Buffers (metabolic)... Ion buffers in the body are significant in acid base equilibrium (slightly alkaline pH of 7.4 in the blood and 7.2 within the cells), by binding with the H+ ions that result from an increase in CO2 during exercise. They include cellular protein anions (A-), hemoglobin (Hb & HbO), and bi-carbonate (HCO3-).

When CO2 is dissolved in the blood stream, it becomes carbonic acid (H2CO3) which disassociates into H+ and HCO3- with the hydrogen being buffered by hemoglobin, while the bicarbonate enters the plasma.

When the blood pH is acidic, concentrations of Hb- and prot- drops as they bind with H+ and are illiminated accompanied by Na+ to maintain electrical neutrality. The concentration of bicarbonate increases because carbonic acid (H2CO3) formed by C02 is disassociated into HC03- as well as H+, but overall the relative concentration of hydrogen ions increases causing a drop in pH. The renal tubules replace Na+ with H+ and reabsorb Na+ and HCO3- conserving the cations, eliminating the acidic pH, and restoring the supply of buffers to normal.

If circulation and oxygenation of the organs (especially the kidneys in this case) is optimal as with Body'Fit pH Fitness exercises, the observed consequence is that the kidney's become more active in the buffering process speeding up recovery from exercise that triggers hyperventilation.