Fig. 4.

Relative reduction (%) in peak (A) and total (B) vasodilator responses to single forearm contractions at 10, 20, and 40% MVC during l-NMMA administration compared with saline (control) condition in young and older adults. NO synthase inhibition (l-NMMA) reduced peak vasodilator responses to a greater extent in young compared with older adults at 20 and 40% MVC. NO synthase inhibition reduced total vasodilator responses to a greater extent in young compared with older adults at all contraction intensities. *P < 0.05 vs. young.