Sildenafil [Viagra]: Increases Muscle Protein Synthesis

X-post. Originally posted by /u/SuperAgonist. Posted here with u/comicsansisunderused formatting and editing.

Full paper: Sildenafil Increases Muscle Protein Synthesis and Reduces Muscle Fatigue (2013)

Viagra works by increasing Nitric Oxide (NO)-like signalling, through PDE5 inhibition. The inhibition of PDE5 results in increased cGMP signalling, which then induces similar pathway activation like NO.

This one is a little more out there and among the least applicable, but it amused me that this could be a PED. This study referenced above included 11 subjects, all healthy males, out of which 6 received Viagra (25mg/day orally considered on the low end), whereas the other 5 males received placebo.

After 8 days of daily Viagra administration, without exercise of any kind, the muscles of all participants were tested for multiple parameters. The main and most important findings were that the Viagra users had double the rate of protein synthesis as the placebo group - an increase to those on par with those receiving TRT. This might be of interest to PEDs users who only use SARMs, as it seems to me that an increase in protein synthesis in conjunction with a SARM, at a time when testosterone is suppressed, is beneficial.

In addition, the Viagra group had reduced muscle fatigue - during a physical test in which fatiguing isokinetic contractions were performed, the Viagra group completed ~50% more muscle repetitions than the placebo group. Try not to read too much in to that conclusion though - the sample group had a mean age of 44 and 55 respectively with mean body fat % of 27% and 35%. Not exactly our typical PED user, significant improvements in strength in this group can be made with little effort.

The conclusion on this is that PDE5 inhibition leads to an increase in skeletal muscle. I don't expect any of us to start running viagra for this benefit alone, but the muscle synthesis is interesting. I've not read anything about reduced synthesis on a SARM only cycle as testosterone falls, but if that holds than perhaps it has a place after all.