Fig. 7. Velocity and strain by individual. Total shortening velocity is the total strain distance divided by the time between strain onset and peak strain. Fast shortening velocity is the total strain between onset of fast shortening and peak strain divided by the time between the onset of fast shortening and peak strain. Strain and shortening velocity are expressed as negatives to facilitate viewing. Mean total shortening velocity (including slow shortening) was –1.3 FL s^–1. Mean fast shortening velocity across individuals was –2.5 FL s^–1, suggesting that the sternohyoideus functions to produce mechanical power. The majority of strain occurred in the fast portion of the strain cycle in all individuals. l, minimum FL, l₀, resting FL.