Is Insulin useful for Sport?

Insulin is a vital hormone for blood glucose regulation, but its use in sport is highly risky and banned by the World Anti-Doping Agency (WADA) in most competitive events. Some bodybuilders use exogenous insulin combined with anabolic steroids and growth hormones to enhance muscle protein synthesis and glycogen storage. This practice is extremely dangerous: overdose can cause severe hypoglycemia leading to unconsciousness, coma, or death. Insulin also promotes fat storage and may impair long-term insulin sensitivity. For healthy athletes without diabetes, there is no proven performance benefit that outweighs these risks. Evidence comes from anecdotal reports and animal studies, not controlled human trials. Athletes should instead focus on natural strategies to improve insulin sensitivity: low-carb training, intermittent fasting, adequate sleep, and a nutrient-dense diet. A MyBody-X DNA test can reveal genetic variants (e.g., in IRS1, PPARG) that influence insulin action, but does not provide a basis for insulin therapy. Conclusion: Insulin is not a sports supplement; it is a prescription drug with serious health hazards.