Steroids have permanent effects. Some changes persist long after the usage of testosterone is stopped. Medical research finds permanent changes in muscle fiber composition. Testosterone increases aggression in male rats even after stopped.

Testosterone:Some effects are temporary. Some are long-term or even permanent. The side effects are complex.

Muscle. Do anabolic steroids cause permanent gains in muscle size? Recent research has found that the muscles of powerlifters who have used anabolic steroids are different. This applies even to lifters who have stopped using the steroids.

The number of myonuclei/fiber and the proportion of central nuclei were significantly higher in the [powerlifters who used anabolic steroids] group.

Skeletal muscle morphology
The muscle fiber areas of the men who used anabolic steroids were larger. The group of powerlifters includes men who had ever used steroids: not just those currently using them. The group of men who were compared had never used steroids.

Similar results were seen in the trapezius muscle... in [the trapezius muscle] the proportion of fibers expressing developmental myosin isoforms was higher in the [powerlifters who used anabolic steroids] group compared to the [other] group.

Anabolic steroids—such as testosterone injections—affect certain muscle groups more than others. The trapezius muscle had more fibers in people who used anabolic steroids. But it also had fibers that were different.Traps

The initial effects from [anabolic steroids] appear to be maintained for several years.

Once an athlete takes these performance-enhancing supplements, the changes persist. The muscle fiber area changes. The composition of the muscles changes. And this lasts even after the steroids are discontinued.

Note:In effect the muscular gains from steroid use are permanent. In this context permanent means the same thing as long-term.

Trapezius. Muscles respond differently to exercise and anabolic steroids. The permanent muscle gains from anabolic steroids may be greater in muscles that respond the most. The neck and trapezius muscles have the most androgen receptors.

Myonuclear number in both muscles was higher in [power-lifters] compared to [untrained men] and in [powerlifters who used anabolic steroids] compared to both [power-lifters] and [untrained men]. In conclusion, [androgen receptor] content differs greatly between human neck and limb muscles.

The expression of androgen receptors
Neck and trapezius muscles respond the most to anabolic steroid use, including testosterone replacement therapy. Could steroid users be detected by the proportional sizes of the trapezius and neck muscles?
Behavior. How does testosterone therapy affect behavior in the long-term? Does it cause only temporary changes or long-term, even permanent changes? One study was done on rats. Some rats were given testosterone injections.
The rats given testosterone had more aggression when provoked. And after the rats returned to baseline and were no longer being given testosterone, they still had higher levels of aggression.

All three [rat groups given anabolic steroids] significantly increased tail pinch-induced aggression compared with corresponding nontail pinch tests, even at study endpoint. These results suggest that alterations in androgen-dependent behaviors by pubertal [anabolic steroid] exposure can persist long after drug exposure, and some effects may even be permanent.

Long-term effects of steroid exposure
It is possible that some changes occur in the brain when testosterone is used. The results of the study indicate that these changes could be long-term or even permanent, which is even longer-term.

So:People who have taken anabolic steroids—even for medical purposes—may have permanently increased levels of aggression.

Balance. Testosterone injections can affect the brain in other ways. The balancing mechanism can be affected. One report describes a man who used anabolic steroids. After usage of testosterone the man developed vertigo. This effect persisted.

The moment of appearance and long-lasting vertigo as well as the results of laboratory examinations indicate a poststeroid permanent disorder of the central part of the equilibrium organ. Such a diagnosis seems to be most probable here.

Poststeroid balance disorder case report
The effects of testosterone therapy are profound. Many side effects, even those that are not common, can occur. Even a person's balance can be affected. And many of these side effects are not short-term.

Thus:Some effects persist for months and years. Some are even permanent, lasting throughout a person's remaining life.

Adverse effects. In medical literature adverse effects means side effects. One report from Clinical Chemistry describes that scientific evidence finally supports testosterone and its muscle-building properties.

And:It notes that the adverse effects of testosterone are reversible—except in women and children.

New evidence supports the view that supraphysiological doses of anabolic steroids do have a definite, positive effect on muscle size and muscle strength.... Most of the adverse effects of AAS are reversible but some are permanent, particularly in women and children.

Endocrine aspects of anabolic steroids
Hormone changes. The use of testosterone replacement therapy affects a man's hormone status. One study has found that the suppression of a man's hormones does not go away immediately after stopping testosterone injections.

Instead:It takes up to one year to normalize. And cholesterol levels take six months to return to normal after testosterone is stopped.

Some individuals had a sustained suppression of LH and FSH for a period of 1 year... the cholesterol profile was normalized within 6 [months]. The long-term consequences of these findings remain to be established.

Long-term perturbation of endocrine parameters
Not permanent. These hormone changes are long-term but not permanent. The men's hormone levels of LH and FSH returns to normal. So too did their cholesterol levels. Their hormone profiles recovered.

Short-term:Some effects of testosterone replacement therapy are short-term. These side effects include acne and testicular atrophy.

AcneTesticles, Shrinkage
Summary. All people have some level of anabolic steroids in their bodies. They are part of life in both men and women. The usage of drugs that contain synthetic testosterone has further effects. When we take steroids, our bodies change.

Tip:It affects muscle composition permanently. It changes behavior permanently. It can cause long-term side effects.