A 200 lb guy would be about 76 pounds. Here’s a few effects of that I think:
Bone loss, no need to support body weight, bones break down calcium and lose mass, increased risk of fractures.
Muscle atrophy: Muscles weaken when there's no need to use them to move around.
Cardiovascular deconditioning: The heart doesn't need to work as hard, which can lead to a weaker heart over time.
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