Microgravity doesn’t confine fluids like sitting…riding a desk all day.

Rather, it liberates fluids, and that might spike blood pressure.

Over at the Cosmoquest Forum, is a former physician from the UK. https://oikofuge.com/

His thoughts
https://forum.cosmoquest.org/forum/science-and-space/science-and-technology/135097-it-makes-your-blood-boil?p=3341531#post3341531

The skin tight suits we hear about–you may be just asking for crush and compartment syndrome. That’s how Miles O’Brien lost an arm.

Ronaldus Magnus: As a regular reader of BtB, you read that here. See:

Vast unveils its proposed full space station concept

Update on Vast’s space station plans

https://www.frontiersin.org/files/Articles/1163346/fncir-17-1163346-HTML/image_m/fncir-17-1163346-g001.jpg

Blackwing1: Immobility is not an issue on long space mission. First of all, as you note, they can move around. They aren’t confined to a chair. And weightlessness expands space. Look up. There is a lot of unused cubic footage above our heads we never really use. In space, that all becomes useful and is used.

And exercise is not only a good idea, it is required. To make sure their muscles and bones and cardio-vascular system don’t decline during long missions, astronauts are required to exercise about three hours ever day, using a variety of treadmill devises created for weightlessness.

However, the nature of weightlessness is very similar to bed rest or the immobility of airplane passengers, so your noting of a link here is quite correct.

https://pmc.ncbi.nlm.nih.gov/articles/PMC8412040/

One of the lines from this that stood out for me was, “This syndrome results from several factors related to the aircraft cabin (immobilization, hypobaric hypoxia, and low humidity) and to the passenger (such as obesity, thrombophilia, oral contraceptive use, hormone replacement therapy, and cancer) that act together, predisposing an individual to excessive blood coagulation, which can result in VTE”.

Obviously people, both men and women, selected for space flight should be in much better physical shape than those of us of the common ruck. So the risk factors noted for things like obesity (and I’d guess high blood pressure) probably don’t apply But I’m wondering what the atmosphere in places like the ISS is like. What’s the atmospheric pressure? What’s the relative humidity?

But with air passenger flights it seems that the biggest single factor is immobility in a single bad position that leads to vein leakage near the knees. That’s got to be a least one simple problem that can be alleviated during an extended tour of a space station: Exercise. Just move around and have some fun in zero-G (or as it’s called now, “microgravity”). Do some simple gymnastics and tumbling in place…move your arms and legs, spin, heck spend 15 minutes a day just having fun and write it off as physical conditioning. Use the exercycle for your legs often, and I hope they’ve got something similar for arms.

I’m hoping that future space stations and habitats will include a space partially dedicated to these kinds of activities because, dang it, space exploration should also be FUN.

“A University of Queensland study has shown that a deadly scorpion’s venom carries an extra biochemical sting that could be used to guide future medical treatments and tests. The paper is published in the journal Biochimie. “This work shows that some scorpions can biochemically hijack core components of the clotting cascade in a way we typically associate with some snake venoms. Being novel, they may hold the key to saving lives through controlling blood loss during surgery or after injury.””