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Locomotion that is driven by muscle activity dominates the daily energetic expenditure in most animals. In fish, routine propulsion when swimming at low, steady speeds and at various gaits is powered primarily by red, oxidative muscle. In Bluegill Sunfish (Lepomis macrochirus), swimming speed is thought to reflect the most energetically efficient gait type. Since field observations of Bluegill suggest that intermittent swimming is the preferred gait, we hypothesized that intermittent locomotion would be more energetically efficient than steady swimming. To test this hypothesis, we used electromyography to analyze muscle activation intensity of Bluegill swimming steadily in a flume and volitionally intermittently in a pool. In the flume, muscle activation intensity and tailbeat frequency increased as a function of speed. However, when swimming volitionally in the pool, muscle activation intensity varied relative to average velocity and tailbeat frequency was lower than in the flume at the same velocities. Although we expected muscle activation intensity to be higher when steady swimming at a given speed, ~48% of fish (n=11) had higher muscle activation intensities when swimming volitionally when compared at the same speed in the flume. Also, there was a positive relationship between speed and glide duration, but there was no relationship between speed and muscle activation intensity when swimming intermittently. Instead, intermittent swimming may lower fatigue and enhance maneuverability, rather than increase energetic efficiency.