The progressive resistance system states In order to continually see progress (muscle development) the intensity of the workout must increase as your body adapts to the workout. The progressive resistance system is the only system I use and the reason in obvious. All other system evolves around the principles of progressive resistance. I dont subscribe to other workout systems because they may cause injury and I have had enough in my time. Most champion bodybuilders follow the progressive resistance system in one form or another. They may employ other principles, like superset, tri-sets, giant sets, drops sets, railroad (this old school) flush sets pre-exhaust sets, and post-exhaust sets and numerous others but the system remains the progressive resistance system. Simple a system is the application of principles, for instance. If I wish to continue to see results I must increase the intensity of my workout as my body adapts to the previous load. (Progressive Resistance System)

There are five ways to increase the intensity of a workout;
1. Increase the weight being used for a given exercise,
2. Increase the amount of repetitions used in a given set.
3. Decrease the amount of time resting between sets.
4. Increase the amount of sets used during a given workout.(volume training)
5. And of course any combination of the above three. For those with less than a year of training increase intensity by increasing weight only.

So if you are applying one of the five principles with the goal of increasing the intensity to match your bodys adaptation to pervious stress of exercise, then you are using the progressive resistance system.

The repetitions ranges determine the weight not the weight determine the reps. what I mean by this is that the goal is a rep range, when doing the progressive resistance system, not the weight used. For instance, if you can only do 1-4 reps on your first set then you are a power lifter not a bodybuilder. If you can only do 5-8 reps during your first set then you are doing heavy weight. If you can only do 9-12 reps during your first set then you are lifting moderate weight. And if you can only do 15- 25 reps then you are lifting light weight. Of course you understand that if you can only do these number on your first set then the numbers get less and less on all the sets that follow. For successful leg training you need more reps than the rest of the body. Heavy weight would be 8 to 12 reps, moderate would be 15-25 reps and light would be 24 to 40 reps (yes I said 40!)

This is part one of a two part article on the progressive resistance system