Wednesday, April 2, 2003 - Physiology
How Long Can You Go? Forward That Is (Part 1 of 6)

- By: Ross McKinnon, PT

The tests and exercises described should be performed with the help of a physiotherapist to achieve maximal benefit.

This article will review and expand upon material previously published on the skifaster.net website last summer and fall. Fast and efficient ski technique requires dynamic flexibility, stability, strength and balance. As a physiotherapist all 4 components are crucial when working with an athlete to both improve performance and recover from an injury. Each individual component is critical to attain optimal overall performance. At a recent ski camp it was pointed out to me that most technique problems we try to correct are related to body position. In other words the inability to achieve a forward body position is the root of most technique problems. For the purpose of this article I will refer to this forward position as the parallel lines of power. The first line of power is the line of the hip, trunk and shoulder the second line is from the ankle to calf. If both lines are parallel at the initiation of the push phase the skier is best able to maximize forward momentum and power. Another way to think of this forward position is chasing your center of gravity down the ski trail.

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(Adapted from NCCP level II Technical Manual)
We constantly talk about hips forward, late kicks and pushing behind in both skating and classic, but how do we correct this? Is the inability to achieve the correct position a result of muscle weakness? A lack of flexibility? Or are they due to compensations in other areas of the musculoskeletal system? The purpose of this article is to describe some physiotherapy tests and subsequent exercises to help an athlete achieve the correct body position during both skate and classic skiing. This requires addressing the following.

FLEXIBILITY
Does the athlete have the dynamic musde length and range of motion to get into good body position without compensating in other areas?
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STABILITY/ MUSCLE RECRUITMENT
Can the athlete control the inner and outer unit muscles during low load movements?
Can the athlete recruit individual muscle groups in the proper order to achieve a forward body position?
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STRENGTH
How strong are the athlete's power muscles to propel them down the ski track?
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SKILL AND BALANCE
Can the athlete apply the previous components with correct technique for maximal power output and efficiency? Does the athlete have the body awareness of where the ideal forward body position is?

Each component is linked and is critical to the final result of improving performance; all four areas must be addressed. It is best to start with a look at the athlete's flexibility.

PART I - FLEXIBILITY

To achieve the above mentioned parallel lines of power a sharp knee and ankle angles are required to initiate the push phase. Ankle flexibility is critical to create the ideal forward body position. Roughly 30-35 of bend at the ankle and knee are required to properly position the body forward during initiation of the push phase. During the diagonal stride 100-105 of hip range of motion is required from maximal hip flexion to hip extension (Note: this is not a pure hip flexion range as it also includes rotation in the pelvis, spine and hips). If for example a skier has only 10 of hip extension and lacks 30 of hamstring flexibility essentially the skier is working with only 70 of range of motion at the hips. In order to achieve a lengthened stride the skier will be forced to compensate elsewhere. The body will take the path of least resistance during movement, most likely in the sacroiliac joint region or lumbar spine. Inappropriate motion will be transferred to the site of greatest relative flexibility and is termed the area of 'give'. This may result in cumulative micro trauma, subsequent injury, and further muscle imbalance.

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(Adapted from NCCP level II Technical Manual)

Due to a number of factors including overuse, posture, poor stability and muscle weakness certain muscles can become tight and short. Muscle length has to be considered on an individual basis as each body type will demonstrate varying degree of tightness. The 'normal' values physiotherapists use are listed in the testing, but are only guidelines to be used. Dynamic flexibility is extremely important as the greater the length a muscle can travel before beginning to stiffen the less the body will have to compensate elsewhere in the kinetic chain.

MODIFIED THOMAS TEST

Test procedure:
The athlete sits at the edge of a table holding onto both knees. The athlete rolls onto their back keeping the knees bent. With the thoracic spine and pelvis on the table the athlete pulls one knee up to their chest until the lumbar spine flattens.
The opposite leg (the leg to betested) is positioned with the hip and knee flexed to 90. The tester lowers the test leg to the table by extending the hip. Avoid allowing the leg to deviate away from the body, bending the non-test leg up to far, excessively flexing the spine or allowing the spine to extend off the table.

Normal: Thigh rests on the table with the knee flexed to 90 in the midline. Individual muscle tightness can be differentiated with the following tests.
Shortened Rectus Femoris: Extending the knee allows the hip to lower closer to the table.
Shortened Iliotibial band/Tensor Fascia Lata: Abducting the thigh away from the midline allows the thigh to lower closer to the table. (Most common tightness)
Shortened Iliopsoas: The hip remains above the table with both knee extension and hip abduction.

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(Redrawn from Kendall 1993)

HAMSTRINGS
Test procedure:The athlete lays on their back with the spine and pelvis in neutral alignment. Both legs are extended. With one hand the tester monitors the position of the spine and pelvis while lifting the leg with the other hand until resistance is felt. It is critical to keep the knee straight, not rotate the hip or allow the pelvis or spine to arch.

Normal: Ideally the knee should straighten to 80.

Shortened Hamstrings: The legs extends less than 80

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(Redrawn from Kendall 1993)

LATS/ PECS FLEXIBILITY
Test procedure:
The athlete lies on their back maintaining a neutral spine position, both knees are bent. The athlete raises their arms above their head trying to contact the floor. Do not allow the spine to extend or arch away from the floor.

Normal: The athlete's arms should contact the floor without excessive scapular movement.

Shortened Lats Dorsi/Pectoralis: Arms do not reach floor with back keeping neutral spine position.

Tightness of Rotator cuff Muscles: Excessive movement of the scapula around the chest wall (protraction).

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HEELCORD FLEXIBILITY
Test Procedure- Start by placing a straight ruler on the floor against a wall. The athlete should face the wall with the tip of the big toe 10cm away from the wall, the foot must be pointing straight ahead. Make sure that if the athlete overpronates (i.e. flattens the arch) that they maintain an arch and do not let the foot flatten any further. The athlete then bends the knee directly forwards keeping their knee over the 2 and 3rd toes until the knee touches the wall. If the knee then touches the wall move the foot back 2cm and repeat. Determine how far away the ankle can bend without lifting the heel, flattening the foot or letting the knee go to the inside.

Normal: This test only allows for comparison from side to side, you cannot compare measurements to other individuals. An athlete should be able to achieve 20 of pure ankle bending. This test is a great way to measure improvement in ankle range of motion.

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(From APTEI 2001)

PIRIFORMIS
The athlete should lay on their back with both legs extended. The tester then flexes the leg to be tested until the hip is at a 90 angle. The tester then adducts the hip (brings the leg across the body towards the other leg) until resistance is felt. Make sure the pelvis and back do not move during this. Then externally rotate the leg by bringing the heel towards the athletes shoulder.

Normal: The athlete should be able to achieve 45 of external rotation

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(Redrawn from Kinetic Control 2000)

RECTUS FEMORIS PRONE
The athlete positions themselves facedown on the floor or table. The athlete must keep their spine in neutral alignment and not allow the spine to extend or rotate. The tester then passively flexes the knee towards the buttocks until there is resistance in the rectus femoris muscle or the spine begins to extend or rotate.

Normal: the knee should flex to 120.

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RECTUS ABDOMINUS
The athlete positions themselves facedown on the floor or table. The athlete then fully exhales any air and does not breathe in again. The athlete then pushes up on the hands or elbows to the point of full spinal extension. The athlete is then instructed to take a deep breath in to fully expand the ribcage. Note any difficulty with expansion of the

ribcage, 'hinging' of the spine or tightness in the rectus abdominus.
Normal: the athlete should be able to achieve full rib cage expansion in full spinal extension.

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HIP ADDUCTORS
The athletes should lie on their back with both legs extended. The athlete should bend one knee to a 45 angle and lower it to the side. Make sure that there is no pelvic rotation or hip hiking.
Normal: the athlete should be able to achieve 45-50 of lowering.

Shortness: The athlete will feel a stretch in the inner thigh if tight.

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Don't worry at this point about trying to stretch the shortened muscles you find. In Part II we will review the tests of stability system. The tests of stability will identify the areas of 'give' and lack of muscular control. It is critical to lengthen the tight and short power/mover muscles while maintaining control of the 'give'. If the 'give' is not first stabilized, trying to stretch tight and short muscles is ineffective. The body will move though the 'give' prior to the area that truly needs lengthening.

Ross McKinnon is a former ski racer now working as a physiotherapist at Rutland Physical Therapy in Kelowna, BC. His interests include improving an athlete's performance through the use of specific exercise. For further questions he can be contacted at or at . Ross provides individual evaluations to help improve performance and prevent injury.

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