These are questions frequently asked at our clinics with Dr. Havriluk's answers.

How do swimmers with obvious technique problems still swim very fast?

Fast swimming is determined by a number of factors - physiological, psychological, biomechanical, etc. A swimmer may be so gifted in one attribute (e.g. strength, lung function, pain tolerance) that it offsets his/her technique limitations. A swimmer with a high maximum oxygen uptake (75 ml/kg/min) or a high peak hand force (60 lbs) can have substantial technique limitations and still swim very fast.

Which fast swimmer has perfect technique?

Faster swimmers have more effective technique than slower swimmers. (See Havriluk, 2003) However, even the fastest swimmers have limiting factors. (See Havriluk, 2006a) If you copy the technique of an Olympian, you risk adopting their limiting factors as well as their positive technique elements.

What about the __________(characteristic technique element) of __________(Olympic champion)?
A characteristic technique element of an Olympian may be obvious, but not necessarily helping him/her swim faster. It's vital to differentiate between characteristic technique and effective technique, especially in Olympians.

What is the most important factor in swimming propulsion?
Hand force is the single most important factor in swimming propulsion. It is directly related to swimming speed. If you increase your hand force, you will swim faster. (See Havriluk, 2004)

How do you increase hand force?

Most swimmers can increase hand force by increasing the hand speed throughout the stroke cycle. Bilateral symmetry is necessary to maximize hand force. (See Havriluk, 2007b) Avoiding wasted motion and force losses will also increase the average force on each stroke. (See Havriluk, 2006a)

How do hand force values vary within a stroke cycle?
The arm can move into stronger and stronger positions at faster and faster speeds throughout the stroke cycle. Hand force peaks about halfway into the push phase (after the arm passes the shoulders) for freestyle, butterfly and backstroke. For a swimmer with effective technique, the force value on the push phase is typically twice as much as on the pull phase. (See Havriluk, 2009, in press)

What is the most important part of the freestyle stroke?
The entire stroke cycle is important. Most swimmers don't take full advantage of the push phase because the arm exits prematurely. Maintaining the elbow below the surface can increase the force and time of the push. A swimmer who does not double the force from the pull to the push has a major technique limitation. (See Havriluk, 2009, in press)

What causes shoulder injuries?

Three contributing factors to shoulder injuries are: overuse (excessive training distance), ineffective technique, and inadequate strength training. Any single factor can cause injury, but a combination is often responsible. A decrease in training distance, a change in technique to decrease stress on the shoulder, and strength training that targets muscular imbalances are all necessary to recover from a shoulder injury. (See Becker & Havriluk, 2006 and Stroke Test)

Can hip rotation increase hand force in freestyle?

No. In freestyle, the torso rotates about the polar axis (a reference axis through the center of the body from head to feet). Summation of forces (See Francis, 2007, Chapter 4) requires that successive body segments (torso, upper arm, lower arm, hand) rotate in the same direction (as in throwing). The freestyle arm motion is perpendicular to the torso rotation and the hand force cannot be increased by the force of hip rotation. Although the timing of the push phase in freestyle is usually simultaneous with torso rotation, rotating the hips harder or faster will not increase hand force. Prins (2007) described how exaggerated torso rotation is even associated with counterproductive motions.

When is gliding recommended?

It is appropriate to glide when the body is moving faster than swimming speed. For example, when the body enters the water after a start or leaves the wall after a turn, it is moving faster than swimming speed and gliding is appropriate. There is one other time when gliding may be appropriate. During breaststroke, for a fraction of a second after the kick, the body may be moving faster than swimming speed. When this is the case, it is counterproductive to immediately begin the arm motion.

Is there a glide phase in freestyle?

No. Gliding in freestyle (usually associated with "catch-up stroke") is counterproductive. During a glide phase, there is no propulsion from either hand. The body slows down and requires considerable energy to speed up. The energy cost of speeding up on every stroke is greater than maintaining a relatively constant speed. Gliding in freestyle is biomechanically ineffective, physiologically inefficient, and anatomically stressful. (See Counsilman, 1955 and  Havriluk, 2007, page 5)

What is the most important factor in swimming resistance?

Reducing the body cross-section (the area perpendicular to the direction of body motion) is the most important factor in swimming resistance. Keeping the hips and legs directly behind the shoulders minimizes the cross-section. (See Havriluk, 2005)

What's the best measure of swimming technique?

Counting strokes is the easiest way to measure technique, but not the best. A decrease in stroke count does not always indicate a more effective technique. An increase in stroke count does not always indicate a less effective technique. The active drag coefficient is the most accurate measure of swimming technique. (See Havriluk, 2003; Havriluk, 2006b; and Havriluk, 2007a)

What's the best way to control technique changes?
Skills must be learned at a slow swimming speed. Once a swimmer has learned to control his/her movements at a slow speed, gradually increasing the stroke rate will help a swimmer maintain control at faster speeds. Individual instructional sessions and regular analysis sessions expedite the learning process. (See Havriluk, 2006b and Havriluk, 2007c)

Is the head completely submerged in freestyle?

No. One of the many misconceptions about swimming technique is that the head must be submerged for the legs to stay behind the shoulders and minimize resistance. A more effective way to minimize the body cross-section is to arch the lower back to bring the heels to the surface. Maintaining the water level just above the hairline puts the head in an optimal nonbreathing position that also minimizes the head motion necessary to breathe. (See Havriluk, 2009)

As the elbow flexes at the beginning of the freestyle pull, does the forearm become vertical?

If the elbow is flexed and the forearm is vertical, the hand must be lateral (to the outside of) the shoulder. As force is applied during this motion, torque is generated and the body twists about the antero-posterior (front to back) axis. The twisting increases resistance and slows swimming velocity. It is more effective to diagonally orient the forearm during the pull phase, so that the hand passes beneath the head. The swimmer will benefit from the improved mechanical advantage of the elbow angle and have the arm in a stronger position to generate force on the push phase.

Do hand paddles cause shoulder injuries?

While it's possible for paddles to cause an overload on the shoulder joint, it is far more likely that an ineffective technique is to blame for a shoulder injury. For example, if the arm entry on freestyle is parallel to the surface, the arm is in a weak and awkward position that can stress the shoulder when the pull begins. Swimmers often continue torso rotation after the entry is complete, which further stresses the shoulder. If additional stress is added with paddles, the combination of these three factors is equivalent to a "perfect storm" for the shoulder.

Should I stop wearing hand paddles if I have a shoulder injury?

If hand paddles cause shoulder pain, it is advisable to stop wearing them during conditioning. Paddles can serve a very important purpose, however, during technique work. Paddles slow the hand speed and make it easier to track the hand path that is within the swimmer's field of view. Paddles also make the orientation of the hand on entry and exit more obvious. The enhanced feedback is vital to improving technique to overcome the injury.

Can hand paddles improve technique?

In spite of advertising claims, improving technique is far more complicated than just wearing a piece of plastic on your hands. There is no research that supports an improvement in technique by simply training with a specific paddle design. The paddle goes where the hand takes it, not the other way around. The strength training benefit of paddle design, however, has been documented.

Why don't swimmers get more technique instruction during team practices?

If you do the math, it's easy to understand why there's not more time for instruction during a team practice. On a typical team, a coach will have 30 swimmers for a 2 hour workout. If only 30 minutes of the coach's time is taken up by explaining sets, fixing goggles, checking performance times, etc, he/she has 90 minutes left. If the coach uses all of the remaining 90 minutes for technique instruction, each swimmer gets 3 minutes of individual attention per workout. On the average, 3 minutes is only enough time for a coach to evaluate and interact with a swimmer about a single technique element.