Changes in serum haptoglobin as an acute response to a marathon road race

In order to assess the possible occurrence of acute haemolysis with prolonged exertion, serum haptoglobin levels were determined from venous blood samples collected from eight male runners immediately preceding (PreRH), immediately following (PRH1), and 6 h following (PRH2) completion of a marathon road race. The subjects' mean age, percentage of body fat, and maximum oxygen uptake (VO2max) were 46 +/- 9 years, 12.1 +/- 3.4% and 54.9 +/- 8.4 ml kg-1 min-1, respectively. The mean race finish time for the subjects was 3:35 +/- 0:18 h:min. The PreRH, PRH1 and PRH2 averaged 129 +/-18, 97 +/- 48 and 86 +/- 35 mg dl-1 respectively. Significant differences of -32.5 mg dl-1 between PreRH versus PRH1 and -42.5 mg dl-1 between PreRH versus PRH2 were found. The difference between PRH1 and PRH2 of -10.6 mg dl-1 was not significant. No significant correlations were found between the decreases in serum haptoglobin and VO2max or race finish time. The data suggests to occurrence of an acute haemolysis with performance of the marathon road race.     

Recovery of pulmonary diffusing capacity after maximal exercise.

Pulmonary diffusing capacity (DICO), together with spirometric variables, arterial oxygen tension (paO2) and cardiac output were determined before and at intervals after maximal arm cranking, treadmill running and ergometer rowing. Independent of the type of exercise, D1CO increased immediately post-exercise from a median 13.6 (range 7.3-16.3) to 15.1 (9.3-19.6) mmol min-1 kPa-1 (P < 0.01). However, it decreased to 11.6 (6.9-15.5) mmol min-1 kPa-1 (P < 0.01) after 24 h with cardiac output and paO2 at resting values, and D1CO normalized after 20 h. Thoracic electrical impedance at 2.5 and 100 kHz increased slightly post-exercise, indicating a decrease in thoracic fluid balance, and there were no echocardiographic signs of left ventricular failure at the time of the decrease in D1CO. Also, active muscle (limb) circumference and volume, and an increase in haematocrit from 43.8 (38.0-47.0) to 47.1 (42.7-49.8) (P < 0.01), had normalized at the time of the decrease in D1CO. Vital capacity, forced vital capacity, forced expiratory volume in 1 s, peak and peak mid-expiratory flows did not change. However, total lung capacity increased from 6.8 (5.0-7.6) to 7.0 (5.1-7.8) litres (P < 0.05) immediately after exercise and remained elevated at 6.9 (5.1-8.7) litres (P < 0.05) when a decrease in D1CO was noted. The results demonstrate that independent of the type of maximal exercise, an approximate 15% reduction in D1CO takes place 2-3 h post-exercise, which normalizes during the following day of recovery.