Self-reported symptoms of eating disorders amongst university dance students

Eating disturbances are common amongst female athletes, especially those participating in dance. We investigated the prevalence and correlates of eating disorder risk symptoms amongst female student dancers. Fifty-eight female university dancers completed a self-report measure of eating disorders and eating disorder correlates, along with factors hypothesised to be associated with the concept, including perfectionism and anxiety. Height and body mass were measured to calculate body mass index (BMI). Results indicated that psychological variables correlated positively with eating disorder risk, and that BMI and ineffectiveness were correlates best associated with eating disorder risk for these dancers. Results indicated that the screening of dancers using a self-report measure can help to identify dancers suffering from poor psychological health of which one characteristic is disordered eating. Given the implications of well-being and performance, we suggest that future research should investigate factors associated with eating disorders and that course administrators and health practitioners consider these factors when facilitating and optimising the mental health and performance of dancers

Stretch Intensity vs. Inflammation: A Dose-dependent Association?

The intensity of stretching is rarely reported in scientific literature. In this study, we examined the effects of stretching intensities at 30%, 60%, and 90% of maximum range of movement (mROM) on the inflammatory response of the right hamstring muscle. Methods: A randomised within-subject trial was conducted with 11 healthy recreationally active males over a three week period. Participants were strapped into an isokinetic dynamometer in the supine position, with the right knee fastened in a knee immobilizer. After randomising the ROM percentages, the hamstring muscle was moved to one of the three chosen ROM percentages for that week and held there for 5 x 60 seconds followed by a 10 second rest between repetitions. A 5ml blood sample was collected pre-, immediately post, and at 24 hours post intervention for high sensitivity C-reactive protein (hsCRP) assessments. Results: Significant increases in hsCRP levels were observed between 30% mROM and 90% mROM (p=0.004) and 60% mROM and 90% mROM (p=0.034), but not between 30% and 60% (p>0.05). Conclusions: Muscle stretching at submaximal levels does not elicit a significant systemic inflammatory responses

Acute effects of Vitamin D3 supplementation on muscle strength in Judoka athletes: a randomized placebo-controlled, double-blind trial

Objective: Indoor athletes have been shown to be prone to vitamin D3 deficiency. The aim of the study was to examine the acute effects of vitamin D supplementation on muscle function using isokinetic dynamometry. Design: Randomized placebo-controlled, double-blind study. Setting: Institutional. Participants: Adult male white national level judoka athletes (n = 22) who were involved in full-time training. Exclusion criteria were vitamin supplementation, overseas travel to sunny climes, and/or an injury incurred during the last 3 months before testing. Interventions: Subjects were randomly allocated to the treatment (150 000IU vitamin D3) or placebo and given blinded supplements by an independent researcher. Participants were tested twice, 8 days apart, on a Monday morning before the start of judo training and after 2 days of rest. A 5 to 7 mL of blood sample was collected followed by isokinetic concentric quadriceps and hamstring muscle function assessments on the right leg at 30 and 200°·s. Main outcome measures: Repeated-measures analysis of variance was used to analyze isokinetic muscle force and serum 25(OH)D3. Regression to the mean was used to examine changes in 25(OH)D3 levels over the study period. Results: The treatment group demonstrated a significant increase in serum 25(OH)D levels (34%, P ≤ 0.001) and muscle strength (13%, P = 0.01) between days 1 and 8. No significant differences were found for the placebo group for the same period. Conclusions: A single bolus of 150 000IU vitamin D3 had a significant positive effect on serum 25(OH)D levels and muscle function in vitamin D insufficient elite indoor athletes. Clinical relevance: Serum 25(OH)D3 levels of indoor athletes should be monitored throughout the year and especially during winter months. Beneficial responses, in muscle strength and serum 25(OH)D3, to 1 dose of vitamin D3 supplementation can be observed within 1 week of ingestion. Muscle strength is linked to serum 25(OH)D levels. Acute Effects of Vitamin D3 Supplementation on Muscle Strength in Judoka Athletes: A Randomized Placebo-Controlled, Double-Blind Trial (PDF Download Available). Available from: https://www.researchgate.net/publication/283499805_Acute_Effects_of_Vitamin_D3_Supplementation_on_Muscle_Strength_in_Judoka_Athletes_A_Randomized_Placebo-Controlled_Double-Blind_Trial [accessed May 10, 2016]

The Influence of Hormonal Contraception on Vitamin D Supplementation on Serum 25(OH)D3 Status in Premenopausal Women: A Prospective Double-Blind Placebo Random Controlled Trial

Background: A number of cross-sectional studies have highlighted a potential benefit of estrogen-containing contraception on serum 25-hydroxyvitamin D (25(OH)D) levels. The purpose of the present prospective study was to determine whether oral vitamin D3 supplementation significantly increases serum 25(OH)D more for women taking the estrogen-containing oral contraception than those not taking this medication. Methods: Thirty-eight premenopausal adult females aged 18 - 45 years old were recruited from a university campus; exclusion criteria included those presently taking vitamin D supplementation, those who stopped or started taking oral contraception in last 6 months and those taking any other form of contraception. A prospective doubleblind placebo design was implemented; the dependent variable was serum 25(OH)D and the independent variables were using or not using oral estrogen-containing contraception, and vitamin D3 or placebo supplementation. Participants were tested 4 weeks apart, and blood samples were collected using a capillary blood spot sample method and analyzed by liquid chromatography-tandem mass spectrometry. An independent technician prepared the identical supplement bottles with either 100 placebo pills or 100 active vitamin D3 pills (1,000 IU per pill) and participants randomly selected a supplement bottle. Results: Baseline measurements of 25(OH)D were non-significantly 11% higher in those taking estrogen. ANOVA results revealed a significant two-way interaction between supplementation group (treatment vs. placebo) and treatment period (before vs. after) (P < 0.001), demonstrating a substantial rise in serum 25(OH)D for the treatment group compared with the placebo group. The results also identified a three-way interaction (P = 0.014) on serum 25(OH)D between the three independent variables, with the vitamin D oral contraception group having significantly greater serum 25(OH)D increases (from 45.9 to 98.3 nmol/L) compared with those not taking oral contraception (44.2 - 69.6 nmol/L) (P = 0.019). Conclusions: The estrogen-containing oral contraception increases serum 25(OH)D in premenopausal women with a magnified effect in those taking vitamin D supplementation. Future studies need to examine the relationship between estrogen, vitamin D supplementation, serum 25(OH)D, 1,25(OH)D, parathyroid hormone and other markers of bone metabolisms

The Effects of Different Passive Static Stretching Intensities on Recovery from Unaccustomed Eccentric Exercise - A Randomized Controlled Trial

Effects of passive static stretching intensity on recovery from unaccustomed eccentric exercise of right knee extensors was investigated in 30 recreationally active males randomly allocated into three groups: high-intensity (70-80% maximum perceived stretch), low-intensity (30-40% maximum perceived stretch), and control. Both stretching groups performed 3 sets of passive static stretching exercises of 60s each for hamstrings, hip flexors, and quadriceps, over 3 consecutive days, post-unaccustomed eccentric exercise. Muscle function (eccentric and isometric peak torque) and blood biomarkers (CK and CRP) were measured before (baseline) and after (24, 48, and 72h) unaccustomed eccentric exercise. Perceived muscle soreness scores were collected immediately (time 0), and after 24, 48, and 72h post-exercise. Statistical time x condition interactions observed only for eccentric peak torque (p=.008). Magnitude-based inference analyses revealed low-intensity stretching had most likely, very likely, or likely beneficial effects on perceived muscle soreness (48-72h and 0-72h) and eccentric peak torque (baseline-24h and baseline-72h), compared with high-intensity stretching. Compared with control, low-intensity stretching had very likely or likely beneficial effects on perceived muscle soreness (0-24h and 0-72h), eccentric peak torque (baseline-48h and baseline-72h), and isometric peak torque (baseline-72h). High-intensity stretching had likely beneficial effects on eccentric peak torque (baseline-48h), but likely harmful effects eccentric peak torque (baseline-24h) and CK (baseline-48h and baseline-72h), compared with control. Therefore, low-intensity stretching is likely to result in small-to-moderate beneficial effects on perceived muscle soreness and recovery of muscle function post-unaccustomed eccentric exercise, but not markers of muscle damage and inflammation, compared with high-intensity or no stretching.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

BALLET DANCER INJURIES DURING PERFORMANCE AND REHEARSAL ON VARIED DANCE SURFACES

Three dance surfaces regularly used by a professional touring ballet company (n=60) were quantified using standard sports surface testing apparatus. Surface sub-structure construction varied between surfaces and a range of surface force reduction values were reported. Injuries and associated variables occurring within the ballet company were recorded by the company medical staff. An injury was recorded if a dancer experienced an incident that restricted the dancer from performing all activities that were required of them for the period 24hrs after the incident. Injuries were delimited to those occurring in the lower limbs or trunk during reported non-lifting dance activity. Analysis of statistical significance was restricted due to a low injury data sample size. However certain trends in the injury data warrant future research. The surface with the highest variability in intra-surface force reduction was associated with the highest injury rates per week, lower limb injuries per week, mean days lost dancing per injury and likelihood of injury per performance day. Variability in intra-surface force reduction may have a stronger association with injury risk than mean surface force reduction magnitudes

Creative and productive workplaces: a review

The built environment affects our well-being and this in turn influences our effectiveness in the workplace. Poor environments contribute to absenteeism and to people not working as well as they might. This is an enormous cost to the nation. High-quality environmental design is an investment, as occupants are healthier, staff-retention rates are higher, productivity is higher and sustainability ideals are more likely to be met. Workplaces reflect the culture of companies and are places that are not just functional and convenient but give the occupant a wholesome experience in terms of body and spirit

Genetic variation in Wnt/β-catenin and ER signalling pathways in female and male elite dancers and its associations with low bone mineral density: a cross-section and longitudinal study.

The association of genetic polymorphisms with low bone mineral density in elite athletes have not been considered previously. The present study found that bone mass phenotypes in elite and pre-elite dancers are related to genetic variants at the Wnt/β-catenin and ER pathways. Some athletes (e.g. gymnasts, dancers, swimmers) are at increased risk for low bone mineral density (BMD) which, if untreated, can lead to osteoporosis. To investigate the association of genetic polymorphisms in the oestrogen receptor (ER) and the Wnt/β-catenin signalling pathways with low BMD in elite and pre-elite dancers (impact sport athletes). The study included three phases: (1) 151 elite and pre-elite dancers were screened for the presence of low BMD and traditional osteoporosis risk factors (low body weight, menstrual disturbances, low energy availability); (2) a genetic association study was conducted in 151 elite and pre-elite dancers and age- and sex- controls; (3) serum sclerostin was measured in 101 pre-elite dancers and age- and sex-matched controls within a 3-year period. Eighty dancers revealed low BMD: 56.3% had at least one traditional osteoporosis risk factor, whereas 28.6% did not display any risk factor (37.2% revealed traditional osteoporosis risk factors, but had normal BMD). Body weight, menstrual disturbances and energy availability did not fully predict bone mass acquisition. Instead, genetic polymorphisms in the ER and Wnt/β-catenin pathways were found to be risk factors for low BMD in elite dancers. Sclerostin was significantly increased in dancers compared to controls during the 3-year follow-up (p < 0.05)

Bone mineral density in vocational and professional ballet dancers

Summary: According to existing literature, bone health in ballet dancers is controversial. We have verified that, compared to controls, young female and male vocational ballet dancers have lower bone mineral density (BMD) at both impact and non-impact sites, whereas female professional ballet dancers have lower BMD only at non-impact sites. Introduction: The aims of this study were to (a) assess bone mineral density (BMD) in vocational (VBD) and professional (PBD) ballet dancers and (b) investigate its association with body mass (BM), fat mass (FM), lean mass (LM), maturation and menarche. Methods: The total of 152 VBD (13 ± 2.3 years; 112 girls, 40 boys) and 96 controls (14 ± 2.1 years; 56 girls, 40 boys) and 184 PBD (28 ± 8.5 years; 129 females, 55 males) and 160 controls (27 ± 9.5 years; 110 female, 50 males) were assessed at the lumbar spine (LS), femoral neck (FN), forearm and total body by dual-energy X-ray absorptiometry. Maturation and menarche were assessed via questionnaires. Results: VBD revealed lower unadjusted BMD at all anatomical sites compared to controls (p < 0.001); following adjustments for Tanner stage and gynaecological age, female VBD showed similar BMD values at impact sites. However, no factors were found to explain the lower adjusted BMD values in VBD (female and male) at the forearm (non-impact site), nor for the lower adjusted BMD values in male VBD at the FN. Compared to controls, female PBD showed higher unadjusted and adjusted BMD for potential associated factors at the FN (impact site) (p < 0.001) and lower adjusted at the forearm (p < 0.001). Male PBD did not reveal lower BMD than controls at any site. Conclusions: both females and males VBD have lower BMD at impact and non-impact sites compared to control, whereas this is only the case at non-impact site in female PBD. Maturation seems to explain the lower BMD at impact sites in female VBD

Bone mass of female dance students prior to professional dance training: A cross-sectional study

Article Authors Metrics Comments Related Content Abstract Introduction Methods Results Discussion Conclusions Acknowledgments References Reader Comments (0) Media Coverage (0) Figures Abstract Background Professional dancers are at risk of developing low bone mineral density (BMD). However, whether low BMD phenotypes already exist in pre-vocational dance students is relatively unknown. Aim To cross-sectionally assess bone mass parameters in female dance students selected for professional dance training (first year vocational dance students) in relation to aged- and sex-matched controls. Methods 34 female selected for professional dance training (10.9yrs ±0.7) and 30 controls (11.1yrs ±0.5) were examined. Anthropometry, pubertal development (Tanner) and dietary data (3-day food diary) were recorded. BMD and bone mineral content (BMC) at forearm, femur neck (FN) and lumbar spine (LS) were assessed using Dual-Energy X-Ray Absorptiometry. Volumetric densities were estimated by calculating bone mineral apparent density (BMAD). Results Dancers were mainly at Tanner pubertal stage I (vs. stage IV in controls, p<0.001), and demonstrated significantly lower body weight (p<0.001) and height (p<0.01) than controls. Calorie intake was not different between groups, but calcium intake was significantly greater in dancers (p<0.05). Dancers revealed a significantly lower BMC and BMD values at all anatomical sites (p<0.001), and significantly lower BMAD values at the LS and FN (p<0.001). When adjusted for covariates (body weight, height, pubertal development and calcium intake), dance students continued to display a significantly lower BMD and BMAD at the FN (p<0.05; p<0.001) at the forearm (p<0.01). Conclusion Before undergoing professional dance training, first year vocational dance students demonstrated inferior bone mass compared to controls. Longitudinal models are required to assess how bone health-status changes with time throughout professional training