Hacker News Reader

Comment by viraptor | Hacker News Reader

> Most of us have forgotten what it really feels like to be awake.”

This may be one part of it. Some time ago, I'd definitely tell you I'm fine with little sleep. You can do it if you sleep very little every night. It's quite easy to adapt to, for example during university exam times

But then after some years you realise you're not actually fine. You just don't remember how different is it to sleep longer. I'm still fighting with myself now to sleep for a reasonable time to reverse the old habit. I did tell people I'm fine with little sleep before. I will happily tell them now that I was lying - just didn't know it at the time.

View on HN

In grad school, I made it a point to cut-off my studying to get a consistent 7-9 hours of sleep in the days leading up to each exam. It worked enormously better for me than my sleep-deprived cram sessions in undergrad, and I think some of my classmates suffered for prioritizing taking another pass over the material instead of being well-rested.

Considering the brain needs to sleep to fixate memories, your approach is better. Of course, assuming you can fall asleep - if you can't because you feel you haven't studied enough...

"Considering the brain needs to sleep to fixate memories, your approach is better."

There are two other components to this that you're glossing over. Sleep helps with long-term memory. So if your plan is to study-ahead and be prepared for the exam, fine. But then the second component comes in to play. People that are cramming for the exam are doing so because they didn't study ahead. For that second group of people, sleep is actually the last thing they need. What good is remembering something long-term, if you never actually "learned" it in the first place. And let's be honest, people that are cramming for exams, are not the type to have learned the content before, either. (Though I generalize a bit there)

I know sleep is crucial for long term memories, but I also thought a lack of sleep affects all forms of recollection?

I had a period of a few years where I slept very poorly due to allergies. During that time, I was practicing guitar intensively. Despite lots of practice, my playing ability barely improved the whole time; I was not retaining the muscle memory necessary to continue to improve.

Now I practice much less and focus on my health. My abilities seem to increase on their own on a slow-but-noticeable basis.

After doing cram sessions for my exams, I've started to fall asleep during the reading of the materials I was supposed to memorize without even noticing it. The interesting part is that I would reiterate over everything I read so far in my dreams after which I would wake up and figure out that I actually fell asleep. Everytime after such short power naps, I had much better recall of information I've retained and I felt refreshed and relaxed.

>' You just don't remember how different is it to sleep longer.'

Exactly.

Not too long ago the combination of child, work and school forced me to completely re-evaluate how I was spending my time and what is actually important to me.

One big change I ended up making was getting to bed at the same time every night and clocking a consistent 8 hours.

Within a week or so the difference was remarkable in both my mood and acuity through the mid-afternoon - ideally I'd take a 45 minute nap around 13:30, but that's not an option with my current job.

In order of effect, the best things I've ever done for day to day clarity:

1.) Going to bed and rising at consistent times with 8 hours inbetween.

2.) Drinking plenty of water. At least 8 ounces per waking hour for me.

3.) Regular exercise. I feel best lifting weights 3 or 4 days a week, but I expect the specifics are less important than simple movement and exertion.

That was my experience too, though I think my enthusiasm for #3 was the main driver of the others. I found I really enjoyed lifting, and was much more successful when I was sleeping and eating well, so it became a virtuous cycle. With all of that, the depression and migraine issues that had plagued me through high school, university, and the following years became pretty scarce. If I change any of those things though, problems quickly become apparent.

> At least 8 ounces per waking hour for me.

That's 3.8L per day [(24 hours - 8 hours sleeping) * 8 fl oz = 3.8L]. Recommended intake is 2-3L[1]. Just be careful of water poisoning...

[1] http://www.mayoclinic.org/healthy-living/nutrition-and-healt...

This is all dependent on your level of exercise and rate of perspiration. A 72kg person would have to drink around 6.5L of water for it to become dangerous[1].

[1] http://www.sciencelab.com/msds.php?msdsId=9927321

Sure.

My case is a bit unusual as I'm far above average in height and weight. On average, the recommendation for my size is around 5.0L/day. In relation to that, the top of my head figure of 3.8L seems like a good lower bound.

It's always interesting trying to do conversions in a world made for folks are 5'8" and <200lbs. I'd be shredded to the bone if had a 'healthy' BMI and I'd be dropping pounds a week on a 2000 calorie diet.

Interesting fact - a healthy person's kidneys can excrete 25 litres of water a day. Drink more than this, and you expand your total body water volume to dangerous levels, which can lead to swelling in soft tissues and lungs (which can be life threatening). This happens in patients with psychogenic polydipsia.

Of course, drinking anywhere near 25L is not 'safe' either, and can still cause electrolyte abnormalities, neurocognitive dysfunction, seizures... Stick to the recommended intake, adjusted for water losses during significant exertion or high temperatures.

Unless I'm mistaken, water poisoning is only a credible threat when you consume exclusively those high volumes of water and nothing else to raise the salinity of the water in and around your cells. Over the course of a day, most of us get (much) more than enough sodium from other sources to eliminate any risk of water poisoning from 3.8L of water per day.

Yeah -- similarly to you, I'm pretty convinced that water poisoning is only a worry if you're unwell (mentally and/or otherwise) or do unusual things like water-drinking competitions.

Ecstasy and water poisoning are related. Ecstasy makes users extremely thirsty. Water poisoning related deaths at raves have been reported. About 6 L is enough to put a lot of people in a very dangerous place.

You just don't remember how different is it to sleep longer.

Exercise is like that, too. If you stay relatively stationary for a few weeks, then get out and do some serious exercise, you are more awake than you remember possible.

Similarly, smoking (especially green) and drinking are like that, too. When you stop, it takes awhile to get over, then it's amazing.

Probably being outside in nature in general has additional benefits, re: general sensory stimulation, removal of droning mechanical/electric noise, variety of light conditions, rhythmic subtleties of tone in the shadow of a moving tree, etc.

You notice northern hemisphere people that come to the tropics revert near-instantly to depression when boarding flights back home in their winter. I saw it in a set of Russians in Vietnam earlier this year... it was incredibly well choreographed!

PS. I went on a brief hunt via thesaurus.com and Wikipedia for an effect along the lines of 'acclimatisation' but failed to come up with a trans-disciplinary term. Please post if you know of one.

My last 2 months have been on 4 hours of sleep per night.

Yeah it works, but God does it suck. This has occurred out of a need to get work done, so I wonder how many others found themselves conditioned in the same way.

I had good luck resetting my sleep patterns with regular exercise and Melatonin supplements. Melatonin makes it easier to fall asleep and stay asleep in a way that promotes rest.

Reply on news.ycombinator.com