title: Racial differences in hemoglobin and plasma volume variation: implications for muscle performance and recovery.
abstract: Objective:To examine the effect of race differences on sprint performance, Hemoglobin (Hb), Hematocrit (Ht) and plasma volume (PV) variation in response to repeated sprint exercise.Design:Thirty-six healthy, moderately trained men and women (20.8 ± 0.2 year-old) volunteered to participate in this study. They were allocated to one of the four groups according to their gender and race: Black men's group (BM,n= 9), White men's group (WM,n= 9), Black women's group (BW,n= 9) and White women's group (WW,n= 9). All participants performed the running-based anaerobic sprint test (RAST), which consists of six 35-m sprints with 10 s of recovery in-between. Six venous blood samples were collected to determine Hb, Ht and PV levels at rest, after warm-up, immediately post- and at 5, 15 and 30 min post-RAST. Blood lactate is also sampled during the 3rd minutes of recovery.Results:The best running time was significantly shorter (P= .002) in BW compared to WW. We have observed significantly higher Hb (P= .010) and Ht (P= .004) levels in BW compared to WW during the 5th minute of recovery. During RAST, the PV decreased significantly (P= .007) in WM only. Black groups had lower (P< .05) lactate levels compared to the white subjects. During recovery, PV increase was significantly (P= .003) higher in WW compared to BW during the 5th minute of recovery.Conclusion:This study demonstrated that sprint and repeated sprint performances were different between white and black women. Differences in anaerobic performance between the groups were associated with racial differences in lactate levels and blood count among women's group during recovery time. Hence, it is important to take into account this race-related difference in hematological parameters in responses to intense efforts.
authors.affiliation: a Research Laboratory 'Sport Performance Optimisation', National Center of Medicine and Science in Sport (CNMSS) , Tunis , Tunisia.
authors.forename: Maha
authors.identifier: 0000-0003-1832-409X
authors.initials: M
authors.lastname: Sellami
authors.affiliation: b Athelete Health and Performance (AHP) Research Center, Qatar Orthopaedic and Sports Medicine Hospital , Doha , Qatar.
authors.forename: Karim
authors.identifier: 0000-0001-9178-7678
authors.initials: K
authors.lastname: Chamari
authors.affiliation: c Faculty of Sciences - Bauru-SP, Department of Physical Education , UNESP - Univ Estadual Paulista , Brazil.
authors.forename: Alessandro Moura
authors.initials: AM
authors.lastname: Zagatto
authors.affiliation: d Laboratory of Movement, Sport and health Sciences (M2S), UFR APS, University of Rennes 2 , Rennes cedex , Rennes, France.
authors.forename: Wiem
authors.initials: W
authors.lastname: Kebsi
authors.affiliation: a Research Laboratory 'Sport Performance Optimisation', National Center of Medicine and Science in Sport (CNMSS) , Tunis , Tunisia.
authors.forename: Anis
authors.initials: A
authors.lastname: Chaouachi
authors.affiliation: d Laboratory of Movement, Sport and health Sciences (M2S), UFR APS, University of Rennes 2 , Rennes cedex , Rennes, France.
authors.forename: Hassane
authors.initials: H
authors.lastname: Zouhal
mesh_terms: D044383:Black People; D005260:Female; D006454:Hemoglobins / Q000032:analysis*; D006801:Humans; D019344:Lactic Acid / Q000097:blood; D008297:Male; D018482:Muscle, Skeletal / Q000502:physiology*; D010101:Oxygen Consumption; D005082:Physical Exertion / Q000502:physiology*; D010953:Plasma Volume; D044465:White People; D055815:Young Adult
chemical_list: D006454:Hemoglobins; D019344:Lactic Acid
keywords: Ethnicity; aerobic capacity; blood volume; dehydration; repeated intense efforts