For fitness fans, Hyrox is peak romance sweat, sore muscles and all

Lindsay Balkenbush needed a male partner for a pricey Hyrox mixed-doubles race in Las Vegas.A newcomer to Boise, Idaho, the paralegal and fitness instructor didn’t exactly have a Rolodex of potential race partners waiting in the wings.

So Balkenbush, 25, reached out to a local CrossFit gym, where owner Brian Wilkerson did her one better and volunteered himself.After training for and completing the race together, they went their separate ways — only for their athletic partnership to blossom into a romantic one a few weeks later.“It was a good way to get to know Lindsay,” Wilkerson, 26, told The Post.

“There’s a little bit of bonding when you go through some shared suffering.”They’re not the only people discovering that Hyrox can double as a relationship litmus test.Across the fast-growing fitness competition, couples are using the grueling global races to strengthen their bonds, while singles are turning to the sport to find someone who can keep up, literally and otherwise.Hyrox combines eight 1-kilometer runs with functional exercises including sled pushes, burpee broad jumps, farmer carries, lunges and wall balls.

Think marathon training meets CrossFit, with enough suffering packed into one event to expose whether a teammate is a cheerleader, a critic or a quitter.Balkenbush met Wilkerson at a particularly convenient time.His gym, CrossFit Casual, hadn’t opened yet, so “we had the whole gym to be able to train together and run together,” she recalled.

“We were training together probably two to three times a week.”There was, however, a complication.“We were very serious about doing this race together, so we didn’t want to jeopardize that,” Wilkerson said.“But at the same time, there were just some growing feelings.”Hyrox offered plenty of opportunities to find out whether those feelings would endure.

Those who opt for mixed doubles — a woman and man duo — have to divvy up demanding exercises, communicate when one person i...