Using data to help you understand your swimming performance is one of the most efficient ways to help you improve in the water. With advances in wearable technology, the most important metrics can be tracked automatically and used to your advantage.
“If you can’t measure it, you can’t improve it.”
I completed the workout below wearing the Apple Watch Series 3 running the MySwimPro App’s Workout of the Day. The intervals on the workout were automatically personalized to my swimming level using the Dynamic Intervals module in Workout Settings.

Workout Statistics:

  • Distance: 3,000 Yards
  • Duration: 56 Minutes
  • Focus: Improving SWOLF

This workout is for our community members who swim with the Apple Watch. This week’s main set is a series of four rounds of 6 x 50s Freestyle where the goal is to decrease your SWOLF Score on each round of 50s. SWOLF is a measure of your swimming efficiency.
To calculate SWOLF, take the lap split and add it to the number of strokes for that length and normalize to 25 meters. For example if you swim 25 meters in 20 seconds in 15 strokes, your score is 35. For a more detailed explanation of how SWOLF works, checkout this Whiteboard Wednesday session.

Warmup Analysis

  • 1 x 400 Freestyle @ 5:30 (5:16)
  • 4 x 100 Kick @ 2:10 (1:35)
  • 4 x 100 IM @ 1:40 (1:16)
  • 4 x 50 Drill @ :50 (:39)
  • 1 x 200 Free @ 2:30 (2:20)

Below you can see the 200 freestyle broken up by 25 splits and the 4 x 100s IM. If you notice the changes in Stroke Count, Lap Split and SWOLF score for each of the 25s in the IM represent the different strokes being swum.

6 x 50s @ :50 (SWOLF)

On the first round 6 x 50s Freestyle, the goal is to maintain a baseline SWOLF Score. On this set, my baseline SWOLF was 30. I was averaging 34 seconds per 50 yards taking about 11 strokes per length.

  • Average 50 Split: :34
  • Average Stroke Count: 11/length
  • Average SWOLF: 30

6 x 50s @ :50 (SWOLF – 1)

  • Average 50 Split: :31
  • Average Stroke Count: 12/length
  • Average SWOLF: 29

6 x 50s @ :50 (SWOLF – 2)

  • Average 50 Split: :30
  • Average Stroke Count: 12/length
  • Average SWOLF: 29

6 x 50s @ :50 (SWOLF – 3)

  • Average 50 Split: :29
  • Average Stroke Count: 12/length
  • Average SWOLF: 28

Cool Down 200

On the cool down, you can see I swam the 200 in 2:23 with an average stroke count 13 holding about 35 seconds per 50 yards. My average SWOLF during warmup and cool down ranges from 33-35.

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  1. Pingback: How MySwimPro Helped Me Lose 75lbs – Reclaiming My Life

  2. Can I get advanced analytics using a Fitbit Versa? I’m looking for Stroke Count mostly. Do I need a different watch (Apple or Garmin)? Do I need the Elite Plan too?

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