Using Coupling Energy for a Faster Freestyle

By Gary Hall Sr. | Nov. 20, 2019, 3:31 p.m. (ET)

swimmer in pool

Coupling motions in freestyle may be the most powerful swimming technique that you’ve likely never heard of. A coupling motion is a movement that you do with a part of your body that generates no propulsion by itself, but adds to the propulsion of your kick and pull. An excellent example of a coupling motion is the swinging of your arms while walking or running.

In freestyle, there are two principle coupling motions, body rotation and arm recovery. The two are linked — if you do one particularly well, you automatically get some of the other. Using a strong finish for your arm recovery may be the only BOGO technique in the sport of swimming.

I. Body Rotation

Let’s start with body rotation.  Of the two coupling motions, body rotation is potentially more powerful than arm recovery. There is simply more mass in your body than in your arm. The amount of kinetic energy you can generate from your body rotating or your arm recovering over the water is related to their mass, their radius (length of the arm, width of the body), and their angular velocity (speed of the body rotation or arm recovery). It is important to recognize that the last two factors are exponentially related to the energy produced.

The Race Club uses Pressure Meter technology. Pressure Meter technology measures the pressure on the front and back of the pulling hand. It also measures the angle and speed of the body rotation (angular velocity). Using this technology, we have gathered some new information about body rotation and how it affects your hand propulsion.

First, body rotation does not occur all at the same time. There are two critical components to body rotation, the shoulders and the hips. The peak rotational velocity in the shoulders occurs just after the recovering hand enters the water, and the peak rotational velocity of the hips occurs about two tenths of a second later. The pulling hand is typically near the shoulder when the shoulder rotation peaks (depending on the freestyle technique used). The pulling hand is at the very end of the pulling motion (or releasing) when the hip rotation peaks. Depending on where and when you emphasize the speed of body rotation, using your shoulders or hips will often determine where you get the most propulsion in your underwater pull. Your peak pulling force could be in front of the shoulder, past the shoulder, or at the very end of the pull.

Hip-driven Freestyle Technique
A hip-driven freestyle technique has a slower stroke rate of 55-70 arm strokes per minute, so the hands are held out in front longer. Using this technique, you will want to maximize your propulsion from each stroke because chances are pretty good that you don’t have a strong freestyle kick. To increase your pulling propulsion, you’ll want to increase coupling energy from your shoulders and your hips. The best ways to do that are accelerating your recovering hand speed at entry (the end of your arm recovery), and pushing the hand hard out the back (rotating the hips at the same time). At the end of the pull, the hand needs to keep pushing backward, not upward. You do not want to be splashing water over to the next lane as your hand releases on the recovery—that is wasted energy.

II. Arm Recovery

Driving the hand down hard to the water on the recovering arm is the BOGO I was referring to. By doing so, you will automatically increase the speed of your shoulder rotation, increasing the propulsion from your pulling hand at that moment. This requires a little more thought and practice—nothing occurs automatically here. At The Race Club, we have developed several useful drills that will help you improve this technique. We can also demonstrate how to increase your kicking propulsion, which will serve your hip-driven freestyle technique well.

Shoulder-driven Technique
For those swimmers that prefer a shoulder-driven, faster-stroke-rate freestyle (80-100 arm strokes per minute), there simply isn’t time to push your hand out the back nor rotate your hips aggressively. Concentrate on using a more vertical arm recovery (rather than swinging the recovering arm to the side) and driving your hands hard to the water. The low, swinging-type arm recovery means that you will rotate your body less, minimizing the coupling effect. Using a vertical arm recovery and driving the hand down hard—piercing the surface of the water—you will maximize the coupling energy of your rotating shoulders for the pulling arm. To keep the stroke rate up, you’ll need to release the hand earlier at the end of the pull.

Hybrid Technique
Hybrid freestylers use a hip-driven technique on one arm and a shoulder-driven technique on the other (like Phelps, Ladecky, Lochte, and many others). They usually have stroke rates somewhere in the middle (70-90 arm strokes per minute) and depend greatly on using both their shoulders and hips for coupling energy. With this technique, the recovering arm speed is asymmetrical — the recovering arm comes down faster on the breath side than it does on the non-breath side.

Catch-up Freestyle Technique
For those of you using a catch-up freestyle technique, where one hand remains in front until the recovering arm strikes the water, it is a bad idea. It may be suitable for some drills, but that technique loses all of the coupling effects of shoulder rotation on your pulling arm. I haven’t seen anyone using a catch-up freestyle technique win any races yet.

Whichever acceptable freestyle technique you choose to use, hip-driven, shoulder-driven, or hybrid, you will benefit from the two important coupling motions of body rotation and arm recovery speed, either from the shoulders, hips or both.

Have you decided what freestyle technique works best for you?  If not, let's help you figure that out.  We are just a phone call away!

Yours in swimming,
Gary Sr.


Gary Hall Sr., M.D. is a three-time Olympic swimmer (‘68, ‘72, ‘76) who earned a medal in each of the three Olympic Games. At one time he held 10 world records in all strokes except breaststroke and was the World Swimmer of the year in 1969 and 1970.

The views expressed in this article are the opinion of the author and not necessarily the practices of USA Triathlon. Before starting any new diet or exercise program, you should check with your physician and/or coach.