View all slides | Contents of this slide

Lecture Notes

The next two types of dynamic resistance exercise are isokinetic resistance training and plyometric resistance training. In isokinetic resistance training, you have a fixed speed of movement throughout the range of motion, and the resistance will vary with the force extended. So, for example, if you're doing a leg extension where you're kicking your leg out, if you push harder on that movement you're going to feel more resistance, and this is very different from the previous example where we were talking about the amount of resistance, or the weight—the barbell or the dumbbell—being fixed. In this case the speed of movement is fixed, and as you push harder through your range of motion you'll feel more resistance. So the final category here are plyometric exercises, and this is defined as a rapid, dynamic, eccentric contraction and stretching, followed by a rapid, dynamic, concentric contraction. So examples of plyometric-type exercises might be jumping onto, doing box jumps, another exercise might be lateral jumps over a stepper or a raised platform, so jumping side to side, and it really is taking advantage of that stretch reflex of your muscle, and then that you follow that with a dynamic contraction of the muscle.