The research database for performance-enhancing drugs, peptides, hormones, and human optimization. Understand what was tested, what changed, and what the evidence cannot tell us.
For athletes, coaches and research-minded readers. Evidence, not protocols.
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FROM THE REEL TO THE RESEARCH
Saw the reel? Follow the mechanism.
Explore the Comparison Series and Mechanism Minute, from the molecular signal to the human evidence.
Three ways to read the evidence: a landmark experiment, a peptide trial and a safety finding. An editorial selection—not a benefit ranking.
Landmark human researchHuman · 1996Abstract summarized · Quality not appraised
Testosterone plus exercise increased fat-free mass by 6.1 kg; bench-press strength rose 22 kg and squat capacity 38 kg. Testosterone without exercise also outperformed placebo for measured muscle size and strength. Mood and behavior were unchanged.
Study context & limitations
Randomized trial comparing weekly testosterone enanthate or placebo, each with or without standardized resistance training.
Forty-three normal men received 600 mg testosterone enanthate or placebo weekly for 10 weeks; exercise groups lifted three times weekly.
This was a small, 10-week study in normal men using a supraphysiologic regimen. The abstract reports mood and behavior but no longer-term safety assessment or author-stated limitations.
Peptide trialHuman · 2023Abstract summarized · Quality not appraised
At 48 weeks, average weight loss was 24.2% in the highest-dose group versus 2.1% with placebo.
Study context & limitations
A randomized, blinded trial compared retatrutide with placebo for weight loss over 48 weeks.
338 adults with obesity, or overweight plus a weight-related condition, participated.
Digestive side effects were common and dose-related. Heart rate also increased with dose. These findings describe this trial's population and follow-up.
Safety findingsHuman · 2010Abstract summarized · Quality not appraised
The trial stopped early after more cardiovascular-related adverse events with testosterone: 23 men versus 5 with placebo. Testosterone improved leg-press and chest-press strength and loaded stair climbing.
Study context & limitations
Randomized trial comparing daily testosterone gel with placebo for 6 months, with adverse events and physical performance assessed.
The trial enrolled 209 community-dwelling men aged at least 65 with mobility limitations and low testosterone; mean age was 74, with substantial chronic disease.
The authors cautioned that the small trial and its medically complex, mobility-limited population prevent broad conclusions about testosterone safety.