RESUMEN
BACKGROUND: The use of vitamin D supplementation has increased due to greater recognition of widespread deficiency. AIMS: There has been little research on the effectiveness of different delivery methods and therefore the aim of was to test the efficacy of different delivery methods on serum 25(OH)D. METHODS: Using a randomised repeated measures double-blind placebo design (registered under ClinicalTrials.gov Identifier no. NCT03463642), changes in serum 25(OH)D over a 4-week period using a capillary spot method were monitored. 62 female participants blindly chose a number related to a supplementation delivery method: pill placebo, pill, oral liquid, oral liquid placebo, Skin oil application (SOA) placebo, SOA plus vitamin D3 suspension, or SOA plus vitamin D3 suspension with essential oil enhancer; active vitamin D supplements contained 100,000IU. Participants took their allocated supplements over a 24-hr period with serum 25(OH)D retested 4 weeks later. Liquid chromatography-tandem mass spectrometry method was applied to dried blood spot samples by an independent laboratory. RESULTS: ANCOVA reported a significant difference between the groups (F1,6 = 146.68; p < 0.001, eta2 = 0.51). Separate analysis within the delivery methods (pill, SOA, oral liquid) indicated significant differences between the active and placebo supplementation groups (p < 0.01). Post hoc analysis of absolute changes indicated vit D pill and SOA + vit D + essential oil had significant increases (p < 0.05) in serum 25(OH)D compared to all other interventions with no significant difference between them. CONCLUSIONS: In human participants vitamin D oral pill has the greatest effect on serum 25(OH)D levels. Skin oil application delivery of vitamin D using a penetrator enhancer has also been shown to be an effective method of delivery.
Asunto(s)
Suplementos Dietéticos , Formas de Dosificación , Vitamina D/análogos & derivados , Vitamina D/administración & dosificación , Vitaminas/administración & dosificación , Administración Oral , Administración Tópica , Adulto , Método Doble Ciego , Femenino , Voluntarios Sanos , Humanos , Piel , Vitamina D/sangre , Población Blanca , Adulto JovenRESUMEN
It is unclear whether the modern ballet body stereotype of long limbs is advantageous in dance performance. Therefore, we investigated the relationship between leg-length and selected dance movements representative of power, dexterity, and range of motion in ballet dancers at different competence levels. METHODS: The total of 10 recreational, 24 vocational, and 10 professional ballerinas volunteered. They were subjected to: a) lower limb-length measurements, b) power tests (vertical jump-sautés and unilateral countermovement jump-temps levé), c) dexterity tests (tendus and double battement frappes), and d) flexibility tests (lateral active and passive-développé à la seconde). RESULTS: For power, regression analyses revealed negative leg-length relationships in recreational dancers (p<0.05) and positive leg-length relationships in vocational dancers (p<0.05). We also found negative relationships between leg-length and dexterity in the vocational group (p=0.01). No significant predictions of leg-length on power, dexterity, and range of motion were found in professional dancers. Multiple comparisons revealed significant differences between groups only for dexterity (p<0.01) and range of motion (p<0.01). CONCLUSION: Based on selected movements representative of power, dexterity, and range of motion, the present exploratory data indicate that lower limb length is not a determinative criterion for ballet success. Further studies should investigate whether body stereotypes, such as long limbs, are linked to dance injuries.
Asunto(s)
Baile/fisiología , Extremidad Inferior/fisiología , Rango del Movimiento Articular , Adolescente , Antropometría , Imagen Corporal , Femenino , Humanos , Músculo Esquelético/fisiología , Equilibrio Postural/fisiología , Percepción Social , Adulto JovenRESUMEN
Video analysis has become a useful tool in the preparation for sport performance and its use has highlighted the different physiological demands of seemingly similar sports and playing positions. The aim of the current study was to examine the performance differences between classical ballet and contemporary dance. In total 93 dance performances (48 ballet and 45 contemporary) were analysed for exercise intensity, changes in direction and specific discrete skills (e. g., jumps, lifts). Results revealed significant differences between the 2 dance forms for exercise intensity (p<0.001), changes in direction (p<0.001) and discrete skills (p<0.05) with gender differences noted in the latter (p<0.05). Ballet was characterised by longer periods at rest (38 s x min(-1)) and high to very high exercise intensities (9 s x min(-1)), whilst contemporary dance featured more continuous moderate exercise intensities (27 s x min(-1)). These differences have implications on the energy systems utilised during performance with ballet potentially stressing the anaerobic system more than contemporary dance. The observed high rates in the discrete skills in ballet (5 jumps x min(-1); 2 lifts x min(-1)) can cause local muscular damage, particularly in relatively weaker individuals. In conclusion, classical ballet and contemporary dance performances are as significantly different in the underlying physical demands placed on their performers as the artistic aspects of the choreography.
Asunto(s)
Rendimiento Atlético/fisiología , Baile/fisiología , Ejercicio Físico/fisiología , Grabación en Video , Femenino , Humanos , Masculino , Músculo Esquelético/metabolismo , Factores Sexuales , Estudios de Tiempo y MovimientoRESUMEN
Joint hypermobility is defined as an excessive range of motion. Although the dance profession has often promoted hypermobility for aesthetic reasons, there is a belief amongst health professionals that potential risks associated with the condition may have been overlooked. The aims of this review were to examine the epidemiology of joint hypermobility in dancers; the effects on fatigue and bone health; the injury profile of hypermobile dancers; and the use of the Beighton score as a diagnostic tool. Depending on the criteria used, epidemiological studies suggest that hypermobility among dancers can be as high as 44%, especially in students. As hypermobility has been linked to fatigue in the general population, the hypermobile dancer should be careful given the association between fatigue and aetiology of injury in dance. Similarly, in light of research encouraging dancers to become fitter, this recommendation may not be appropriate for hypermobile dancers. In addition, the Beighton score used in most dance related studies may not be an appropriate measure of hypermobility in these populations. More research is necessary into this area to ascertain the reasons for the attrition rate from student to soloist/principal level and whether it is linked to dance health and injury issues.
Asunto(s)
Baile , Fatiga/etiología , Inestabilidad de la Articulación/etiología , Huesos/metabolismo , Huesos/patología , Fatiga/epidemiología , Humanos , Inestabilidad de la Articulación/complicaciones , Inestabilidad de la Articulación/epidemiología , Rango del Movimiento ArticularRESUMEN
Functional ankle instability (FAI) is a common condition following ankle injury characterised by increased risk of injury. Ankle sprains are a common acute form of injury suffered in dancing and loss of balance can affect not only risk of injury risk but also performance aesthetics. Whole body vibration training (WBVT) is a new rehabilitation method that has been linked with improving balance and muscle function. 38 female dancers with self reported unilateral FAI were randomly assigned in 2 groups: WBVT and control. Absolute centre of mass (COM) distribution during single leg stance, SEBT normalised research distances and Peroneus longus mean power frequency (f(med)) where measured pre and post 6-week intervention. There was a significant improvement in COM distribution over the 6 weeks from 1.05 ± 0.57 to 0.33 ± 0.42 cm² (P<0.05), and 4 of the 8 planes of direction in the SEBT Ant, Antlat, Med and Antmed from 77.5 ± 7.1 to 84.1 ± 5.8% (P<0.05) compared to control groups during the course of the 6 week training intervention. There was no evidence of improvement in peroneus longus (f(med)) over time (P=0.915) in either group. WBVT improved static balance and SEBT scores amongst dancers exhibiting ankle instability but did not affect peroneus longus muscle fatigue.
Asunto(s)
Terapia por Ejercicio/métodos , Inestabilidad de la Articulación/terapia , Esguinces y Distensiones/terapia , Vibración , Adolescente , Articulación del Tobillo/patología , Baile , Femenino , Humanos , Fatiga Muscular , Músculo Esquelético/metabolismo , Factores de Tiempo , Adulto JovenRESUMEN
We investigated the associations between leg length and specific ballet movements in different skill groups. Volunteers were from an undergraduate dance programme (n=18), a pre-professional school (n=43) and from an elite classical ballet company (n=45). Individual data were collected for anthropometry, vertical jump, leg dexterity, and leg active and passive ROM. ANCOVA identified both main effects as significant with regard to vertical jump (gender P<0.001 and skill P=0.017); leg length was also identified as a significant covariate (P=0.023). Analysis of leg dexterity identified no significant effects with gender, skill or leg length. Active and passive range of motion noted gender (P=0.001) and skill (P<0.001) differences. Leg length was found to be negatively associated with both active and passive ROM (P=0.002). In conclusion, the present data highlight the diverse and conflicting effects of leg length on fundamental ballet skills. The longer legs that benefit vertical jump have a negative influence on range of motion and leg dexterity except for highly skilled dancers, who through skill, seem to have overcome the effects of some of these dichotomies.
Asunto(s)
Baile/fisiología , Pierna/anatomía & histología , Rango del Movimiento Articular/fisiología , Adolescente , Adulto , Análisis de Varianza , Antropometría , Femenino , Humanos , Masculino , Factores Sexuales , Adulto JovenRESUMEN
It has been suggested that dancers are less fit compared to other athletes. However, the majority of studies make their arguments based on data deriving mainly from ballet. Therefore, the aim of the current review was to investigate: a) aerobic and anaerobic fitness, muscular strength and body composition characteristics in contemporary dancers of different levels, and b) whether supplementary exercise interventions, in addition to normal dance training, further improves contemporary dance performance. Three databases (Medline, Cochrane and the Cumulative Index to Nursing & Allied Health research database) were searched to identify publications regarding the main fitness components of contemporary professional and student dancers. At a professional level, it appears that contemporary dancers demonstrate higher maximal oxygen uptake and higher scores in muscular endurance than ballet dancers. However, contemporary dance students are equally fit compared to their ballet counterparts and their body composition is also very similar. Only two studies have investigated the effects of supplementary exercise training on aspects of dance performance. Further research is needed in order to confirm preliminary data, which suggest that the implementation of additional fitness training is beneficial for contemporary dance students to achieve a better performance outcome.