MuscleScience

B.E.N.


Technically it isnt that the muscles of the legs that elicit more hormone release (HGH, T, C) it is the actual amount of muscle that is stimulated that facilitates the release of more anabolic hormones. It just so happens that a large percentage of muscle mass is in the legs. By working the legs logically one will stimulate more muscle mass, thus more anabolic hormones. There is a number that a lab worked out that said that x amount of muscle mass stimulated will case X amount of hormone release. I can not think of the number off hand of what that is. I am not totally sure that it is a widely accepted number as i have not seen it in as a test in many of the protocols for athletic performance. But I do know that studies exist showing large amounts of anabolic hormones in serum after vigorous leg workouts.

Lemonada8,


If there is already a shoulder issue I do not see AAS usage as helping to repair it or prevent further injury. Now could it increase the injury because of increase contractile strength of the muscle. I would say that its a logic conclusion. After all the force from the muscle has to be transfered through a lot of structure before it impulses the ball.

BIG,

Flexing in the mirror is a form of working the muscle. When you flex for example the biceps, the triceps have to contract as well to keep the arm from moving. I could not say how much it would effect recovery but I really see it as no difference than doing another set of bi's the next day after an arm workout.

tadpoleboyy,


Great question, my undergrad was in biology and is a great degree to have.

There are three basic muscle types in the body. Smooth Muscle, Cardiac Muscle and Skeletal Muscle. In this conversation we are going to talk about Skeletal Muscle just for everyone's clarification that may be reading this.

Within Skeletal Muscle (SM) there are different subtypes of fibers. For the purpose of this discussion we will talk about the three most accepted subtypes. Slow Twitch, Fast Twitch type IIA and Type IIB. I must point out that some researchers have possibly identified addition subtypes which I will only briefly mention as not to confuse everyone because it is not completely agreed upon by all authors the last time I checked.

Type I (slow twitch):

Type I slow twitch muscle fibers (ST) are fibers that express high levels of aerobic enzymes relative to other types and are very dense in mitochondria. The muscles themselves have a very high capillary density to bring in additional blood supplies. ST fibers are resistant to fatiguing and can contract and stay contracted repeatedly without fatiguing to a point. The main energy pathway of ST fibers is that of aerobic means, due to the increased expression of aerobic enzymes. These fibers can produce energy under anaerobic conditions but do not have the capacity to do so verses other types of muscle fibers. These muscle fiber types are generally used in everyday activities and are for long duration lower intensity exercises such as walking or jogging.

Fast Twitch Fibers Two Types:

Type IIb Fast Glycolytic (FG):

FG fibers are a type of fast twitch fiber that produces energy almost exclusively via anaerobic means. (without oxygen) They fatigue very rapidly and produce a very fast and forceful contraction relative to that of ST fibers. They are very low in mitochondrial density and have low capillary density along with decreased expression of aerobic enzymes relative to that of ST fibers. These fibers are mainly involved in very short and forceful contractions such as jumping or throwing a baseball. These fibers can best be trained by plyometric exercises as well as relatively heavy weight lifting.

Type II A Fast Twitch Oxidative Glycolytic (FOG):

FOG muscle fibers are a kind of hybrid fiber type between FG fibers and ST fibers. They display characteristics of both fiber types in that they can use both aerobic and anaerobic means to produce energy. FOG fibers can contract fast and forcefully just like FG fibers do but they also have built in fatigue resistant properties that ST fibers have. This is achieved by having more mitochondria and aerobic enzymes along with a higher capillary density in the muscle compared to FG fibers. These fibers are postulated to have the ability with training to morph into either ST or FG fibers. Meaning that with specific training such as in long distance running, that a FOG fiber can adapt and mimic to an extent the properties of ST fibers. These fibers will start to act more like a ST fiber than that of a normal Fast Twitch type of fiber and vice verse.

Additional Fiber Types:

In 2003 a paper authored by Spangenburg and Booth, proposed that there was an additional fast twitch fiber type called Type IIx. This is described as a fiber type between that of Type IIa and type IIb. Just to confuse everyone Type IIx use to be a alternate nomenclature for Type IIb fibers. The reason I bring it up at all is that depending on the text book and author this fiber type may or may not appear or be taught. Although Spangenburg and Booth are not the only ones to describe this potential new fiber type, their paper is the most commonly cited one in the literature. Just in case anyone is doing research at home or has learned it different in exercise physiology class.

References:

Essentials of Strength Training & Conditioning by Thomas R. Baechle, S Roger W. Earle,. Second Edition
Human Kinetics (2000)

Molecular regulation of individual skeletal muscle fibre types
E. E. Spangenburg and F. W. Booth (2003)
Acta Physiologica Scandinavica
Volume 178 Issue 4, Pages 413 - 424