K. Thorsen et al., EFFECTS OF MODERATE ENDURANCE EXERCISE ON CALCIUM, PARATHYROID-HORMONE, AND MARKERS OF BONE METABOLISM IN YOUNG-WOMEN, Calcified tissue international, 60(1), 1997, pp. 16-20
We investigated the short-term (1 hour-3 days) effects of a 45 minute
run on calcium, parathyroid hormone, the carboxyterminal propeptide of
type I procollagen (PICP), and the immunoactive carboxyterminal telop
eptide of type I collagen in serum (ICTP) in young females. Fourteen h
ealthy young women, aged 25.2 +/- 0.6 years (mean +/- SEM) with regula
r menstruations, participated. The test was outdoor jogging for 45 min
utes at an intensity of 50% of VO2 max. Blood samples were collected 1
5 minutes before the test and 1, 24, and 72 hours after the test. The
measured values were adjusted for changes in plasma volume. A signific
ant decrease of ionized calcium was observed at 1 hour (P < 0.001) and
72 hours (P < 0.05) and a significant increase of parathyroid hormone
(PTH) was noted 74 (P < 0.01) and 72 hours (P < 0.05) after the test.
A significant decrease of PICP at I hour (P < 0.05) was followed by a
n increase after 24 (P < 0.01) and 72 hours (P < 0.001) and a signific
ant increase in ICTP was noted at 24 and 72 hours (P < 0.05). A strong
positive correlation was found between serum levels of PICP and ICTP
(r = 0.55-0.84; P < 0.05) throughout the experiment. In conclusion, yo
ung females showed biochemical signs of increased bone collagen turnov
er and altered homeostasis of calcium and PTH after a single bout of m
oderate endurance exercise.