In SI engineering mechanics, a force of 1 Newton acting through a distance of 1 metre gives 1 Joule of work.
In other words, 1N x 1m = 1J
The important point, is that there is a definite one-to-one correlation between the units: one is doing the same amount of work whether…
(a) one has 100 newtons acting through 5 metres, 100 x 5 = 500
(b) one has 5 newtons acting through 100 metres, 5 x 100 = 500
In both cases, one is doing 500 Joules of work.
In the realm of PE, we are talking about ppm theory, that is, trying to find relationship between time and weight. And we are talking about it in pounds per minute. It is a good start, but it is too naive to assume that there is a one to one relationship between minutes and pounds. If there were such a relationship, then one could get the same results by cutting the weight in half but doubling the time, or cutting the time in half but doubling the weight. This is probably not correct. Also, there is probably some minimum weight at which the stress is too small to stimulate any real growth. It’s complex, huh?
What we are trying to determine is the most effective weight to hang-time ratio that causes maximum growth_stimulus. Therefore, I’ll call the units “gs.” The trick is, we need to find the relationship between the two. And it probably isn’t linear as the ppm dialogue seems to presuppose.
Let’s for argument’s sake say that weight is way more effective than is time in stimulating growth. That is, within the realm of reason, a 10% increase in weight causes a larger growth stimulus than a 10% increase in hang time. In fact, to sharpen my point, lets say that weight is a squared function. If that were the case, the equation would be…
growth_stimulus = weight^2 x time
We need units for the equation, and I’ll say that the units are called “g’s” (gees)
Ok… given that weight in this example is a squared function, then if you double the weight for a given time frame, you _quadruple_ the growth stimulus, the g’s.
5 pounds for 60 minutes 5^2 x 60 = 1500 g’s
10 pounds for 60 minutes 10^2 x 60 = 6000 g’s <— 4x the stimulus!
On the other hand, if you double the time but keep the weight the same…
5 pounds for 60 minutes 5^2 x 60 = 1500 g’s
5 pounds for 120 minutes 5^2 x 120 = 3000 g’s <— only 2x the stimulus
Key point:
If one knew this relationship to be true, one would strive to hang at maxium safe weight for shorter time periods, rather than hang at minimal weights for maximum time. Until we know what the relationship is between pounds per minute, then we’re kind of shooting blind. We’d need a test group to move ahead and quantify the relationship.
Ddog