Maximum weight for astronaut/space tourist

[Camacha]

It's possible to be overweight and healthy, just as it's possible to be very old and healthy. While there is definitely a correlation between being overweight and being unhealthy, they're not inextricably linked.

It is possible in theory, but increasingly unlikely. There are smokers that grow really old without trouble, but the sad truth is that most die early and/or die slow, extended and horrible deaths. Both smoking and lots of fat strain your whole body a lot.

Actually motivation has little to do with it. If you're...very big, the most you can hope to reasonably do is maintain your fitness level (which is pretty separate from the amount of body fat you store), and manage your weight so that you don't become morbidly obese. Actually getting rid of weight is nigh-on-impossible; most people after losing weight gain it again very fast, sometimes even before they're "done" dieting.

Sounds like an excuse to me. I am not pretending it is easy, but (nigh-on-)impossible it is not. If you truly go all-in and preferably get some help, there is very little to stop the change.

Edited June 12, 2014 by Camacha

[Camacha]

Even considerable exercise and dieting can result in a rebound when someone stops the diet, even if they continue exercise.

That is the thing, you should not start and stop diets, you should make changes to your life. If you are fat, you generally made some dodgy choices in the past and probably picked up some bad habits. Pretending to do/be healthy for a while will only have pretend results, but making real changes will have long term results.

And yes, those kinds of changes can be incredibly hard, but that is up to the one who wants to make them. They have to make them.

[Javster]

Your weight in space is 0, so why would you pay more than others who weight the same? Mass on the other hand...

In space no one really cares. Getting there takes more fuel if you have a large payload

[Rickenbacker]

Of course you can lose weight, but dieting isn't the way to do it, as diets are at best a stopgap measure, and at worst scams. If you change your lifestyle so that you use more energy than you take in, you'll lose weight. This is true for everyone, everywhere.

[phoenix_ca]

Of course you can lose weight, but dieting isn't the way to do it, as diets are at best a stopgap measure, and at worst scams. If you change your lifestyle so that you use more energy than you take in, you'll lose weight. This is true for everyone, everywhere.

Sure (sorta), but it's hardly that simple, and some people are predisposed to storing more of that energy as fat. Men kinda get the lucky end of that by being predisposed to storing body fat around the vital organs, rather than in subcutaneous layers. The thing is, you can have a lower caloric intake than what you use every day, and doing so can actually be extremely detrimental to your overall health. Don't eat enough protein or vitamins and you'll be in far worse shape than you were before you started.

Eating less isn't as simple as just eating less. In fact its rather complex, something which people who don't have a solid grasp of biology can easily screw-up.

[Armchair Rocket Scientist]

As for cardiac performance in obese people in microgravity, it's entirely possible that it would be better in space than in Earth gravity, as there is not the weight upon the heart and vascular system. But as previously mentioned, the data is not yet there. The only way to find out would be to send fat people into space - so our first overweight space travelers are likely to be experiments.

The problem with that is some of the major physiological effects of long-term spaceflight are muscle atrophy (including the heart) and loss of bone density. These occur precisely because there isn't weight on the muscular, cardiovascular, and skeletal systems. The real danger isn't microgravity itself, it's going back to normal gravity. A human body in good condition is typically able to run and jump around, so all those systems are quite a bit stronger than is necessary to perform basic functions like pumping blood to the brain while standing up. A body in poor condition has a narrower safety margin.

[Camacha]

Of course you can lose weight, but dieting isn't the way to do it, as diets are at best a stopgap measure, and at worst scams. If you change your lifestyle so that you use more energy than you take in, you'll lose weight. This is true for everyone, everywhere.

That is pretty much what I meant. People treat diets as if they are antibiotic treatments - do one and you are cured. It does not work that way. You have to make structural changes to what you eat and what you do. Permanent changes. That is why exotic diets do not work, they are way too hard to maintain over an extended period of time. You have to change your diet, not do a diet.

Of course, energy expenditure is not everything when it comes to being healthy. Using more energy (excercise or just daily activities) and taking in less energy (eating less food, or less caloric food) helps losing weight. But general health is also a factor. Limiting yourself to two packs of chips a day is not going to make you healthy. You will need to eat decent meals at regular intervals. Undereating is actually making your body go into a saving mode, storing every shred of what you take in. Make sure you get your vitamins and minerals, as they help your body to deal with the burden it is under.

People always pretend it is some kind of rocket science, but it is really not that hard.

[Nuke]

So, the only thing that's keeping you from getting fit is that you haven't already been selected as an astronaut candidate?

i dont like change, unless its the planet line of my address.

The problem with that is some of the major physiological effects of long-term spaceflight are muscle atrophy (including the heart) and loss of bone density. These occur precisely because there isn't weight on the muscular, cardiovascular, and skeletal systems. The real danger isn't microgravity itself, it's going back to normal gravity. A human body in good condition is typically able to run and jump around, so all those systems are quite a bit stronger than is necessary to perform basic functions like pumping blood to the brain while standing up. A body in poor condition has a narrower safety margin.

i would be less concerned with going to space, and living in space, than i would be with returning to earth. after space has degraded the systems of the body of an already unhealthy individual and then putting them through the shock of re-entry and living under a gravity well. you might have a heart attack 3 steps out of the lander before you get a chance to brag about going to space.

Edited June 12, 2014 by Nuke

[Camacha]

i dont like change, unless its the planet line of my address.

Dying is a hell of a change