why does it hurt to swim too fast at low SPL?

[Danny]

Wow, Charles, that is very enlightening (if I understand it) so I will paraphrase a bit, just to reduce this to the stuff I can get my head around.

First, when your DPS is too large for your stroke rate, the variation in your speed over one cycle will be larger than optimal. When you sacrifice DPS for stroke rate, you swim at a more uniform speed over the course of a cycle. This is a very helpful insight for me.

So, how to choose what is optimal for you? Well, obviously, by what feels most comfortable, but the rest of what you said seems to be a discussion of the pros and cons of swimming at non-optimal DPS as a training method. When your speed variation is too large, the emphasis shifts more to minimizing water resistance, but also to training the muscles and nervous system to get a good grip on the water. This is what is needed to maximize glide but also to generate the propulsion needed for the large oscillations in speed. All of this can be beneficial as long as it doesn't become a habit. In the end, we need to be able to tune these trade-offs to find the optimal balance for us.

I might add that this answers a question I have had for a long time, which is why we can't hold a DPS that is too large for us over distance. It is because we are working our muscles too hard to generate all of this acceleration and glide. Sounds obvious when put this way.

I hope I've gotten this right. Thanks for your help!

[CoachSuzanne]

Originally Posted by CharlesCouturier

Therefore my original statement in this discussion is a bit fallascious. Swimming can't directly be compared to running and cycling, none of which being a sport of glide. The similarity is strong enough to make the analogy legitimate though, I didn't cheat.

What some claim is that there should not be any dead spot in the way you pull. But that's fine. We're saying the same thing. While you set up for catch, you're not being "propulsive" with this phase. It's a setup phase. For TI, it's the skate phase. What triggers the war, is that in spite of clearly seeing no dead spot in Terry's stroke for instance, he still uses the word "glide" during the skate phase, which he sees as a phase during which you glide. Anyway... Let's not divert.

While you set up for catch, or stated otherwise, as long as you haven't taken a catch, you're not propulsive. Normally, the effective pulling range in freestyle can not be 180deg. During the non propulsive phase, what are you doing after all... You're gliding. Hopefully not wasting that time and rather setting up to be ready to pull when... when what?

When your body forward velocity drops below the target pace you wanna hold. In other words, gliding, i.e. not having taken a catch yet becomes a bad thing when you let your forward body velocity dropping too much. This is all obvious. I just want to make sure we move in our explanation one step at the time.

Well explained, Charles!

[Talvi]

In this imo you can compare swimming with XC-skiing.

I have flat spots, probably more flat spots than a Golf after a Saturday night of doughnutting. These are clearly a sign that my stroke is poor BUT ... what I find is that focusing on eliminating them is counterproductive. Maybe this is merely another proof of Appreciative Inquiry but ....

It's the same with my XC-skiing (when there used to be winters in Finland that is). My real problem is patience not laziness. As soon as a technique improvement gets me moving the buzz makes me try and push. That then destroys the small improvement in technique. It results only in a lot more energy being expended, with a faster stride/stroke rate and little or even nothing to show for it (except, maybe, less noticeable flat spots).

For me the challenge is to feel the glide, not to feel the push, in XC-skiing anyway, and it seems to be identical thing in swimming.

[haschu33]

I understand that this is about swimming too fast at a low SPL (or long DPS), both of it, at the same time.

Can someone help me with what is meant by 'too fast' and what is meant by 'low SPL' in this context here? Is it independent of the absolute speed (i.e. that what you can measure from the deck) about that very combination of 'too fast' and 'low SPL'? Or is there a context of a given speed, particularly a fast speed?

Thanks in advance...

[CoachSuzanne]

Originally Posted by haschu33

I understand that this is about swimming too fast at a low SPL (or long DPS), both of it, at the same time.

Can someone help me with what is meant by 'too fast' and what is meant by 'low SPL' in this context here? Is it independent of the absolute speed (i.e. that what you can measure from the deck) about that very combination of 'too fast' and 'low SPL'? Or is there a context of a given speed, particularly a fast speed?

Thanks in advance...

Let's say you have an SPL range to start with. Said range is 3 or more strokes. ie 14,15,16. Or if skilled it maybe 6 strokes (14,15,16,17,18,19).

Let's say at 15 strokes (near the low end) you can swim 100m/yd in 2:00 flat with ease and you could do this all day.

2 ways at which the conditions in the subject of this thread could come true
a) Swimming same pace at fewer strokes (100 in 2:00 @14SPL)
b) Swimming same SPL at a faster pace (100 in 1:55 @ 15SPL)

It's impossible to say what SPL, what rate of increase and what change in SPL would be parameters to avoid, so lots of practice & trial & error is needed.

At some point in the above example, swimming further @ the same SPL & pace combo will be come taxing and maintaining the low SPL becomes a force or strength based exercise.

If that force creates lingering pain, discomfort or uncertainty (apprehension) about the shoulders, then it's too low and/or too fast.

[WFEGb]

Hello haschu33,

Mat just wrote a great blog about:

http://mediterraswim.com/2014/11/29/...sier-swimming/

Best regards,
Werner

[Zenturtle]

Hnmmm, couldnt agree more, but not exactly a new discovery.

Its not about the rate or the lenght of the stroke, but about the quality of the stroke.

Hard to define quality in a few numbers.

[Talvi]

In "general terms": Pace = SPL x Stroke rate. This means that if the values of any two of these numbers are known then the other one is then fixed. Or in other words any discussion only needs to refer to two of the three. If three are referred to circular reasonings and thinking can easily result.

My lay answer to the OP is that if pace is increased by means of lowering spl rather than increasing stroke rate then the amount of energy required for each stroke increases. In other words each cycle of a muscle used in the stroke will be more demanding even though applied over a longer period.

In "general" mechanical terms, this is the principle that makes pulleys and gears effective. It's easier to do the work required by adding together lots of little bits of work rather than in big bits. Cycling up a hill you change down gears so that your legs move around faster. The amount of effort required to get you and the bike up the hill is precisely the same, but it's easier for your muscles/skeleton to work within the range it's comfortable.

[Danny]

Talvi, the important part of the process with swimming is the role that glide plays in all of this, so I think there is more involved than just gears. At the same pace but a lower SPL your speed will vary more over the course of a cycle. This acceleration/deceleration has a price. How much you pay depends on (a) how good a grip you have on the water, which makes acceleration easier and (b) how little water resistance you have, which hinders deceleration. These factors don't come into the gear analogy, but I think they are critical in swimming. This is the point that I understood Charles to be making.

[Talvi]

Hi Danny

Interesting point but I don't see it affects the gear analogy. If anything it seems to strengthen it. The "llower gear" i.e the more rapid stroke rate or higher spl (the same thing if pace is constant) also has a a more continuous speed/power delivery.

Good technique is another thing. We must always compare apples with apples.