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Steroids Promote Endurance

Steroids should only be taken under close supervision of a doctor. The information provided here should not be taken as medical advice.

Many athletes are led to believe by coaches, training partners, websites and ill-informed literature that cardiovascular performance can be enhanced by ASS. Although less common a reason for athletes that are abusing AAS especially in the modern-era, the theory still exists amongst many that ASS can improve endurance. They believe this is down to possible increases in haemoglobin levels after an increase in testosterone concentration. This is due to AASs stimulating the production of erythrocytes and having a direct effect on the erythropoeitic stem cells in the bone marrow (Mooradian et.,al1987).

A study by Alén (1985) found that blood haematocrit had increased 9.6% (P<0.05) in the study group (n = 5), but not in the control group (n = 6) follwing 26 weeks of ASS administration in 5 power athletes. In addition there was an increase in red blood cell count (RBC) (P<0.05) and unchanged mean corpuscular haemoglobin (MCV). Blood haemoglobin concentration did not change markedly and consequently mean corpuscular haemoglobin (MCVC) concentration level in the study group decreased significantly (P<0.01). Also the erythrocyte sedimentation rate decreased (P<0.05) in the study group alone. The mean values of serum alanine aminotransferase, alkaline phosphatase and gamma-glutamyltransferase remained within normal range in both the study and control groups. It is worth noting that the subjects were strength athletes and not endurance athletes. A similar investigation where endurance athletes are used as subjects may be beneficial for further understanding the results of AAS on endurance.
However the theory that ASS improves endurance performance still has little support due to growing body of evidence finding no physiological adaptations for endurance athletes.

An investigation by Win May and Mya Tu (1975) on physical fitness and anabolic steroids found a significant increase in the anthropometric measurements and in the static and dynamic strength areas as compared to the placebo group but found no significant difference in balance, coordination, flexibility and cardio respiratory endurance compared to the placebo group. These results appear in line with the majority of the literature. Johnson et.,al (1975) for example also concluded that steroid treatment does not appear to have any effect on the development of endurance. From this evidence there seems to be no justification for athletes to take steroids to improve endurance.

Few studies have been done recently on the effects of AAS on endurance. This is partly down to the decrease in athletes using AAS for endurance purposes and the obvious ethical constraints. The use of erythropoietin (EPO) has become popular rendering any expected benefits of AAS void. Also in modern day sport, AAS are primarily perceived to be a muscle growth drug used for more explosive athletic events. Furthermore, evidence shows there may be detrimental consequences of ASS on the cardiovascular system which is discussed later in this section.

End of steroids and endurance in fitness and exercise