Service Spotlight: How to Do a Swim Analysis

Here at CBCG, every new athlete gets a free swim analysis included with their coaching subscription, and we update that swim analysis each year at our CBCG Bonanza, held each December in Portland (with other locations around the country coming soon!). Why is getting a swim analysis so important that we make that the first thing we do with a new athlete? Well, swimming is more like golf in terms of technical requirements than cycling or running. So many things need to happen at the same time for you to move in an alien orientation (horizontal) through an alien medium (water). Our swim analyses look at you from each pertinent angle, letting you know where you’re doing things correctly and where you could make some improvements. We’ll roll through our six angles in order below, and you can watch, above, as I go through an analysis of one of our athletes.

Angle One: Side View Above Water

This is usually the most flattering angle, so we tend to start here. When we look at a swimmer from the side, we’re watching the following aspects:

  1. If the swimmer lifts the head to breathe

  2. How the breath is timed to the stroke (early breath/late breath)

  3. How the arm is recovered over the water and how it enters the water (want to read an entire POST about this subject? You can do that here)

  4. We also watch for the rhythm of the stroke. Some athletes look like they’re trying to attack the water, flailing down the lane. Others are very “polite” and probably take too few strokes, thinking that fast swimming is about trying to disturb as little water as possible.

Angle Two: Side View Below Water

This is usually the least flattering angle to swimmers, since it reveals what odd things their bodies are doing underwater. When we look at a swimmer from the side below the surface, we’re tracking these qualities:

  1. If their legs sink behind them

  2. How much/how little they kick

  3. The quality of their catch (from hand entry until the arm is directly below the shoulder) and pull-through (from end of catch to hand exit)

  4. Where they look in the water

We tend to really focus on the quality of the catch, here, since that is going to have the biggest impact on other aspects of the stroke, in particular if the swimmer has sinky legs. Usually those sinky legs are a result of a so-so catch and pull-through, so if we can fix that issue of propulsion, then the legs tend to correct as well.

Angle Three: Top View

The top-down angle reveals many other crucial aspects of the swimmer’s stroke. Here, we are looking for the following qualities of the stroke:

  1. Do the swimmer’s hands cross an imaginary centerline, drawn through the spine, out in front of his or her body? If so, this is going to ramify down through the body, usually leading to a swimmer snaking down the pool (or swimming off course in open water). A crossover in front often leads to our next issue…

  2. A scissor kick. Created when the swimmer rotates too much or creates instability at the front of the stroke by crossing over. You can see this happening when a swimmer’s legs spread apart behind them in a wide “V.” A scissor kick is essentially deploying a parachute behind you, so fixing this issue is crucial.

  3. Breath timing. Top down gives us another chance to watch the swimmer’s timing of the breath vis-a-vis the stroke. We want the swimmer to finish her breath before her hand passes her face above the water (on its way towards re-entry). If the swimmer isn’t doing this, it’s a clue that they’re not getting enough air out while their face is under water.

  4. General lack of movement. You’re supposed to rotate along a long axis while doing freestyle, which means your spine, hips, and shoulders should be aligned, and there should be a relative lack of movement as they rotate.

Angle Four/five: 3/4 view front

When we watch from the 3/4 front angle, above water and below, we’re watching to see the swimmer’s breathing patterns. From above the water, we’re looking for the mystical bow wave. What’s a bow wave? Well, OK, some nautical terminology, here. If you’ve ever seen a boat move through the ocean or a lake, it makes a little pile of water right at its prow. That pile of water has to go somewhere, so it flows “downhill,” creating a small trough right behind the boat’s nose. Here’s a good example:


You can see that depression, right behind the bulge of water out in front of the boat, right? Well, we make that, too, as long as we keep our heads still as we swim forward. That trough is a really nice place for us to breathe into, as there’s air there that we don’t have to lift our head for. So when looking at the swimmer above the surface, we look to see if they are making that bow wave AND making use of the trough behind it. When we go underwater, we look to see if the swimmer is holding his/her breath. In the video above, you can see our swimmer isn’t creating a bow wave (or is making a very small one), and therefore having to lift her head to breathe. And when we go underwater, you can see that she’s not exhaling regularly—we should see a steady stream of bubbles coming out of her mouth while underwater. Instead, you can see that her mouth is slightly open, with no bubbles. This swimmer is holding her breath, and making it much more difficult on herself! As yourself this: would you ever hold your breath while running?

Angle Six: Front

And our final angle: directly in front of the athlete. Here’s what we’re looking for:

  1. Is the angle of the swimmer’s arm, measured from the elbow, between 100-120 degrees? This should result in the swimmer’s hand being about 2-2.5 feet below their body and directly under the shoulder.

  2. The hand should not sweep under the body (the dreaded “s-curve,” taught in the 1980s and 1990s to swimmers such as Yours Truly.

  3. The swimmer should rotate in a 90 degree arc, from 45-50 degrees to the horizontal of the pool floor, to 45-50 degrees on the other side. Anything more than that is over-rotation and will cause breathing and stroke timing issues. Anything less than that is under-rotation, and will cause issues of not being able to recover the arm properly over the surface of the water.


So that’s “it.” We get it—there’s a lot there to think about! Swimming really is very technical, and you shouldn’t be daunted by the amount of information above. Improving at swimming takes a long time, and is more akin to improving at golf than cycling or running—you simply must put in the practice time AND the fitness time. If you just get in the water and do drills, you’ll never build your fitness to a place where you can actually get through a practice without falling apart and watching your form suffer. If you never work on your technique, you won’t progress much in terms of speed. You’ll become more enduring, which is good, too, but speed gains will elude you.

We offer 1-2-1 video analysis here at CBCG, and if it’s something you think might benefit you, you can contact us about it here!