Are any of you guys interested in the mathematical approach of quantifying the effectiveness of your workouts? I am trying to look for a system in which I can readily quantify how well a workout went when using different rep schemes and different weight and am having difficulty finding one.

Whenever I up the weight for a lift I find that the number of reps that I can complete decrease and I feel as though I am not completing enough work to guarantee progression.

Is there a formula out there that I can use that applies to varying the weight used in an exercise and the number of reps over time I need to complete to maintain progression?