ADAM LEVINE has been bending over backward for SHAKIRA – literally!

The Maroon 5 frontman has struck up a hot and sweaty friendship with his sexy “Voice” co-star over their shared love of yoga – but Shakira’s athletic sweetheart is crying foul.

European soccer star Gerard Pique – who’s been dating the Colombian hip-shaker since 2011 – is well-aware of Adam’s reputation as a ladies’ man and made sure to plant a lip-lock on his sweetie for the cameras at a recent game in Spain.

“His message was unmistak­able to Adam or anyone else who might have designs on his woman: Hands off, she’s mine!” said a source.

Adam, 34, has reportedly been inviting Shakira over to his home for intense Bikram yoga sessions, a form that’s practiced in hot and humid temperatures.

“Adam taught Shakira some moves and vice-versa,” the source added. “It was a great, sweaty experience.”

Meanwhile, Shakira, 36, and Gerard, 26, welcomed their first child – a boy named Milan – on Jan. 22. And although Gerard has been fuming about his ladylove’s new friendship with Adam, the handsome rocker – who’s currently between girlfriends – insists the new dad has no reason to worry.

“Adam says he’s just been helping Shakira lose some of her stubborn baby weight,” noted the source.

Besides that, 5-foot-3 Shakira just isn’t Adam’s type.

“Adam thinks she’s gorgeous, but he’s into tall supermodels,” the source explained. “Yes. Adam and Shakira have gotten hot and heavy, but it’s not about sex – it’s about yoga.”