Bodybuilding Pharmacology: Roid Muscle Architecture
By: Jerry Brainium
Anabolic steroids increase muscle size and strength through various mechanisms, including an increase in muscle protein synthesis and a significant decrease in muscle catabolic processes. Psychological effects also play a role. The increased aggression often noted with steroid use fosters more intense, heavier training. One aspect of steroids not previously examined is how they affect the internal structure of muscles; that is, the way muscle fibers contract.
A group of researchers who had previously studied the effects of combining testosterone enanthate injections with weight training for 12 weeks recently published a new study.1 In the earlier study subjects received an injection of testosterone enanthate that was 3.5 milligrams per kilogram (2.2 pounds) of bodyweight. That amounts to 315 milligrams of testosterone weekly, a conservative amount for a typical bodybuilder. Another group got a placebo injection. As expected, the steroid group made considerably greater gains in muscle size and strength.
The new study, which also took place over 12 weeks, involved 10 of the same subjects who used the same amount of testosterone enanthate injections and engaged in weight training; another group got a placebo. The researchers focused on structural changes in the triceps muscles in the two groups, which were both training hard. Strength gains were measured by increases in one-rep-maximum poundages on the bench press.
Those taking the testosterone injections made significantly greater strength gains than those in the drug-free group. The steroid group also showed increased muscle pennation, which refers to the direction in which individual muscle fibers run between the origin and insertion points of a muscle. Muscle pennation determines the direction of muscular contraction, and the increased pennation in the steroid group increased muscle force through more efficient contractions. Those in the drug-free group did not experience that muscle pennation change, though changes they did show led to a finding of no significant difference in muscle thickness between the two groups, which would surprise many people.
The major discovery of the study was that even conservative doses of anabolic steroids appear to promote changes in a muscle's internal architecture, which results in greater muscle contractile force'and thus greater muscular strength'when combined with training.