How much does body weight effect swimming speed?

I don't think this is rocket science. Lightest boat with the most powerful engine goes the fastest or at least comes the closest to its potential...(assuming the strokes are good). There is a balance out there. I little extra body fat probably isn't going to hurt you. May even help with buoyancy. But I mean a "little extra". Look at the swimmers in their prime, competing at their best....olympics and nationals, etc. None are overweight. There are a couple of exceptions who are a bit doughy--certainly not overweight. They are exceptions to the general rule, though, which is to be as light and powerful as possible.

Solar Energy, I think what you said has some merit, but there is an underlying assumption you are making that is, in my opinion, suspect. If a person said, "I have advanced metastatic cancer for which no viable treatment exists," I do not think you would have said, "Hey, buddy. Get that fixed or you are going to die!" There is a widespread assumption in our "Can Do" culture, no doubt based in part on a mix of Calvinism and individuality, that weight is something people can "fix" with the right mix of self-denial, internal fortitude, and character. More and more, however, I think the evidence shows that overcoming ones genetic set-point is infinitely harder than the normal-weighted community imagines. True, some people do manage to lose a lot of weight, and keep this off long term. But the overwhelming majority don't. In the next decades, I think that significant alteration of body weight is going to be viewed as only slightly more subject to will-power and sustained change as sexual orientation.

Maybe it's an immeasurable, but I thought I'd ask for opinion anyway. I'm hoping it doesn't turn into a "to diet or not to diet" discussion though. I am really sorry, and I am sure it's been mentioned already, but at 6'2 270 with a beer gut, swim performances are going to become the least of your concerns passed a certain age. A bit like someone driving a car about too loose a wheel asking if the car could be faster by dropping little of weight. I expect no "thanks for the feed back solar" here, and you can even be harsh on me if you want, since I went against what you were expecting as a feed back. Sorry.

According to the lightweight boat, powerful engine (overly simplistic, in my opinion) model, the answer would be a clear yes. That's right, keep everything simple and then make it more simple. However, this implies that the only considerations are strength and mass (with, perhaps, a bit of hull shape thrown in there as well.) Not true. Don't forget about the powerful engine which includes all the physiological processes. Remember we are talking about the "optimal" body weight. Which I believe is the lightest frame that still allows for a very powerful engine. My further hypothesis: world record masters holders do not allow themselves to go to fat. But neither do they consider body weight and fat percentage the most critical element of their training. Agreed, weight is not the most critical factor. It is just one of many limiting factors. Could I be wrong about this? Possibly, but I think we are all saying the same thing. If you are 6'2" 270, then your boat is almost surely too heavy to swim up to your potential. Body weight and shape matter. Let's neither delude nor outsmart ourselves here.

Look at the swimmers in their prime, competing at their best....olympics and nationals, etc. None are overweight. . True, but whats the cause vs effect here? To be a world class swimmer it takes a huge amount of training. Doing 10-15k meters a day is not conducive to weight gain.

Alternately you could try one of the USMS smiley workouts, take your pick: :bliss: :bliss: Bliss, of course, is my favorite! I wonder how many calories he burns off with all that running back and forth? Surely, he burns off the chocolate I've been consuming, lately, after my super-healthy dinners... :D

I think all those Olympic level swimmers could support themselves and a small family offering a new a sure fire diet: "If you swim my workouts, I guarantee you'll get super lean and fit!" Alternately you could try one of the USMS smiley workouts, take your pick: :bliss: :bouncing: :bow: :bolt:

A further wrinkle to consider here. We are talking about masters swimmers. A wealth of studies seem to suggest that slow, steady accrual of body weight over the lifespan, even in those who train fiendishly, is not only inevitable but healthy. I am not talking about obesity here, just some weight gain from, say, your 20s to your 60s. If, for the sake of argument, we stipulate that human beings are designed to gain some weight with the passing years, the question becomes would a 55 year old swimmer, who maybe outweighs his college morph by 20 lb., swim faster if he could somehow shed those 20 lb. and return to his collegiate fighting weight? According to the lightweight boat, powerful engine (overly simplistic, in my opinion) model, the answer would be a clear yes. However, this implies that the only considerations are strength and mass (with, perhaps, a bit of hull shape thrown in there as well.) I would argue that there are many physiological processes going on inside of us, things that are not easily visible, from insulin and other hormonal changes with age, to sarcopenia of aging, that may, in fact, overwhelm the obvious external, easy-to-see items like body weight and stomach protrusion. Losing this 20 lb. is not without consequences. You may well gain something vis a vis the lighter boat you will sport once the metamorphosis is complete. However, I would argue that you may lose even more in terms of these internal processes. The caloric deficit necessary to fight Mother Nature, for instance, may make it impossible for you to train as hard as you would if you were consuming the calories your body is telling you it needs. Your testosterone levels might be altered by the food deprivation, too, in such a way as to impact muscle mass. I am not saying this definitely takes place, just that there are a host of variables that might be negatively impacted and overwhelm the advantages of the lighter weight. Swimming, because of water's buoyancy, is much more forgiving of body weight than land sports. I think it would be interesting to look at the World Record holders in masters age groups. My hypothesis: there are probably few highly overweight people who hold these. However, I would not be surprised that many, if not most, weigh more than they once did, and that this increase in BMI post college and high school probably creeps up steadily at least through the 60s. My further hypothesis: world record masters holders do not allow themselves to go to fat. But neither do they consider body weight and fat percentage the most critical element of their training. They do not, in other words, squander too much effort, physical or emotional, obsessing about weight and trying to be much leaner than their bodies' set points have apparently established. Could I be wrong about this? I would like to say perhaps. But in good conscience I can't. I am not wrong!

True, but whats the cause vs effect here? To be a world class swimmer it takes a huge amount of training. Doing 10-15k meters a day is not conducive to weight gain. I think we are talking about two different things. I'm talking about a light frame and powerful engine being the best for the fastest possible swimming. Perhaps you are talking about swimming being conducive to weight loss?? Forgive me if I'm misunderstanding you. The cause of the best performances isn't based solely on body type. It is just one necessary factor to arrive at your potential. Furthermore, looking at masters and seeing some overweight gals and guys is really not a fair look at the real question. Because some "chunky" stud of a masters swimmer is real fast doesn't mean that being heavy doesn't slow them down. Just means they are not as fast as they could be. Be as light and as powerful as possible, which requires finding your "optimal" body weight, and your body will aid your performances and not hinder your speed.

True, but whats the cause vs effect here? To be a world class swimmer it takes a huge amount of training. Doing 10-15k meters a day is not conducive to weight gain. Ahh, after another moment of thought, I understand what you're saying. Correct me if I'm wrong, but you're asking whether the body weight/type of the best swimmers is an effect of the training that they do and not a cause of the performance. It's an interesting question and an interesting conversation but I believe ultimately going to prove wrong. Some genetic freak would have arrived by now that is heavy regardless of training and shown the world that fatter swimmers are faster. That's about the best I can do.