It’s common knowledge that a semi-truck at 60mph takes longer to stop than a car at 60mph because the greater mass/weight wants to keep on going even without further propulsion.
The same is true for ships. It takes a massive freighter filled with products much longer to stop than a small speed boat when they are both traveling at X knots per hour and they cut propulsion at the same time.
Therefore I think a swimmer’s mass/weight plays a significant roll in their speed and stroke. Swimming favors a heavier swimmer and a 6’ swimmer at 220 lbs.will out perform a 6’ swimmer at 140 lbs. We see it all the time at championship meets. Swimming is a self-selecting sport that favors mass and a greater mass creates a longer stroke because the mass wants to keep on moving even when propulsion is not occurring.
There are exceptions and those exceptions involve people with a high SPM and/or kick to overcome lack of mass.
It seems like mass/weight could be more significant than height in stroke length. Yet, big swimmers might not really want to credit their mass/weight to their success because that might take away from the talk about what a great stroke they have in comparison to runners and other lightweights. Just like a heavyweight might want to fight a lightweight and then claim it was skill and talent.
No extremes of 400 pound people who can’t swim well nor 80 pound people who can’t run well either. Or eating a big meal and it not helping your swim. Nor adding weights to your body, etc. and all kinds of things one can make up. Let’s deal with what we see and not hypotheticals. Let’s stay within gender and compare guys to guys and gals to gals.
How much does mass/weight effect swim speed and stroke length? My take is that it makes a big difference.
Not much. Not much at all. Fat floats and muscle sinks, but weight is almost completely negated in water. Mass is constant, but mass effects acceleration more than velocity.
Mass is pretty much irrelevant, except if you throw in how well that mass floats. A long time ago I had a very smart coach do a test with a lot of us big mass male swimmers against some 14 year old small mass girls. We all ran about 15 yards and jumped as hard as you could into the pool and then coasted until we all stopped. Of course all us big strong guys jumped much higher and further than the little girls, but funny thing happened on the coast to the other side of the pool. Those girls just kept gliding until they hit the other side, while we all stopped somewhere before. Our mass without propulsion was useless and even a big negative.
It is all about the float when it comes to mass, taking propulsion out of the equation of course… And your inherant hydrodynamics would also be a big factor, Sun Yang is tall but anything but massive. Probably cannot do 20 pushups either, but he floats and pokes a super tiny hole in the water with a super long hull. He is the surfski of swimmers.
Mass is pretty much irrelevant, except if you throw in how well that mass floats. A long time ago I had a very smart coach do a test with a lot of us big mass male swimmers against some 14 year old small mass girls. We all ran about 15 yards and jumped as hard as you could into the pool and then coasted until we all stopped. Of course all us big strong guys jumped much higher and further than the little girls, but funny thing happened on the coast to the other side of the pool. Those girls just kept gliding until they hit the other side, while we all stopped somewhere before. Our mass without propulsion was useless and even a big negative.
It is all about the float when it comes to mass, taking propulsion out of the equation of course… And your inherant hydrodynamics would also be a big factor, Sun Yang is tall but anything but massive. Probably cannot do 20 pushups either, but he floats and pokes a super tiny hole in the water with a super long hull. He is the surfski of swimmers.
Again a guy to girl comparison rather than a guy to guy comparison. With fat/buoyancy, smoother skin, different body shape, etc. it’s an apples to oranges comparison.
How did you do guy to guy as a large group and not a n=1?
Sun Yang is massive to me at 196 lbs. What throws most people off is there often is a correlation of height to weight and we attribute some gains made by weight to height. However, one could have a relatively tall swimmer who has a tendency to snake through the water because they have a longer “chain” to control than a smaller swimmer of the same weight which would be a hindrance.
Not much. Not much at all. Fat floats and muscle sinks, but weight is almost completely negated in water. Mass is constant, but mass effects acceleration more than velocity.
Why then do massive boats travel farther than smaller boats both traveling at X when propulsion is stopped?
Only if the mass is dedicated to making the swimmer swim faster – swim specific muscle to be exact*. Otherwise, attaching weights to yourself would help you swim faster according to your logic – and that’s not good logic.
*Even swim specific muscle has its limits here. The world’s fastest man is 6’3" and weighs 190 lbs. That’s not exactly massive for a 6’3" person.
Not much. Not much at all. Fat floats and muscle sinks, but weight is almost completely negated in water. Mass is constant, but mass effects acceleration more than velocity.
Why then do massive boats travel farther than smaller boats both traveling at X when propiulsion is stopped?
Because boats slowing down is acceleration, and that is effected by mass. Like i said previously.
All depends on how that mass is distributed. There are always outliers, but for the most part it is better to be longer and lighter in freestyle. Length of waterline is important. For “long axis” strokes it seems it is better to have a longer torso and shorter legs, proportionally.
Here’s a good example with data:
A front pack swimmer pro triathlete who I have worked with can swim at 1.8m a second and produces a little over 100 watts to swim at that speed. He is about 6’2’’ and weighs about 170-175 pounds.
I am 6 feet tall, I weigh about 205-210 pounds. I was also able to swim at about 1.8m a second, but I needed to produce about 140 watts to go that speed.
Largely most of the answers in this thread have been a bit wrong totally dismissing weight. It matters, but I don’t think to the degree you are proposing. To get the correct answer you take two vessels with the same hydrodynamics in terms of shape and then launch them from a torpedo bay, and make sure one weighs much than the other, but launch both at the exact same velocity and see which one goes further. Both will have the same displacement in the water (taking float out of the equation since they are submerged) and then you should see that the heavier one goes further. The problem with this discussion is the the hydrodynamic drag is not only affected by the weight, but by float (fatty vs non fatty as Monty pointed out). The more floaty vessel will displace less water and have less drag. This is why in my torpedo example above, I did not say “take two boats and fill one with more weight”. The moment you do that, the heavy boat will have more drag since it will displace more water. Since swimming happens at the surface, it’s really complex. A lighter swimmer may suffer more momentum issues, but may also float higher so it could be a net gain over a heavier larger swimmer who may sink more and displace more. Overall height and wingspan and size of hands and feet should have the biggest impact.
I think an example of lighter versus heavier swimmer is young Janet Evans vs older Janet Evans. Pretty well same technique, but the heavier version of her was slower if I recall correctly.
Remember David Berkoff? He weighed in at 154 when he competed and is 5’9 or so.
Another great example is Mike O’Brien, who won the 1500 m at the’84 Oly; he was 6’6.6" and only 151 lbs at age 18 in '84. Four yrs later he had “filled out” to 160.
Regarding the OP’s original question, I do think there is some correlation between swim speed and swim-specific strength, and I think that strength is generally correlated with bigger muscles. For instance, while as SH pointed the fastest man in the world is 6’3’ and 190; while certainly 190 is not “massive” for 6’3", it is much bigger than a pure elite runner, who even if he were 6’3", would not prob weigh much more that 140-ish. Pure runners with lightly muscled upper bodies will generally swim slower than more muscular guys. Often here on ST the non-swimmers will point out that the young swimmers are often very skinny but, if they were to look closely, they would see that even very wiry little kids have some muscle to pull with, i.e. they have enough for their lower weights of 90-100 lbs or so.
She was slower, but then she was also 40 compared to being a teenager. But then, Dara Torres was faster (but a sprinter, sprinters seem to have more longevity). Lots of confounding factors.
Weight increases momentum, but also frontal area.
When I look at the worlds best middle distance and up swimmers, they tend to be tall and lean, or average height and really lean. some sprint specialists pack a lot of muscle, but that’s the demands of the event. The weight that is carried is there for propulsion.
All depends on how that mass is distributed. There are always outliers, but for the most part it is better to be longer and lighter in freestyle. Length of waterline is important. For “long axis” strokes it seems it is better to have a longer torso and shorter legs, proportionally.
Here’s a good example with data:
A front pack swimmer pro triathlete who I have worked with can swim at 1.8m a second and produces a little over 100 watts to swim at that speed. He is about 6’2’’ and weighs about 170-175 pounds.
I am 6 feet tall, I weigh about 205-210 pounds. I was also able to swim at about 1.8m a second, but I needed to produce about 140 watts to go that speed.
Hope this helps.
Tim
Just out of curiosity, how did you come up with those 140W vs 100W measurement. Is this just power applied by arms on a Vasa Erg…it would be hard to measure mechanical power generated by core and legs. My gut feeling is people under estimate the amount of mechanical power applied to the water from all parts of the body. At a 4:1 ratio, between heat and mechanical power, I find it hard to be believe for example that someone like Patrick Lange is only delivering say 120W of mechanical total power to the water from all parts of the body. If he was only putting out 120W of work and generating 480W of heat, he could probably keep swimming for forever at that intensity. 600W of total mechanical + heat work is pretty low. An average human sitting around is generating 200W of heat (that’s what we used as a rule of thumb for aircraft avionics/cooling systems design)…that’s just sitting around, no exercise. I’d bet that someone like Lange is working as hard overall (mechanical work + heat) in the water as he is on the bike.
It’s a “power meter†for the water. You have a belt on and swim out against it. It has some issues, but it’s fairly accurate and the velocity measurements are very accurate.
It’s a “power meter†for the water. You have a belt on and swim out against it. It has some issues, but it’s fairly accurate and the velocity measurements are very accurate.
Tim
So basically something that measures how many molecules/mass of water is going through a finite cross section and then inferring a projected power number for the human towing it based on some assumption of the human’s own water displacement?
Let’s do the math though. for a swimmer going at 100W, that is 500W total heat + mechanical. This equates to 500W x 3600 seconds = 1800 kilojoules per hour. If you divide that by 4 you get how many calories the swimmer is consuming per hour of 450 cals.
If the swimmer is going 1.8 meters per second, an IM swim in 3800m/1.8 ~ 35 min IM swim split. There is no way under the sun that anyone is doing an IM swim split doing only 100W mechanical or 500W of total work. To swim that fast, you have to roll through a boatload of higher calories not 450 cals per hour rate which is our 100W number in terms of calories per hour burned.
So whatever device is doing the measuring it is way underestimating. If you just look at it from heat+work done in an hour, it seems way off.
Only if the mass is dedicated to making the swimmer swim faster – swim specific muscle to be exact*. Otherwise, attaching weights to yourself would help you swim faster according to your logic – and that’s not good logic.
*Even swim specific muscle has its limits here. The world’s fastest man is 6’3" and weighs 190 lbs. That’s not exactly massive for a 6’3" person.
Agreed and that’s why I wrote don’t include such nonsense like adding a weight to you while you swim.
And to your/our point sport specific mass that is moving is an advantage.
Not much. Not much at all. Fat floats and muscle sinks, but weight is almost completely negated in water. Mass is constant, but mass effects acceleration more than velocity.
Why then do massive boats travel farther than smaller boats both traveling at X when propiulsion is stopped?
Because boats slowing down is acceleration, and that is effected by mass. Like i said previously.
Look, your hypothesis is wrong. Move on.
Findin, respectfully, isn’t the mass of the boats important in fighting de-acceleration. And isn’t that an advantage that larger swimmers and larger boats have?
