Effect of spaceflight on the human body of muscle fibre prominent in muscles also change. Slow twitch endurance fibres used to maintain posture are replaced by fast twitch rapidly contracting fibres that are insufficient for any heavy labour. Advances in research on exercise, hormone supplements and medication may help maintain muscle and body mass. Bone metabolism also changes. Normally, bone is laid down in the direction of mechanical stress. However, in a microgravity environment there is very little mechanical stress. This results in a loss of bone tissue approximately 1.5% per month especially from the lower vertebrae, hip and femur. Due to microgravity and the decreased load
The Singing Bone learns of the younger brother's adventure. They then set out to deliver the body to the king, but on passing a bridge, the older kills the younger and buries his body beneath it. He takes the boar himself to the king and marries the king's daughter as prize. One day a shepherd sees a bone under the bridge and uses it to make a mouthpiece for a horn, which sings of the brother's fate: "Ah! Dear shepherd, you are blowing your horn With one of my bones, which night and morn Lie still unburied, beneath the wave Where I was