A 246-km continuous running race causes significant changes in bone metabolism.
BACKGROUND
Regular physical exercise exerts a favorable effect on the skeleton. However, excessive physical exercise may have detrimental effects. A low bone mineral density (BMD) has been registered in highly trained runners. The aim of the present study was to evaluate potential effects of the Spartathlon, an annual ultramarathon race of 246 km, on bone metabolism.


METHODS
Venous blood samples were taken before and within 15 min after the end of the race as well as three days after the start of the race. The following variables of bone metabolism were studied: osteocalcin (Oc), cross-linked-C-telopeptide of type I collagen (CTX), osteoprotegerin (OPG), and its ligand, receptor activator of nuclear factor kappaB ligand (RANKL).


RESULTS
Blood samples were taken from 18 runners (16 men and 2 women) at the three time points. The median time taken by the runners to complete the race was 32 h and 52 min. Serum levels of CTX were significantly increased immediately after the race as well as three days after the start of the race compared with the time prior to the race. Oc was transiently suppressed after the race. Serum levels of RANKL and OPG were increased three days after the start of the race compared to the time before the start of the race.


CONCLUSIONS
This study showed that an ultra-distance run of nearly 250 km induced changes in RANK/RANKL/OPG interaction, which suggests a transient uncoupling of bone metabolism, increased bone resorption, and suppressed bone formation.
Kerschan-Schindl
Katharina
K
Department of Physical Medicine and Rehabilitation, Medical University of Vienna, 1090 Vienna, Waehringer Guertel 18-20, Austria. Katharina.Kerschan-Schindl@meduniwien.ac.at
Thalmann
Markus
M
Sodeck
Gottfried H
GH
Skenderi
Katerina
K
Matalas
Antonia L
AL
Grampp
Stephan
S
Ebner
Christof
C
Pietschmann
Peter
P
D000328:Adult; D015415:Biomarkers / Q000097:blood; D001842:Bone and Bones / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D012420:Running / Q000502:physiology*; D013997:Time Factors
D015415:Biomarkers