Eighteen female rowers were filmed performing sweep rowing on a Stanford Rowing Ergometer. The rowers were grouped according to ergometer scores (rpm) and the films were analyzed frame-by-frame for the drive phase of the stroke. Parameters characterizing rowing in general were determined as well as those separating the novice from the skilled. Prior to when the oar was perpendicular to the shell, the importance of the trunk was to transfer the power generated by the extension of the knee to the horizontal linear velocity of the oar. When the oar was perpendicular to the rowing shell, the skilled rowers were characterized by a higher horizontal linear oar velocity (2.58 +/- 0.21 m . s-1 vs 2.17 +/- 0.19 m . s-1). This appeared to be due principally to the more rapid extension action of the knee (4.18 +/- 0.48 rad . s-1 vs 3.01 +/- 0.96 rad . s-1). The sequence of first extending the knee then the trunk, combined with a higher sum of trunk and knee angular velocity when the oar was perpendicular to the shell (7.31 +/- 0.76 rad . s-1 vs 5.86 +/- 0.61 rad . s-1) also appears to be related to the higher horizontal linear oar velocity of the skilled rowers. The difference in time between when the maximum angular velocities of the knee and trunk occur is less for the skilled than the novice (0.150 +/- 0.061 s vs 0.235 +/- 0.049 s, respectively). Based on the ratio of actual to possible sum of knee and trunk angular velocity, the efficiency of the skilled was determined to be greater than that of the novice (87.2 +/- 6.9% vs 75.8 +/- 10.1%).