The brains behind the world’s first-ever sperm race are spilling the tea to TMZ — disclosing their donors are on one wild ride getting prepared for the big race day.

Eric Zhu and his Sperm Racing startup crew broke it down on “TMZ Live” Wednesday, telling us sperm is a key biomarker for male health, so they’ve turned 2 young donors — one from UCLA and the other from USC — into full-blown sperm-athletes, giving them thousands of dollars per week to help them fine-tune their swimmers for race day glory.

The tech teen dream team’s swimming in strategy — giving us every juicy detail of the donors’ prep, from tailor-made vitamins to pineapple-juice chugging. This isn’t a half-baked stunt — it’s a well-seeded plan.

The team didn’t shy away … they came through with the goods on that one — and you gotta catch the clip, ’cause they also let us know whether there’d be an egg waiting at the finish line for the winning swimmer to inseminate.

The guys also admitted to us they’ve had some casinos and adult-themed sponsors knocking on their door … but they’re staying focused ’cause the real goal is all about shattering the taboo and raising awareness about male fertility, which has significantly dipped over the years.

They’re so serious about it, in fact, that during our entire interview, a scientist from their team was hard at work with test tubes in the background — so clearly, the younger gen is all in, doing it for the men of the future, one seed at a time.

But you gotta brace yourself, ’cause for now, this race is where the real action will go down!