While this may or may not be true hacker news is particularly susceptible to exercise fads with unconventional scientific explanations.
I think it'd be easier to convince the readership of HN to lose weight and get fit by eating live maggots whilst suspended upside down in a vat of soylent than to just show up to the gym 3x a week.
The most important way to get fit is to show up and do work. The virtues of a programmer (laziness, impatience, hubris), are the opposite of what you need to succeed at physical fitness.
The writer's about page says:
> Todd’s philosophy of Hormetism is the result of years of personal investigation into the role of moderate stress in adaptation, as applied to health, nutrition, rehabilitation and psychology.
Hormetism is the idea that a low dose of a chemical can induce a response that's the opposite of the response seen at a high dose [1].
Hormetism is, to say the least, very controversial. It is at best a seldom observed, poorly understood phenomena that's important for the biological role of nitric oxide and a few other chemicals. At worst, it's like homeopathy: quacktacular pseudoscience. So take this article with a grain of salt.
Simple physics analysis
Almost all of the energy we get from food is used to heat our bodies, mostly indirectly via our liver, spleen and brain. [ https://www.boundless.com/physics/textbooks/624/work-and-ene... ]
A 40 degC person exposed to 0 degC air would lose heat at twice the rate of normal (40 degC person in 20 degC air). That's because convective heat flow rate is roughly proportional to temperature difference. All that heat has to be made up for by the body's metabolism. So you would burn calories at nearly twice the rate you would normally. It doesn't matter if it comes from brown fat, shivering, waste heat from your brain, or some other process, as long as it's internal to your body, it's taking energy that would otherwise not have been used.
A shower in 0 degC water could be on the order of 100 times more effective than 0 degC air, so you could get the same value from a shorter exposure. [ http://www.engineersedge.com/heat_transfer/convective_heat_t... ]
A cold shower for a couple of minutes a day (0.1 % of your life) would be equivalent to cold air for a couple of hours (10% of your life). That's about 10% more energy used than otherwise. So it sounds like even from a simple heat transfer perspective, cold showers must be effective at losing weight, as long as you don't compensate for that some other way like feeling more hungry afterwards :P
One thing I know that cold, exercise, and loud noises all have in common is that the body responds to them by producing adrenaline. People are told by nutritionists to take compounds like tyrosine to make up for the essential nutrients (i.e. phenylalanine) that sustained adrenaline production uses up, if they work in an environment with frequent "shocks" of any of the above types.
I do wonder if actually being in such a phenylalanine-depleted state (which is then also a tyrosine-depleted, phenylethylamine-depleted, L-DOPA-depleted, dopamine-depleted, adrenaline-depleted, and norepinephrine-depleted state) has any long-term effects on the body, which might even be positive. Goodness knows it certainly makes you want to sleep for a week.
(Come to think of it, an interesting question would be whether people with phenylketonuria who grew up on a compensatory dietary-restriction regimen low in phenylalanine—thus causing such sustained deficiencies of all the above—have any physiological differences to people without phenylketonuria.)
I've been taking cold showers for years, it gives such a good kick in the morning it's MUCH more efficient than coffee to get you from that lethargic state you can get in the morning to full-speed. Oh and if you had a heavy evening the night before, it's also a good way to remove the potential lingering headache you woke up with :-)
It does take a little willpower to get in, but the 'cold' effect lasts about a second; I no longer even have the unrestrained strong shiver I use to have due to the thermal shock.
Oh, and even in really cold water, I can stay there for quite a while, wash my hair etc. The sign that I've been there too long is when the top of my feet start to hurt a little.
Once you get out, metabolism is at full speed and you'll pretty quickly feel very, very warm (while staying outwardly cold for a while).
Only downside I know of is that I'll sometime feel too warm when I get in the office, as the metabolism goes overboard a bit.
My wife doesn't understand how I do it, she calls me 'glaconman' (french version of iceman) since I'm definitely not getting any cuddles for the next 20 minutes or so -- but well, it does work very well for me...
Also of interest may be the Mammalian Diving Reflex (https://en.wikipedia.org/wiki/Mammalian_diving_reflex) - Exposing your face to cold water and holding your breath can induce bradycardia (slowing of pulse), dropping it by 10-20 BPM.
In my experience, it leaves me with a sense of calm and general body-relaxation similar to how I feel 30-60 minutes after cardio workouts.
The homepage of this website is currently encouraging "natural" correction of myopia via slightly incorrect prescription and intentional straining. Most of the evidence I'm aware of (see references in e.g. http://www.bbc.com/future/story/20140513-do-glasses-weaken-y...) concludes that this makes things worse. My reaction to such things (especially when focussed on natural methods) tends to be distrusting objectivity.
Article is from 2014.
Also this guy thinks he has the solution to back pain and bad vision as well, so I would take all of his solutions with a "not verified by actual scientific studies" grain of salt.
Interesting. The article reads a bit like bro-science but there are plenty of references to scientific studies... I'll be curious to see whether 'cold therapy' starts appearing as a buzz word in weight loss treatments.
I have been on cold showers for almost a year now. Can't imagine going back to warm showers, even in the dead of the winter. The coldest shower I took was perhaps in Switzerland in December - I lasted for a couple of minutes or so in the shower. It was a fabulous experience nonetheless. Why take a cold shower ? I was spending way too much time in hot showers, almost 20-30 minutes. Criminal waste of time and water. Am not sure about the benefits, haven't noticed anything change in my body, but it's a great feeling to come out of an icy cold shower. Suddenly, the world feels warmer :)
Cold showers remind me of my experience in a Japanese bathhouse in Kyoto. At first, the hot baths are way too hot and the cold bath is absolutely freezing. But, if you power through it, the results are amazing. The process of (rinse > hot bath > cold bath) repeated over and over again was incredibly calming.
It ended up being one of my favorite things about Japan, and I spent 2-3 hours there everyday during my week in Kyoto.
I wrote about my experience with cold showers here before: https://news.ycombinator.com/item?id=8808859
490 days later, I'm still using cold water only. Except for ears: switched to using warm water when experienced some buzzing in one ear during last winter. I've upped my game by adding snow/ice baths during the winter. Since last autumn I have added daily HIIT - 10-15 mins of advanced body-weight exercises with 20 sec. rest intervals.
Now, how it affects my weight. Since the last time I wrote about it, I've actually begun to follow my weight numbers. Back at the time I was about 84kg. Cold showers alone, with some gym here and there didn't do much for weight: it went down to 83 sometimes, but bounced back to 84 later. Yet, I must say, I was well into the practice by that time, and few years before I could weight as high as 88 kgs. So, perhaps, cold showers did lower my weight somewhat without my notice. Adding HIIT gave a steady weight loss, albeit a slow one: three months into I lost only 2-3kgs. It is possible that HIIT burned more fat yet balanced weight by adding lean mass: some muscles are bigger now. Mind you, all that time weight was of no concern to me: followed it just out of curiosity. Last January though, my old trauma reminded about itself and I needed to lose weight. Since I was already doing most of the recommended stuff, I just cut on calories by completely removing sugar and keeping 12 hour window for eating. In one month I lost about 6kgs going to 76-77kgs and decided to keep it their by increasing calories. TL;DR: Cutting calories is the fastest way to lose weight, neither cold-showers, nor HIIT can compete with it in short term.
On the upside, both cold showers and HIIT are downright pleasure to do once you get addicted to them. I do HIIT after the work before evening meal, at about 5 - 6PM, follow it with a cold shower and feel full and energetic as if I've just waken up in the morning.
I like cold showers, and hot ones. I can never have a shower hot enough though, and getting out always is chilling. Whereas once you get out a cold shower, you only feel warmer. Preferably you don't want to leave the cold for freezing. I swam in a mountain stream late autumn last year (in the UK). It was so icy entering the stream, I thought it was never going to happen. After a few attempts and acclimatisation I was happily immersed. A little sun on the skin afterwards left me totally re-energised and awake. So just stick with it if you want to give it a go. Much like a cold shower, it's initially shocking, but becomes pleasurable. The human body is quite odd!
I'm into my second year of extreme Scottish showers -- first 5 minutes as hot as I can stand (and keep turning it up as I get used to the temp) ... last 5 minutes as cold as it goes. I expect there are legitimate physical health benefits; however, for me, the main benefit is the challenge & discipline of it, of stepping out of the shower thinking that the hardest thing I'll do today may already be behind me.
I'm exclusively showering cold now for more than a year. If I recall correctly one of the reasons was a VICE documentary on Wim Hof - that quite impressed me - though after a while I came to the conclusion that he is mostly well marketed (by his son - who he refers to as the biggest asshole he knows - https://youtu.be/VaMjhwFE1Zw?t=1311) and that most claims are rather blown out of proportion.
For example his scientific research on suppressing immune response to an infection is sold as a medical revolution while it has absolutely no practical value - if you think about it - quite the opposite as an immune response is usually something rather useful.
Anyway - I think it is worth it for several obvious reasons:
- it's definitely very refreshing!
- it helps waking up a lot
- it is a simple way to train discipline
- it's less stressful to skin than hot water
- it's nice to know that I am not depending on hot water
I did it for over year. It's still uncomfortable as I remembered that I always need to mentally get ready. My upper arms, especially triceps, are the most painful, coldest body parts when showered in cold water. I'm not sure why. During winter, I literally had to jump up and down, screaming to withstand the absolutely torturing coldness for the first five seconds. It gets a little better after that. I couldn't never take cold shower too long before the freezing water penetrating the skin and shivering the bone. That's when I know it's time to finish and get out.
I started to shower cold (actually first warm, then cold, then "neutral") every day when I was 9. I'm 30 now, so 21 years of that :).
I almost never feel cold, when I do i'm sick or very tired.
I do martial arts and I gain muscles very very easily, so maybe that's because of that?
And all my blood values have always been in the optimal range, except cholesterol which is always a bit too high (runs in the family).
An alternative for people in colder climates: just wear less clothing day-to-day. I generally wear one layer fewer than people around me. It really doesn't take long for the body to acclimate to it to the point it's no longer uncomfortable.
I love my hot showers too much to give them up, so this seems preferable.
I ran D1 track in college and our strength coach advised us to take cold showers before lifting as a way of warming up and calming down, but mostly calming down. He said it was a good idea before races too.
The guy was absolutely ripped so I'd believe what he says, and he usually backed it up with studies.
There is a lot of controversy surrounding Irisin.
http://blogs.sciencemag.org/pipeline/?s=Irisin
Quotes Peter Attia? He isn't a researcher.
I would certainly take a lot of cold showers if I didn't have to be conscious during the shower.
How cold should be cold showers ?
Please refrain from using abusive terms here on this forum.
Wim Hof people Wim Hof
I started taking cold showers about 3 months ago when my cofounder challenged my statement of: "Why don't more people eat healthy and exercise? It sucks at the beginning but it just keeps getting better." With the statement of "for the same reason you don't take cold showers." I'd never heard that cold showers were good for you and after validating his claims, I gave myself two weeks to get used to as-cold-as-possible showers. After about ten days it started being less painful, and now I can barely imagine going back. Yes the 3 degree Celsius showers still kinda suck; but they wake you up and they make the towel afterwards so warm and inviting. They make you hardened to the outdoor cold and they make you not need that first coffee in the morning.
If fixing diet and exercise are number 1 and number 2 to being a happier human. I'd put fixing the person you're dating at number 3, the people you're friends with at number 4, and the temperatures of the showers you take at number 5. A+ / 5 star - would have my cofounder challenge me again.