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Updated: Jul 16, 2020

1. Definition:

Pacing is the distribution of energy use during exercise. The goal of pacing, which is almost certainly a fundamental quality of exercise, is to achieve the desired outcome without fatigue interfering with the completion of the task or with the person’s basic health.

Pacing can also be a powerful competitive tool, allowing athletes to disrupt the performance of their competitors and achieve victory(1)

There is good evidence that pacing can be learned (2), can be practised and can have a profound impact on performance.

2. Swimming and pacing:

Due to the highly resistive properties of water, pacing is arguably more critical in swimming than in many other sports.

Swimming is mechanically inefficient, because only 6 to 18 per cent of the energy created from metabolism is actually converted into the muscles doing gainful work(4).

The more fatigued the swimmer becomes, the greater technique deterioration becomes. This further increases drag and results in an increased metabolic energy cost and an even greater rate of fatigue.

Clearly, technique and physiology have to be very much in tune in swimming, and pacing strategy has a massive impact on both of these areas.

An extensive analysis of international competition lap times has revealed that races are often won in the middle portions, in which gaps open up that cannot then be closed(5)

4. Key Factors in Determining a Pacing Strategy for Swimming

Pacing patterns differ according to the distance of the event and the stroke.

a. Stroke

The stroke is important because each one has its own mechanical efficiency that influences how quickly the swimmer fatigues and determines how effective and feasible it is to change the stroke rate (or frequency) during a race.

The breaststroke is the least efficient of the strokes, whereas the freestyle is the most efficient4.

Swimming speed is equal to the stroke length multiplied by the stroke rate, and if stroke length can be maintained over a race, the stroke rate does not have to increase greatly to compensate.

In both the breaststroke and butterfly to increase the stroke rate, maintaining the stroke length is particularly important in these events.

The purpose of this strategy is to keep the power output of the arms from having to increase over the race to such an extent that excessive local muscle fatigue developed(6)

b. Distance

It has been postulated that sprint races are decided in the final 25 m of the 50 m event and the final 50 m of the 100 m event.

In the 200 m and 400 m events, the competitive advantage is gained in the second 50 m and 100 m laps, respectively,

and that gain is often largely maintained over the remainder of the race(5) (unpublished observations from the Australian Institute of Sport).

Arguably, coaches need to consider the subtlety of pacing strategies and the impact of them, because even a small change in racing speed will have a marked effect on the swimmer’s physiology.

c. Role of the Brain

Controlling emotion at the start of races is also important to avoid overriding the planned pacing strategy and internal pacing algorithm because of high motivation or arousal levels (e.g., deciding in the moment, ‘blow the strategy, I am just going to go for it!’).

The brain might not be receiving sufficient information or be able to process information rapidly enough, during the majority of a shorter event, to form a conscious or subconscious decision about the appropriateness of the pacing strategy. This makes it difficult to adjust a poor pacing strategy in time to affect the outcome of a short-distance race. Rather with no warning the muscles might demonstrate sudden fatigue, causing the stroke technique to begin to fail and in turn the swimming velocity to decrease.

Muscle fatigue (known as peripheral fatigue) would seem to set in before the brain is even aware that the pace is not appropriate. In contrast, during a longer race there is more time for feedback to reach the brain and be interpreted; the brain can initiate a response to a potential problem, such as fatigue developing too quickly, by slightly reducing the level of muscle activation to produce a slower but more sustainable pace.

d. Technology

Various systems have been tried over the years.

· Pacing lights

· Audible sound systems

· The Aquapacer system / Tempo Trainer Pro: Most Used by coaches and athletes to manipulate pace.

At the elite level of swimming, performance changes are small among competitors and competitions such that a 0.4 per cent change in performance either positively or negatively is a meaningful change. However, a controlled pre-race warm-up can negate some of the variation in performance by preparing the swimmer physiologically (Martin & Thompson 2000).

Coaches and swimmers must also pay attention to starts and turns because appreciable time gains can also be made here.

Coaches and sports scientists should consider greater individualisation when determining a swimmers’ optimal pacing strategy(7)


The key point here is that each aspect of performance needs to be evaluated and scrutinised, including the pacing strategy, because each aspect of the race is both marginally and critically important.


1. Thiel, C, Foster, C., Banzer, W. & de Koning, J.J. Pacing in Olympic track races: Competitive tactics versus best performance strategy. Journal of Sports Sciences. 2012;

2. Foster, C, Hendrickson, K.J., Peyer, K. et al. Pattern of developing the performance template. British Journal of Sports Medicine 2009;

3. Kevin, GT, PhD. Pacing : individual strategies for optimal performance. United States of America: Human Kinetics, Inc.

4. Holmer, I. Propulsive efficiency of breaststroke and freestyle swimming. European Journal of Applied Physiology. 1974;33(

5. Robertson, E, Pyne, D., Hopkins, W. & Anson,. Analysis of lap times in international swimming competitions. Journal of Sports Sciences,. 2009;1-9(

6. Chollet, D, Pelayo, P., Tourny, C., Sidney, M. Comparative analysis of 100 m and 200m events in the four strokes in top level swimmers. Journal of Human Movement Studies. 1996;31(

7. McGibbon, K, Pyne DB, Shephard ME, Thompson KG. Pacing in Swimming: A Systematic Review. . Sport. Med. Springer International Publishing;. 2018;


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