Mean Poundage Index

It didn't give much useful information other than that the total poundage lifted per workout could be calculated and compared to that of the previous one.
In the search for a way of quantifying progress in strength training there have been several mathematical derivations. The first to my knowledge, was the "Total Tonnage System." In this system all that is compared is the total tonnage of a set or exercise in a program. This calculation was useful but limited. It didn't give much useful information other than that the total poundage lifted per workout could be calculated and compared to that of the previous one.

But what does that really say? Total poundage of a workout can be increased by simply adding one more set of only one rep. If this is continued total tonnage numbers will definitely increase but no progress will have been made in reality, despite what the numbers may be telling you. In addition, such training could very quickly lead to overtraining.

Power Factor Training

The newest of such quantification methods is the Power Factor calculation developed by Peter Sisco and John Little. This calculation takes its roots in physics in that it is a slightly modified version of the calculation for mechanical power. These are two problems with this system though:

    1) The Power Factor doesn't take distance into account. This is fine as long as the range of motion is kept constant. However Sisco and Little then developed a system of partial rep training based on the Power Factor calculation. This allowed for the use of very high poundage's, very short reps, and reduced time per set resulting in very high PF numbers. The problem is that the high PF from power factor calculations does not necessarily mean that muscle tension is higher in such sets.

    2) The time dependence of the power factor calculation actually encourages quick, sloppy reps since anything that decreases the time required for a set and exercise to be completed results in higher PF's. This time decrease, resulting in higher PF doesn't necessarily mean that progress is eminent. Indeed it could cause injury, a definite progress stifler.

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With these two calculations in mind I decided that there had to be a better way of quantifying weight training results. After careful consideration I noticed the major difference between the two systems which makes the PF slightly more useful. The top portion of the of the PF calculation is the total tonnage number! Dividing the total tonnage number by some variable seems to be a necessity if we hope to establish a useful comparison tool.

Sisco and Little used time as that variable. Though some form of time constraint and control is definitely needed, the better choice seems to be the number of sets. Since the number of is time dependant and using it as the deviser allows us to account for volume effects of training it seems that this should be the most logical choice. The resulting calculation looks like this:

Mean Poundage (MP) = (weight 1 x rep count) + (weight 2 x rep count)... for the total number of sets performed.

What this calculation really gives us is an average poundage moved per set of an exercise. This allows us to calculate the mean power output of varying set/rep schemes of various exercises and entire workouts.

The applications for this calculation are endless. In can be used to compare productivity of an entire days training plan to the next days for the same body part(s) training as long as the exercises are the same.

It is very interesting to compare workouts in this manner. One example is in comparing the progress made on a double progression scheme. Very often the double progression method employs a type of intensity cycling as shown by the following calculation. So for those who think the don't need to cycle intensity, you likely already are!

Bench Press Example Workouts:

Workout 1: 205 x 5, 205 x 6 MP = 1230
Workout 2: 210 x 5, 210 x 5 MP = 1050
Workout 3: 210 x 6, 210 x 6 MP = 1260

Notice how the number decrease in the second workout despite the use of a heavier weight and only one fewer reps. But when the reps gets back up to par in the third workout we show progress. This it actually took two weeks for true progress to become apparent.

This can actually be an advantage since it employs a type of heavy-light or more accurately high-low intensity cycling.

On the other hand a person could choose to use a smaller poundage increment which would allow him to get the full rep count at each workout.

Workout 1: 205 x 6, 205 x 6 MP = 1230
Workout 2: 207 x 6, 207 x 6 MP = 1242

The end result is the same when training is considered in two week blocks. The most important point is that you use what allows progress for the longest period of successive increases. For most trainees the seems to work best to go with smaller poundage increases but there are those who thrive on the double progression formula.

One thing should be noted about the use of this calculation. It is only useful if all other variables are kept relatively constant. These include: rep speed, and rest times. They don't need to be tracked down to the last millisecond but you should be watching the clock to make sure your workout time remains roughly the same at each session. Experiment with it a little and find what time frame suits you best, i.e. gives you the highest numbers and best progress.

Now with all of that in mind go out and Get Huge!

Keep life HEAVY!