When swim experts communicate with athletes about freestyle technique, they usually talk about the things every swimmer should do: maintain a high float, rotate their body, pull with a high elbow and so forth. There is a simple rationale for this emphasis: The freestyle technique of every great swimmer includes these elements. It's impossible to become a great swimmer without them.
Nevertheless, an important fact is obscured by our natural focus on the universal elements of effective freestyle technique: No two great swimmers swim in exactly the same way. Despite all the universals, each top swimmer has a style of freestyle swimming that is unique.
To be sure, the swim strokes of any two professional triathletes are likely to be much more similar than those of any two newbies without a competitive-swimming background. Few if any of the universal elements of effective freestyle technique are natural to beginners, so it makes sense for coaches to concentrate their efforts on removing the idiosyncrasies from the strokes of their beginning athletes and instilling the universals. But because each swimmer is unique, it would be a mistake for any coach to try too hard to make all of his or her swimmers swim exactly alike.
There are certain specific technique variables for which different choices work best for different swimmers. To reach your full potential as a swimmer, you need to train in a way that allows you to find and cultivate these points of individual technique optimization while also mastering the universal elements of good technique. These areas of freedom include stroke rate, kick pattern, arm cycle, recovery style and breathing pattern.
Just as there are some elite pro cyclists who time trial at 85 RPM and others that do so at 100 RPM, there is also a wide degree of variation in the stroke rates that work best for top triathlon swimmers. Shorter athletes with more aerobic power than muscle power tend to swim better with a higher stroke rate. Taller, lankier triathletes with great feel for the water tend to prefer a slower stroke rate.
How do you find the stroke rate that works best for you? First, consistently train to maximize your distance-per-stroke by performing drills to improve your hydrodynamics, using paddles to build a more powerful pull and counting your strokes to objectify your progress. Next, consider using a tempo trainer to test how different stroke rates affect your times in all-out efforts of 100 to 400 yards.
Start by setting the tempo trainer at a tempo that's a little slower than your natural stroke rate. Then move it up to your natural stroke rate and continue increasing it until your times stop improving. (Make sure you're sufficiently recovered for each effort so fatigue does not bias your results.) The stroke rate that results in the fastest times is your optimal stroke rate.
It's a good idea to do this type of test three or four times a year, as changes in your swimming fitness and proficiency may change your optimal stroke rate. Also, understand that your optimal stroke rate is likely to be different at various distances, so be sure to test at longer distances that are more race-specific.
The kick is perhaps the most variable technique element. Some athletes achieve success with a strong, patient two-beat kick. Others find more speed with a fluttering, efficient six-beat kick. A two-beat kick is more common among triathletes, but even within the two-beat tempo there are several possible variations in rhythm.