So, what's the verdict, then? If you look at the overall result of the meta-analysis, it turns out that subcutaneous GH injections are not powerful muscle-builders, nor performance enhancers. Compared to a handful of other drugs from the arsenal of the world of doping GH is thus of relatively little value to the average cheater.
The meta-analysis at hand does yet also show that it does exactly what it's used for by those who think of it rather as a lifestyle drug: it yields significant improvement in body composition that may, however, be hidden under the significant increase in extracellular water.
Moreover, the overall effect size is everything but mindboggling (let's be honest, you can easily shed <2kg of body fat while gaining <1kg of actual lean mass by diet and exercise in no time). Accordingly, it would seem that the benefits of the administration of moderate amounts of GH (BBs have reported using ~20 units of HGH (that's >80µg/kg), almost always in conjunction with 50–75 µg/day of IGF-I to turn the mediocre into real gains | Brennan 2011), in fit, lean young men are almost as exaggerated as those of their initially alluded to, simply non-effective natural counterparts. For older individuals who have been shown to gain impressive 6% of lean mass while losing -15% of their total fat mass within 6 months on only 30µg/d (Rudman 1991), however, things may look differently, though.