These results suggest that the effects of MBP on bone metabolism are not solely due to LF; rather, multiple components in MBP may act together to improve bone metabolism.

Improving health-related fitness in children: the Fit-4-Fun randomized controlled trial study protocol.

BackgroundDeclining levels of physical fitness in children are linked to an increased risk of developing poor physical and mental health. Physical activity programs for children that involve regular high intensity physical activity, along with muscle and bone strengthening activities, have been identified by the World Health Organisation as a key strategy to reduce the escalating burden of ill health caused by non-communicable diseases. This paper reports the rationale and methods for a school-based intervention designed to improve physical fitness and physical activity levels of Grades 5 and 6 primary school children.Methods/DesignFit-4-Fun is an 8-week multi-component school-based health-related fitness education intervention and will be evaluated using a group randomized controlled trial. Primary schools from the Hunter Region in NSW, Australia, will be invited to participate in the program in 2011 with a target sample size of 128 primary schools children (age 10-13). The Fit-4-Fun program is theoretically grounded and will be implemented applying the Health Promoting Schools framework. Students will participate in weekly curriculum-based health and physical education lessons, daily break-time physical activities during recess and lunch, and will complete an 8-week (3 × per week) home activity program with their parents and/or family members. A battery of six health-related fitness assessments, four days of pedometery-assessed physical activity and a questionnaire, will be administered at baseline, immediate post-intervention (2-months) and at 6-months (from baseline) to determine intervention effects. Details of the methodological aspects of recruitment, inclusion criteria, randomization, intervention program, assessments, process evaluation and statistical analyses are described.DiscussionThe Fit-4-Fun program is an innovative school-based intervention targeting fitness improvements in primary school children. The program will involve a range of evidence-based behaviour change strategies to promote and support physical activity of adequate intensity, duration and type, needed to improve health-related fitness.Trial Registration NoAustralia and New Zealand Clinical Trials Register (ANZCTR): ACTRN12611000976987

Progress and future directions on physical activity research among youth.

There is strong evidence to support the benefits of regular physical activity for children and adolescents (heretofore referred to as "youth"). Evidence includes improved cardiorespiratory fitness, muscular fitness, bone health, body composition, and cardiovascular and metabolic health biomarkers. Importantly, physical inactivity is a modifiable risk factor for lifestyle-related chronic diseases and conditions and may track through adulthood. Because of the potential benefits and modifiable nature of the behavior, the "2008 Physical Activity Guidelines for Americans" recommends 1 hour or more of daily physical activity for youth. Most of the time should be spent in either moderate-or vigorous-intensity aerobic activities and should also include muscle and bone strengthening activities. The 2010 World Health Organization "Global Recommendations for Physical Activity and Health" supports similar guidelines for youth.

Systematic review of the health benefits of physical activity and fitness in school-aged children and youth

BackgroundThe purpose was to: 1) perform a systematic review of studies examining the relation between physical activity, fitness, and health in school-aged children and youth, and 2) make recommendations based on the findings.MethodsThe systematic review was limited to 7 health indicators: high blood cholesterol, high blood pressure, the metabolic syndrome, obesity, low bone density, depression, and injuries. Literature searches were conducted using predefined keywords in 6 key databases. A total of 11,088 potential papers were identified. The abstracts and full-text articles of potentially relevant papers were screened to determine eligibility. Data was abstracted for 113 outcomes from the 86 eligible papers. The evidence was graded for each health outcome using established criteria based on the quantity and quality of studies and strength of effect. The volume, intensity, and type of physical activity were considered.ResultsPhysical activity was associated with numerous health benefits. The dose-response relations observed in observational studies indicate that the more physical activity, the greater the health benefit. Results from experimental studies indicate that even modest amounts of physical activity can have health benefits in high-risk youngsters (e.g., obese). To achieve substantive health benefits, the physical activity should be of at least a moderate intensity. Vigorous intensity activities may provide even greater benefit. Aerobic-based activities had the greatest health benefit, other than for bone health, in which case high-impact weight bearing activities were required.ConclusionThe following recommendations were made: 1) Children and youth 5-17 years of age should accumulate an average of at least 60 minutes per day and up to several hours of at least moderate intensity physical activity. Some of the health benefits can be achieved through an average of 30 minutes per day. [Level 2, Grade A]. 2) More vigorous intensity activities should be incorporated or added when possible, including activities that strengthen muscle and bone [Level 3, Grade B]. 3) Aerobic activities should make up the majority of the physical activity. Muscle and bone strengthening activities should be incorporated on at least 3 days of the week [Level 2, Grade A].

Effect of antler extract on corticosteroid-induced avascular necrosis of the femoral head in rats

Ethnopharmacological relevance Deer antler, traditionally used as a tonic and valuable drug in oriental medicine, has been considered to possess bone-strengthening activity and effectively used in bone diseases therapy. Aim of the study The present study was designed to investigate therapeutic effect of antler extract on avascular necrosis of the femoral head (ANFH) induced by corticosteroids in rats. Materials and methods Rats were intragluteally injected with dexamethasone at 50 mg/kg twice per week for 6 weeks to induce ANFH. Then the rats were treated with antler extract by oral gavage at 200 mg/kg, 400 mg/kg and 800 mg/kg once per day for 60 days. The concentration of hydroxyproline and hexosamine in serum was measured and the ultrastructure of femoral head was examined. In vitro, effect of the drug-containing serum of antler extract on proliferation and differentiation of primary osteoblasts were investigated by MIT assay, ALP activity assay and cell cycle analysis. Results After treatment with antler extract, the degree of necrosis induced by dexamethasone was significantly reduced, hydroxyproline was significantly decreased, and hexosamine and the ratio of hexosamine/hydroxyproline were significantly increased. The drug-containing serum of antler extract promotes osteoblastic proliferation through regulation of cell cycle progression. Conclusions The results suggest that antler extract has a positive curative effect on ANFH by promoting osteoblastic proliferation.