Stroke Counting is the first objective metric we teach swimmers in TI and one of the most important. It is the first indicator of how efficient the stroke is (but not the only one, and it is not a complete indicator by itself).
We use the term Strokes Per Length (SPL) which is the number of strokes taken across the pool. This assumes a push-off and glide distance from the wall. And the count depends on the length of the pool. So be aware, if you want to compare your SPL to another swimmer’s SPL you need to know if your push-off and method of counting are the same or not.
The standard way of counting among TI swimmers is this:
Push-off from the wall in streamline body position. When the first hand begins to catch the water this is Stroke moment #0. When that hand comes around and touches the water to begin the extension forward, that is Stroke #1. Count each hand as it touches the water after the recovery.
Getting a consistent reading on your SPL depends on having a consistent push-off from the wall, and finishing at the far wall in the same way. You may notice if you would finish the last stroke right at the wall or if you would need to glide a bit farther to reach it- you may note this in your stroke counting. I tend to count in 1/2 stroke increments, aware that I used another extra 1/2 stroke or glide to get to the wall.