Working out might once have been a solo sport but couples are increasingly choosing to feel the burn together, even opting for matching work-out gear.
Healthy, body-conscious pairings are a frequent sight at the gym, with Saturday mornings recovering from the night before more likely to be spent thrashing up a hill than watching box-sets on the sofa.
Famous fitness fans including the Beckhams, Gordon and Tana Ramsay and Chloe Madeley and boyfriend James Haskell are perfect examples. Gisele Bundchen and Tom Brady too are frequently seen showing off their athletic physiques, while simultaneously honing them.
Leading the way elsewhere on social media is Instagram work-out star Austin Raye, 26, and his girlfriend Julian Daigre, 21.
Get it? The shirts?
The couple, both former cheerleaders from New Orleans, have gathered legions of followers thanks to their complex fitness routines that often combine acrobatics and muscle endurance.
Two weeks ago, a video of their workouts was shared on the Muscle Madness Facebook page and it has since been viewed more than 36 million times.
Says Daigre: "We take a look around us and try to make what we have to work with as interesting, challenging, and beneficial as possible. It makes things more fun."
And they're not the only ones who think so. Vicky Hadley, 23, and beau Josh Bryant, 26, a physiotherapist, are big believers in the mantra: couples who train together, stay together.
Bikini model and writer Vicky says working out a deux can actually be a sexy experience.
She told MailOnline: "Believe it or not I actually feel my sexiest when I'm sweating.
"The rush of endorphins and the fun, flirty atmosphere whilst we're pushing each other to get the extra reps in is pure motivation - plus I definitely enjoy seeing his muscles pumped!"
New couple Deni Kirkova, 26, and Toby Shaw, 24, say their working out together has already become a large part of their relationship.
Journalist and personal trainer Deni says: "I actually prefer training with someone as we can motivate each other...and Toby looks pretty hot when he lifts weights."
Is the red-faced and sweaty look not just a tiny bit off-putting? Not at all, thinks Deni: "Getting sweaty and reasonably red-faced is attractive and natural and we should embrace it - how on earth are we supposed to feel good about working out hard in the gym otherwise?"
"And besides: we sweat doing other things together too!"
London couple Georgie Simmons, 28, and husband Darren, 32, who run Instagram account VeganFamilyTV, have two children and have been together for six years.
They've been training as a couple for five and say they now use the gym as their way of making sure they have "adult time".
Says Georgie: "I love to train with Darren as he pushes me harder than I would do on my own, especially on the leg press! He knows when I have more to give and really believes in me."