His experience is perfectly in line with the results of the study:

> weekend recovery sleep had some benefits after a single week of insufficient sleep

Just like 'ferros' described, if you have a single occasional week of limited sleep, making it up on the weekends DOES have benefits. The problem starts when you repeatedly sleep an inadequate number of hours during the week.

I think that description is upside down: being sleep deprived during the week causes a large number of problems and sleeping extra on weekends doesn't have benefits, rather it mitigates some of the problems caused by the sleep deprivation. You don't get any benefits over someone who sleeps all they need during the week.

The "science" in the linked WaPo article, and the science from the journal, weakly indicate that if you get 5 hours of sleep each night for an entire work week you will get fat, and sleeping in for an extra hour on the weekend won't stop you getting even more fat when you do the same thing on Monday and Tuesday.

This has almost nothing to do with what ferros said. No, resting on the weekend won't uneat or burn the extra calories, in the same way that it won't rewrite all your bad code or help your fuzzy memory, but it could very well help you perform at a more normal level the next week.

How does sleeping less make you fat? Eating more will make you fat, eating less will make you less fat. If you sleep less you have more time to eat more, but that still requires the eating to happen.

Sleep deprivation causes overeating.

Towards the end of the book The Hungry Brain, by Guyenet, there's a reference to research where both the sleep deprived group and the control group are let loose in the city and allowed to eat whatever they wanted, conditioned on letting the researchers weight and classify it first.

On average, the sleep deprived group ate around 300 calories more.

(sorry I can't produce the original reference, I don't have the book with me)

From my understanding on this topic, the problem has more to do with insulin sensitivity. It has been measured that insulin sensitivity is worse the day after a poor night's sleep and insulin resistance can help drive fat accumulation, all other things being equal.

Sleep deprivation makes you hungrier, increases your appetite and cravings, gives you headaches and makes you feel miserable if you don't eat more.

The mechanism that drives this are the hormones ghrelin and leptin. Look up their action if you're interested.

"Calories in" is only part of the equation. Sleep metabolism is different from waking metabolism.

Also, to your point, very few people spend their sleeping hours eating. You could eat 1500 calories for every meal and be very lithe - if you slept 23 hours a day. By contrast, it seems anecdotally that people who get less sleep tend to eat more food and more of it is unhealthy: late night Taco Bell, delivery when you're pulling an all-nighter, etc.

Best diet pill on the market? Unisom.

> You could eat 1500 calories for every meal and be very lithe - if you slept 23 hours a day.

Not sure if this statement is sound, for the average person.

If you ate 4500 per day, spread across 3, 20 minute meals, and spent the remaining 23 hours sleeping... your energy expenditure would be minimal, whilst your energy intake large. The average person would gain weight rapidly. (300lb athletes perhaps not, but these are outliers).

But if it "feels that way", doesnt that have something to say as well?

In the absence of any actual evidence? Generally we take self-reported feelings as not especially strong evidence.

Maybe all it says is they grew up thinking that "weekend sleeping helped catch-up" and now they only remember the confirming evidence and discard the disconfirming evidence to support their confirmation bias?

I think the actual evidence, for the OP, is that he/she feels better. I don't think it matters if no one else feels better. OP isn't making a scientific claim other than they feel better after a weekend of sleep.

I have a friend who deeply believes that he can drink unlimited amounts of beer and not get drunk. He will drive his car home after drinking 10 beers.

Should his feelings count as evidence in any meaningful sense?

Or do we generally assume that his feelings -- especially since they are contrary to science -- are not a good guide to what really happens?

Self-reported statements (about how someone feels) are good evidence for how they feel. In your example, if the claim is that your friend believes he is not drunk, then his experience still carries more weight (is a more reliable indicator of his beliefs) than most studies.

This is different from the question of whether he is actually sober, of course. But the post you're replying to is specifically about the claim that X person feels better, not about any physical effects on their body. I'd rather trust a person about how they say they feel (especially at a given moment), than studies trying to determine how most people probably feel or ought to feel in a similar situation.

And remember that spinach has a lot of iron, butter is good for you in 1940, bad for you in 1970, good for you in 2010.

Margarine is good for you in 1970, bad for you in 2010.

Good luck.

Wait, what? Why would self-reported feelings not be taken as strong evidence? It seems to me like self-reported feelings are great evidence, and need particularly strong evidence (e.g. evidence of long-term damage that isn’t felt in the short term, like for smoking cigarettes) to contradict.

> Wait, what? Why would self-reported feelings not be taken as strong evidence?

Because you might be stuck in a local maxima that's close to your global minima. I've been reading "Why We Sleep", and while I don't have the citations here at the moment he mentions that one of the tricky things with sleep deprivation is that people are often not very aware of it themselves. Your body gets used to the new, lower, level and thinks that it's normal.

It should also be mentioned that most people don't try to distinguish between correlation and causation, and as such it can be hard to draw any conclusions. Imagine a person who reports that "I'm so happy when I drink alcohol", but it turns out that he has no social contact (e.g. working at night, sleeping through the day; no friends) outside of the bar setting, and it's actually the social element that he most desires.

I guess it depends on what you mean by the word "evidence", but I wouldn't really say that his self-reported feelings show any strong evidence that alcohol makes him happy.

[0] https://www.goodreads.com/book/show/34466963-why-we-sleep

Because we're really good at fooling ourselves, and we lie to present an idealised version of ourselves.

Example: [Apparently] having coffee in the morning doesn't wake you up, it's that caffeine dependency (and maybe a little dehydration) makes you feel terrible. Coffee temporarily reverse this negative [local maxima].

Coffee appears to wake you up, but it's doing the opposite.

There are many common examples - 'drinking doesn't affect my driving', 'I don't drink heavily', 'advertising doesn't affect me', 'I get enough exercise', 'my diet is healthy', 'I go to church regularly'.

Reports here https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5639921/#!po=7...., for example, have measured overreporting of exercise/church attendance at double.

Except a lot of studies and protocols do rely on self-assessment of conditions.

Pain scores, Depression scores are the ones I remember right now

So yes, it is something that's used because you don't have a way of directly measuring all things

In the ends its about how you feel, your well being. Right?

The important thing to keep in mind there is that it doesn't much matter what the science tells you: It makes you feel better and it costs you almost nothing. That makes it a valuable pursuit even if we couldn't find evidence for it working (though another post in this chain mentions some evidence that it does work for a single week).

When sleeping more shortens my waking life, I really want to know how important it is.

If your waking life feels like shit when you don't sleep an hour more, I don't know what more incentive you need to sleep an hour more (given that you are free to do so).

That's a very important question that should be answered, but your implicit assumption that sleeping shortens waking life should at least be verified. It looks like chronic lack of sleep shortens life expectancy.

No, because it's not predictive. Thousands of things could cause that feeling, there's no telling it's the catch up sleep.

The point is you can't do anything with his anecdote. It gives you no more information about what you should do, and is therefore technically useless.

It feels that way but only temporarily. When I keep repeating it not sleeping, my weekend is spent only sleeping and my weekday performance begins to drop, eventually I need to sleep in even on week days.

Only way I've managed to recover is to take an entire month off, sleep as much as I want for the first week (or two) and slowly try to shift back into an 8 hour cycle.

Sure, if there are some long-term negative effects, then I’d like to see them. But this article doesn’t claim or show that. So if that commenter feels like the weekend catchup works, then I would say that it does in fact work, by definition.