title: Lactic response in sickle cell trait carriers in comparison with subjects with normal hemoglobin.
abstract: OBJECTIVE
  The objective of this study was to assess lactic response (mmol/L) during incremental exercise in a specific population of men and women with sickle cell trait.
  
  
  METHODS
  Athletic men and women from the French West Indies showing no anemia and/or alpha thalassemia.
  
  
  METHODS
  Anemia was ruled out by hemoglobin level, and alpha thalassemia was ruled out by hemoglobin S percentage with concomitant hemoglobin level and mean corpuscular volume. Comparison was made with control subjects with normal hemoglobin, matched for physical fitness, anthropometric data, and sex. All subjects performed an incremental exercise test using a cycle ergometer. Peak oxygen uptake (mL/min) was predicted from an equation at peak exercise. Heart rate (beats/min) was noted continuously, and blood samples were collected for lactic response determination every minute during the incremental exercise test and at 1, 3, and 5 minutes of recovery.
  
  
  RESULTS
  Comparison of peak oxygen uptake and heart rate values showed no significant differences in subjects with sickle cell trait versus control subjects during the incremental exercise test. In contrast, analysis of variance revealed significantly lower lactic response time courses during the incremental exercise test and at peak exercise (p < 0.05) in the sickle cell trait group, whereas the heart rate time course was lower during recovery (p < 0.05).
  
  
  CONCLUSIONS
  We conclude that the lower lactic response exhibited by subjects with sickle cell trait during incremental exercise was the result of an adaptive process in red blood cells in relation to either lower lactate production or greater lactate uptake capability than in individuals with normal hemoglobin.
authors.affiliation: Université des Antilles et de la Guyane, Pinte á Pitre, Guadeloupe.
authors.forename: Fagnété
authors.initials: F
authors.lastname: Sara
authors.forename: Marie-Dominique
authors.initials: MD
authors.lastname: Hardy-Dessources
authors.forename: Bruno
authors.initials: B
authors.lastname: Voltaire
authors.forename: Maryse
authors.initials: M
authors.lastname: Etienne-Julan
authors.forename: Olivier
authors.initials: O
authors.lastname: Hue
mesh_terms: D000222:Adaptation, Physiological; D000328:Adult; D004912:Erythrocytes / Q000502:physiology; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D005260:Female; D006339:Heart Rate; D006801:Humans; D019344:Lactic Acid / Q000097:blood*; D008297:Male; D010101:Oxygen Consumption; D010809:Physical Fitness / Q000502:physiology; D012805:Sickle Cell Trait / Q000097:blood*
chemical_list: D019344:Lactic Acid