Katharine McPhee shows off toned abs in Pilates session

Katharine McPhee showed off her toned tummy as she highlighted her workout routine on Instagram this week.

The 40-year-old singer — who is married to 74-year-old David Foster — used the app’s Stories feature to upload video of her grueling Pilates regimen.

She was clad in a black Alo sports bra with white trim and coordinating skintight leggings.

The songstress skipped shoes as she used fitness equipment in a pair of white and black Alo Yoga socks.

McPhee wrote across a mirror selfie, ‘Thank you @marymillermethod @alo. Socks are my fav.’

Katharine McPhee showed off her toned tummy as she highlighted her workout routine on Instagram this week

The 40-year-old singer used the app’s Stories feature to upload video of her grueling Pilates regimen

Katharine wore her bob haircut loose for her gym session, letting the blonde highlighted locks graze her shoulders.

She was also clad in jewelry, including a gold chain necklace and small, coordinating earrings.

The mother-of-one, who shares three-year-old son Rennie with Foster, also accented her look with a stack of gold bracelets.

The star went without makeup as she worked up a sweat during the challenging class.

The snippets showed her squatting, lunging, and stretching as she used her core muscles to keep balance.

Last fall the entertainer admitted that she and her husband sometimes don’t see eye-to-eye when it comes to raising their son. 

‘I want to start disciplining [Rennie] and Kat’s not really down with that,’ her music producer spouse told People in November. 

McPhee clarified: ‘No, that’s not true. I just want to discipline in my own way. It’s just a different approach. I think his era of parenting is different than mine.’

She was clad in a black Alo sports bra with white trim and coordinating skintight leggings

The songstress skipped shoes as she used fitness equipment in a pair of white and black Alo Yoga socks

McPhee made sure to tag the wellness brand as well as trainer Mary Miller

Katharine and husband David share three-year-old son Rennie, who was born in February 2021 and joined Foster’s five adult children

She explained: ‘There’s the more old-fashioned way of disciplining which involves time-outs and things like that.

‘My take is that you can have more mindful parenting opposed to just assuming that a two or three-year-old can have time alone to reflect on what they’ve done poorly.’

The singer-songwriter added, ‘I think the more new way of parenting is understanding that with a child, there’s only so much that they can intellectually understand.’

The couple met in 2006, when Foster served as a guest mentor on American Idol. 

They struck up a romance in 2017, and tied the knot in June 2019.