Why Dancers May Be At Risk for Stress Fractures and Osteoporosis

"Movement is life. Life is a process. Improve the quality of the process and you improve the quality of life itself." – Moshe Feldenkrais

            Dancers exercise daily. They are constantly on their feet.  They jump, they turn and they constantly apply additional stress to their bones.  The skeleton knows how to respond to this stress, it grows, or models, more bone to support it.  However, studies of ballet dancers have found that they are at risk for stress fractures and that their bone mass measurements, or bone mineral density scores, are equal to or below that of their inactive peers.  How can this be true?  Why isn’t the body doing its job?

            The answer is that the body can only do its job or respond properly if it’s given the right tools and cues.

            Dancers tend to be thin and even underweight.  Less weight means there is less stress put on the bones on a daily basis.  Therefore, even though classes and rehearsals include weight-bearing exercises, the stress on the skeleton is still less than it would be for someone who falls into the ideal or average weight bracket.

            Dancers are known to restrict the amount of food they eat.  There is a constant pressure in the dance community to eat less and look thinner.  Additionally, dancers spend an enormous amount of time doing physical activity.  Large amounts of physical activity burn large amounts of calories.  When that factor is combined with a low or restricted caloric intake, the body is burning more fuel than it is receiving and an energy deficit is created.  Research has linked energy deficits to lower bone mineral density values.

            Restricting food can also lead to diets that are low in nutritional value and high in caffeine.  Diets lacking in nutritional value tend to be low in calcium, which is necessary for bone growth and development.  When you add that caffeine interferes with the body’s ability to absorb calcium, a recipe for a calcium deficit is created.

            Moreover, studies have shown that poor diets can lead to disruptions in the reproductive system.  Research has shown that female dancers go through adolescence and get their first period, or menarche, later than their peers.  This delay in adolescence means there are lower levels of estrogen in the body, and estrogen plays a big role in making sure that the body can absorb the calcium that is eaten.

            Since it is important for the body to create and “stock up” on as much bone as possible during the teen years to avoid fragile bones, it is easy to see why dancers might be at risk for developing osteoporosis.  The good news is that dancers, when armed with some knowledge, can change that.

            Additional weight-bearing exercises can be added to a dancer’s life - weight training and walking can easily be added into a training schedule.  Knowing how to properly fuel the body is important for everyone, but it is especially important for dancers and athletes.  Our next post will help you figure out how to do just that!

•             Don’t forget to subscribe to our email list (on the right)!  The Healthy Dancer will only use it to send you our blog posts!
•              Like us on Facebook too!

Dancers & Bone Health

“The harder the demand placed upon the structure, the stronger the foundation must be.” Our bones – they protect our organs, they manufacture red blood cells, they store calcium, they provide a place for muscles to connect, they permit movement and they provide the framework for our bodies.  Without our skeletal system, we could not exist, yet we rarely think about how our bones develop or bone health. Although our bones appear sedentary, bone tissue is very active and each week 5-7% of our bone mass is recycled, or remodeled.  The outer surface of our bones is compact bone, which is composed of a web of proteins that hardens into a tough structure.  The inside of our skeletons is made of spongy bones with spaces in between the bone cells. Our bones grow from the outside in.  Specialized cells called osteoblasts build bone by travelling to the surface of the bones and depositing collagen molecules between the structural cells to form a matrix and that hardens into layers of compact bone. Meanwhile, other cells called osteoclasts resorb, or breakdown, the mineralized matrix from the inside.  The bottom most layer is dissolved and calcium is released into the bloodstream. This process serves to renew our bones and occurs in a balanced manner most of the time.  During growth spurts, and especially during adolescence, the creation, or modeling, of new bone occurs in addition to the remodeling process, resulting in a surplus of new bone. It is also important to know that osteoblasts (the builders) respond to increased loads that are placed upon the bones such as weight training or weight bearing activities like walking, running and jumping.  When the body recognizes an increased load, or stress, on the skeleton, the osteoblasts are called in for overtime and begin to model more new bone to protect the body against the increased strain. Bone cells grow old like any other cells, and, unfortunately, osteoblasts (the builders) age quicker than the osteoclasts (the dissolvers).  Between the ages of 30 and 40, the osteoblasts begin to slow down while the osteoclasts continue to resorb bone tissue.  A deficit of bone mass is naturally created which can lead to osteoporosis.  People with osteoporosis have brittle, fragile bones which can fracture easily. The best defense against osteoporosis is encouraging the body to create as much bone mass as possible during the formative years and to stimulate the osteoblasts with weight bearing physical activity. Since dance is a weight bearing activity, it would seem that dancers have nothing to worry about, right?  Next week’s post will explain why dancers have to be concerned.