Cardiovascular Toxicities of Performance-Enhancing Substances in Sports.

[Darryl Shaw]

Cardiovascular Toxicities of Performance-Enhancing Substances in Sports.

Abstract.

Athletes commonly use drugs and dietary supplements to improve athletic performance or to assist with weight loss. Some of these substances are obtainable by prescription or by illegal means; others are marketed as supplements, vitamins, or minerals. Nutritional supplements are protected from Food and Drug Administration regulation by the 1994 US Dietary Supplement Health and Education Act, and manufacturers are not required to demonstrate proof of efficacy or safety. Furthermore, the Food and Drug Administration lacks a regulatory body to evaluate such products for purity. Existing scientific data, which consist of case reports and clinical observations, describe serious cardiovascular adverse effects from use of performance-enhancing substances, including sudden death. Although mounting evidence led to the recent ban of ephedra (ma huang), other performance-enhancing substances continue to be used frequently at all levels, from elementary school children to professional athletes. Thus, although the potential for cardiovascular injury is great, few appropriately designed studies have been conducted to assess the benefits and risks of using performance-enhancing substances. We performed an exhaustive OVID MEDLINE search to identify all existing scientific data, review articles, case reports, and clinical observations that address this subject. In this review, we examine the current evidence regarding cardiovascular risk for persons using anabolic-androgenic steroids including 2 synthetic substances, tetrahydrogestrinone and androstenedione (andro), stimulants such as ephedra, and nonsteroidal agents such as recombinant human erythropoietin, human growth hormone, creatine, and β-hydroxy-β-methylbutyrate.

http://www.mayoclinicproceedings.com.../1307.full.pdf

[Garrett Smith]

Re: creatine

Of all the nonsteroidal, nonstimulant ergogenic aids, creatine is the most widely used and marketed.78 Its prevalence ranges from sixth-grade students to professional athletes, and it is used without proper monitoring or proven efficacy.

Of all the supplements out there, creatine is the one with the most studies backing it, so much so that it seems to be regarded as a foregone conclusion that it is an ergogenic aid with relatively few and typically easily manageable "side effects" (drink more water to prevent dehydration with it).

That part simply makes me wonder what "proven" means to the Mayo Clinic...ie. does it have to be a prescription item under a doctor's care? They also talk about monitoring creatine use, and yet give no suggestions as to how that should be done, while saying that

Fortunately, the number of adverse effects are few and dose dependent, including weight gain, muscle cramps, and gastrointestinal distress.80

There are some very valid points in the article, however, in my opinion it is simply a supplement-bashing article, arguing that all supplements must be proven safe first (while drugs are okay even while proven dangerous).

[Darryl Shaw]

Originally Posted by Garrett Smith

That part simply makes me wonder what "proven" means to the Mayo Clinic...ie. does it have to be a prescription item under a doctor's care?

I presume they mean that it's efficacy is not proven because there are responders and non-responders and at present there is little evidence to suggest that creatine supplementation gives athletes a significant competitive advantage over athletes that obtain their creatine from dietary sources i.e. meat.