Space crews **transition through different gravity fields**, which have significant impacts on their health. In 6 month trek between planets, crews will be weightless. On Mars, crews will be in 1/3 of earth’s gravity Effects: - distortion of spatial orientation, head-eye and hand-eye coordination, balanace and locomation (see [[Spaceflight Associated Neuro-ocular Syndrome]]) - Post-flight orthostatic intolerance, which occurs when astronauts can't maintain blood pressure when standing, leading to fainting and lightheadedness - Circumference changes in chest, waist, and limbs. - Without earth’s gravity, weight bearing bones *lose 1 - 1.5% of mineral denisity per month.* This is called **unloading**. ##### Microgravity - Microgravity causes fluids to shift upward in the body and leave the legs. This results in an **upward shift of the center of mass** for the whole body and a loss of mass in the leg segments. - Due to spinal decompression and lengthening, **height increases approximately 3%** - Without proper diet and exercise, astronauts lose muscle mass in microgravity much faster. Fluids in the body shift upwards which puts pressure on eyes and may cause vision problems - **Absence of a Fixed Vertical Orientation** - Recognition of familiar objects, faces, and areas (e.g., workstation) is poor when viewed from an orientation significantly different from the established vertical. The **viewer must be oriented within approximately 45 degrees of this vertical** to perceive the surroundings in a relatively normal fashion. - Kidney stones are also more likely due to dehydration and increased excretion of calcium from bones - Puffy Face Chicken Leg syndrome = space microgravity result in increased pressure in skull resulting in a changes vision. Vision gets worse the longer astonauts are there - Shift in perceived colors and a reduction in contrast sensitivity **Solutions** - Functional task testing to improve balance control after landing on a gravitational surface - Fine motor skills testing is done to detect changes in the ability of astonauts to interact with computer based devices - Compression cuffs used to keep blood in lower extremities to counteract fluid shifts - Lower body negative pressure device could help draw fluids from head into the legs - Potassium citrate may combate change that could increase risk of kidney stones developing - Bisphosphonate medicines have been effective in preventing bone loss - Centrifuge artificial gravity could counter physiological effects of weightlessness #pn #Kareena Links to [[Space Food]] Practicalities: Necessary modifications to the form of food to enable eating and drinking in low gravity environments ![[Pasted image 20210830172414.png]]