HAEMATOLOGICAL HAEMATOLOGICAL PARAMETERS IN PARAMETERS IN

SWIMMERSSWIMMERS

Daniel Gerrard BMedLabSciDaniel Gerrard BMedLabSci

David Gerrard MBChBDavid Gerrard MBChB

Dunedin School of Medicine, U of Dunedin School of Medicine, U of OtagoOtago

New ZealandNew Zealand

APPLIED SCIENCE APPLIED SCIENCE CLINICAL INTERFACECLINICAL INTERFACE

““Coaches and Coaches and scientists seeking scientists seeking measures of enhanced measures of enhanced performance balanced performance balanced by clinicians searching by clinicians searching for indicators of for indicators of failing adaptation and failing adaptation and consequent ill-consequent ill-health...”health...”

INTRODUCTORY COMMENTSINTRODUCTORY COMMENTS

Endurance Endurance trainingtraining

Red Blood Red Blood Cell (RBC) Cell (RBC) genesis, genesis, turnoverturnover

AnaemiaAnaemia Haptoglobin Haptoglobin

functionfunction

POSTULATEPOSTULATE

““That endurance-trained athletes show That endurance-trained athletes show haematological evidence of enhanced haematological evidence of enhanced oxygen transport.”oxygen transport.”

POSTULATEPOSTULATE

““That endurance training is That endurance training is characterised by a younger RBC characterised by a younger RBC

population”population”

STUDY AIMSSTUDY AIMS

To establish haematological To establish haematological parameters for two, age-dependent parameters for two, age-dependent cohorts of male swimmers & cohorts of male swimmers & compare these with established compare these with established laboratory normal values.laboratory normal values.

SUBJECTSSUBJECTS Endurance-trained Endurance-trained

malesmales Masters group “M” Masters group “M”

(n=11, mean age (n=11, mean age 58yrs)58yrs)

Youth group “Y” Youth group “Y” (n=20, mean age (n=20, mean age 22.1yrs)22.1yrs)

Pooled group Pooled group “M+Y” (n=31, “M+Y” (n=31, mean age 35yrs)mean age 35yrs)

METHODS METHODS Venous blood Venous blood

samples drawnsamples drawn Participants Participants

recruited from recruited from local swim squads.local swim squads.

Endurance training Endurance training criteria appliedcriteria applied

University of University of Otago ethical Otago ethical approval approval

HAEMATOLOGICAL HAEMATOLOGICAL MEASURES MEASURES

Venous samplesVenous samples RBC indices RBC indices Hb concentrationHb concentration HaematocritHaematocrit TWCCTWCC Reticulocyte Reticulocyte

countcount Serum Serum

HaptoglobinHaptoglobin

RESULTSRESULTS Significant inter-age Significant inter-age

differences differences Compared to “normal” Compared to “normal”

values there was:values there was: Decrease in RBC Decrease in RBC

parameters, parameters, Hb,Hct,haptoglobin Hb,Hct,haptoglobin levelslevels

Increase in MCV Increase in MCV (“runners’ (“runners’ macrocytosis”)macrocytosis”)

Reduced reticulocytesReduced reticulocytes

ENDURANCE TRAININGENDURANCE TRAINING (1)(1)

Physiological Physiological adaptations…adaptations…

Influence on Influence on cardio-respiratory cardio-respiratory efficiency… efficiency…

Improved Improved efficiency of efficiency of oxygen delivery oxygen delivery

ENDURANCE TRAINING ENDURANCE TRAINING (2)(2)

Mechanical trauma Mechanical trauma to RBCsto RBCs

Altered cell Altered cell membrane fragilitymembrane fragility

HaemolysisHaemolysis Reduced Reduced

Haptoglobin levelsHaptoglobin levels Younger RBC Younger RBC

populationpopulation

RED BLOOD CELL ROLERED BLOOD CELL ROLE OO22 transport transport Haemoglobin Haemoglobin

(Hb)(Hb) 4 globin subunits 4 globin subunits

(alpha + beta)(alpha + beta) Porphyrin Porphyrin

molecule = Haemmolecule = Haem Binds ironBinds iron 4 haeme 4 haeme

molecules per Hb molecules per Hb moleculemolecule

RBC PRODUCTIONRBC PRODUCTION

Regulated by Regulated by Erythropoietin (EPO)Erythropoietin (EPO)

Reticulocytes from bone Reticulocytes from bone marrowmarrow

RBC lifespan 117.3 daysRBC lifespan 117.3 days 1% replaced daily1% replaced daily Haemolysis = Haemolysis =

erythropoiesiserythropoiesis Constant RBC massConstant RBC mass

INFLUENCES on RBCsINFLUENCES on RBCs Metabolic, Metabolic,

mechanical, oxidative mechanical, oxidative stressesstresses

Reduced lifespanReduced lifespan Increased immature Increased immature

population of RBCspopulation of RBCs Anaemia (hypoxia) Anaemia (hypoxia)

Destruction > Destruction > synthesissynthesis

? Optimal ? Optimal haematological haematological parameters for parameters for athletesathletes

ANAEMIAANAEMIA Decrease in RBC Decrease in RBC

massmass Link with diminished Link with diminished

athletic performanceathletic performance Dilutional anaemiaDilutional anaemia Intravascular Intravascular

haemolysis haemolysis (mechanical)(mechanical)

Dietary iron Dietary iron (nutritional)(nutritional)

Haeme & non-haeme Haeme & non-haeme sourcessources

HAPTOGLOBINHAPTOGLOBIN Acute phase plasma Acute phase plasma

proteinprotein Binds Hb from Binds Hb from

haemolysed RBCshaemolysed RBCs Hapt-Hb complexesHapt-Hb complexes Hepatic removalHepatic removal Resultant decreased Resultant decreased

serum Hapt levelsserum Hapt levels Inversely related to Inversely related to

intravascular intravascular haemolysishaemolysis

CONCLUSIONS (1)CONCLUSIONS (1)

That the dilutional anaemia of That the dilutional anaemia of exercise is the result of more than exercise is the result of more than a simple expanded plasma volume.a simple expanded plasma volume.

CONCLUSIONS (2)CONCLUSIONS (2)

That rising haptoglobin levels That rising haptoglobin levels may provide a useful index of may provide a useful index of endurance training.endurance training.

CONCLUSIONS (3)CONCLUSIONS (3)

An increased RBC turnover may explain An increased RBC turnover may explain the association between a younger RBC the association between a younger RBC population & increased oxygen delivery.population & increased oxygen delivery.

CONCLUSIONS (4)CONCLUSIONS (4)

Further research is indicated to determine Further research is indicated to determine the effects of endurance training & age on the effects of endurance training & age on haematological parameters.haematological parameters.

THANK YOUTHANK YOU

FOR YOUR ATTENTIONFOR YOUR ATTENTION