“When bottlenose dolphins swim — at a cruising speed around six miles an hour or a sprinting speed about twice that fast — they are constantly fighting against the water’s drag, which only gets worse as they swim harder.
Shawn R. Noren, a marine biologist at the University of California, Santa Cruz, set out to find how much extra drag would be experienced by a specific, aerodynamically disadvantaged subset of the dolphin population: adult females nearing the end of pregnancy.
…Pregnant dolphins also swim differently, making shorter but more frequent strokes. And the growing fetus stretches out the mother’s muscles, probably making it more difficult for her to thrust her tail up and down.”
www.nytimes.com/.../different-strokes-for-pregnant-dolphins.html
What can we swimmers learn from this? How does it relate to stroke rate and distance per stroke?
Through no fault of my own, I find that I have a less than optimal hydrodynamic profile. I wouldn't say I look like a pregnant dolphin, but opinions may vary. Should I shorten my stroke and increase my stroke rate to compensate for this unfortunate circumstance?
Discuss...
Former Member
Through no fault of my own, I find that I have a less than optimal hydrodynamic profile. I wouldn't say I look like a pregnant dolphin, but opinions may vary...
:lmao:
I doubt that what works for a dolphin would work for me. Actually, when I weighed more I found the added buoyancy annoying, my balance was off. I much prefer being thinner. At my current weight, I have close to neutral buoyancy.
But dolphins are built differently. I have long arms and legs. They have flippers. My body length is about 1/3 of my total length, dolphins are almost all body length.
And that doesn't explain why my Siberian Husky can outswim me with her head and tail way out of the water. Maybe I should dog paddle.
Umm... dolphins don't take strokes... they use their tail and "kick".
Perhaps you need to focus on reducing the amplitude of your kick and increasing it's frequency. I think this is a more relevant comparison.
I think it makes some sense intuitively. The pregnant dolphins are less streamlined, so they can't glide as effectively. They make up for this by gliding less, i.e., kicking more frequently. Obviously there are lots of differences between the way dolphins and humans swim, but maybe the most obvious is dolphins swim primarily underwater. Would the technique adjustments pregnant dolphins make also apply to swimming in the surface? Hard to say for sure.
I think this research is pretty relevant to aging Masters swimmers who are experiencing reductions in strength, range of motion, and maybe a larger hydrodynamic profile. It sure seems that nature is telling us to take smaller and faster strokes when facing these constraints.
I don't agree with older swimmers taking smaller faster arm strokes.
they should move through their full range of motion.
It might be more beneficial for swimmers to do smaller faster SDKs
smaller amplitude, less knee bend
higher frequency
Former Member
I think it makes some sense intuitively. The pregnant dolphins are less streamlined, so they can't glide as effectively. They make up for this by gliding less, i.e., kicking more frequently. Obviously there are lots of differences between the way dolphins and humans swim, but maybe the most obvious is dolphins swim primarily underwater. Would the technique adjustments pregnant dolphins make also apply to swimming in the surface? Hard to say for sure.
Nicely stated. I think the adaptive changes do cross over from dolphins to human swimming.
the author & proof readers should have caught this error
"aerodynamically disadvantaged subset of the dolphin population"
they should have written "hydrodynamicly"
Wonder how much slower pregnant dolphins are versus ones that aren't?
Former Member
the author & proof readers should have caught this error
"aerodynamically disadvantaged subset of the dolphin population"
they should have written "hydrodynamicly"
Wonder how much slower pregnant dolphins are versus ones that aren't?
From the research paper summary...
"Pregnancy also induced a gait change as stroke amplitude and distance per stroke were reduced by 13 and 14%, respectively, compared with non-pregnant periods. This was concomitant with a 62 and 44% reduction in mean and maximum swim speeds..."
"Their top speed was restricted to 3.54 m s–1"
In all seriousness, I think this research is pretty relevant to aging Masters swimmers who are experiencing reductions in strength, range of motion, and maybe a larger hydrodynamic profile. It sure seems that nature is telling us to take smaller and faster strokes when facing these constraints.
Former Member
Be wary of doing something just because a dolphin does it. Came across this wonderful piece about why elephants are more useful for learning about swimming than fish/dolphins.
coachsci.sdsu.edu/.../ofmen30.htm
