Iron status of highly active adolescents: evidence of depleted iron stores in gymnasts.
Much attention has focused on the nutrition and hematological profile of female athletes, especially gymnasts. The few studies on iron status of male adolescent athletes found a low incidence of iron deficiency. The present studies investigated the iron status of male and female gymnasts (G) and compared it with athletes of other sports. Subjects were 68 elite athletes (43 M, 25F) ages 12-18, of four sports: gymnasts (11M,12F), swimmers (11M,6F), tennis players (10M,4F), and table tennis players (11M,3F). All lived in the national center for gifted athletes, trained over 25 hr a week, ate in the same dining room, and shared a similar life style. Mean levels of hemoglobin (Hb), red blood cell indexes, serum ferritin, serum iron, and transferrin were measured in venous blood. There was no difference in mean Rb among gymnasts (G) and nongymnasts (NG). However Hb was less than 14g/dL in 45% of MG vs. only 25% in NG, and less than 13g/dL in 25% of premenarcheal FG vs. 15% in NG. Low transferrin saturation (<20%) was detected in 18% of MG and 25% of FG vs. 6% and 8% in male and female NG, respectively (p<.05). The percentage of males suffering from low ferritin level (<20 ng/ml) was twice as high in G (36%) vs. NG(19%), and about 30% in all females. In summary, iron stores were consistently lower in MG vs. NG. Adolescent athletes of both genders, G in particular, are prone to nonanemic iron deficiency, which might compromise their health and athletic performance.
Ribstein Center for Sport Medicine Sciences and Research, Wingate Institute, Netanya, Israel.
N W
NW
Constantini
A
A
Eliakim
L
L
Zigel
M
M
Yaaron
B
B
Falk
D000293:Adolescent; D017195:Adolescent Nutritional Physiological Phenomena; D000704:Analysis of Variance; D002648:Child; D002664:Child Nutritional Physiological Phenomena; D004032:Diet; D004906:Erythrocyte Count; D004909:Erythrocyte Indices; D005260:Female; D005293:Ferritins / Q000097:blood; D006173:Gymnastics / Q000502:physiology*; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D007501:Iron / Q000097:blood*; D000090463:Iron Deficiencies; D007557:Israel; D008019:Life Style; D008297:Male; D008572:Menarche / Q000502:physiology; D012737:Sex Factors; D013177:Sports / Q000502:physiology; D013550:Swimming / Q000502:physiology; D013715:Tennis / Q000502:physiology; D014168:Transferrin / Q000032:analysis
D006454:Hemoglobins; D014168:Transferrin; D005293:Ferritins; D007501:Iron