Plasma Iron Concentration Changes Induced by High Impact Exercise after a Pre-exercise Carbohydrate Diet

高醣飲食與高撞擊運動對血漿鐵濃度之影響

湯馥君(Fu-Chun Tang)

《中華民國營養學會雜誌》 25卷4期 (2000/12) Pp. 219-225

https://doi.org/10.6691/JCNS.200012_25(4).0004

摘要

This study was conducted to investigate the effect of high impact exercise on the plasma iron concentration in college athletes fed a high carbohydrate (CHO) diet. Nineteen male college athletes completed two identical exhaustive exercise regimens (85% maximal oxygen consumption [VO2max], 10% grade) after a high CHO diet (~84% CHO, ~13 kcal/kg BW). Diet was given 60 min prior to exercise and ingested within 30 min. Exhaustion was determined by the measurements of maximal heart rate (HRmax), respiratory exchange ratio (RER), and plasma lactate concentration. Blood samples were taken before, during, and after the exercise program. In order to increase the sensitivity and accuracy of the statistical analysis, data from two identical exhaustive exercises were pooled. The plasma iron concentration increase significantly (p ＜ 0.05) during exhaustive stage and returned to its baseline (p ＜ 0.05) in the recovery stage, indicating that high impact exercise caused the rupture of erythrocytes and/or muscle cells, which would in turn affect the athlete’s exercise endurance. During the recovery stage, the clearance of plasma iron occurred rapidly, returning the homeostasis of the plasma iron concentration immediately. Urinary iron concentration, either pre- or post- exercise, was too low to be detected in this study. The results suggest that iron status is critical in athletes undergoing high impact exercise.

關鍵字

醣類 ； 運動 ； 鐵

並列摘要

This study was conducted to investigate the effect of high impact exercise on the plasma iron concentration in college athletes fed a high carbohydrate (CHO) diet. Nineteen male college athletes completed two identical exhaustive exercise regimens (85% maximal oxygen consumption [VO2max], 10% grade) after a high CHO diet (~84% CHO, ~13 kcal/kg BW). Diet was given 60 min prior to exercise and ingested within 30 min. Exhaustion was determined by the measurements of maximal heart rate (HRmax), respiratory exchange ratio (RER), and plasma lactate concentration. Blood samples were taken before, during, and after the exercise program. In order to increase the sensitivity and accuracy of the statistical analysis, data from two identical exhaustive exercises were pooled. The plasma iron concentration increase significantly (p ＜ 0.05) during exhaustive stage and returned to its baseline (p ＜ 0.05) in the recovery stage, indicating that high impact exercise caused the rupture of erythrocytes and/or muscle cells, which would in turn affect the athlete’s exercise endurance. During the recovery stage, the clearance of plasma iron occurred rapidly, returning the homeostasis of the plasma iron concentration immediately. Urinary iron concentration, either pre- or post- exercise, was too low to be detected in this study. The results suggest that iron status is critical in athletes undergoing high impact exercise.

並列關鍵字

carbohydrate ； exercise ； iron