A banned peptide hormone that promotes muscle growth, fat loss, and recovery, difficult to detect but subject to strict monitoring.
Human Growth Hormone (HGH), also known as somatotropin, is a peptide hormone that stimulates growth, cell reproduction, and regeneration. In cycling, it's used for its recovery and body composition benefits.
• Stimulates liver production of IGF-1 (Insulin-like Growth Factor) • Promotes protein synthesis and muscle growth • Enhances lipolysis (fat breakdown) • Improves collagen synthesis for connective tissue • Accelerates recovery from training and injury • Increases bone density
• Faster recovery between hard efforts • Improved body composition (less fat, more lean mass) • Enhanced tendon and ligament repair • Better adaptation to training stress • Maintained muscle mass during weight loss
• Indirect performance gains through recovery • Not a direct endurance enhancer like EPO • Primarily used during training blocks • Helps maintain performance during stage races
• During intense training periods for recovery • To accelerate injury healing • Combined with other substances in doping programs • During off-season to build strength • Throughout stage races for day-to-day recovery
• Often combined with testosterone • Used alongside insulin for anabolic effects • Part of comprehensive polypharmacy regimens • EPO for endurance, HGH for recovery
• Very short half-life (20-30 minutes) • Naturally occurring hormone (synthetic is identical) • Clears system within hours • Requires blood testing (not urine)
• Distinguishes synthetic from natural HGH • Detects different molecular forms • Detection window: 24-48 hours only • Requires precise timing to catch users
• Measures IGF-1 and P-III-NP levels • Indirect evidence of HGH use • Longer detection window (weeks) • Less legally robust than direct detection
Pre-2004: • No reliable test available • Widely believed to be undetectable • Extensive use in professional sports • Athletes felt safe using HGH
2004-Present: • First blood tests introduced • Very few positive tests despite suspected use • Detection window remains major limitation • Biological Passport helps identify indirect markers
• Unannounced blood tests • Targeted testing of suspicious athletes • Testing during early morning hours (when HGH levels naturally peak) • Out-of-competition testing crucial
• IGF-1 levels monitored over time • Abnormal elevations trigger investigation • Combined with other hormonal markers • Longitudinal tracking improves detection
• Very few confirmed HGH positives in cycling • Detection window makes testing difficult • Most evidence comes from investigations, not tests
• Tyler Hamilton admitted to HGH use • Lance Armstrong confessed to HGH protocols • Detailed in USADA Reasoned Decision (2012) • Part of sophisticated doping programs
• Acromegaly (abnormal bone growth) • Joint pain and swelling • Carpal tunnel syndrome • Increased cancer risk • Insulin resistance and diabetes risk • Heart enlargement
• Permanent facial bone changes • Organ enlargement • Metabolic dysfunction
HGH represents the detection challenge in modern anti-doping. While tests exist, the short detection window and need for blood samples make it difficult to catch users. This drives investment in biomarker-based detection methods.
The main myth is that HGH is a powerful performance enhancer like EPO. In reality, its benefits are primarily in recovery and body composition, not direct endurance gains. Another misconception is that HGH is undetectable - while challenging, modern biomarker testing and the Biological Passport make it increasingly risky.