Kate Bosworth Teases Toned Abs In The Gym: 'Never Felt Better'

Actress Kate Bosworth is flaunting her toned abs while promoting her longtime trainer's fitness regimen.

The "Blue Crush" star shared a snap of her showing off her toned abs in the gym along with a sports bra and sports. The actress says that she has "never felt better" than she does now!

The 40-year-old actress took to Instagram to plug her longtime fitness trainer, Steph Watson, who she has trained with for the past several years.

"At 40, I have never felt better," she wrote in the caption. "I am super proud of my strength in our recent @roxy campaign, feeling more optimal now than I did 20 years ago running around in a bikini for 'Blue Crush.'"

"A lot of you have asked about my fitness routine, nutrition, and what it's been like working with my coach, Steph Watson, so I wanted to highlight her and share how it works," she explained, breaking down her thoughts into several steps.

"Steph creates a super simple plan for me that is custom to my body, my goals, and helps me establish sustainable, long-term habits," she began. "She helps me navigate all my traveling in the summer with easy food choices and a wholesome healthy nutritional plan."

She noted that Steph has her masters in nutrition and advocates for long-term health and gut optimization before going on to say, "Regardless of how busy I get with my chaotic schedule, she provides fun, short (but tough!) workouts to tone // sculpt in order for me to look and feel my best - no matter where I am in the world."

Kate has certainly been travelling a lot in the past year. She traveled to Bulgaria to visit her now-husband, "Accepted" actor Justin Long, on the set of "The Bulgarian." The two also took a trip to the Galapagos Islands early this month to celebrate the actor's 45th birthday.

Kate went on to say that she has trained with Steph for over five years, writing, "She has focused my mind // body connection through her highly efficient and specified training, which I will (unquestionably!) use life long. I could go on and on about her knowledge + brilliance in the health / wellness space... AND she happens to be one of my favorite people on the planet. So it will not shock you to learn that she gets my emphatic endorsement."

Steph Watson was one of the first people to comment on her post, writing, "Kate I couldn't be more grateful for your support and endorsement of my work. I love working with someone so dedicated to their health and fitness. Will never forget our first bonding conversation on the importance of drinking high quality water 5 years ago! WOW time flies. You've stayed consistent and dedicated to your health since the day I met you and it's so admirable and inspiring. Thank you so much for sharing."

Roxy, who Kate has collaborated with many times in the past, called her "The most beautiful human inside and

out." Other fans also praised how good Kate looked at 40 and shared nostalgic memories of the first time they watched "Blue Crush."

One fan loved to see Kate giving fans a behind the scenes look at how she achieves her fit physique. "Now THAT is cool. Not everyone gives shout outs like this to their team. It makes a huge difference in a person's career. Nicely done @katebosworth," one fan commented, to which Kate replied, "She's the best!!!" alongside a flex emoji.

Another follower called Steph's health and wellness plan the "best program ever" while a third fan said that they were "forever grateful" in a lengthy endorsement.

"Kate, if it wasn't for you, I'm not sure would have had the opportunity to train with @stephwatsonhealth as I have, I wouldn't be working alongside her, and I would not have realized that sustainable transformation is not bred from restriction," they wrote. "Forever grateful."