What specific physiological challenge does a Soyuz land landing put unique stresses on compared to a splashdown?

Answer

The lower body joints and spines due to impact forces on land

Astronauts returning via Soyuz experience unique physical stresses on their lower body joints and spines because the hard landing on the ground subjects those unweighted areas to significant impact forces.

What specific physiological challenge does a Soyuz land landing put unique stresses on compared to a splashdown?

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