In the early 90's I read a book on fitness by Fredrick Hatfield (Dr. Squat) that changed the course of my life. It was a very complicated book for me. It was heavy on anatomical terms and physiological concepts. It was way over my head.
I hadn't started college yet. At that point in my life I was convinced I would work in the Northern Utah steel industry or as an interstate trucker. I had been working on my CB phrases and voices since the first time I saw "Convoy" sometime in the middle 70's. Seemed like a practical use for that kind of talent.
My best friend, Justin and I had been working out together for years (since early high school days) and we were absolutely convinced that a good life could not be attained without growing FRICKIN ENORMOUS muscles. In fact, we were totally sold on the fact that no woman would ever love us if we didn't have 20+ inch "Arnold" arms. To achieve this, we ate copious quantities of meat, drank gallons of milk, lifted WAY too much weight, and snapped up "Muscle and Fitness" magazines as fast as they hit the stands to learn what to do next. The latter is a fact I am quite ashamed of.
We also used to read a lot of books. Which brings me to my point. Fredrick Hatfield's book "Hardcore Bodybuilding a Scientific Approach" taught me my first physiology lesson. In it I learned that your body had 2 different energy systems. These 2 energy systems (aerobic & anaerobic) had 3 different ways of generating (fueling) movement. These, I found out were:
1. Powerful and explosive movements fueled by the ATP PCr system (anaerobic) - which only lasts a few short seconds like when doing 2-6 reps of a heavy movement.
2. Strong and steady movements fueled by the Glycolytic system (anaerobic) - which last 90-120 seconds like when you do 12-20 reps of a moderately heavy weight , and finally
3. relatively light and constant movements fueled by the oxidative system (aerobic) which, if fueled properly, may continue indefinitely. This is the pathway trained distance runners and cyclists use.
Hatfield's theory was that if Bodybuilders wanted to maximize gains and create MONSTROUS muscles, they needed to work each system in a way that it was designed to perform. He designed workouts which used each metabolic pathway individually instead of lumping together as was the theory of the time. It was cutting edge back then. It still has merit today.
In order to attain "Optimal Health" as is the goal of GPP, you must use these 3 "metabolic pathways" in a way that maximizes the potential of each. It is something much of the exercising world still does not understand. It is what makes your workouts more complete and effective.
When doing Hatfield inspired workouts, take the time to learn about these specific energy pathways. Concentrate on how each set of movements affects you. Try to feel the difference in the fatigue factor of each type of movement. These are quite different.
If you pay close attention you will find that failing in the ATP-PCr pathway simply makes you unable to do a rep. Despite your best efforts you simply will not be able to complete another rep. It doesn' t hurt. You don't breath heavy; you just cant do another rep. (Be careful. If you are a rookie - under 2 months with us - you have no business maxing out ANY pathway. You may become extremely injured. NOT good).
ATP-PCr pathway failure starkly contrasts to failing the Glycolytic pathway. Failing in the Glycolytic pathway can be characterized by a "burning" feeling. This feeling will be mainly isolated to certain areas and it will escalate usually to the point of quitting the lift due to intense localized pain.
The Oxidative pathway is very different from the other two. If you are well trained and you do not exceed oxidative capacity, you will not fail while in the Oxidative pathway any time soon. Failing in the oxidative pathway is generally typified by complete systemic exhaustion and fatigue. Heavy breathing, weakness, and the inability to go on will be prevalent.
I love these "Hatfield" types of workouts. I have created many of them. You will get to know them better in the coming months and years. We do not perform the workouts the way Mr. Hatfield wrote them or probably intended them. Through the years I have found ways of customizing these workouts in ways which specifically match GPP purposes. However, I honor Mr. Hatfield for turning me onto this concept by having each one bare his name.