Parasympathetic Nervous System 
Branch of the autonomic nervous system that slows the heart rate. 

Partial Reps 
Performing an exercise without going through a complete range of motion either at the beginning or end of a rep. 

Peak Contraction 
Exercising a muscle until it cramps by using shortened movements.

Pec's (pectorals) 
Abbreviation for pectoral muscles of the chest. 

Performance benefit 
Improvements in physical fitness as a result of exercise. 

Peripheral Vascular Disease 
Lack of oxygen supply to the working muscles and tissues of the body, resulting from decreased blood supply. 

P.H.A. – Peripheral Heart Action 
A system of training where you go from one exercise to another, with little or no rest, preferably alternating upper body and lower body exercises. Designed for cardiovascular training and to develop muscle mass. 

Plyometric exercise 
Where muscles are loaded suddenly and stretched, then quickly contracted to produce a movement. Athletes who must jump do these, i.e. jumping off bench to ground, quickly rebounding to another bench. 

PNF Proprioceptive Neuromuscular Facilitation 
Stretching exercises used to increase an individuals flexibility. 

Pose Down 
Bodybuilders performing their poses at the same time in a competition, trying to out pose one another. 

Power 
Strength + speed. 

Power Lifts 
Three movements used in power lifting competition; the squat, bench press and dead lift. 

Power Training 
System of weight training using low repetitions, heavy weights. 

Progressive Resistance 
Method of training where weight is increased as muscles gain strength and endurance. The backbone of all weight training. 

Pumped 
Slang meaning the muscles have been made large by increasing blood supply to them through exercise. 

Pumping Iron 
Phrase that has been in use since the 1950's, but recently greatly popularized. Lifting weights.