The effect of eccentric contraction velocity on quadriceps oxygen dynamics

The purpose of this study was to investigate the effect of eccentric contraction velocity on quadriceps oxygen dynamics. Fifteen healthy male volunteers were tested eccentrically at 60 and 180 ◦ /s for a duration of 30 s. A probe for near infrared spectroscopy was placed on the rectus femoris allowing determination of muscle oxygenation (MO) levels and blood volume (BV). Higher MO and BV levels were observed at higher compared to the lower velocity. These results suggest that during eccentric knee extension at slow muscle contraction velocity, mechanical compression directed toward blood vessels is augmented resulting in blood flow disturbances and further evolving into hypoxic state within muscle tissues.