This week, while updating my personal practice log on the Favorite Practices and Sets conference of the TI Discussion Forum, a short thread titled Surprising Discovery caught my eye. The poster had written “I recently noticed how fast I am with one-arm crawl, in which one arm is constantly in front, the other crawling. I timed myself and found this: 50m normal crawl, all out: 40s; 50m one-arm crawl: 50s (changing sides every 8th pull)”

I saw in this an opportunity for a followup to my recent post A TI Primer: The Why and How of Drills to illuminate the process we follow when dropping certain drills and choosing/designing others. Our process for doing is characterized by an unusual degree of rigor.

Traditional Single-Arm

The ‘one-arm crawl’ he describes should be quite familiar to anyone who has swum a workout directed by a non-TI coach. Single-arm, with the opposite arm forward, is among the most commonly-used of freestyle drills.  We used this drill in our first swim camps, in 1989 and 1990. I was intimately familiar with it from my days as a coach of competitive swimmers 1972-88.

At those early camps—as I always had–I taught single-arm with close attention to form and feeling. Like current TI drills, I instructed swimmers to cycle through a series of focal points while practicing it. I also had them compare their right- and left-arm strokes by calculating 25y/m Swim Golf scores (strokes + seconds) for each.

We stopped using single-arm crawl in the early 90s because it no longer matched our evolving technique priorities. In fact, it directly violated them.

We’ve long been guided by the dictum that “The shape of the vessel matters more than the size of the engine.” In other words, reducing drag matters more than increasing propulsive power.

The one-arm crawl, in which you leave the non-stroking arm forward, violates that principle in three ways:

  1. The swimmer focuses on pushing water back with the arm.
  2. By starting the push-back in a flat-on-the breast position, there is no opportunity to use weight shift as the source of power. Instead you rely wholly on fatigue-prone arm and shoulder muscles.
  3. It emphasizes steady flutter kicking–and can easily become a kicking exercise.

In TI, we believe that all stroke drills should imprint the same skills and habits as prevail in the whole-stroke you are seeking to develop.

These include:

  1. Use available forces (gravity, buoyancy and body mass) to generate power before using muscular forces. In freestyle and backstroke, this occurs through weight shift. There is no weight shift in the drill you’re doing.
  2. Use powerful and fatigue-resistant larger muscle groups–particularly the core–before smaller and fatigue-prone muscles, like the arm and shoulder.
  3. In the case of the Catch-and-Press (which single-arm purports to develop), focus on Holding Your Place rather than on Pushing Water Back. Single-arm does the opposite.

Single-SIDE vs. Single-ARM

Our 2.0 Freestyle Mastery Self Coaching Course teaches a Single-Side drill–as opposed to Single-Arm. In TI Freestyle, we strive to swim with the WHOLE BODY, not the arms and legs. This means we teach a core-driven stroke, which observes and promotes the three technique principles I list above.

You do Single-Side Freestyle with the non-stroking arm at your side (hand in ‘Cargo Pocket’ as in our Torpedo drill). When the other arm is forward, it impedes rotation, forcing you to use arm/shoulder muscles to create propulsion. The series of pix illustrate Right-Side Freestyle.

Begin in your best Skate position. In this position, the hand and arm are angled down, facing back, in the ideal position to trap water. In Single Arm- both arms are at the surface, facing down, at the start of the drill, and the swimmer is flat on the breast, rather than slightly rotated as I am here.

1.2 R UnGlovUW1

Strive to Hold Your Place with the right arm, as the left hip—aided by gravity begins to drive down—and the right foot is poised to drive down, lifting right hip toward the surface. In single-arm the left arm, being forward, impedes the ability of the left hip to drive down. And the feet flutter non-stop.

1.2 R UnGlovUW2

The weight shift and stroke are complete. The body has moved past the place where the hand was at the start. The left hip and right foot are down—as they would be in the whole-stroke version of a TI freestyle with a 2-Beat Kick.

1.2 R UnGlovUW3


After right-hand recovery I’m still balanced and aligned on my left side as my right hand comes through the Mail Slot. My right hip and left foot will drive together to return me to my starting position as in the first photo.

1.2 R UnGlovUW4

Our Single-Side drill–Lesson 1, Drill 2–in our Freestyle Mastery series, imprints a balanced and sleekly-shaped vessel (Pic 1), an effective catch, that moves you forward instead of moving the water around (Pic 2); propulsion that’s driven by the whole body (Pic 3), and great body control (Pic 4). Everything you could ask of a stroke drill.

Learn this and more principles-based skill-building drills in our 1.0 and 2.0 Freestyle Self-Coaching Courses.