Thứ Hai, 15 tháng 8, 2016

rhythm, timing and stroke rate in swimming

what are rhythm and timing?
When a great swimmer is moving quickly through the water they seem smooth and powerful. But look carefully, there are no lurches, pauses, hitches or dead spots in their stroke technique - they have excellent rhythm and timing, moving seamlessly from one phase of the stroke to the other.
There was a trend at the end of the 20th century amongst age group triathletes and swimmers towards developing really long strokes - to try and go as far as possible on one stroke because it was seen to be more efficient. (aside: the elite triathlon and swimming world didn't subscribe to this theory).
Swimmers are now realising that there's more to fast efficient freestyle than the length of your stroke and thatan overly-long stroke can be less efficient because of the introduction of dead spots and pauses.
Swim Smooth are at the forefront of the movement away from overly long strokes. We suggest you need to find the right balance between stroke length and stroke rate. Read on to find out more.
too much of a good thing?
A long stroke is a good thing up to a point. Think about where a long stroke comes from:
Good propulsion comes from a good catch, pull and push. It means you go further on each stroke as you are propelling yourself forward better. This is a good factor in a long stroke.
Low drag comes from a good body position, a straight body and an effective kick. Low drag means you go further on each stroke because you slip through the water more easily. This is a good factor in a long stroke.
'Glide' is a Dirty Word!
Swim Smooth believe that the word 'glide' has a lot to answer for! When you add an element of glide into your stroke you introduce a pause. That hurts your rhythm. Imagine riding a bike and pausing on every pedal stroke!
When you glide you also slow down. On your next stroke you have to re-accelerate yourself, which feels hard.
Have you experienced this? Do you have a long stroke but on each stroke it feels hard, like a lot of force is required to maintain the long stroke? That's because you're having to re-accelerate all your body mass on every stroke!
Remove the glide, don't decelerate between strokes and it'll feel easier and be faster.
A 'glide' in the stroke means you pause and wait a while before performing the next stroke, gliding a bit further off the last stroke. This is a bad factor in a long stroke because you lose touch with your rhythm and timing. You also slow down in the glide phase and then have to re-accelerate yourself with the next stroke - that's hard work!
So,having a long stroke is a good thing up to a point but it shouldn't be achieved by sacrificing your rhythm and timing or by introducing pauses into your stroke technique.
short strokes
Of course you can also have too short a stroke! If your stroke is short and scrappy with a very fast turn over then you need to sacrifice some of that stroke rate at this stage, slow things down a little and work on your propulsion and lowering your drag. This will give you a longer stroke technique, which in the long run you can look to speed up again.
Whether you are looking to improve your rhythm and timing or looking to slow things down, it's good to have a handle on your stroke rate.
stroke rate
Your stroke rate is how many strokes you take per minute (counting both arms). This is useful to know because it tells you about your rhythm and timing. Too low a stroke rate and your arms are moving over too slowly and you almost certainly have some big deadspots in your timing. Too high a stroke rate shows your stroke technique is too short and needs lengthening.
Stroke rate is a powerful thing to know because these days you can precisely control it with a tool called the Wetronome. This allows you to make changes to your stroke rate and develop your stroke for the better. We'll explain how from the links below.
75 strokes per minute - Ian Thorpe's racing stroke rate.
where do you fit in?
First you need to know your stroke rate. If you've been using a Wetronome it's easy, you'll know what stroke rate you swim at. If not, ask a friend or coach to time you for 10 strokes with a stopwatch (don't include any push-offs, just normal swimming). Put this time in this box and press calculate:
Time for 10 strokes:
(seconds)
Stroke rate:
Now, look up where you are on this chart using your stroke rate and the pace you are swimming. The chart works for any effort level e.g. easy, steady or sprinting:
Find yourself on the chart by entering your stroke rate and swimming pace:
Stroke Rate (strokes/minute):  Swimming Pace (secs/100m): 
We have nick-named this the "BMI Chart" because it reminds us of the Body Mass Index charts you find in a doctors surgery.
One word of caution - this chart is nearly always right but is not complete gospel. For instance, if you're exceptionally tall you might want to be on the blue borderline. If you are very short with short arms for your height then you may be best bordering on the red region with a high stroke rate. But for 99% of adult swimmers, aim for the white region.
For further technique advice follow these links:
swim smooth's simple stroke calculator
If you like numbers you may like to experiment with our stroke rate calculator below. Enter your stroke length and stroke rate and see how it effects your swim times:
Pool Length:
Your Strokes Per Length:
Your Stroke Rate Per Minute
(counting both arms) :
Your Length of Push Off in meters
(if you're not sure, use 3) :
100m time:
400m time:
1500m time:
3800m time:
See how trade offs between stroke length and stroke rate work for you.
Dive
Everyone has a sweet spot in their stroke.
the stroke rate ramp test
Swim Smooth have designed a special test to help you understand your individual stroke efficiency and find the optimal stroke rate for you. Find this stroke rate 'sweet spot' in your technique and you will swim faster for the same effort.

Everyone should run their stroke through the Stroke Rate Ramp Test. Full details here.
Resource: swimsmooth.com

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