PHA is a system designed by Dr Arthur Steinhaus in the 1940's and brought to prominence in the 1960's by Bob Gajda an American bodybuilder and Mr Universe. PHA was designed to keep blood circulating around the body throughout the workout and prevent pooling in a certain muscle group. Typically using a handful of exercises alternating upper and lower body, or, at least not re-focusing heavily on the last muscle group trained PHA training is a great addition to any program.
Using the theory of PHA in my training programs and carefully selecting the order of exercises the body can work at a higher rate for longer, burn more calories and truly receive a total body workout.
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