SWOLF, derived from swimming & golf, measures your performance in swimming. You'll get your SWOLF score by swimming one length of a pool and counting the number of strokes you take. You count the strokes from each hand. Use a timer to get your swim time in seconds. Then add your strokes to your time, for example 45 strokes + 55 seconds. The result is 100 and that is your SWOLF score. SWOLF scores from different pool sizes are not comparable: if your SWOLF score is 100 in a long course pool, it's about 50 in a short course pool.