Effects of zinc supplementation on vertebral and femoral bone mass in rats on strenuous treadmill training exercise.
The hypothesis that a zinc (Zn) deficit may cause osteopenia in athletes is well founded. In rats exposed to strenuous exercise, we evaluated the effect of a zinc supplement on femoral and vertebral bone mass determined by dual-energy X-ray absorptiometry. Four lots of 93-day-old female Wistar rats were studied. A control group of 30 rats were not manipulated (Zn- Ex- group). The experimental group of 40 rats was fed a diet supplemented with an additional 20% of Zn/kg of feed; this group was divided into two groups of 20 rats each, one that did not exercise (Zn+ Ex-) and one that did (Zn+ Ex+). A group of 15 rats exercised but did not receive a zinc supplement (Zn- Ex+ group). Training consisted of treadmill running for 5 out of 7 days over an 11-week period. Initial speed, running time, and treadmill speed were increased gradually. Analysis of variance with the Bonferroni/Dunn test showed that the length, weight, bone mineral content (BMC), and bone mineral density (BMD) of the femur were less in the Zn- Ex+ group than in the others (p < 0.008), and the weight, BMC, and BMD of the fifth lumbar vertebra also were lower in the Zn- Ex+ group than in the others (p < 0.008). These findings confirm the adverse effects of strenuous exercise (treadmill running) on bone tissue in rats and the effectiveness of zinc supplementation in preventing it.
Seco
C
C
Department of Medicine, University de Alcalá de Henares, Madrid, Spain.
Revilla
M
M
Hernández
E R
ER
Gervás
J
J
González-Riola
J
J
Villa
L F
LF
Rico
H
H
D015502:Absorptiometry, Photon; D000818:Animals; D015519:Bone Density; D001851:Bone Diseases, Metabolic / Q000209:etiology; D019587:Dietary Supplements; D005260:Female; D006614:Hindlimb / Q000000981:diagnostic imaging; D010805:Physical Conditioning, Animal / Q000009:adverse effects; D051381:Rats; D017208:Rats, Wistar; D013131:Spine / Q000000981:diagnostic imaging; D015032:Zinc / Q000008:administration & dosage*
D015032:Zinc