by Marty Hull
Increasing FlexibilityGreat Breaststroke Kick: The Ins & Outs
Legs are very powerful and efficient on land. In the water, legs don't workas well. Even the best swimmers are able to transfer only a small percentageof their leg power to the water efficiently. Slower swimmers transfer evenless.
How Does Kicking Work?Kicking involves pressing surfaces of the feet against the water at anglesthat will push us forward. Swimmers who have excellent joint range of motionare able to orient the surfaces of their feet so their kicking movementsprovide good propulsion. Swimmers with less joint flexibility produce lesspropulsion from similar movements while exerting equal force. They go slower.
If you improve your joint range of motion, you can:
All of the above can be accomplished safely if you learn about and carefullydo stretching exercises to increase range of motion in the feet, lower legand hips, and supplement these with strengthening exercises to allow faster,more powerful movements. We start with some definitions.
A. Leg Adduction: The drawing to-gether of the legs by contraction of theadductor muscles. A major aspect of the breaststroke kick.
B. Leg Extension: The straightening of the leg at the knee by contraction ofthe quadriceps muscle. The most powerful movement in the body.
C. Medial Rotation of the Leg: The rolling inward of the knee by acontraction of the groin muscles. If the leg is bent at the knee, medialrotation of the upper leg rotates the lower leg and foot out to the side.
D. Lateral Rotation of the Foot: When sitting in a chair with the feet onthe floor, the right foot rotates clockwise around an axis running throughthe knee and the heel. The left foot rotates counterclockwise.
Increased Foot Surface AreaMost swimmers use the surfaces on the inside of the foot and inside of thelower leg to transfer power to the water when doing breaststroke kick. Youcan further increase the useable foot surface area by rolling the outsideedge of the foot over and pushing on the water with the underside of thefoot. To do this, you must be able to roll your foot over.
Stretch 1. To stretch the foot, sit in a chair, grab your foot firmly withboth hands and twist the foot. Apply moderate force forone to one and a half minutes. Stretch both feet two or three times.Gradually increase force levels over a period of several weeks.
To strengthen this movement, forcefully contract the muscles that roll overthe outside edge of the foot. Hold the contraction for three to four secondsand then relax the muscles. Do this 10 to 15 times with each foot. Do thesestretches and strengthening exercises three to five times per week.
Safer KickingButterfly kick and flutter kick are very safe movements. We can do thesekicks as hard as we want to without injury. The breaststroke kick powermovement is a combination of adduction (drawing together) and extension(straightening) of the legs. For most swimmers, the adduction component makesa larger contribution than the extension component. Leg adduction placesgreat stresses on the groin and on the inside of the knee and is the sourceof most injuries in breaststroke. Most swimmers do not have access to aneffective alternative movement so they must use an adduction-basedbreaststroke kick and intuitively control muscle force levels to avoidinjury.
If we change the mechanics of the kick_increasing the leg extensioncomponent and decreasing the adduction component_the breaststroke kickbecomes, in essence, a straightening of the leg. This is a safer and muchmore powerful movement. These changes also allow the foot to move along aslightly longer path. When more force is applied along a greater distance,the result is more distance per kick.
To make these changes, both hip joints must be stretched to allow moremedial rotation.
Stretch 2. Medial rotation: Stand on your left leg. Support yourself withyour left hand. Bend the right leg at the knee and pull the knee forward.Reach the hand over the foot and grasp the instep.
Firmly hold the foot in this position. Look at thispicture very carefully and have someone else compare your position with thepicture so you do the stretch safely and correctly. To stretch, move or pressthe knee back. The farther you move the knee back, the more you will stretchthe area. Maintain pressure for one to 1-1/2 minutes. Uselight pressure at first. After you become familiar with the stretch, use moreforce for longer. Do each leg three to four times per week. Done correctly,this stretch will forcefully rotate the upper leg at the hip joint,increasing hip range of motion without stressing the knee joint.
Strengthening ExercisesTo strengthen this movement, stand on your left foot, bend the right leg atthe knee so the right foot is behind you. Attach a thick piece of surgicaltubing to the wall to your left. Run the tubing behind your left leg and loopit over your right foot. To exercise, keep the rightknee stationary and rotate the upper leg medially. This will rotate the lowerleg and foot counterclockwise against the resistance of the tubing. Exerciseboth legs. Do in sets of 30 to 50 repetitions three to five times per week.As strengthening occurs, increase size of tubing or distance from tubing.
All Solved? Not Yet!The medial rotation of the leg causes the feet to rotate inward. At thisorientation, the foot surfaces no longer effectively engage the water. Moreadjustments are necessary. The lower leg must be stretched to allow the footto rotate out farther. Then it works.
Stretch 3. Lower leg outward rotation: Sit in a chair, reach the right armunder the left leg and then grasp the instep of the foot with the hand, asshown in the pictures. To stretch, press the right elbowforward and pull the right hand back. This causes the foot to rotate outwardand stretches the structures in the lower leg. Stretch each leg for one to1-1/2 minutes three to four times per week.
Caution: This is an extremely powerful stretch. The arm works as a verypowerful lever to rotate the foot. If you push too hard, you may severelydamage your knee, so be very careful.
If you begin with light forces, and carefully increase force levels over aperiod of several months, the knee joint apparatus will gradually strengthen.As this occurs, you will be able to safely increase force. The structures ofthe lower leg will stretch and greater outward foot rotation will bepossible.
Strengthen this outward rotation movement by sitting in a chair with yourfeet on the floor. Forcefully contract the muscles that rotate the feetoutward. Hold the contraction for three to four seconds. Do this 20 to 30times, several times per week.
Now Just Add WaterBegin by doing some breaststroke kicking on your back. When you recover thelegs, keep the knees about an inch apart and do not allow them to break thesurface of the water. This will force you to recover the legs correctly. From this position, rotate the feet outward so theyengage the water. As they engage, begin to straighten the legs (start thekick). As the legs begin to straighten, medially rotate the legs (roll bothknees inward). This causes the feet to sweep out along a longer path. Watchthe kick as you are doing it. Did you do it?
Once you are able to get the feet to sweep out a little wider, try to rollover the outside edge of the foot to engage the water with the bottom of thefoot. If you feel water pressure on the bottom of your foot, you are doing itcorrectly.
After you perfect this drill on your back, try doing some kicking on yourfront. Remember to keep the knees closely together, approximately the samewidth as your hips, and try to get the feet to sweep out wider than theknees. Don't use a kickboard. Use a small, hand sculling movement to supportyour front end. Then try swimming.
These stretches and exercises will eventually allow you to use positions andmovements to which you formerly did not have access. It will take time. Youmay become frustrated. Keep working on the stretches and as range of motionincreases, your movements will gradually begin to change because this is whatyou look for: a more efficient way to swim.
Marty Hull is a top Masters swimmer and a consultant to the StanfordUniversity Swim Team.