The dancer as a performing athlete: physiological considerations.

The physical demands placed on dancers from current choreography and performance schedules make their physiology and fitness just as important as skill development. However, even at the height of their professional careers, dancers' aerobic power, muscular strength, muscular balance, bone and joint integrity are the 'Achilles heels' of the dance-only selection and training system. This partly reflects the unfounded view, shared by sections of the dance world, that any exercise training that is not directly related to dance would diminish dancers' aesthetic appearances. Given that performing dance itself elicits only limited stimuli for positive fitness adaptations, it is not surprising that professional dancers often demonstrate values similar to those obtained from healthy sedentary individuals of comparable age in key fitness-related parameters. In contrast, recent data on male and female dancers revealed that supplementary exercise training can lead to improvements of such fitness parameters and reduce incidents of dance injuries, without interfering with key artistic and aesthetic requirements. It seems, however, that strict selection and training regimens have succeeded in transforming dance to an activity practised by individuals who have selectively developed different flexibility characteristics compared with athletes. Bodyweight targets are normally met by low energy intakes, with female dance students and professional ballerinas reported to consume below 70% and 80% of the recommended daily allowance of energy intake, respectively, while the female athlete 'triad' of disordered eating, amenorrhoea and osteoporosis is now well recognised and is seen just as commonly in dancers.An awareness of these factors will assist dancers and their teachers to improve training techniques, to employ effective injury prevention strategies and to determine better physical conditioning. However, any change in the traditional training regimes must be approached cautiously to ensure that the aesthetic content of the dance is not affected by new training techniques. Since physiological aspects of performing dance have been viewed primarily in the context of ballet, further scientific research on all forms of dance is required

The Effect of Strength and Plyometric Training on Functional Dance Performance in Elite Ballet and Modern Dancers

Background: Ballet and modern dance are both art forms that require technique, artistry, grace and precision. Both dance forms require a degree of strength and muscular endurance for optimal performance. It is not known what value strength or plyometric training may have on functional dance performance. Objective: To systematically review the effects of strength and/or plyometric training on functional dance performance in elite ballet and modern dancers. Methods: A systematic review of literature indexed in the following databases: Medline, CINAHL, SportsDiscus, Physiotherapy Evidence Database (PEDro) and PubMed was conducted. The quality of the studies was graded using the PEDro Scale. Results: Eight studies satisfied the eligibility criteria and were included in this review. The studies\u27 population age range was 19?27?years. Methodological scores based on the PEDro scale were 4 to 6 out of 10. All of the included studies (100%) scored 4 out of 10 or higher on the PEDro scale. Strength training resulted in significant improvements in jump height (P? Conclusion: Moderate evidence indicates that supplementary strength training interventions via traditional resistance training or whole-body vibration methods and plyometric training interventions may increase certain dance-performance measures such as jump height and general aesthetic facility without changing certain anthropometric measures in elite ballet and modern dancers

Body-size phenotypes and cardiometabolic risk in Rheumatoid Arthritis

Objectives: Obesity is a significant contributor to metabolic complications. However, such complications are not uniform in people with similar body-size. The existence of normal-weight individuals with and obese individuals without metabolic complications has been described in the general population and is important in the context of cardiovascular disease (CVD). This has not been investigated in rheumatoid arthritis (RA), a condition associated with increased cardiometabolic risk. This study aims to identify the prevalence and predictors of body-size phenotypes in RA and investigate their associations with CVD risk. Methods: Body mass index (BMI: kg/m2), body fat (BF) and fat free mass (FFM), RA characteristics and CVD risk factors were assessed in 363 (262 females) volunteers with RA. Abnormal cardiometabolic status was defined as the presence of >1 of the following: hypertension, increased triglycerides or increased Low or reduced High Density Lipoprotein, high glucose, insulin resistance. Results: Among normal-weight, overweight, and obese participants 25%, 45.8%, 57.1% respectively were metabolically abnormal. Old age (B= 1.032, err=0.011; p= 0.005), waist circumference (B= 1.057, err= 0.011; p= 0.000), and smoking cessation (B= 1.425, err= 0.169; p=0.036) were significant predictors for metabolic abnormality. Conclusions: A significant number of RA patients present with different body-size and metabolic phenotypes. BMI alone is not a sufficient indicator of cardiometabolic risk in RA; this may have significant implications in their CVD risk evaluation. Body fat distribution seems to be a significant contributor to such abnormalities. Further research is needed, focusing on the metabolic properties of specific adipose depots of RA patient

Fitness in contemporary dance: a systematic review.

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

Methodological considerations for documenting the energy demand of dance activity: a review.

Previous research has explored the intensity of dance class, rehearsal, and performance and attempted to document the body's physiological adaptation to these activities. Dance activity is frequently described as: complex, diverse, non-steady state, intermittent, of moderate to high intensity, and with notable differences between training and performance intensities and durations. Many limitations are noted in the methodologies of previous studies creating barriers to consensual conclusion. The present study therefore aims to examine the previous body of literature and in doing so, seeks to highlight important methodological considerations for future research in this area to strengthen our knowledge base. Four recommendations are made for future research. Firstly, research should continue to be dance genre specific, with detailed accounts of technical and stylistic elements of the movement vocabulary examined given wherever possible. Secondly, a greater breadth of performance repertoire, within and between genres, needs to be closely examined. Thirdly, a greater focus on threshold measurements is recommended due to the documented complex interplay between aerobic and anaerobic energy systems. Lastly, it is important for research to begin to combine temporal data relating to work and rest periods with real-time measurement of metabolic data in work and rest, in order to be able to quantify demand more accurately

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

Chronic eccentric exercise and antioxidant supplementation: effects on lipid profile and insulin sensitivity

Eccentric exercise has been shown to exert beneficial effects in both lipid profile and insulin sensitivity. Antioxidant supplementation during chronic exercise is controversial as it may prevent the physiological training-induced adaptations. The aim of this study was to investigate: 1) the minimum duration of the eccentric exercise training required before changes on metabolic parameters are observed and 2) whether antioxidant supplementation during training would interfere with these adaptations. Sixteen young healthy men were randomized into the Vit group (1 g of vitamin C and 400 IU vitamin E daily) and the placebo (PL) group. Subjects received the supplementation for 9 weeks. During weeks 5-9 all participants went through an eccentric exercise training protocol consisting of two exercise sessions (5 sets of 15 eccentric maximal voluntary contractions) per week. Plasma triglycerides (TG), total cholesterol (TC), high density lipoprotein (HDL), low density lipoprotein (LDL), apolipoproteins (Apo A1, Apo B and Lpa) and insulin sensitivity (HOMA) were assessed before the supplementation (week 0), at weeks 5, 6, 7, 8 and 9. TG, TC and LDL were significantly lower compared to pre supplementation at both weeks 8 and 9 (P<0.05) in both groups. HDL was significantly elevated after 4 weeks of training (p < 0.005) in both groups. There was no effect of the antioxidant supplementation in any of the variables. There was no effect of either the training or the supplementation protocol in apolipoproteins levels and insulin sensitivity. A minimum duration of 3 weeks of eccentric exercise training is required before beneficial effects in lipid profile can be observed in healthy young men. Concomitant antioxidant supplementation does not interfere with the training-induced adaptations

Prevalence and risk factors of dance injury during COVID-19: a cross-sectional study from university students in China

© (2021) The Authors. Published by Frontiers Media. This is an open access article available under a Creative Commons licence. The published version can be accessed at the following link on the publisher’s website: https://doi.org/10.3389/fpsyg.2021.759413Objectives: Although COVID-19 has transformed dancers’ training environment worldwide, little is known on how this has affected injury prevalence, causes and risk factors. Methods: An online investigation was conducted (September to November 2020) involving Chinese full-time dance students, which covered two 6-month periods just before and during the first COVID-19 lockdown. Results: 2086 students (19 ±2.4yrs) responded. Injury prevalence before lockdown dropped from 39.6% to 16.5% during lockdown (p<0.01). A significant increase in injury severity during lockdown was noted with a 4.1% increase in moderate to severe injuries (p<0.05). During the lockdown, injuries of the lower back, feet and shoulders decreased significantly (p<0.01), but the knees, ankles and groin/hip-joint injuries remained the same. Recurrence of old injury and fatigue remained as the top 2 perceived causes of injury between the two periods with unsuitable floor (p<0.01), cold environment (p<0.05) and set/props (p<0.05) increasing. Students’ fatigue degree decreased (p<0.01) and sleep hours increased (p<0.01) during lockdown. Binary logistic regression analysis indicated that dance injury was associated with fatigue, hours of sleep, and action taken if they suspected an injury during lockdown (p<0.05), but was only related to time set aside for cool-down and age before lockdown (p<0.05). Conclusion: Although the injury prevalence dropped significantly during the first COVID-19 lockdown in Chinese dance students, the main dance injury characteristics remained the same. Decreased fatigue and longer sleep hours could explain the aforementioned drop in injury prevalence during the lockdown.This work was supported by the China Scholarship Council for their financial contribution (D.Y