Balance performance of undergraduate dancers: an evaluation of current and novel approaches in balance testing and training in theatrical dance

Abstract

Balance skills are considered essential for dancers as they are required to perform complex, virtuoso movements. However, there is a dearth of evidence on the appropriateness of existing balance tests and training protocols for dancers. The aims of this thesis were to: (a) test sequentially the assumptions of associations between different field balance tests and between dancers’ balance ability and their dance performance, followed by an examination of the relevance of sports functional balance tests on dancers and, building on the first aim, (b) develop a reliable, dance-specific balance scoring tool and testing protocol examining the effects of balance training in a randomised controlled trial. Study 1 assessed associations between five field balance tests: Star Excursion Balance Test (SEBT), the modified Romberg test, the Airplane test, the BioSway Balance System (Biodex, USA) and a dance-specific pirouette test. Results showed strongest relationships between some (SEBT) reach directions (p<0.01), but very weak to moderate relationships between some balance tests including some SEBT directions, Romberg, Airplane, Biosway, and pirouette (p<0.01 and p<0.05). Study 2 assessed associations between balance ability and dance performance comparing the five field tests from Study 1 to the same participants’ technique and repertoire performance scores in ballet, contemporary, and jazz genres. Results showed a low predictive association of balance ability on dance performance (p<0.01 and p<0.05). The first two studies demonstrated low predictive association between field tests and between balance ability and dance performance, suggesting limitations in the sensitivity of the tests for the dance population. Thus, studies 3 and 4 used a more functional tool to assess its sensitivity towards balance ability of the undergraduate population. Study 3 examined the effects of potential bilateral differences on dynamic postural stability during single-leg landing using a time to stabilisation protocol. Asymmetric training has been suggested in the literature but results showed that bilateral differences did not correlate with dancers’ balance ability; no significant differences were found in dynamic postural stability between the right and left leg and poor effect size was noted. Next, Study 4 examined the effects of fatigue using the same time to stabilisation protocol as Study 3. Fatigue has been associated with injury levels in dancers and balance ability in pre-professional dancers. Results showed that a fatigue condition (Dance Aerobic Fitness Test) had no significant effect on dancers’ postural stability or bilateral differences. Similar to the earlier studies, the functional test protocols in these two studies were limited to basic movements for dancers and lacked the sensitivity to measure variable postural control adaptations. Building on the findings of the first four studies, Study 5 developed a novel Accumulation Balance Score designed to gather data on postural stability and control in a variety of dance-specific settings. Results showed excellent interrater (ICC=0.963) and intrarater (0.992) reliability. Study 6 examined the effects of balance training on postural stability in a randomised trial. To capture postural control data, the Accumulation Balance Score was applied to the data. Results showed effects of training on some balance tasks: time (p=0.048), distance (p=0.004), and in various balances: arms (p=.014), legs (p=.016 and p=.001 and p=.042), and spine (p=.041 and p=.018). Post hoc tests revealed mixed findings between groups. Collectively, the results in this thesis revealed that current balance testing and training may not be functionally relevant for dancers with expertise in organising and patterning balance strategies. In contrast, aspects of novel dance-specific balance training may challenge dancers’ entrained responses, and the reliable Accumulation Balance Score can be applied to more novel approaches and protocols in assessing balance, more closely replicating embodied dance experience with ecological validity. For the first time, postural stability and postural control can be measured together in a balance assessment.