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
What's Bred in the Bone What's Bred in the Bone What's Bred in the Bone is the second novel in the Canadian writer Robertson Davies' Cornish Trilogy. It is the life story of Francis or Frank Cornish, whose death and will were the starting point for the first novel, "The Rebel Angels". After a brief framing scene among characters from "The Rebel Angels", the novel turns to a conversation between the Recording Angel and the daimon in charge of Cornish's life. The main part of the book is that life as narrated by the Recording Angel, interspersed with comments in which the daimon explains how