In this exercise, do three sets of lifts with ten repetitions in each. The weight can be the same in each, but the rest interval between sets should be only 30-60 seconds. Start light -- maybe just 20% of your body weight at first -- until you find the right weight for you for these exercises. The right weight is one that challenges you over ten repetitions, but that you can ultimately complete.
The hamstring curls, like the leg extension, will increase your cadence as these workouts build the muscles in your legs that allow you to twirl the pedals more quickly.