Bone hormone boosts muscle performance during exercise but declines with age

When we exercise, our bones produce a hormone called osteocalcin that increases muscle performance, according to a new study. Osteocalcin naturally declines in humans as we age, beginning in women at age 30 and in men at age 50. This study describes the first bone-derived hormone known to affect exercise capacity and shows that osteocalcin injections can reverse the age-related exercise capacity decline in mice.