MAXIMUM HEIGHT OF A DANCE JUMP IN DIFFERENT JAZZ SHOES

Jumping is a key skill in dance and the effect of different dance shoes on jump performance is not known. Female pre-professional and professional dancers (n=14) were recruited to perform consecutive maximum vertical jumps in second position in four types of jazz shoes and barefoot, with and without music. An overall effect of the jazz shoes was found both with and without music (

1000 Norms Project: Protocol of a cross-sectional study cataloging human variation

Background Clinical decision-making regarding diagnosis and management largely depends on comparison with healthy or ‘normal’ values. Physiotherapists and researchers therefore need access to robust patient-centred outcome measures and appropriate reference values. However there is a lack of high-quality reference data for many clinical measures. The aim of the 1000 Norms Project is to generate a freely accessible database of musculoskeletal and neurological reference values representative of the healthy population across the lifespan. Methods/design In 2012 the 1000 Norms Project Consortium defined the concept of ‘normal’, established a sampling strategy and selected measures based on clinical significance, psychometric properties and the need for reference data. Musculoskeletal and neurological items tapping the constructs of dexterity, balance, ambulation, joint range of motion, strength and power, endurance and motor planning will be collected in this cross-sectional study. Standardised questionnaires will evaluate quality of life, physical activity, and musculoskeletal health. Saliva DNA will be analysed for the ACTN3 genotype (‘gene for speed’). A volunteer cohort of 1000 participants aged 3 to 100 years will be recruited according to a set of self-reported health criteria. Descriptive statistics will be generated, creating tables of mean values and standard deviations stratified for age and gender. Quantile regression equations will be used to generate age charts and age-specific centile values. Discussion This project will be a powerful resource to assist physiotherapists and clinicians across all areas of healthcare to diagnose pathology, track disease progression and evaluate treatment response. This reference dataset will also contribute to the development of robust patient-centred clinical trial outcome measures

The Effect of Jazz Shoes on Dance Performance

The effect of jazz shoes on dance performance Despite dancers performing up to 200 jumps per class, the effect of dance shoes on jump performance has not previously been explored. Sautés are a two-legged dance jump used as a foundation for more complex jumps. The aims of this thesis were to explore the impact attenuation properties of jazz shoes and their effect on sauté height, landing and takeoff technique, and impact attenuation. A systematic review of the literature was undertaken to examine the impact attenuation effect of conventional shoes compared to barefoot during weight-bearing activities (Chapter 2). Few studies investigated the effect of shoes on jump landings, with no studies investigating dance shoes. Mechanical impact testing of four different jazz shoe designs was performed to determine their impact attenuation properties. The newest jazz sneaker design was the most impact attenuating jazz shoe despite another design having a thicker sole. 3D motion analysis of dancers performing a series of eight sautés in the different shoes with and without music was undertaken. Jump height was reduced in the high-heeled shoes compared to all other shoe conditions with a subsequent increase in stance time to synchronise with the music (Chapter 3). Knee flexion was greater in high-heeled shoes, and ankle flexion was greater in all jazz shoes than barefoot. Conversely, midfoot and MPJ motion was reduced by all jazz shoe designs (Chapter 4). Knee joint stiffness was reduced in high heeled shoes and both sneaker designs compared to barefoot (Chapter 5). The jazz shoes reduced midfoot joint velocity thus restricting midfoot joint power, with the opposite effect at the ankle during both landing and propulsive phases (Chapter 6). The jazz shoes tested in this thesis altered lower limb motion, with larger kinematic and kinetic changes displayed in the Chorus shoes resulting in a subsequent decrease in jump height. Future research should assess dance shoe design in terms of both function and aesthetic performance