Coaching, Training, Camps.

How to Improve Swimming Efficiency
by Sarah Wright

Here you are in August as your latest triathlon season is winding down. You have improved drastically since you first started racing but you still find yourself at the back of the pack on the swim. For this reason, you have decided to dedicate this off-season to focusing on your swimming performance.  Even with high intensity and high frequency training, only marginal improvements will be made if poor technique is maintained. Spending this off season working on rectifying asymmetries and increasing resistance training will lead to a more powerful and efficient stroke that translates well to open water.

According to the Journal of Swimming Research, asymmetries in a swimming stroke can lead to a multitude of muscular imbalances and inefficiencies that ultimately can result in injury (Sanders et. al 2011). For example, it is commonly seen that the catch phase of the freestyle stroke is longer for the dominant arm than the non-dominant arm, causing the body to adjust for a shorter stroke length on the non-dominant side. This side preference can place more stress on the non-dominant shoulder and result in less power being produced when rotating to the non-dominant side. Additionally, asymmetries in pedal strokes or running strides can cause muscular imbalances and side preference that translates to the swimming stroke. The body is more efficient at using the dominant arm muscles as they resist fatigue better than the non-dominant arm.

How do you know if you have these asymmetries and how can you fix them? The most beneficial tool would be to have a BEST coach videotape your stroke underwater from the side and swimming directly towards the camera. Being able to see your stroke and visualize the asymmetries is incredibly valuable. Another powerful tool is drills to help you feel the imbalances of the stroke. The following progression is useful in determining asymmetries but also can be used as drill progression to improve the stroke as a whole.

  • With fins on, kick on side with bottom arm straight in front squeezing ear, top arm resting on side. Focus on keeping a strong core and your arms, head, hips, and feet in alignment. Switch sides after 25 yards. Be aware of hips sinking and one side being more difficult than the other
  • Do the above drill but switch every 20, 10, or 6 kicks focusing on rotating from the hips
  • 1 arm freestyle with fins. Rotate fully to both sides. Leave one arm by side the whole time while swimming normally with other arm. Breathe every stroke to opposite side of arm that is swimming. If you have asymmetries, you will feel them with this drill. After a 25, switch to using the other arm.
  • Further progression would be completing the above drills without fins

To address these asymmetries and improve swimming efficiency, resistance training should also be incorporated into your swimming routine in addition to the above drills. Crowley et al. determined that low repetitions and high force will improve distance traveled per stroke and stroke length (2017). Resistance training also helps maintain good technique and minimize asymmetries while fatigued (Sanders et. Al 2011). Target areas should include arms, shoulders, back, core, and hips. There are an endless number of exercises to do to strengthen these areas so here are my favorites with links to how to do them. Remember to maintain low repetitions and high force (2-3 sets of 8-12 reps, nearly reaching fatigue by the end of the last set):

Good luck and happy training!


Works Cited:
Crowley, Emmet, et al. “The Impact of Resistance Training on Swimming Performance: A Systematic Review.” Sports Medicine, 12 May 2017, pp. 1–23.,

Sanders, Ross H, et al. “Asymmetries in Swimming: Where Do They Come from?” Journal of Swimming Research, vol. 18, 2011.

Wells, Randy. “Functional Dryland for Swimming.” American Swimming Coaches Association.