Biochemical and haematological changes in Sydney's the Sun City-to-Surf fun runners

Before this study was undertaken, biochemical and haematological changes in collapsed fun runners have been interpreted only by comparison with changes observed in trained marathon runners, or by comparison with normal subjects. This study was undertaken to establish the pattern of biochemical and haematological changes to be expected in non-collapsed fun runners as a result of competition, and to use this pattern as the basis for comparison with changes observed in collapsed fun runners after similar competition. Forty-three fun runners (28 males, 15 females) who competed in the 1978 City-to-Surf run volunteered as non-collapsed "controls", while 10 runners (nine males, one female) who collapsed during the 1978 City-to-Surf run became "casualties" for comparison. Blood for detailed analysis was collected from the controls two weeks before the 1978 City-to-Surf run, immediately after the run and one month later; blood from the casualties was collected immediately after the run, and one month later. As a result of competition, three patterns of changes were observed, namely, haemoconcentration; tissue damage and altered organ system function; and alteration in carbohydrate metabolism. More intense tissue damage probably accounts for disproportionate changes of some variables in male controls compared with female controls, and in casualties compared with controls. Casualties differed most from controls in degree fo depression of serum bicarbonate levels, and degree of elevation of blood urea nitrogen, serum creatinine, uric acid and bilirubin levels. A wide scatter of blood sugar levels immediately after run both in controls and in casualties reflects the stress of prolonged exertion.