Quantifying the relationship between mechanical loading and the skeletal response in pre- and early-pubertal girls

PURPOSE
Before exercise prescription for bone health can be recommended, the relationship between mechanical loading characteristics and the skeletal response need to be quantified. We asked i) does moderate impact exercise result in a greater gain in BMC than low impact exercise, ii) what are the loading characteristics associated with a moderate and low impact exercise program and does this differ from non-structured play?, and iii) does loading history affect the osteogenic response to a moderate or low impact program?

METHODS
Sixty-eight pre- and early-pubertal girls (aged 8.9 +/- 0.2 yrs) were randomized to take part in a moderate or low impact exercise program 3 times/wk for 8.5 mnths. The number and type of loads associated with the exercise classes and non-structured play (recess) were assessed from video footage. The magnitude of load was assessed using a pedar in-sole mobile system. Hours of moderate and high impact organized sport were assessed from a physical activity questionnaire.

RESULTS
The moderate and low impact exercise programs consisted of -400 impacts per class, but the jumping, hopping and dynamic activities performed during the moderate impact program produced forces ranging from 2 to 4 times body weight (BW) compared to -1 BW for the low impact program. Moderate impact exercise resulted in a 2.7% greater gain in BMC at the tibia compared to the low impact exercise. The moderate impact exercise program consisted of fewer low impacts (1-2 BW) and a higher number of moderate impacts (2-4BW) compared to those typically performed during non-structured play. There were greater gains in BMC in subjects participating in the moderate versus the low impact exercise programs who participated in 2 to 3 hours of moderate impact sports outside school (2.5% to 4.5%, p

CONCLUSION
Approximately 400 impacts ranging 2-4 BW, 3 times/wk was enough stimuli to result in an osteogenic response in normally active girls; even in those actively involved in moderate impact sports outside school.

Is growth inhibited in non-elite competitive female gymnasts?

PURPOSE
We asked: 1) is statural growth inhibited in non-elite competitive female gymnasts?; and 2) if growth is reduced, is the effect similar for legs and spine?

METHODS
Height(Ht), sitting height(StHt) and leg length(LL) were measured in gymnasts and controls at baseline and every 12 mths for 2 yrs. Pubertal status was assessed by Tanner stage. Gymnasts were from USGF levels 4–10 and trained 7.5 to 22.5 hrs/wk. Age-adjusted Z-scores were determined for gymnasts on the anthropometric measures and based on linear regression analyses of data for 45 controls.

RESULTS
At baseline, pre-(N=40), peri-(N=16) and post-pubertal(N=11) gymnasts were shorter than controls(-0.9 to -1.3 SD, p < 0.01). In pre- and peri-pubertal gymnasts, this was due to a reduction in StHt (-0.8 to -1.3 SD) and LL (-0.8 to -1.1 SD)(p < 0.01). In post-pubertal gymnasts, StHt (-0.8 SD) was reduced (p < 0.05). No differences were observed in z-score deficits between pubertal groups, nor were there any differences in StHt and LL deficits. During 12 mths follow-up in 39 gymnasts, deficits in Ht z-scores were reduced further in pre-pubertal gymnasts (-0.2 SD, p < 0.001) due to a greater increase in the deficit in LL (-0.3 SD, p < 0.001). While the magnitude of z-score deficits for peri-pubertal gymnasts remained unchanged, Ht z-scores improved in post-pubertal gymnasts(+0.2SD, p < 0.05) due primarily to an increase in StHt (+0.4 SD, p < 0.01). Similar results were found in 16 gymnasts followed for 2 yrs.

CONCLUSION
Although small size may relate to self-selection for gymnastics, some non-elite female gymnasts may experience attenuated growth during early puberty due mainly to reduced leg growth. The increased growth observed in post-pubertal gymnasts is consistent with catch-up growth associated with delayed maturation.

Age does not influence the bone response to treadmill exercise in female rats

Purpose: Because it is believed that bone may respond to exercise differently at different ages, we compared bone responses in immature and mature rats after 12 wk of treadmill running.

Methods: Twenty-two immature (5-wk-old) and 21 mature (17-wk-old) female Sprague Dawley rats were randomized into a running (trained, N = 10 immature, 9 mature) or a control group (controls, N = 12 immature, 12 mature) before sacrifice 12 wk later. Rats ran on a treadmill five times per week for 60-70 min at speeds up to 26 m[middle dot]min-1. Both at baseline and after intervention, we measured total body, lumbar spine, and proximal femoral bone mineral, as well as total body soft tissue composition using dual-energy x-ray absorptiometry (DXA) in vivo. After sacrificing the animals, we measured dynamic and static histomorphometry and three-point bending strength of the tibia.

Results: Running training was associated with greater differences in tibial subperiosteal area, cortical cross-sectional area, peak load, stiffness, and moment of inertia in immature and mature rats (P < 0.05). The trained rats had greater periosteal bone formation rates (P < 0.01) than controls, but there was no difference in tibial trabecular bone histomorphometry. Similar running-related gains were seen in DXA lumbar spine area (P = 0.04) and bone mineral content (BMC;P = 0.03) at both ages. For total body bone area and BMC, the immature trained group increased significantly compared with controls (P < 0.05), whereas the mature trained group gained less than did controls (P < 0.01).

Conclusion: In this in vivo model, where a similar physical training program was performed by immature and mature female rats, we demonstrated that both age groups were sensitive to loading and that bone strength gains appeared to result more from changes in bone geometry than from improved material properties.

Processes influencing the development of graduate nurse capabilities in clinical risk management : an Australian study

Objectives: To explore and describe key processes influencing the development of graduate nurse capabilities in clinical risk management (CRM).

Methods: This study was undertaken using an exploratory descriptive case study method. Four sample units of analysis were used, notably: 2 cohorts of graduate nurses (n = 11) undertaking a 12-month graduate nurse transition program; key stakeholders (n = 34), that is, nurse unit managers, clinical teachers, preceptors, a quality manager, a librarian, and senior nurse administratiors employed by the participating health service; patient outcome data; and pertinent literature.

Results: Data strongly suggested that graduate nurse capabilities in CRM were most influenced not by their supposed lack of clinical knowledge and skills but by their lack of corporate knowledge. The failure to provide new graduate nurses with pertinent information on CRM at the beginning of their employment and thereafter at pertinent intervals during the graduate nurse year program aslo hindered the development of their capabilities to manage clinical risk.

Conclusions: Management and educational processes pertinent to informing and involving new graduate nurses in a hospital's local CRM program (including information about the organization's local policies and procedures) need to be implemented systematically at the very beginning of a new graduate's employment and thereafter throughout the remainder of the graduate nurse year.

Beyond the BARRIERS scale : commonly reported barriers to research use

The evidence-based practice movement has highlighted the importance of translating research evidence into practice. However, the gap between research and practice points to the existence of significant barriers to research use. To identify the most commonly cited barriers to the use of research in practice, the findings arising from studies that used the Barriers to Research Utilization Scale are examined. Based on these findings, the authors discuss and make recommendations to assist nurse administrators in overcoming universally reported barriers to research use.

Arterial compliance in obese subjects is improved with dietary plant n-3 fatty acid from flaxseed oil despite increased LDL oxidizability

The compliance or elasticity of the arterial system, an important index of circulatory function, diminishes with increasing cardiovascular risk. Conversely, systemic arterial compliance improves through eating of fish and fish oil. We therefore tested the value of high intake of alpha-linolenic acid, the plant precursor of fish fatty acids. Fifteen obese people with markers for insulin resistance ate in turn four diets of 4 weeks each: saturated/high fat (SHF), alpha-linolenic acid/low fat (ALF), oleic/low fat (OLF), and SHF. Daily intake of alpha-linolenic acid was 20 g from margarine products based on flax oil. Systemic arterial compliance was calculated from aortic flow velocity and aortic root driving pressure. Plasma lipids, glucose tolerance, and in vitro LDL oxidizability were also measured. Systemic arterial compliance during the first and last SHF periods was 0.42 +/- 0.12 (mean +/- SD) and 0.56 +/- 0.21 units based on milliliters per millimeter of mercury. It rose significantly to 0.78 +/- 0.28 (P < .0001) with ALF; systemic arterial compliance with OLF was 0.62 +/- 0.19, lower than with ALF (P < .05). Mean arterial pressures and results of oral glucose tolerance tests were similar during ALF, OLF, and second SHF; total cholesterol levels were also not significantly different. However, insulin sensitivity and HDL cholesterol diminished and LDL oxidizability increased with ALF. The marked rise in arterial compliance at least with alpha-linolenic acid reflected rapid functional improvement in the systemic arterial circulation despite a rise in LDL oxidizability. Dietary n-3 fatty acids in flax oil thus confer a novel approach to improving arterial function.

Soy isoflavones improve systemic arterial compliance but not plasma lipids in menopausal and perimenopausal women

The possibility that the heightened cardiovascular risk associated with the menopause, which is said to be ameliorated by soybeans, can be reduced with soy isoflavones was tested in 21 women. Although several were perimenopausal, all have been included. A placebo-controlled crossover trial tested the effects of 80-mg daily isoflavones (45 mg genistein) over 5- to 10-week periods. Systemic arterial compliance (arterial elasticity), which declined with age in this group, improved 26% (P < .001) compared with placebo. Arterial pressure and plasma lipids were unaffected. The vasodilatory capacity of the microcirculation was measured in nine women; high acetylcholine-mediated dilation in the forearm vasculature was similar with active and placebo treatments. LDL oxidizability measured in vitro was unchanged. Thus, one important measure of arterial health, systemic arterial compliance, was significantly improved in perimenopausal and menopausal women taking soy isoflavones to about the same extent as is achieved with conventional hormone replacement therapy.

Fundamental movement skills in children and adolescents : review of associated health benefits

The mastery of fundamental movement skills (FMS) has been purported as contributing to children's physical, cognitive and social development and is thought to provide the foundation for an active lifestyle. Commonly developed in childhood and subsequently refined into context- and sport-specific skills, they include locomotor (e.g. running and hopping), manipulative or object control (e.g. catching and throwing) and stability (e.g. balancing and twisting) skills. The rationale for promoting the development of FMS in childhood relies on the existence of evidence on the current or future benefits associated with the acquisition of FMS proficiency. The objective of this systematic review was to examine the relationship between FMS competency and potential health benefits in children and adolescents. Benefits were defined in terms of psychological, physiological and behavioural outcomes that can impact public health. A systematic search of six electronic databases (EMBASE, OVID MEDLINE, PsycINFO, PubMed, Scopus and SportDiscus) was conducted on 22 June 2009. Included studies were cross-sectional, longitudinal or experimental studies involving healthy children or adolescents (aged 3–18 years) that quantitatively analysed the relationship between FMS competency and potential benefits. The search identified 21 articles examining the relationship between FMS competency and eight potential benefits (i.e. global self-concept, perceived physical competence, cardio-respiratory fitness [CRF], muscular fitness, weight status, flexibility, physical activity and reduced sedentary behaviour). We found strong evidence for a positive association between FMS competency and physical activity in children and adolescents. There was also a positive relationship between FMS competency and CRF and an inverse association between FMS competency and weight status. Due to an inadequate number of studies, the relationship between FMS competency and the remaining benefits was classified as uncertain. More longitudinal and intervention research examining the relationship between FMS competency and potential psychological, physiological and behavioural outcomes in children and adolescents is recommended.

Sustaining a hemodialysis exercise program : a review

This article reviews the literature addressing exercise programs for dialysis patients to identify elements necessary for sustaining exercise programs in this population. Literature searches for publications (January 1980–February 2009) in Medline (OVID), PubMed, CINAHL (EBSCO), EBSCOhost EJS, ProQuest Central, Web of Science, Cochrane Library, Google Scholar, ScienceDirect, SpringerLink (Kluwer), and Wiley Interscience (Blackwell) were performed. Reference lists from relevant articles were hand-searched for further publications. Criteria for inclusion included full-text primary research and review articles focused on exercise for adult hemodialysis patients. One hundred and seventy one publications were found with a primary focus on exercise in hemodialysis. Of these, 28 primary research and 14 review articles addressed one or more aspects of sustainability of hemodialysis exercise programs. Factors contributing to sustainable exercise programs included: dedicated exercise professionals; encouragement to exercise intradialytically; dialysis and medical staff commitment; adequate physical requirements of equipment and space; interesting and stimulating; cost implications need to be addressed; exercise is not for everyone; requires individual prescription; and there is no age barrier to exercise on hemodialysis.

Depression and bone mineral density in a community sample of perimenopausal women: Geelong Osteoporosis Study

Objective: Reduced bone mineral density (BMD) in women with a history of depressive disorders has been shown in some, but not all studies. This study investigated the association between self-reported depression and BMD in an age-stratified community sample of perimenopausal women residing in the South-Eastern region of Australia.

Design: Symptoms of depression in the year between July 2000 and July 2001 were ascertained by a self-report questionnaire based on Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV) criteria. Women in the perimenopausal group who had undergone a BMD total hip and spine assessment within the 12-month period after the depression assessment were included in the analysis, resulting in a sample of 78 women aged 45 to 60 years.

Results: In this sample, 14 women were identified as depressed. There was no difference in age, hormone therapy (HT) use, or unadjusted BMD at the total hip or spine between the depressed and nondepressed women (P = 0.14, 0.89, 0.57, and 0.70, respectively), but the depressed women tended to be heavier [depressed (median weight, interquartile range = 80 kg, 66-94) vs nondepressed (72 kg, 61-80) P = 0.06]. Whereas there was no significant difference in age-, HT-, and weight-adjusted BMD at the spine [depressed (mean ± SE = 1.21 ± 0.05) vs nondepressed (1.28 ± 0.03 g/cm2) P = 0.18], adjusted BMD at the total hip for the depressed women was 7.8% lower than for the nondepressed [depressed (mean ± SE = 0.957 ± 0.038) vs nondepressed (1.038 ± 0.023 g/cm2) P = 0.04].

Conclusions: These results suggest that in perimenopausal women, self-reported depression is associated with lower BMD at the hip.

Reliability of isokinetic strength and aerobic power testing for patients with chronic heart failure

PURPOSE: The objective of this study was to assess the reliability of testing skeletal muscle strength and peak aerobic power in a clinical population of patients with chronic heart failure (CHF).

METHODS: Thirty-three patients with CHF (New York Heart Association (NYHA) Functional Class 2.3 ± 0.5; left ventricular ejection fraction 27% ± 7%; age 65 ± 9 years; 28:5 male-female ratio) underwent two identical series of tests (T1 and T2), 1 week apart, for strength and endurance of the muscle groups responsible for knee extension/flexion and elbow extension/flexion. The patients also underwent two graded exercise tests on a bicycle ergometer to measure peak oxygen consumption (VO_2peak). Three months later, 18 of the patients underwent a third test (T3) for each of the measures. Means were compared using MANOVA with repeated measures for strength and endurance, and ANOVA with repeated measures for VO_2peak.

RESULTS: Combining data for all four movement patterns, the expression of strength increased from T1 to T2 by 12% ± 25% (P < .001; intraclass correlation coefficient [ICC] = 0.89). Correspondingly, endurance increased by 13% ± 23% (P = .004; ICC = 0.87). Peak oxygen consumption was not significantly different (16.2 ± 0.8 and 16.1 ± 0.8 mL·kg^-1·min^-1 for T1 and T2, respectively;P = .686; ICC = 0.91). There were no significant differences between T2 and T3 for strength (2% ± 17%;P = .736; ICC = 0.92) or muscle endurance (-1% ± 15%;P = .812; ICC = 0.96), but VO_2peak decreased from 16.7 ± 1.2 to 14.9 ± 0.9 mL·kg^-1·min^-1 (-10% ± 18%;P = .021; ICC = 0.89).

CONCLUSIONS: These data suggest that in a population of patients with CHF, a familiarization trial for skeletal muscle strength testing is necessary. Although familiarization is not required for assessing oxygen consumption as a single measurement, VO_2peak declined markedly in the 3-month period for which these patients were followed. Internal consistency within patients was high for the second and third strength trials and the first and second tests of VO_2peak.

Clinical nurse research consultant : a clinical and academic role to advance practice and the discipline of nursing

Aims:  This article presents a proposal for the Clinical Nurse Research Consultant, a new nursing role. Background:  Although healthcare delivery continues to evolve, nursing has lacked highly specialized clinical and research leadership that, as a primary responsibility, drives evidence-based practice change in collaboration with bedside clinicians. Data sources:  International literature published over the last 25 years in the databases of CINAHL, OVID, Medline Pubmed, Science Direct, Expanded Academic, ESBSCOhost, Scopus and Proquest is cited to create a case for the Clinical Nurse Research Consultant. Discussion:  The Clinical Nurse Research Consultant will address the research/practice gap and assist in facilitating evidence-based clinical practice. To fulfil the responsibilities of this proposed role, the Clinical Nurse Research Consultant must be a doctorally prepared recognized clinical expert, have educational expertise, and possess advanced interpersonal, teamwork and communication skills. This role will enable clinical nurses to maintain and share their clinical expertise, advance practice through research and role model the clinical/research nexus. Implications for nursing:  Critically, the Clinical Nurse Research Consultant must be appointed in a clinical and academic partnership to provide for career progression and role support. Conclusion:  The creation of the Clinical Nurse Research Consultant will advance nursing practice and the discipline of nursing.