Smart Speed Part 2 – Effective Stroke Rate
We looking at the next part of our Speed Equation in this essay:
Speed = Stroke Length (SL) x Stroke Rate (SR)
In the previous essay I introduced Stroke Length and discussed how we can each find our own optimal SL for various conditions and events. Now we are going to examine how to develop Stroke Rate in a way that it makes you speed up rather than just get tired out.
Stroke Rate is how many strokes are taken in a set amount of time. SR is often measured in units of strokes per minute. Among TI swimmers we most often refer to Tempo, which is seconds per stroke, the inverse of Stroke Rate (after converting all units to either seconds or minutes).
SR = 1/Tempo
Tempo = 1/SR
(when comparing make sure the time units are the same for each)
- 50 strokes per minute is 1.20 seconds per stroke;
- 60 strokes per minute is 1.00 seconds per stroke;
- 70 strokes per minute is 0.85 seconds per stroke; and
- 80 strokes per minute is 0.75 seconds per stroke.
I will use the terms SR and Tempo interchangeably while talking about the concepts, but when doing the math it is important to note which one we are working with.
Here is one thing to keep in mind: Stroke Rate means nothing without Stroke Length. We develop SL first, then build SR on top of it.
You can observe someone in the water spinning their arms as fast as they can, making as much a splash as they can, but it doesn’t mean they are going anywhere fast. Stroke Rate is deceptively easy to improve unless it is done in strict combination with Stroke Length.
Side tip: Noise, bubbles, waves and splash equal wasted energy. Simple hydrodynamics. Don’t let those swimmers who make a lot of these intimidate you- the proof of their waste is obvious. You’ll be able to go fast with a fraction of the effort if you aim for precision instead of power. Quiet swimming leads to fast swimming.
Increasing Stroke Rate alone is easy to do. Just spin those arms! Increasing Stroke Length is much more difficult. Increasing Stroke Rate while preserving Stroke Length is a whole step more difficult than that, and the key to improving your speed capacity.
Once we develop the ability to hold a certain Stroke Length over the distance we are aiming for, our next step is to increase our SR while holding that same SL.
This is a basic pathway I prescribe for training:
- Develop SL
- Develop SR while protecting SL
- Develop more ease (less effort) while holding SL x SR combinations
- Increase distance and/or intensity while holding SL x SR combinations
I introduced #1 to you in the previous essay. I will discuss #3 and #4 and introduce you to more complex training concepts in later essays. Let’s look at #2 for now.
For instance, I may be able to hold 16 SPL (a SL of 1.25 meters using the chart from the previous essay) for 1500 in open-water. But that does not tell me how fast I covered that distance, or more specifically how quickly I was able to cover 1.25 meters in each stroke. For this I need to know Stroke Rate.
If I held 1.25 meters per stroke for 1500 meters, with a Tempo of 1.20 seconds per stroke (which equals a SR of 50 strokes per minute) I would finish with a time of 24 minutes exactly.
If I want to improve my time to 22 minutes while holding the same SL I have to increase to a Tempo of 1.10 seconds per stroke.
Here is where your get to engage your brain, and do a little math to design your own tasks for improving your speed.
There are 3 objective ways you can improve your speed:
- Hold SL and increase SR
- Hold SR and increase SL
- Increase both SL and SR
I have listed these generally in order of difficulty. You may be inclined to work on either SL or SR- perhaps some people are better at long strokes while others have a naturally faster SR. But once you near your kinesthetic limits in one variable, you’ll be compelled to work on the other. There is no escape from this speed puzzle, and ignoring the facts does not help- why not master it instead!
Let’s examine a few charts ** to demonstrate this puzzle and how we can solve it. In each chart we’ll be able to see the benefit or cost of adjusting one of the variables.
HOLD Pace, CHANGE Stroke Length and Stroke Rate
The first chart is going to show us how we can use different SL and SR combinations (SPL x Tempo) to achieve an 80 second 100 meter distance (4 laps in the pool).
(Note: the equation I used to make this chart factors some time and distance for the push-off or turn.)
For this example I have shown the SPL that fits within the range of someone with my wingspan of 1.79 meters and tempos that are also within my range.
Starting at 15 SPL, you can see that if I add one stroke per 25 meters then I have to increase Tempo by 0.07 seconds to hold the same pace. Give up another stroke and I have to increase Tempo another 0.06 seconds. Give up another stroke and I have to increase Tempo 0.05 seconds more. If you’ve ever used a Tempo Trainer at higher tempos, you’ll realize that 0.05 seconds is a big jump up in Tempo in the middle of a hard effort. You’ll be pushing into anaerobic zone quickly without giving your neuro-muscular system more time to adapt with more gradual increases in Tempo.
This may help you understand why even the world’s fastest swimmers in the Olympics, near the end of their 100 or 200 meter sprint, while appearing to swim faster (we see their SR increasing dramatically), are actually slowing down. Their SL is deteriating faster than their increasing SR can compensate for it. In essence, even while SR increases, the one who holds the longest stroke wins.
If you are new to SL x SR variables, you can use this example set of SL x SR combinations in my chart to test yourself, or calculate your own set using a more suitable pace. Using a Tempo Trainer, try each combination out to discover which one allows you to swim this pace with the least amount of effort. Then you can start working on improving your variables from this starting point.
HOLD Stroke Length, INCREASE Stroke Rate
This will take great concentration and an understanding of how to shave time off each stroke without interrupting the Stroke Length, AND keeping your Effort level the same. It can be done. This is one of the secrets of Total Immersion’s approach to advanced training. It requires understanding of each element of the stroke and body position, and absolute mental focus to maintain stroke quality. But the wonderful things is that by just beginning to practice this way we develop the sensitivity to detail and focus that we need to achieve it.
Tempo Threshold is what we call that point at which you can’t hold SL if you increase Tempo any more. You may find you have different thresholds at different Stroke Lengths or distances. When you discoverone spend more time right near that threshold, right before it and right up to it. When you are ready to push over it, take much smaller incremental increases in Tempo- 0.01 or 0.02 second increases and stay there for 200 or 300 meters to give your brain time to adapt and build neurological control over stroke quality while making faster movements. Give yourself plenty of rest in between repeats too so that you are able to keep pushing your neural threshold rather than your anaerobic threshold. Always keep in focus what you are working on and don’t confuse the two.
When you do this correctly you’ll notice that it is becoming increasingly more difficult to focus on holding stroke quality before you are actually too physically tired to continue. This is what I call neurological exhaustion in contrast to muscular exhaustion. When you learn to recognize the difference between the two and intentionally design your practices to push your neurological limits (think “FOCUS”) you will gain a major training advantage.
HOLD Stroke Rate, INCREASE Stroke Length
Now let’s look at what happens when we hold SR and increase SL. This is the more difficult of the two skills to develop when we get near our personal Tempo Threshold.
You can see how reclaiming 1 stroke per length while holding Tempo can improve my pace by 4 seconds.
Again, the real challenge is to increase SL without increasing Effort level. This will be the subject of the next essay.
In Total Immersion’s approach to training, counting strokes will become a habit, then eventually it will become intuitive- so that we know at what SL we are swimming even without counting, or more importantly, when there are no walls. It is an indespensible skill for those who compete in the pool and for open-water swimmers who intend to keep pace without someone else to watch it for you.
In addition, tempo training will become a standard piece of your TI practice. After enough time is spent working on specific tempo ranges, and improving them while protecting SL, tempo will also become something we are able to sense accurately without having a Tempo Trainer or timing device to check it.
Anyone competing in pool or open-water will have a serious advantage when they can set, hold and adjust their SL x SR combinations at will. without the aid of walls and beeping devices. Advanced TI training will show you how to train your body to feel both SL and SR intuitively and achieve this.
** ** **
** I have programmed a handy (but complex) little calculator to crunch these numbers for me. The parameters I’ve set to get the data I put on these charts is assuming a 25 meter pool, a 5 meter glide, taking 2 beeps (2x the tempo) to cover that 5 meter glide. Stroke Count #0 starts at the second beep (where the first underwater propulsive stroke likely starts), and Last Stroke Count at the wall. Conveniently, you can simply use these same figures in units of yards without changing a number.