Vegans have better sex, according to James Camerons' new film The Game Changers.
The film follows three college athletes who took part in an experiment.
After avoiding animal products, the athletes wore machines which measured their nighttime erections.
According to the results, the mens' erections were 'longer and fuller', making the men conclude those on a plant-based diet may enjoy a better sex life and leading one to say: "So really, the guy eating the big steak is soft?"
All three athletes then resolved to eschew animal products on 'date nights'.
Sex is not the only physical marker considered in The Game Changers, which recently debuted at Sundance to audience acclaim.
According to director Louie Psihoyos, previously best known for making The Cove: "We’re trying to dispel the myth that you need protein from animals to become a 'real man'."
The film features a number of vegans who exhibit high levels of strength and athleticism.
They include martial-arts fighter James Wilks - who dropped animal products after becoming injured.
He says: "Unable to train for six months after my injury, I started researching the optimal diet for recovery, and stumbled across a study about the Roman Gladiators, which concluded that they ate little or no meat.
"This seemed really far-fetched to me since I was confident that animal protein was necessary to build muscle, sustain energy levels, and recover from injury."
The results he achieved on a plant-based diet were 'so profound' he wanted to share them with a bigger audience.
So far, this audience has been enthusiastic about the film.
The atmosphere at the movie's Sundance Festival debut was described as 'electric' by filmgoers.
In addition, a review by the Berkshire International Film Festival said: "This film should be shown in every festival around the world to create real change!"
There is no official release date for The Game Changers yet.