Hailey Bieber‘s fitness intentions are clear.

The Rhode Skin founder shared a look into her workout routine nearly three months after giving birth to son Jack Blues Bieber with husband Justin Bieber. On Nov. 22, Hailey rang in her 28th birthday by hitting the gym with fitness trainer Kirsty Godson, who clients also include Olivia Rodrigo and Kaia Gerber.

In a video posted to Instagram Stories, Hailey—wearing a black, long-sleeved crop top and matching shorts—used a  resistance band and ankle weights while performing leg lifts on a yoga mat. For that particular exercise, she also engaged her core by resting one hand on a balance ball.

Meanwhile, a second photo showed the model giving a thumbs up.

She wrote in the caption, “bday burn.”

Hailey and Justin, 30, welcomed their baby boy on Aug. 22. Since then, the two—who were very private about Hailey’s pregnancy, only announcing the news when she was already six months in—have largely kept a low profile as they continue to nest with their son.