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Comment by jerf | Hacker News Reader

I've been using a prompt that comes from the opposite direction for non-programming stuff: "Assume the user is an expert in all fields; while this is clearly logically untrue on a literal level, the user prefers to see a field's technical terminology and then ask the AI about terms the user does not understand rather than get an inaccurate statement about some issue."

Whether you have to reassure the LLM that this is obviously untrue, I don't know, but they do have a knowledge baseline to know it's not true and I have a sneaking suspicion it would be less effective without that.

This has ended up in some of the most interesting incidental knowledge exploration I've ever done. A recent example is that I was asking about some stretches and it started talking about how useful they are for the sarcomeres, which I had not heard of. Now I have.

I'm not saying this is better, just that it is different. I think there's a time and a place for both approaches.

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Off topic, but stretching is absolutely useless for ... stretching. And vital for retaining and enhancing usable range of motion (not static stretching, still, but dynamic stretching / mobility under tension).

The wildest thing is, there's no evidence that I can find that static stretching does... anything? It increases pain tolerance through the range of motion, but not any more than just asking people to try harder etc. And it doesn't build up, so after you stretch once for a given day, you're done.

Edit: after looking into it a bit further there's actually a cochrane review that stretching does bupkis, fascinating. It's also the first "Good" evidence graded cochrane review I've seen.

"And vital for retaining and enhancing usable range of motion (not static stretching, still, but dynamic stretching / mobility under tension)."

I'm doing it for knee pain. It's possible it's a placebo because there is a slight strength training component to the whole thing (it's several exercises), although the knee pain has persisted through a lot of strengthening of my leg in general. This falls under "don't care" as the program as a whole works and I'm not worried enough about the details to try to optimize it. All the stretches fall under "dynamic stretching under tension" so maybe it's not something covered by the study you reference last.

It’s not a placebo. I’m not sure exactly which Chocrane review the GP is talking about but if it’s the one I’m thinking of, the headline is that stretching doesn’t help muscle soreness [1] (delayed onset muscle soreness specifically).

You should absolutely keep stretching to help with your injury, and there is decades of “sport science” to back that up.

[1] https://www.cochrane.org/evidence/CD004577_stretching-preven... - there’s another one about joint deformities which is far more interesting, but less relevant to this discussion

I can tell you if I don't stretch, my muscles feel bad and stiff. No doubt this is partly because I did karate for a few years, where stretching to increase your range of motion is absolutely required. You're not going to "just try harder" into a high kick.

I think you probably just don't like to stretch.

Can you share the source? This seems dangerously wrong.

I see a specific review making the very narrow claim that it can have detrimental effects on power/strength activities immediately following static stretching.

But by and large I'm finding a great deal of evidence for a wide range of other benefits, particularly in range of motion and injury prevention. I can't find anything widely damning, and I certainly don't see any reviews contesting the validity of the very vast body of research supporting the many benefits of static stretching.

https://www.researchgate.net/publication/377653878_The_benef...

Most of this comment is not true. Static stretching does increase flexibility over time - it’s not the most efficient tool for it, but it’s certainly effective.

Presumably the Cochrane study you’re referring to is “Stretching to prevent or reduce muscle soreness after exercise”, which as it’s title suggests, investigates a narrow question and does not support you claim that “stretching does bupkis”.

Static stretching increases tendon length, among other things. The stretch MUST NOT cause pain, and MUST be steady for the duration of stretch. Some suitable duration increments are 10 sec. (absolute minimum), 30 sec., 60 sec. Multi-minute stretches are suitable if they can be held without discomfort.

Notably, longer tendons are counter-productive for energy return. The fastest runners tend to have increased tightness along the backs of their legs.

That's very interesting. It kind of mirrors the experience of having a very smart friend.

Edit: https://xkcd.com/2501/

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