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I have two related questions that deal with the same issue. My primary question is regarding swimming.

I've found that extending my stroke (pressing behind behind me to propel me further at the end of the stroke, I'm not referring to reaching far in front of me at the beginning of the stroke) seems to require more energy than what it requires at the beginning portion. At what point during the stroke does your arm lose its efficiency and it becomes worthwhile to begin your next stroke? The question would seem to need a comparison of the additional energy required for a lengthy stroke vs a series of smaller ones that provide the same propulsion. How much energy is wasted performing the preparatory movements for each new stroke? Assume I'm referring to a standard front crawl.

Related to this question is a similar one for walking, hiking, or climbing stairs. How much energy does each stride (or step up on stairs) require versus taking a more lengthy stride? Does this change when loaded with a hiking pack? Does bounding up stairs use more energy than walking them? What if I only used enough energy to allow my foot to clear the upper step and not more?

Thank you.

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In terms of your swimming question: If you take longer strokes your body is naturally in a more streamline position for a strong glide which in turn uses less energy. It is also the most efficient way to swim quicker, fast longer strokes. The more you train the less tired you will get.

Again, naturally it depends on your body composition, and structure. some people find it easier for short steps/strokes some vice versa.

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  • Mmm...not really. Swimming strokes for speed (50m, 100m) are much different in length and turnover than swimming for distance (1500m, 500m). The basic motion is the same, but the strokes are shorter and faster the shorter the race. – JohnP♦ Oct 17 '18 at 13:56
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    youtube.com/watch?v=9eAiTyJhpl0 - Here is a decent comparison. Note the 1500m swimmers have a much more "front quadrant" stroke, where the lead arm is still ahead of the body at the same time the recovery arm is being extended. In the 50m swimmers, it is much more of a "windmill" pattern, as the lead arm is under the body and pushing back as the recovery arm is coming forward. Swimming has more pronounced differences in speed strokes than distance strokes than you will find in running. – JohnP♦ Oct 17 '18 at 14:03
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    These comments are essentially the answer I was looking for. Based on what you're saying, sprint-swimmers have longer strokes which likely makes them faster but also likely burns more energy, however, since they are only swimming for a short distance long term energy savings is not that important to them. This is in contrast to distance swimmers who need to ensure efficiency of energy spent and thus use a shorter stroke. Did I summarize that correctly? – MBak Oct 17 '18 at 15:06
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    I think that is an okay summary, but really only within the context of racing. And from the phrasing in your original question, I'm going to guess that racing is not exactly what you were interested in. Stroke length is just one component of stroke efficiency, which also includes body position, head position, arm position, hand position, body rotation, kick sequence, breathing patterns, etc. – zigzag Oct 17 '18 at 16:02
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I'm going to attack this from a more general point of view. Your broad question is "should I use a longer stride with less frequency, or a shorter one with more frequency?"

Roughly speaking, as speed goes up -think slow walk to faster and faster- we go from relying on frequency, then we quickly transition to longer strides, then we go back to using more frequency and more more length.

Another way to view it:

  • Slow walk => short strides
  • Faster walk => strides get longer
  • Jog => frequency picks up / strides get even longer

That's a rough idea of what the average human does. When I was in college, it was then presumed humans had it optimized. That is, so many fall into that pattern, and humans are so good at minimizing metabolic cost, that's probably the best way to approach it.

For instance, if you want to go from slow walk to fast walk, you should probably rely on stride length, not frequency. In other words, do what's natural, opposed to trying to outthink nature.

I realize this may not be as precise as you want, but the moment you try to get more precise than this you will run into trouble.

Reason being you are going to be extremely hard pressed to find any hard rules about what's optimal for you, and you will easily find exceptions to any "rule."

We don't even have hard rules for elite performance.

For a long time it was assumed 100 meter sprinters could not be too tall. The thinking was their height made it take them too long to get going in the early stages of the race. Their stride frequency just couldn't be high enough to compete with shorter sprinters. The average 100 meter world record holder was remarkably steadily around 6 foot, give or take an inch or two.

Then came Asafa Powell at 6'3".

And then came Usain Bolt at 6'5".

Bolt, a guy whose stride looks like this. (He has a big shoulder lean to the right, because he has scoliosis!)

Michael Johnson long held the world record in the 400 meters. He had a bizarre looking stride. He was huge on stride frequency.

Michael Johnson stride

Two of the fastest people ever; two very different gaits.

Whether you're tall or short, have long legs relative to your torso, have achilles tendons which have a better stretch reflex or not, whether you're in-shape enough to go two steps at a time or whether it will quickly burn you out, these are all going to factor in to what works best for you when e.g. climbing stairs.

No way to find out except experiment.

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  • Good answer, especially the notation about what is right for you. Research has shown that runners tend to self select the stride length that is best for them, and speed gains (in endurance running at least) are mainly due to increased turnover as speed increases. – JohnP♦ Oct 17 '18 at 13:55
  • Interesting response, although not particularly useful (not a fault of yours, but rather of the fact of the matter). But my essential question is still unanswered. Which provides more motive energy (measured by moving from point A to point B) while burning and equal or lesser amount of my energy, assuming that the only difference between the two movements is the frequency/stride length? – MBak Oct 17 '18 at 15:12
  • @MBaka - As far as burning energy, your energy cost to move from point A to point B remains pretty much unchanged with speed. If point A is 5 miles from point B, and your physiology is such that you burn 500 calories to cover that distance, it will burn 500 calories if you do it in an hour or in 30 minutes. – JohnP♦ Oct 17 '18 at 20:29
  • @JohnP What I was saying was not that efficiency goes up or down due to speed alone, but rather the manner in which the speed is achieved. I'm assuming that swimmer or sprinters use more energy due to decreased efficiency which allows the, additional speed, versus a long distance swimmer or runner who plays close attention to performing his actions in the most efficient manner possible. – MBak Oct 19 '18 at 16:00
  • @MBaka - Mmm, to some extent yes, part of the energy cost is increased resistance (to air or water) as you increase speed. But part of metabolic adaptation is increased energy efficiency the more you do a thing. Yes, better form = better results, but even with poor form, your body adapts to use less energy to produce the same results. Am I understanding what you are getting at? – JohnP♦ Oct 19 '18 at 16:03

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