Researchers in Holland concluded that the manual sex act releases massive amounts of the drug dopamine, aiding restful sleep.
The study even likened ejaculation to a heroin rush.
Now a Brazillian team trying to discove how to help sufferers of Restless Leg Syndrome (RLS) – the acute version of the pre-sleep limb spasms occasionally felt by most people – have refined the data and applied it to real-life cases.
RLS is a neurological disorder that afflicts one in ten adults in the US and Europe.
In the monthly Sleep Science Luis Martin, leader of the research team at Sao Paulo's Federal University, pointed to the study results from the University of Groningen in The Netherlands, which shows ejaculation in men swamped their brains with dopamine.
He said: “Manual penile stimulation was performed by the volunteer's female partner producing a wide variety of rewarding behaviours.
“Parallels are drawn between ejaculation and heroin rush.
“This is a simple way for men to reproduce the effects of RLS treatment drugs, without the cost and side effects of using dopamine agonists.”