Category Archives: exercise

Why dancers need the perfect balance of strength and flexibility

By Kelsey Jack, PT

My ballet teacher once told me that given a choice between having strength and flexibility, she would choose strength. This has always stuck with me as there is such an emphasis on flexibility within the dance world that often there is a lack of focus on building the strength required to make use of that flexibility. This enhanced focus on flexibility instead of a balance between strength and flexibility creates muscle imbalances. If dancers work to improve their flexibility and ignore balancing the strength around the joints, it leaves the dancer vulnerable to injury.

Why is balancing strength and flexibility important?

Stability is provided to joints from a combination of passive and active structures. Passive structures include the bones that make up the joint and the ligaments that surround it and support it. Active structures are the muscles and tendons that act to both maintain stability and move the joint. Focusing on passive, static stretching, as is often the case in dance, can lead to instability of joints as the ligaments that are meant to stabilize the joint become stretched out and no longer provide joint support.

Flexibility, or range of motion can be divided into two categories: passive and active. Passive range of motion is demonstrated by how high a dancer is able to lift their leg using their hands whereas active range of motion is how high a dancer is able to lift their leg using their hip muscles and is demonstrated by doing a step like a developpé.  Practically speaking, flexibility without strength limits active range of motion and will hinder the height of legs when performing steps that involve controlled movements and sustained positions.

Back bends are a good example of a movement that is common in dance where strength is required to balance the flexibility of the spine. Dancers without good core strength and control will hinge through their spine, relying on one or two segments to gain all of their movement through. This leaves the spine vulnerable to injury as the ligaments and discs are relied on for support. Ideally when doing a back bend the spine should form a “C” curve. Many teachers instruct dancers to breathe up and extend through the top of their head into their back bend to encourage control into this movement pattern. Engagement of the abdominals and stabilizer muscles of the spine are required to move through each segment of the spine in a way that supports the passive structures of the back to create the desired curve.  It is subtle differences such as these in how a dancer moves, using strength to control their flexibility, that improves the quality of movement and decrease the future risk of injury.

Evidence to support strengthening to increase flexibility

As dancers are often concerned about their hip flexibility, a study was done looking into the best way to increase hip active range of motion. The researchers compared three stretching programs over a six week period. The first group of dancers completed a strengthening program where they worked at strengthening their hip flexors at the end of their available range of motion. The second group completed a “light” stretching program for their gluteals, hamstrings, calves, and quadriceps muscles, holding each stretch for 1 minute. This group was asked to perform stretches at an intensity of 3/10 on a scale where 0 is no stretch and 10 is an intense stretch that elicits a burning sensation. The third group performed the same stretches but at a “moderate-high” intensity which was rated as 8/10 on the same scale. The study found that all three groups had an increase in their passive range of motion but only the strength training and the low intensity stretching groups improved their active range of motion. The strengthening group saw the greatest improvements in both passive and active range of motion which is explained by the hamstrings relaxing as the hip flexor is contracted. This allows the hamstring to lengthen while the hip flexor is strengthened. Intense stretching without strengthening (as in the high intensity group) leads to lengthened, weakened muscles which functionally hinder a dancer’s ability to make use of their range of motion. This study demonstrates that exercises that specifically train the hip flexors progress flexibility in a way that translates into dance.

Strengthening allows dancers to maximize their flexibility without compromising the integrity of their passive support structures and increasing their risk of injury. A physiotherapist can assess a dancer’s strength and flexibility and develop a program that will safely allow a dancer to increase their flexibility while strengthening the muscles needed to support their joints, improve performance, and decrease risk of future injury.

BodyTech Physiotherapy

References:

Wyon MA, Smith A, Koutedakis Y. A Comparison of Strength and Stretch Interventions on Active and Passive Ranges of Movement in Dancers: A Randomized Controlled Trial. Journal of Strength and Conditioning Research. 2013. 27(11)3053.

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The Importance of Hydration

Hydration

With increases in temperatures during the summer months, ensuring adequate hydration is extremely important, especially during activities requiring physical exertion.  Every cell and system in the human body relies on water to survive and to work correctly and efficiently, but water is lost every day through sweating, urination and breathing. Sweating is the body’s cooling mechanism, so naturally we sweat more when outdoor temperatures are higher or during exercise. A combination of hot, humid temperatures and physical activity can easily put the body into a state of dehydration. Dehydration decreases the ability of the body to regulate core temperature and decreases blood flow, both of which can have a detrimental impact on exercise performance.

Certain people will be more susceptible to dehydration than others, i.e. children lose water more quickly due to smaller body size, while older adults have difficulty conserving water and have a decreased sensation of thirst. Anyone who works or exercises in hot and humid conditions is also more likely to become dehydrated due to an increased level of sweating. Humidity makes it difficult for sweat to evaporate from your skin, which means it is harder for your body to regulate its temperature and keep cool. Although heavy and prolonged exercise makes people most at risk for dehydration, there is a cumulative effect.  This means with inadequate fluid intake over a few days, even mild or moderate exercise can create a state of dehydration. For athletes, mild dehydration of 1-2% of body weight can decrease the ability of muscles to use glucose, which diminishes aerobic performance and causes fatigue more quickly. Therefore, it is very important to ensure proper hydration in the days leading up to races or games.

How to tell if you are dehydrated:

  • Little urine output and/or urine that is darker than usual
  • Dry mouth, thirst
  • Fatigue
  • Headache
  • Dizziness, lightheadedness
  • Muscle cramps
  • Nausea

Drinking fluids and replacing electrolytes is the easiest and quickest way to treat dehydration. If you have any of the above symptoms and think you may be dehydrated, drink small amounts of water frequently in order to prevent an upset stomach. Sports drinks can also be helpful in treating or preventing dehydration, but take caution as the sugar in sports drinks can cause diarrhea. Eating foods high in water content, such as fruits and vegetables, will help in the rehydration process; and be sure to avoid anything that will continue to dehydrate you further, such as caffeine and alcohol. Severe dehydration will require a trip to the hospital for rapid hydration through an intravenous line. Symptoms of severe dehydration include loss of consciousness, rapid or weak pulse, low blood pressure, and confusion. Untreated severe dehydration can lead to complications, such as heat stroke, and can damage kidneys and muscles. Heat stroke occurs when the body overheats and is no longer able to sweat and cool itself down, usually due to prolonged physical exertion in hot conditions. This is extremely dangerous and requires immediate medical attention, before brain or other organ damage occurs. A milder form and precursor to heat stroke is heat exhaustion, which has symptoms such as heavy sweating, lightheadedness, and muscle cramps. It is very important to treat heat exhaustion before it becomes heat stroke, by moving the person into a cool, shaded area, cooling off with wet towels, and giving liquids if possible. If symptoms continue to worsen, call for emergency medical attention.

How much do you really need to drink?

Although there are many recommendations for how much water to consume, a general rule of thumb is to consistently drink throughout the day, before you feel thirsty. Exercisers will need to consume more than non-exercisers due to water loss through sweating. In the hour or so prior to a workout, try to consume 1-3 cups of water. During exercise, if possible, drink about ½ cup or a few mouthfuls every 15-20 minutes. This will help to prevent dehydration and is especially important if the weather is hot, or the activity is particularly long and strenuous. A handy trick to know how much to drink after finishing a workout, is to weigh yourself before and after. For every pound that you have lost during the activity drink about 3 cups of water. If you weigh the same amount before and after, it likely means you hydrated adequately throughout the activity, and can just continue drinking normally for the rest of the day.

Keeping cool and staying hydrated should be a priority in the hot summer months. Dehydration negatively impacts the body and can lead to a decrease in athletic performance, heat exhaustion or even heat stroke. Drinking water consistently throughout the day, and increasing this amount before and after exercise will help to keep you hydrated and safe during the summer.


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