FIGURE 1.

The influence of exercise on the ${\text{NO}}_3^{-}-{\text{NO}}_2^{-}-\text{NO}$ pathway after the ingestion of dietary ${\text{NO}}_3^{-}$. Conditions within exercising skeletal muscle, namely, a relatively lower pH and greater extraction of oxygen from the peripheral blood, promote the reduction of ${\text{NO}}_2^{-}$ to NO.