There seems to be a general lack of misunderstanding regarding the Distance Per Stroke (DPS) swim drill that we see so often written into training plans and referenced in swim and triathlete magazines. Most of the time I see swimmers understanding that the sole purpose of this drill is see how few strokes they take during each length of the pool. And in taking less strokes, it’s believed that one will become faster because they’re streamline longer and use less energy because of the fewer strokes. All these potential results sound really great right? The problem is that the typical age grouper takes this drill to the extreme and it becomes a competition with themselves or their swim friends to see if they can get fewer strokes this week than they did last week. In doing so the swimmer loses focus on the ultimate goal which is to get from point A to point B as efficiently as possible and ready to get on the bike.
I can’t blame a swimmers for thinking this as “the lowest stroke rate, the better” tends to be the way that the drill is delivered. Just by doing a quick Google search I found these explanations that help explain the confusion.
- “The higher your DPS (or lower stroke count) for every 25-metres in the pool the better.” (Source)
- “When you slow down your stroke, but increase the distance and the power of each stroke then you speed up.” (Source)
- “Efficient technique maximize the distance you swim per stroke. Several drills focus on maximizing distance per stroke. The simplest focuses on counting the number of strokes in one lap and then working to minimize it by one for each lap you swim.” (Source)
These are all reputable sources so I’m not going to say that they’re wrong, because they aren’t. It’s just that there’s more explanation needed in order for us to completely understand the purpose of this drill.
When a swimmer takes this drill to the extreme they start to take so few strokes and glide for such a long time that there are large dead spots in their stroke that have to be filled with either kicking, which will hurt the your bike and run, or there’s just a complete pause in forward momentum where the swimmer slows down or possibly even stops. Then what? Now that the swimmer has started to slow down they must regain their forward momentum with the next stroke. So they stroke hard and glide again, doing this over and over again for up to 2.4 miles. Think of it this way, get in your car and go for a drive but instead of keep your foot steadily on the gas pedal you pump the pedal causing the car to surge every second. How good of gas mileage do you think you’re getting? Not very good right. The same thing translates to you swim efficiency.
So what is the purpose of the DPS drill? The way that one gets faster in the pool (and in the run for that matter) is to increase stroke rate (SR) or stroke length (SL) (SR x SL= Speed). There is a delicate balancing act in play here as over emphasis on one side of the equation will effect the other side to its detriment. For example, we have all probably done the GOLF drill in the poll as prescribed by our coach, training plan or we just heard that it was an important drill so we started doing it. Say you go through a set of 4×50 GOLF drills and these are the results that you get (first number is Time in sec., second is SR and last is your GOLF score):
- 50 + 35 = 85
- 52 + 38 = 90
- 42 + 44 = 86
- 45 + 40 = 85
If we just look at these results what do we learn about the swimmer? Not a whole heck of a lot other than that the GOLF score is the same for number’s 1 & 4 with a pretty significant difference in stroke rate. There’s are a number of problem here’s though. One key factor that’s missing is being able to know how each 50 felt. After all, isn’t the point to find your most efficient stroke rate, and isn’t efficiency based on finding out how fast you can go for the entire duration of your race? Intervals 1 & 4 have the same (and lowest) golf score but there’s quite a big difference in 35 or 40 strokes per 50. Without knowing how each of these 50’s felt we can’t suggest a stroke rate that is possibly the best for this swimmer. If 40 strokes per 50 was a 5 on a 10 scale and 35 was a 6.5 then the swimmer would be doing themselves a disservice by trying to sustain 35 simply because they’re told that the lower stroke rate is “better”.
Also, notice that the swimmer is jumping all around with stroke rates. One thing that’s impossible to do is to keep a consistent stroke rate while in the pool without the aid of something like a Finis Tempo Trainer but how many of us have one of these? Say that the swimmer is most efficient at 40 strokes-per-minute. Now what? As the swimmer goes through their workouts it isn’t until the end of the 50 that the swimmer knows if they swam at the correct stroke rate or not. If they were low then more than likely they’ll over correct and end up too high on the next 50, followed by being too low on the following. The whole thing ends up being a big up and down of stroke rates where the swimmer never really settles into that ideal stroke rate.
Trying to train yourself down to the least number of strokes humanly possible might sound like a good idea but the fatigue gained by either powering through each subsequent stroke or having to kick harder to fill the gap just aren’t worth it.
Next week the topic will be stroke rate and why it’s not like the run or the bike.