How J. Lo's Trainer Changed My Body

David Kirsch and Kahlana
Photo: Courtesy

When David Kirsch wants me to do something—say, text him a picture of what I’m eating—he always finds a clever approach. “I’ll send you a picture of my lunch if you send me a picture of yours,” he messages me at noon one day, while I’m literally splitting open a bag of Sour Patch Kids. The guilt kicks in as the picture of his grilled chicken and arugula salad pops up on my phone, and I have no choice but to throw the candy in the trash.

I met David Kirsch in 2009 when I played guinea pig for an InStyle story about how a woman can slim her figure in six weeks. I was assigned to the fitness guru who has trained everyone from J. Lo to Julia Roberts and is famously credited for Heidi Klum’s return to the runway eight weeks after delivering her second child. We became instant friends, and he assured me that after six weeks of his 60-minute, five-days-a-week workouts my body would be in the best shape it’s ever been. He wasn’t lying. In the end, I lost 18 pounds and had endurance strong enough to rival that of Serena Williams. Kirsch’s approach, in a nutshell, is about clean eating and cardio sculpting—lightweights and high reps. Although the six-week program was quite possibly the most challenging experience I’ve ever gone through, it was also the most gratifying.

Fast-forward to six years later. I called David this summer, two months before my wedding, to whip my body into shape for my big day. Thankfully, we weren’t starting from scratch, and I had gained only a few pounds since our last stint. We trained five days a week, and each day was different—some consisted of strength training, others were more focused on cardio. He put me on a daily regimen of his protein shakes for breakfast and grilled fish or chicken with veggies for both lunch and dinner. The result? At each of my three dress fittings, my gown had to be taken in because I was losing so much body fat. By my wedding day, I had dropped 4 inches from my waistline, and my dress fit like a glove.

I can’t help but reflect on what it is exactly that makes David’s plan work so well. After giving this some serious thought, I realize the answer is simple: It’s just David. He’s been in the business for 25 years and knows what works—and what doesn’t. Unlike some other trainers, he never loses his cool and somehow makes each and every one of his clients feel at ease. He understands your strengths and weaknesses and finds a way to inspire you to push yourself as far as you can go. He never body shames or lets you body shame yourself. His motto? You can’t take back what’s already done. Move forward.

David Kirsch Book Cover - Embed

Shortly after our initial run in 2009, Kirsch became a single father to twin daughters Emilia and Francesa. He suddenly had less time and had to find a way to balance caring for two newborns and managing a hefty schedule, all while developing a more speedy approach to living a healthy lifestyle. With the launch of his new book, David Kirsch’s Ultimate Family Wellness ($17.35;, he is using his experience to help people live a healthier, more balanced life. If your days are crazed like mine and you find it nearly impossible to make time for the gym, this book will be your health bible. It offers five-minute workouts, quick and easy dinner recipes—plus his formula to losing 5 pounds in five days. Amen!

Related Articles