Success is simple things
practiced everyday

Advice and ponderings for swimrunners, swimmers and runners. Where focus goes energy flows.

October 22, 2023 | Tom Jenkinson

Swimming and the Principle of Least Action

Mathematical Laws of Nature – the Principle of Least Action.

In nature, a system will always try to solve a task with the least possible energy… the more you swim the more efficient you get at it…

Four Steps to Faster Swimming (p.29-30 Öppet Vatten) Mikael Rosén:

  1. Frequency – The best way to be a faster swimmer is to have more swim sessions in your training plan. Until you swim 6 times a week it is the most effective way to improve performance.

  2. Flexibility – Make sure your shoulders are not the limiting factor. Two minutes of stretching per day gives results after a year (keep at it).

  3. Speed Variation – use different gears. A swimmer should master at least four levels of intensity.

  4. Finesse – Improve your technique. Get the arms and legs timed with the help of the core. The right technique drills allow the penny to drop. Fly kick stresses the core in a way that is relevant to all swimming.

There are only two mechanistic ways to get faster in swimming: a) take fewer strokes to cover a distance, and/or b) turn over strokes more quickly. The equation to remember: Number of strokes x rate of turnover = time.

We must improve one or both of these factors in order to improve our time. Pay attention to both factors (number of strokes and rate of turnover) when making a stroke change, because they are not always independent of each other. By lowering one factor, you may end up increasing the other factor to the point where the total time is adversely affected.

Increasing distance per stroke has to be done with consideration to the impact on stroke rate/cadence. There is a sweet spot for each individual’s skill level. Much of the success of mastering propulsion comes from paying attention to finer details, such as hand tone, forearm and hand position, upper arm position, and engagement of the core muscles that drive the body over the hand/forearm.

Structuring Swim Workouts

If you are new to structured swim workouts, you might be wondering why we do the things we do. After all, some of you will approach training quite differently. “If I have an hour I just run for an hour!” – So why do we break the swim sessions down into short intervals? Do you really need to hold the rest intervals?

The goal of each session is to maximize the training effect

The training effect is a balance of stress and recovery. Recovery is a part of training, not the absence of it! The target effect differs from session to session but relates to the deliberate training of an energy system. For swimrunners and open-water swimmers, we are looking to develop an efficient aerobic system supported by a decent threshold tolerance and resilient muscular endurance.

To control the intensity, swim sets and rest periods ensure the body (or your ego) does not overexert. For aerobic training, the intensity is (relatively) low, the sets are longer, and the rest periods are shorter. Threshold and strength sets will be shorter, faster/harder, and require more rest.

A secondary training effect is related to the neuromuscular system and skill acquisition. The neuromuscular system is responsible for passing messages to the working muscles, not just to “move the arms in a somewhat circular motion” but on the details – such as hand entry position and other fine neuromuscular adaptations.

Brett Sutton: “One of the most frequent questions asked by athletes and coaches is why in swimming do we gravitate to shorter distance reps done many times? If an Ironman race is 3.8km, why swim 40 x 100m instead of a straight 4km to ‘get the distance? The answer is about technique and the ability of the individual athlete to hold the stroke.”

Water is 830x denser than air

Moving through it effectively and efficiently takes real focus, especially for those who have not learned to a sufficient degree at a young age.

We all have a choice to train with focus/purpose/intention; do I choose to swim up and down with my thoughts elsewhere, or do I control as much of the experience as I can? Every training session is an opportunity for development, but development will be limited and compromised unless you take control of your actions and the process.

Wayne Goldsmith: “Swimming fast is about the swimmer’s capacity to maintain maximum speed, outstanding technique, and brilliant skills. You don’t learn this by swimming a lot of laps at mediocre speeds with terrible technique and awful skills.”

A little quality (hard work) every session

Traditionally, single-sport athletes follow a linear training periodization – focusing on one energy system at a time, at various points of a season, leading into race day. Whereas non-professional open-water swimmers, swimrunners, and triathletes race a variety of distances, with an undefined race season, and have various energy system demands in each race.

Therefore, I like to design sessions to create a mix of stimuli to hit the different energy systems. The overall approach can be termed a spiral system of reverse periodization, spiraling through different intensities by using sets, reps, and rest periods to achieve the desired training effect.

Joel Filliol: “Include some quality in every swim. If you are swimming less than 5x per week, having easy swims is a waste of time. Always include quality, from band to paddles, to sprints, in every swim.”

Mono-speed/mono-stimulus training is suboptimal, each session has a mix of tools (gear) and swim paces. These are there to create a good mix of stresses and each comes with an appropriate recovery interval to optimize the training stimuli.

Respect the rest intervals

Rest periods are matched with the reps, sets, and intensity to facilitate the desired training effect. Are you disciplined with your resting habits? Who among you skips the rest, reduces the rest, or extends the rest?

By having less or no rest, you will compromise your potential development (sabotaging your energy system and neuromuscular adaptations). Likewise, by extending the rest periods you also alter the way the body reacts to the session.

Swim Coaching Tips

  • Forget maximizing meters or laps during swim time. Come to the swim session with a mindset of purposeful practice – it changes everything.

  • Believe in the sessions – there is a deliberate reason the sessions are designed the way they are.

  • Become best friends with the wall clock (not your “Garmin”) and stick to the prescribed rest intervals.

  • Rest with discipline and honesty.

A world-class runner is about 90% mechanically efficient, meaning that 90 of every 100 calories expended produce forward motion, while approximately 10 are lost to heat management, ground friction, wind resistance, etc. Because water is denser than air and highly unstable as a medium for applying power, a world-class swimmer is only 9% mechanically efficient. The typical adult swimmer has an energy efficiency lower than 3% – technique matters even with gear.

The main path to swimming improvement is not simply to make more energy available through maximizing aerobic fitness, it is to waste less energy by improving how you move through the water via skill acquisition.

It is the application of the daily process that is the true differentiator. You have a choice – do you take the easy way or the hard (right) way?

Happy Laps /T.

Acknowledgements. Thanks to Matt Hill (Masters of Tri) for reinforcing and developing many of these ideas. Thanks to Paul Newsome (Swim Smooth) who piqued my deepening interest in swim coaching back in 2015 and put me on the right path.

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