I don't know if it's obvious. For example, everyone always assumed ski jumpers should keep their skis together in the air, then someone realized the V technique with the skis spread wide actually allowed jumpers to travel farther.
How does this apply to swimming? I think conventional wisdom would suggest keeping the fingers together would be better because water wouldn't be able to slip through. However, spreading the fingers somewhat might actually increase the effective surface area--just like wearing paddles does.
I personally keep my fingers closed (as in I don't leave much of a gap between my fingers).....and the reasoning behind this is based on trying to catch as much water as possible during the first part of each stroke (i.e. just after the entry). If your fingers are spread apart too much it would seem (at least to me that is?) that you would end up slipping too much during the catch phase of the stroke....i.e. too much water would end up slipping through your fingers....and hence you wouldn't grab as much water as when your fingers are closed....(i.e. next to one another).
Hopefully that makes sense?
Newmastersswimmer
I tend to agree with Jim in theory but I have heard that it makes little to no difference in practice. I think there was some actual research done on this topic...perhaps a USMS'er will know about it and share.
I don't have any research to back this up, but I've been told to keep my fingers less than a finger-width apart. Whatever you do, don't tense up your hand too much - you don't want to waste energy trying to force your hands into the 'perfect' position.
Originally posted by LindsayNB
I can't cite a source but I have read that all that matters is the cross sectional area of the hand, the spread of the fingers does not affect the area so it does not effect the propulsion.
Do you mean the cross-sectional area of the hand as viewed from the side or as viewed looking at the palm? In the latter case I think it does change, at least effectively, when the fingers are spread. Sort of like a skydiver. To slow down they go into a spread eagle position. Their arms and legs are still exactly the same size as they were before, but by spreading them they are creating more air resistance.
Originally posted by geochuck
This subject is nothing new, have as little tension in the hands as possible, don't press the thumb against the index finger, don't cup the hand, don't hold the fingers tight against each other. The university of Wisconcin (I'm a Canadian the spelling may be wrong) ran tests in 1950 with a flat mechanical hand with the fingers in different positons the result it makes no difference,
I agree. In Swimming Fastest, I think he recommends entering your fingers slightly open. By nature my fingers are slightly spread. I'm finding as i get older, arthritis makes it really hard to hold my fingers together. I woudl think that the most ocmfortable or nature way would be the best.
This subject is nothing new, have as little tension in the hands as possible, don't press the thumb against the index finger, don't cup the hand, don't hold the fingers tight against each other. The university of Wisconcin (I'm a Canadian the spelling may be wrong) ran tests in 1950 with a flat mechanical hand with the fingers in different positons the result it makes no difference,
All I can say:
Do NOT cup the hand.
Do NOT squeeze and force your fingers together.
Do NOT swim with your fingers apart like a frog. You do not have webbed fingers. If you do...that's interesting.
DO keep your hands relaxed.
DO keep your fingers together and straight, but in a comfortable position. Your "paddle" goes from your fingertips to your elbow, so the straighter you an keep all of that, the better.
I can't cite a source but I have read that all that matters is the cross sectional area of the hand, the spread of the fingers does not affect the area so it does not effect the propulsion.
Along these lines it is interesting to consider the cross sectional area during sculling motions. If you rotate your wrist to 45 degrees you can see that spreading the fingers a bit does increase the cross sectional area as you can spread them a bit before beginning to see between them.
Originally posted by knelson
Do you mean the cross-sectional area of the hand as viewed from the side or as viewed looking at the palm? In the latter case I think it does change, at least effectively, when the fingers are spread. Sort of like a skydiver. To slow down they go into a spread eagle position. Their arms and legs are still exactly the same size as they were before, but by spreading them they are creating more air resistance.
I mean viewed looking at the palm. I know nothing about sky diving but my guess is that the spread eagle position has more to do with balance and control than how fast you fall, unless the sky diving suit acts as webbing. I would expect that a sky diver in a vertical position would fall faster due to the smaller profile but that your velocity would be the same if you were falling horizontally whether your limbs were out just enough to maximize your profile or spread eagled.
I think form drag is strictly a function of profile and that this was verified by the aforementioned study.
I suspect that the intuition that keeping your fingers together has the same basis as the intuition that cupping your hand will be effective and is based on the conception of the amount of water you are moving rather than the amount of drag is what is important. It might be instructive to think about holding your hand out, palm up, under a stream of falling sand. The sand will form a sort of cone/pyramid on your hand after which the following water will flow down the sides of the cone, water will do pretty much the same thing as you move your hand through it. Cupping your hand will result in a little more sand in your hand but that doesn't do you much good because you don't get your force by accelerating mass backward you get it from drag forces - which are reduced by the smaller profile of the cupped hand.
I think :)
