The following is an extract from “Dance Scottish” Magazine.
Sabita Stewart, a researcher at Glasgow Caledonian University Division of Physiotherapy, carried out a study in collaboration with Glasgow Branch into the effects of SCD on bone health. Here is her report.
Background : Osteoporosis is a condition in which bone strength is reduced because of a change in bone quality and a reduction in the amount of bone material present. It is thought to affect 1 in 3 (postmenopausal) women and 1 in 12 older men. It is often called the ‘silent killer’ because it may not be diagnosed until one or more bones are broken. There are 20,000 osteoporotic fractures every year in Scotland and the bones most commonly broken are wrist, spine and hip. Following a hip fracture one third of people do not regain their former independence. The personal costs, in terms of finance and well-being, are immeasurable, affecting not only the individual, but also family, friends, neighbours, work and leisure.
Studies have shown that fractures can be prevented by improving bone strength and avoiding falls. To improve and maintain bone strength, current guidelines recommend that low to medium impact exercise, such as stepping, marching or intermittent jogging, is more appropriate for individuals over 50 (Chartered Society of Physiotherapy. 1999). In the Glasgow area there are 15 physiotherapist-led exercise classes a week which are specifically for individuals diagnosed with, or at risk of developing osteoporosis. These classes, which cater for approximately 450 people a year, incorporate exercises such as stepping, march and sidestepping to provide the recommended impact forces.
How much impact force is enough? A large well conducted study undertaken in Germany (Kemmler et al,2004) used 50 postmenopausal women and showed that activities which generate impact forces between 1.5 and 2.5 times bodyweight could offset bone loss.
It has been suggested that certain forms of dance, including Scottish country dancing (SCD) may provide similar impact forces and therefore also be good for bone health. Latest figures provided by the Royal Scottish Country Dance Society show that there are 3,700 registered members in Scotland dancing each week as well as an unknown number of unregistered individuals dancing with both affiliated and unaffiliated groups.
Scottish country dance study : There has been very little research on different types of dance that could provide suitable impact forces to improve and maintain bone health. A study to evaluate SCD focusing on the pas de bas step was undertaken at Glasgow Caledonian University in 2008. The pas de bas step was compared to marching and side-stepping, two of the exercise included in physiotherapist led exercise classes. To recruit volunteers, adverts were placed in RSCDS Glasgow Branch newsletters and one Glasgow club was visited. Twenty one ladies each made a single visit to Glasgow Caledonian University where they walked, marched and sidestepped over a force plate set in the floor of the movement laboratory.
The force plate measures the forces produced as each foot strikes the plate and from this, the vertical forces reflected back into the legs and therefore the lower limb bones, can be calculated. The group who took part in the study had an average age of 65 years (ranging from 55 to 82).
Results : On average, the pas de bas step generated forces almost twice body weight through the lower limbs. This was shown to be significantly higher forces than generated during walking, side-stepping or marching. Walking and side-stepping generated similar levels of forces whilst forces recorded during marching were higher.
Implications : From this study, we have shown that the levels of force generated during the pas de bas step are higher than those recorded for walking, side stepping and marching. Therefore, as pas de bas step generated almost twice bodyweight, it would appear to be a good exercise to offset bone loss. It would be sensible to propose Scottish country dance should now be added to the list of recommended activities for women who wish to maintain bone health. In addition, the pas de bas step could be a valuable addition to the physiotherapy led exercise classes.