Read the whole thing... pretty good.
I found this part to be particularly interesting
In many situations, you don’t know what your maximum weight is, I mean you think that something is your maximum weight is and it isn’t, because the athlete can be wrong about his maximum achieving state. We can use pulse rate to discover the maximum weight. If the athlete has a pulse of less than 180, it means that he can do more.
I may have to try it out.