Effect of Body Iron Stores on Indices of Biosynthesis and Destruction of Red Blood Cells after a Single Session of Cycling Exercise.
- Author:
YUKARI KAWANO
;
AKIKO TOKASHIKI
;
YUKO MEKATA
;
KEIKO HAYASHI
;
HARUMI MATSUMOTO
;
IWAO UCHIYAMA
- Publication Type:Journal Article
- Keywords:
Red blood cells;
body iron stores;
osmotic fragility;
haptoglobin;
δ-aminolevulinate dehydratase;
single session of cycling exercise
- From:Japanese Journal of Physical Fitness and Sports Medicine
2002;51(2):225-234
- CountryJapan
- Language:English
-
Abstract:
Objectives : The present study investigates the effects of body iron stores upon indices of biosynthesis and destruction of red blood cells (RBC) induced by a single session of cycling exercise.
Design : Eight sedentary female students were divided into groups depending on their body iron stores : normal (C group, n=5) and iron deficient (D group, n=3) . Blood samples were collected at five time points of before (pre), immediately after (0 hours), then 1, 3 and 6 hours after exercise (248±31 kcal, 70% V02 peak level) . Osmotic fragility and serum haptoglobin (hp) concentration served as of for degradation, and δ-aminolevulinate dehydratase (ALAD) activity, erythropoietin concentration and number of reticulocytes served as indices of RBC biosynthesis.
Results : A single session of cycling exercise did not affect the level of RBC, hemoglobin, hematocrit, serum iron, ferritin, transferrin saturation, hp and osmotic fragility in either groups. The δ-ALAD activity increased at 3 (p<0.05) and 6 hours (p<0.01) after exercise compared with that at 0 hours in the C group. In contrast, δ -ALAD activity in the D group was significantly lower at 3 hours after exercise than that of C group (p<0.001) . Reticulocytes and erythropoietin concentration increased gradually in the C group after exercise, but not in the D group.
Conclusions : A single session of cycling exercise under our experimental conditions enhanced RBC biosynthesis indicated by δ -ALAD activity, whereas exercise-induced hemolysis was not evident. Body iron stores affect the δ -ALAD activity induced by a single bout of cycling exercise.
