Acute Haematological And Bilirubin Responses To Stress Of Sprint And Endurance Runs

Introduction
The mechanism for the "pathophysiological" phenomenon of sports anaemia is contentious. Sports anaemia has been
attributed to increase in red cell fragility and consequent haemolysis due to mechanical effects during the landing
phase of the foot while running [1]. Fragmentation haemolysis is reportedly caused by mechanical trauma to red
blood cells from turbulent blood flow [2]. We have previously reported that decrease in red blood cells count was
due to endurance exercise induced increase in plasma volume [3]. Acute increase in plasma volume has been
attributed to exercise induced increase in vascular proteins [4] and the concomitant oncotic pressure exerted by
these proteins [5]. Clinically, fragmentation haemolysis could be evaluated by showing unconjugated
hyperbilirubinaemia [2]. This study was designed to further investigate this issue. Two hypotheses were
formulated and tested in this study: (a) Neither sprint nor endurance run would have any significant effect on
haematological variables of haemoglobin (Hb), packed cell volume (PCV) and red cell count (RCC); (b) neither
sprint nor endurance run would have any significant effect on serium bilirubin.

Methods
Ten apparently healthy students (5 males, 5 females) of the National Institute for Sport (NIS), Surulere, Nigeria, gave
their informed consent and participated in this study. None of the subjects was on any medication that could alter the
normal metabolism of any of the variables under study [6]. The means (±SDs) of age, body mass and stature were
32.8 ± 9.52 yrs, 71.8 ± 8.88 kg and 177.32 ± 9.06 cm respectively for male subjects; and 28 ± 5.36 yrs, 62.4 ± 8.85 kg
and 164.06 ± 1.86 cm respectively for female subjects. A pre-test/post-test experimental design was employed in this
study. Subjects were bleeded in the basal state (after overnight fast) from the antecubital vein, with minimum stasis, for
pre-test values and immediately after each of 400 metres and 2.4 Km runs. Van Kampen and Zijlstra [7] method was
used in quantifying Hb. PCV was determined in Wintrobe microhaematocrit NH4 heparimised tube centrifuge
(Hawksley Microhaematocrit Centrifuge Machine, England) for 10 minutes. PCV was not corrected for trapped
plasma. Electronic counter (Coulter Models) was used for counting RCC [8]. Jendrassik and Grof [9] procedure was
employed in the determination of total bilirubin (Btotal) and conjugated bilirubin (Bcon). Unconjugated bilirubin (Buncon)
was derived by subtracting Bcon from Btotal. Each variable was determined twice and the mean computed. All variables
were determined at the Lagos University Teaching Hospital (LUTH), Idi-Araba, Lagos. The sprint (400m) and
endurance (2.4 Km) runs were performed in the main bowl of the National Stadium, Surulere, in the basal state between
09h00 and 11h00. Forty-eight hours elapsed between the two runs. Descriptive statistics (mean ± SD) and the t-test
(repeated measure) were employed in the treatment of data.

Results
The results of this study are shown in Table 1.
In the male subjects sprint run provoked a nonsignificant increase in Hb, PCV, RCC, Btotal and Bcon while Buncon did not
change. In the female subjects sprint run resulted in nonsignificant decrease in Hb, PCV, RCC and Bcon; Btotal and Buncon
revealed nonsignificant increase. 2.4 Km run resulted in nonsignificant decrease in Hb, PCV, RCC and nonsignificant
increase in Btotal and Bcon in male subjects. 2.4 Km run resuled in significant decrease in PCV (p ≤ 0.10) in female
subjects. Hb, RCC and Bcon were nonsignificantly reduced while Btotal and Buncon were nonsignificantly increased in the
female subjects. When the data were pooled, 2.4 Km run resulted in borderline significant reduction in PCV (p ≤ 0.05).
400m run did not produce any change in Buncon in male subjects while 2.4 Km run resulted in decrease in Buncon. There
was no difference in Buncon responses to 400m and 2.4 Km runs in female subjects. These results did not produce the
evidence to support that exercise haemolysis is the cause of sports anaemia. We accepted the two hypotheses in respect
of the variables under study with the exception of PCV. These results confirmed our previous findings on sports
anaemia [3]. We recommend, for further study in this area, red blood survival studies using Cr51 labelled red blood cells.

References
[1]. Brouns, F. (1993). Nutritional Needs of Athletes. Toronto: John Wiley and Sons.
[2]. Kampe, C.E. et al. (1998). Southern Medical Journal, 91, 970 - 972.
[3]. Agbonjinmi, A.P. et al. (2001). J. of Hum. Movt. Studies, 41, 141 -150..
[4]. Senay, L.C. Jnr.(1979). Med. Sci. Sports Exer., 11, 42.
[5]. Scatchard, G. et al. (1944). J. Chin. Invest., 23, 458
[6]. www.rwjhamilton.org/Atoz/Encyclopedia/article/003479.asp
[7]. Van Kampen, E.J. and Zijlstra, W.G. (1961). Clin. Chim Acta, 6, 538 - 544.
[8]. Ezeilo, G.C. and Green, J.H. (1978). An Introduction to Human Physiology (African ed.) Ibadan:
Oxford University Press.
[9]. Jendrassik, L. and Grof., P. (1938). Biochem. Z., 297, 81 - 89

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