broscience

Broscience is advice or information, especially about fitness and nutrition, that circulates among gym-goers and online communities but lacks scientific backing.

It typically comes from fellow lifters or influencers who speak with confidence about what works, based on personal experience or hearsay rather than controlled studies.

He swore that eating six meals a day boosted metabolism, but that's just broscience.

The term combines "bro" (the stereotypical gym buddy) with "science" to suggest pseudo-expertise.