Jessica Biel is setting the record straight about what it takes to maintain a certain level of fitness.The 43-year-old Hollywood actress admitted that her toned body viewers saw in "The Better Sister" requires a strict, rigid fitness and nutrition plan not a realistic long-term regimen."Everyone is talking about the white dress," Biel explained in a TikTok video of her viral ensemble that showcased her back muscles. "And how do we stay strong as we get older."JESSICA BIEL SHARES RARE GLIMPSE INTO MONTANA FAMILY LIFE WITH JUSTIN TIMBERLAKE AFTER LEAVING HOLLYWOOD"Specifically, as women, how do we keep our back strong?" she added."I wanted to share that, that peak shape in that show is not maintainable unless you are living the strictest most rigid lifestyle with your nutrition and with your fitness, which I cannot do," Biel continued. "So Im currently back on my plan to sort of get a little bit back toward that shape."The "7th Heaven" alum went on to explain that her routine focused heavily on muscle-building and flexibilitytwo key elements she insisted are paramount to her wellness plan.JESSICA ALBA EMBRACES SELF-CARE AND SUMMER VIBES IN BIKINI PHOTOSBiel was seen in a workout room with gym equipment, as she told her fans that her workout consisted of "dumbbell hip thrust, 10 x 4 sets, each dumbbell is 10 kg." She noted that she would normally use a barbell instead of dumbbells.In the second workout video clip, Biel was seen doing an exercise called "romanian deadlift," then "hamstring curls" with a yoga ball.The "Candy" actress continued to show her different workout routines throughout the social media video.She concluded her video by stretching on the floor in a split, "Youve got to build muscle Thats a key part of my particular routine. And a ton of flexibility.""Lets get older and stronger together," Biel ended her video with a smile.Her fans flooded the comments section thanking the actress for her honesty.CLICK HERE TO SIGN UP FOR THE ENTERTAINMENT NEWSLETTER"Thanks for admitting that's not sustainable," one comment read.Another fan wrote, "thank you for speaking about the lifestyle that comes with maintaining! this kind of transparency is so important.""Love how honest and real you are," another comment read.Biel wrote in her TikTok caption, "I'm no expert but I want people to be healthy, safe, and strong. Remember to warm up and cool down"The Hollywood star tied the knot with pop singer Justin Timberlake in 2012. They share two sons, Silas, 10, and Phineas, 4.