i gave a presentation last semester about bicarbonate supplementation prior to exercise bouts. it's interesting because the only 3 supplements recognized as giving a performance boost are caffeine, creatine, and bicarbonate. yet nobody talks about bicarbonate, i'm assuming because you can buy a pound of sodium bicarbonate for about $3, so nobody advertises. anyways it was interesting reading the results from a lot of studies showing significant differences in performance in short distance and middle distance (half mile) running bouts. the differences in blood pH was only about 0.1 (7.5 as opposed to normal blood pH of 7.4). sodium bicarbonate has a pH of like 10.3 so this is way more alkalinizing than any food you would eat, and still you can how well the body buffers this load.
this past weekend i was in switzerland at a meeting for the congress on nutritional concerns in renal disease. there was an interesting panel on hyponatremia and exercise performance. after the panel ended i thought about how a sodium bicarbonate load prior to exercise could potentially benefit an anaerobic bout via the bicarbonate and an endurance bout via the sodium (you'd probably have to vary the ingestion times though as to actually achieve an alkinizing effect or retain the sodium without pissing it out).