Bone Strengthening Research Articles

What are the health benefits of muscle and bone strengthening and balance activities across life stages and specific health outcomes?

Many activities of daily living require muscular strength and power as well as balance. Consequently, preserving musculoskeletal function is a prerequisite for maintaining mobility and independent living during ageing. Estimates suggest that the prevalence of physical activity guidelines for strength and balance is low. Review of reviews of: a) observation studies of the prospective association between measures of musculoskeletal fitness and health outcomes and b) randomised controlled trials of resistance, balance and skeletal impact training exercises on bone health, risk of falls, physical function, motor and cognitive function, quality of life and activities of daily living. Preserving muscular strength/power in middle and older age is associated with a reduced risk of all-cause and cardiovascular mortality. Impaired muscular strength/power and balance is associated with an increased risk of falls and lower bone mineral content. Regular supervised exercise incorporating high intensity resistance training, vertical impacts and a balance challenge are most likely to be beneficial to health and wellbeing, bone health and reduce the risks of falls. Adults in late middle and older age would benefit from a regular program of exercise that incorporates high intensity resistance training, impact exercises and balance challenges.

Therapist's practice patterns for subsequent fall/osteoporotic fracture prevention for patients with a distal radius fracture

Study DesignCross-sectional survey. IntroductionMultifactorial risk factor screening and treatment is needed for subsequent falls/osteoporotic fractures prevention (SFOFP), given the elevated risk among patients with distal radius fracture (DRF). Purpose of the StudyThe primary objective was to describe hand therapists' knowledge and clinical practice patterns for assessment, treatment, referral, and education with respect to SFOFP for patients with DRF older than 45 years. Secondary objective was to explore therapist's preferences in content and delivery of knowledge translation tools that would support implementation of SFOFP. MethodsA cross-sectional multinational (Canada, the United States, and India) survey was conducted among 272 therapists from August to October 2014. Completed surveys were analyzed descriptively. ResultsSurveys were completed by 157 therapists. Most respondents were from the United States (59%), certified hand therapists (54%), and females (87%). Although 65%-90% believed that they had knowledge about SFOFP assessment, treatment, and referral options, 55% did not include it in their routine practice for patients with DRF. Most assessed medication history (82%) and never used a Fracture Risk Assessment Tool (90%) or lower extremity muscle strength testing (54%) to identify those at risk of secondary fractures. With respect to treatment, approximately 33% always used upper extremity muscle strengthening exercises. Most reported rarely (sometimes to never) using balance (79%), lower extremity muscle strengthening (85%), bone strengthening (54%), or community-based physical activity (72%) programs. Similarly, when surveyed about patient education, therapists rarely (sometimes to never) advised patients about web-based resources (94%), regular vision testing (92%), diet for good bone health (87%), bone density evaluation (86%), footwear correction (73%), and hazard identification (67%). Most hand therapists were interested to receive more information on SFOFP for patients with DRF. Nearly one-half preferred to have Web sites for patients, and two-fifth were in favor of pamphlets for patients. ConclusionCurrent practice patterns reveal care gaps and limited implementation with respect to SFOFP for patients with DRF. Future research should focus on web-based educational/knowledge translation strategies to promote implementation of multifactorial fall risk screening and hand therapist's engagement in SFOFP for patients with DRF.

Effectiveness of various isometric exercises at improving bone strength in cortical regions prone to distal tibial stress fractures.

A computational model was used to compare the local bone strengthening effectiveness of various isometric exercises that may reduce the likelihood of distal tibial stress fractures. The developed model predicts local endosteal and periosteal cortical accretion and resorption based on relative local and global measures of the tibial stress state and its surface variation. Using a multisegment 3-dimensional leg model, tibia shape adaptations due to 33 combinations of hip, knee, and ankle joint angles and the direction of a single or sequential series of generated isometric resultant forces were predicted. The maximum stress at a common fracture-prone region in each optimized geometry was compared under likely stress fracture-inducing midstance jogging conditions. No direct correlations were found between stress reductions over an initially uniform circular hollow cylindrical geometry under these critical design conditions and the exercise-based sets of active muscles, joint angles, or individual muscle force and local stress magnitudes. Additionally, typically favorable increases in cross-sectional geometric measures did not guarantee stress decreases at these locations. Instead, tibial stress distributions under the exercise conditions best predicted strengthening ability. Exercises producing larger anterior distal stresses created optimized tibia shapes that better resisted the high midstance jogging bending stresses. Bent leg configurations generating anteriorly directed or inferiorly directed resultant forces created favorable adaptations. None of the studied loads produced by a straight leg was significantly advantageous. These predictions and the insight gained can provide preliminary guidance in the screening and development of targeted bone strengthening techniques for those susceptible to distal tibial stress fractures.

Physical activity and family-based obesity treatment: a review of expert recommendations on physical activity in youth.

Targeting physical inactivity in children is pertinent to aiding in the decrease of childhood obesity rates. Only 33% of adolescents are obtaining the recommended goal of at least 60 min of physical activity per day. The objectives of this review are to summarize professional recommendations for physical activity and exercise in children and adolescents, and identify family-centred strategies that can be implemented by weight management clinicians. Clinically oriented recommendations and policy statements from professional organizations were identified through literature and internet searches, summarized using rubrics of aerobic, muscle strengthening and bone strengthening exercise, then examined for details on family-based focus, inclusion of child developmental stage and age, and application to the prevention and treatment of obesity. Current recommendations give guidelines for the amount of physical activity that children should acquire and how many days a week activities should occur. However, available guidelines need an improved approach to addressing the role of the parents and caregivers in targeting physical activity and weight management in youth. Efforts must be taken in order to make sure that the types of physical activity offered are both suitable and enjoyable. Sports, games, free play and other age appropriate activities are adequate ways to increase moderate to vigorous physical activity in children. Differentiating physical activities types in accordance with developmental stage, level of enjoyment, and family characteristics is needed to establish sustainable habits. One paediatric obesity program has developed approaches to teaching families fun and engaging ways to be active together.

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.

Ideas and methods on efficient screening of traditional medicines for anti-osteoporosis activity based on M-Act/Tox integrated evaluation using zebrafish

The increasingly apparent liver injury problems of bone strengthening Chinese medicines have brought challenges for clinical application, and it is necessary to consider both effectiveness and safety in screening anti-osteoporosis Chinese medicines. Metabolic transformation is closely related to drug efficacy and toxicity, so it is significant to comprehensively consider metabolism-action/toxicity(M-Act/Tox) for screening anti-osteoporosis Chinese medicines. The current evaluation models and the number of compounds(including metabolites) severely restrict efficient screening in vivo. By referring to previous relevant research and domestic and abroad literature, zebrafish M-Act/Tox integrative method was put forward for efficiently screening anti-osteoporosis herb medicines, which has organically integrated zebrafish metabolism model, osteoporosis model and toxicity evaluation method. This method can break through the bottleneck and blind spots that trace compositions can't achieve efficient and integrated in vivo evaluation, and realize both efficient and comprehensive screening on anti-osteoporosis traditional medicines based on in vivo process taking both safety and effectiveness into account, which is significant to accelerate discovery of effective and safe innovative traditional Chinese medicines for osteoporosis.

Strength adaptations of the tibia bone for prescribed sets of isometric forces and joint angles

The isometric exercise induced tibial bone strength adaptations due to various prescribed net resultant forces generated by a leg arranged with specified hip, knee, and ankle joint angles were examined using a computationally based bone shape adaptation model. With the leg straight, or the knee flexed at 90°, and the hip either neutral or flexed by 45°, a force was repeatedly generated at the toe either anteriorly, posteriorly, superiorly, or inferiorly, in paired sequences of these directions, or in a clockwise pattern of all four directions. Model-predicted individual muscle forces, amounts of cortical bone surface accretion or resorption, and the resulting changes in bone stress distributions were compared. Similarities between adaptations to specific combinations of joint angles and net resultant force directions were found to follow similarities in the bone stress distributions rather than in muscle activity. The ratio of standard deviation to the surface-averaged measure of local stress was a good predictor of potential improvement in overall stress state uniformity. With flexed knee and neutral hip, greater adaptive improvements in tibial surface stress uniformity were found than with both joints flexed. Flexed configurations caused greater changes and overall strength improvements than exercises performed with a straight leg. Regions of local tibial cortical thickening were identified for specific joint angles and single-load resultant force directions. Sequential series of loads were also identified to enhance these effects and mitigate concurrent thinning in other regions. The presented information can aid in the design and analysis of targeted muscle and bone strengthening exercises.

Cytotoxic effects of zoledronic acid-loaded hydroxyapatite and bone cement in malignant tumors.

Metastatic and primary bone tumors are malignant tumors affecting the skeleton. Although the prognosis of patients with these tumors has improved with the development of effective chemotherapy, the challenges of local recurrence, subsequent osteolysis, degradation of bone strength and unresectable tumors persist. Local control of these tumors is therefore a key strategy to address these limitations. The third-generation bisphosphonate (BP), zoledronic acid (ZOL), has been demonstrated to reduce osteoclasts and exhibited potent antitumor effects in a number of malignancies. Hydroxyapatite (HA) and polymethyl methacrylate (PMMA) bone cement are used in orthopedic surgery as bone graft substitutes, for implant arthroplasty and bone strengthening, and as a sustained-release system for drugs such as antibiotics. At present, the antitumor effects of ZOL-loaded HA in vitro or in vivo or of ZOL-loaded bone cement in vivo have not been described. Therefore, the present study assessed the effects of ZOL-loaded HA and bone cement in malignant tumor cells. The two materials exerted strong antitumor effects against osteosarcoma, fibrosarcoma, synovial sarcoma, renal cancer, prostate cancer and lung cancer cells upon releasing ZOL. The antitumor effects of ZOL-loaded HA were less potent compared with those of ZOL-loaded bone cement, possibly as BPs exhibit higher affinity to HA. ZOL-loaded bone cement also exerted antitumor effects against pulmonary metastases and primary lesions, without exhibiting systemic toxicity in vivo. These results demonstrate that these materials may be beneficial for the treatment of malignant bone tumors, including metastatic bone tumors. In addition, as these materials are already in clinical use, such applications may be easily implemented.

Effects of the combined Herba Epimedii and Fructus Ligustri Lucidi on bone turnover and TGF-β1/Smads pathway in GIOP rats

Ethnopharmacological relevanceKidney deficiency is the main pathogenesis of osteoporosis based on the theory of “kidney governing bones” in traditional Chinese medicine (TCM). Combined Herba Epimedii and Fructus Ligustri Lucidi, based on traditional Chinese formula Er-Zhi pills, were frequently used in TCM formulas that were prescribed for kidney tonifying and bone strengthening. However, it is unclear whether the combination of the two herbs may have a protective influence on glucocorticoid-induced osteoporosis (GIOP). The objective of this study was to evaluate the therapeutic effects and the underlying molecular mechanism of the decoction and the active fractions of the combined herbs in GIOP rats. Materials and methodsMale Sprague-Dawley rats were divided into seven groups, including the normal control (NC), GIOP model (MO), active fractions low (100mg/kg, LAF), active fractions high (200mg/kg, HAF), decoction low (3.5g/kg, LD), decoction high (7g/kg, HD) and Calcium with Vitamin D3 (0.2773g/kg, CaD)-treated group. The GIOP model was established by intramuscular injection of dexamethasone (1mg/kg) twice a week for 8 weeks. Different kinds of indicators were measured, including bone mineral density (BMD), bone biomechanical properties, serum bone alkaline phosphatase (b-ALP), serum bone γ-carboxyglutamic acid-containing protein (BGP), serum bone morphogenetic protein-2 (BMP-2), serum tartrate-resistant acid phosphatase (TRACP) and serum carboxy terminal cross linked telopeptide of typeⅠcollagen (ICTP), bone mineral content (BMC) and bone structured histomorphometry. The protein and mRNA expression of TGF-β1, Smad2, Smad3, Smad4 and Smad7 were detected by Western blotting (WB) and quantitative real time polymerase chain reaction (qRT-PCR), respectively. ResultsAdministration of combined Herba Epimedii and Fructus Ligustri Lucidi decoction and combined active fractions could significantly prevent GC-induced bone loss by increasing the contents of serum b-ALP, BGP and BMP-2 as the markers of bone formation, reducing the serum TRACP and ICTP contents to inhibit bone resorption and enhancing BMC. They could also attenuate biomechanical properties and BMD reduction, deterioration of trabecular architecture in MO rats. The mRNA and protein expressions of TGF-β1, smad2, smad3 and smad4 were up-regulated, and the mRNA and protein expression of Smad7 was down-regulated following combined Herba Epimedii and Fructus Ligustri Lucidi treatment. ConclusionCombination of Herba Epimedii and Fructus Ligustri Lucidi exhibited protective effects on promoting bone formation and precluding bone resorption. The underlying mechanism may be attributed to its regulations on TGF-β1/Smads pathway. The substance bases of the combined herbs on anti-osteoporosis were total flavonoids of Herba Epimedii, total iridoids and flavonoids of Fructus Ligustri Lucidi.

LC-MS/MS를 이용한 식품 중 천속단과 한속단 지표성분 동시분석

Phlomis umbrosa and Dipsacus asperoides are distinct species, even though they have a similar appearance. Dipsacus asperoides is used as a Chinese medicinal plant for and has bone strengthening and fracture healing but Phlomis umbrosa has no effect on bone growth. Recently, these plants were used in children’s food to improve their bone growth, without distinction in food. Intakes of Dipsacus asperoides in food may be dangerous, because it has never been used in food and its safety has never been tested in humans. We developed liquid chromatography with tandem mass spectrometry method to distinguish these plants in food. The method was validated for linearity, limits of detection, limits of quantification, accuracy and precision. In 5 of 17 samples, we identified Dipsacus asperoides, containing loganin 0.19-14.45 μg/mL, sweroside 0.13-4.61 μg/mL and akebia saponin D 0.59-19.29 μg/mL. The developed method might be useful to identify Dipsacus asperoides in adulterated food.

Muscle fiber excitation system.

Persons unable to exercise due to old age, immobility or medical condition may develop low bone density, decline in muscle contraction, blood pooling or clot. Due to musculoskeletal fragility caution is required in bone and muscle strengthening. Similarly, caution is required to use anticoagulant drug to prevent blood clot due to side effect, and compression devices are not as effective as drug. This paper presents a transcutaneous muscle fiber excitation system adaptable for use in seated, walking or lying position. Clinical trials will determine performance in pathological cases.

Physical Improvement and Biological Maturity of Young Athletes (11-12 Years) with Systematic Training.

The aim of this study was to investigate the influence of systematic training in physical growth and biological maturity in prepubertal males and estimate how this affects the physical growth and skeletal maturity. 177 primary school students of the fifth and sixth grade, from schools in Alexandroupolis, participated voluntarily in our study. Questionnaires were used in order to measure physical activity levels. The subjects were subdivided into two groups; control group (prepubertal, whose physical activity was the physical education of their school and which had never participated in systematic training, n = 95) and experimental group (prepubertal, whose weekly physical activity included physical education in their schools and additionally 3-4 training units organized training in various sports clubs in the city, n = 82). The following parameters were recorded: biological age measured by determination of skeletal age; bone density measured by ultrasound methods; anthropometric and morphological features such as height, body composition, selected diameters, circumferences and skinfolds; motor ability features. The experimental group exhibited older biological age (p = 0.033), higher bone density (p < 0.001), lower BMI and body fat (p < 0.001), better anthropometric features and higher performance throughout all motor ability tests (p < 0.05), compared to the control group. The present study demonstrates that systematic physical activity has a positive effect on both the physical and biological maturity of pre-pubertal children. This effect is mainly expressed in bone strengthening as a result of the increased bone density and in improvement of the kinetic skills of pupils who participated in organized extracurricular sport-activities.

The NYU Osteoporosis Model of Care Experience.

Introduction:Participants who sustain a fragility fracture are at increased risk for subsequent fractures. Despite the consequences of recurrent fractures, bone mineral density (BMD) testing and treatment rates for osteoporosis after a fracture remain low. The New York University (NYU) Langone Osteoporosis Model of Care was developed to identify women at increased risk for recurrent fractures and to reduce the rates of subsequent fracture through patient and physician education.Methods:Women aged 50 years and older who had a fracture and received their care at NYU affiliated hospitals were contacted via mail after discharge. Participants were provided educational materials explaining decreased bone strength and its possible relationship to their fracture and were asked to complete a questionnaire. One year postfracture, participants were sent follow-up questionnaires requesting their most recent fracture treatment and BMD information. Educational material was also provided to the treating orthopedic surgeons.Results:Overall, 524 patients were contacted and 210 (40%) enrolled. By the end of 24 months, 92 participants completed their 1-year questionnaire (44% of the enrollees). Forty-two (46%) participants had undergone new BMD testing and 37 (40%) were receiving antiresorptive medications, including 6 (6%) who had not been prescribed these medications before enrolling in the program.Conclusions:The Osteoporosis Model of Care is a simple and cost-effective educational program, which improved comprehensive fracture care in an actual clinical setting. Patient enrollment remains a challenge in implementing the program. Our program highlights difficulties in providing community-dwelling participants with appropriate postfracture care. With increasing concern among the public regarding the use of bone strengthening medications and continued low postfracture treatment rates, educating patients with high fracture risk is critical to reducing the rate of subsequent fracture. Our Model of Care Program demonstrates both the success and limitations of a postfracture educational approach using discharge diagnosis data to identify patients with fracture.

Follistatin-like 3 is a mediator of exercise-driven bone formation and strengthening

Exercise is vital for maintaining bone strength and architecture. Follistatin-like 3 (FSTL3), a member of follistatin family, is a mechanosensitive protein upregulated in response to exercise and is involved in regulating musculoskeletal health. Here, we investigated the potential role of FSTL3 in exercise-driven bone remodeling. Exercise-dependent regulation of bone structure and functions was compared in mice with global Fstl3 gene deletion (Fstl3−/−) and their age-matched Fstl3+/+ littermates. Mice were exercised by low-intensity treadmill walking. The mechanical properties and mineralization were determined by μCT, three-point bending test and sequential incorporation of calcein and alizarin complexone. ELISA, Western-blot analysis and qRT-PCR were used to analyze the regulation of FSTL3 and associated molecules in the serum specimens and tissues. Daily exercise significantly increased circulating FSTL3 levels in mice, rats and humans. Compared to age-matched littermates, Fstl3−/− mice exhibited significantly lower fracture tolerance, having greater stiffness, but lower strain at fracture and yield energy. Furthermore, increased levels of circulating FSTL3 in young mice paralleled greater strain at fracture compared to the lower levels of FSTL3 in older mice. More significantly, Fstl3−/− mice exhibited loss of mechanosensitivity and irresponsiveness to exercise-dependent bone formation as compared to their Fstl3+/+ littermates. In addition, FSTL3 gene deletion resulted in loss of exercise-dependent sclerostin regulation in osteocytes and osteoblasts, as compared to Fstl3+/+ osteocytes and osteoblasts, in vivo and in vitro. The data identify FSTL3 as a critical mediator of exercise-dependent bone formation and strengthening and point to its potential role in bone health and in musculoskeletal diseases.

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.

Tiger Image on Medicinal Plasters Serve as a Cue for Traditional Medicine Consumers

In the past, Musk and Tiger Bone Plaster (Tiger Bone Plaster for shorter) was one of most common nonprescription Traditional Chinese Medicine (TCM). Since 1993, China banned all trade in tiger bones and its derivatives in 1993. Musk deer were up-listed as Category I State Key Protected Wild Animal Species in China in 2002. The plaster manufactures changed the prescription of Tiger Bone Plaster and used synthetic musk and herb medicines and changed the name of Tiger Bone Plaster to “Musk and Bone Strengthening Plaster” but packages of some brands of the plasters still carry a tiger’s image on it. Thus, consumers still consider the plasters as “Tiger Bone Plaster” because of the tiger image on the package. To investigate the consumer perception and behaviors of “Musk and Bone Strengthening Plaster”, we surveyed 418 citizens in Beijing in 2014. We found that 43.78% of respondents alleged that they had used “Tiger Bone Plaster”. When we inquired, almost all of respondents confirmed that the plasters they had used were “Musk and Bone Strengthening Plaster”. Presumably, tiger’s image on the plaster package produces a conditional stimulus to the consumers. Consumers preferred buying the plasters packed with tiger’s image printed on the package. In fact, no people had really consumed Tiger Bone Plaster in this investigation. For the sake of protecting tigers, we argue the manufacturers to remove the tiger image from the “Musk and Bone Strengthening Plaster” according to the regulations of CITES.

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.

D-36 Free Communication/Poster - Ultrasound

PURPOSE: The molecular mechanism of bone strengthening with exercise remains unclear. We have identified a molecule, follistatin-like 3 (FSTL3), that may drive mechanical load-dependent bone remodeling. METHODS: Female Sprague Dawley rats (12-14 wks, n=10), wild-type (Fstl3+/+, 10-12 wks, n=10) or homozygous Fstl3-/- C57Bl/6 mice (10-12 wks, n=10) were subjected to treadmill walking (EX) for 45 min/day. After 0, 2, 5 or 15 days of EX, gene expression was analyzed by quantitative real time polymerase chain reaction, Western blots, or immunohistochemistry of the trabecular bone/bone marrow at distal femur ends. Bone mineral apposition rates were assessed by administration of Calcein and Alizarin complexones on day 3 and 12. Statistical analysis was performed by one-way ANOVA with Tukey’s post hoc or T-test. RESULTS: Gene expression analysis revealed that EX stimulated Fstl3 mRNA expression by 6 fold on day 2, and mRNA declined to basal levels by day 5. Minimal FSTL3 protein expression was exhibited in the control non-EX trabecular bone, but a robust increase in FSTL3 expression was observed in EX rat femurs at days 2 and 5. Non-EX mice exhibited a significantly narrow distance between the Calcein and Alizarin incorporation and limited bone deposition. EX Fstl3+/+ and Fstl3+/- mice demonstrated a significant increase in bone deposition on the endosteal surface of the femurs not observed in Fstl3-/- mice. Representative stress-strain curves of the cortical bone of the Fstl3+/+ and Fstl3 -/- femurs revealed that strain at ultimate strength of femurs from Fstl3+/+ mice was approximately 25% > than that of Fstl3 -/- mice. Furthermore, the yield strain and yield energy were significantly upregulated by EX in Fstl3+/+, but not in Fstl3-/- mice. CONCLUSION: FSTL3 is a mechanoresponsive protein that may provide a new paradigm for investigating EX-driven bone formation as well as a marker to monitor the effects of EX on bone in health and disease.

Varying whole body vibration amplitude differentially affects tendon and ligament structural and material properties

Whole Body Vibration (WBV) is becoming increasingly popular for helping to maintain bone mass and strengthening muscle. Vibration regimens optimized for bone maintenance often operate at hypogravity levels (<1G) and regimens for muscle strengthening often employ hypergravity (>1G) vibrations. The effect of vibratory loads on tendon and ligament properties is unclear though excessive vibrations may be injurious. Our objective was to evaluate how tendon gene expression and the mechanical/histological properties of tendon and ligament were affected in response to WBV in the following groups: no vibration, low vibration (0.3G peak-to-peak), and high vibration (2G peak-to-peak). Rats were vibrated for 20min a day, 5 days a week, for 5 weeks. Upon sacrifice, the medial collateral ligament (MCL), patellar tendon (PT), and the Achilles Tendon (AT) were isolated with insertion sites intact. All tissues were tensile tested to determine structural and material properties or used for histology. Patellar tendon was also subjected to quantitative RT-PCR to evaluate expression of anabolic and catabolic genes. No differences in biomechanical data between the control and the low vibration groups were found. There was evidence of significant weakness in the MCL with high vibration, but no significant effect on the PT or AT. Histology of the MCL and PT showed a hypercellular tissue response and some fiber disorganization with high vibration. High vibration caused an increase in collagen expression and a trend for an increase in IGF-1 expression suggesting a potential anabolic response to prevent tendon overuse injury.

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