SWOLF on Garmin: what it measures, how to read it and how to lower it

What is SWOLF?

SWOLF (a blend of swim and golf) is an efficiency score: for one length, you add the time in seconds and the number of arm strokes. A 25 m length swum in 22 seconds with 18 strokes gives a SWOLF of 40. As in golf, lower is better: either you go faster with the same number of strokes, or you take fewer strokes for the same time.

Your Garmin watch computes it on every pool length using the accelerometer, which counts strokes and detects turns. Garmin Connect then shows the average SWOLF of the session and, in the detail, that of each length and each interval. Running Workout reuses it in the analysis of your swim sessions.

What is a good SWOLF?

SWOLF depends on the pool length, the stroke and your height: it only compares to yourself, in the same pool and the same stroke. In freestyle, in a 25 m pool, these orders of magnitude are observed:

In a 50 m pool, the score roughly doubles, and a breaststroke length naturally has a higher SWOLF than freestyle, with longer cycles. What matters is how your score evolves over several weeks, at a comparable pace.

Reading pitfalls

• — A low SWOLF obtained by gliding a long time after each stroke isn't progress: you're swimming slower. Always read SWOLF together with the length time.
• — The watch sometimes counts one extra stroke at the turn or misses one on a short length: judge on an interval's average, not on one length.
• — Garmin counts one stroke per arm in freestyle and backstroke, one full cycle in breaststroke and butterfly: scores across strokes don't compare.
• — A wrong pool length setting on the watch skews everything: check "25 m" or "50 m" before each session.
• — SWOLF doesn't exist in open water: no wall, no length.

Three sessions to bring SWOLF down

1. Counting your strokes

8 × 50 m freestyle, 20 seconds rest, counting your strokes on every length and trying to remove one every 50 m without slowing down. It's the basic drill: it teaches a longer stroke and a better glide after the push.

2. Glide drills

4 × (50 m catch-up + 50 m full stroke), with a pull buoy if needed. Catch-up, where one hand waits for the other in front, forces the reach. Then 4 × 25 m with closed fists, which forces you to feel the forearm catch.

3. Constant SWOLF at rising pace

6 × 100 m, each 100 m slightly faster than the previous one, keeping the same stroke count per length. If the count rises, the pace is too fast for your current technique: that's exactly the limit you're trying to push back.

These sessions are created in one sentence with Running Workout: "Create a 1,500 m session in a 25 m pool with 8 × 50 m freestyle and 20 s rest, for Wednesday". Your assistant sends the session to the watch with distances, rests and stroke type, and you find each interval's SWOLF in the analysis.

Frequently asked questions