[rzerowan]

To expand on that - there are many body systems that depend almost entirely on the 1g glodilocks zone. Lymphatic systems movt , venous blood returning deox blood to the heart and even some digestive processes. Keenly dependent on a g value that allows proper muscle tone/function to the systems at play. Too little or too much and and human life becomes non-viable. Throw in the effect of ping ponging between microgravity and 1g and the issues multiply.