Changes in urinary pH following bicarbonate loading.

The purpose of this study was to determine the effect of bicarbonate doping on urinary pH following intense exercise. Sixty-five university students (14 female, 51 male) were tested in a double-blind fashion on two separate occasions one week apart. In random order each subject received a 500 mL bottle containing water, flavour crystals, plus either placebo (P) or sodium bicarbonate (B) in a dosage of 0.3 gm/kg body weight. One hour later following an 800 m run a urine specimen was obtained and analyzed in duplicate on a Corning pH meter. Urinary pH was significantly increased in the B condition (P = 6.17 +/- 0.6; B = 7.61 +/- 0.4; p less than 0.01). There was no difference between the response of the males (B = 7.59 +/- 0.3; P = 6.14 +/- 0.6) and females (B = 7.67 +/- 0.4; p = 6.29 +/- 0.6). The times for the 800 m run were B = 2.35 +/- 22 s; P = 2.36 +/- 15 s; p greater than 0.05. These data indicate that urinary pH may be a suitable parameter for detection of bicarbonate doping.