Purposely slow velocity resistance exercise (i.e., 10 sec concentric and 10 sec eccentric), sometimes called slow tempo, is a popular training method, but limits the loads that can be lifted (e.g., <50% 1RM). This study compared the biomechanical properties of slow tempo (SLOW) and maximal velocity (MAX) resistance exercise. Healthy resistance-trained men (n=5) performed two testing sessions (barbell squat and bench press) in random-order; a SLOW session (1 set x 10 repetitions at 28% 1RM, 10 sec concentric and 10 sec eccentric), and a MAX session (3 x 10 at 70% 1RM, volitionally controlled eccentric and maximal concentric velocities). A force plate and linear position transducer were used to collect kinetic and kinematic data for every repetition of both protocols. Statistical significance was set at α=0.05. For both exercises, both concentric and eccentric mean force (N) and power (W) for each repetition were greater for MAX. When the entire training session (barbell squat and bench press) was examined, SLOW exhibited greater time under tension, while MAX produced greater work (J) and impulse (N•s). Contrary to suggestions in both the lay and scientific literature, SLOW resistance exercise produced less force, power, and work than MAX resistance exercise.