Lenny Kravitz, 62, attributes his enduring fitness to a straightforward, old-school method: checking if he can still fit into his 28-inch waist pants. The Grammy winner shared in a "Men's Health" cover interview that this simple test has become his primary gauge for maintaining his health and physique.

"I can gauge everything by how I’m in my pants," Kravitz told the magazine. "Like, if my pants are a little tight, I know I’m getting outta’ shape. My friend Denzel Washington gave me this phrase, ‘The pants don’t lie, the pants don’t lie.’"

Kravitz also incorporates his performance attire into his training. Known for wearing leather and denim on stage, he often trains in the same garments. "It also means I can fit in a workout anytime, anywhere," he explained.

While Kravitz is known for his sculpted physique, he noted a desire to improve his leg strength. His trainer has consequently increased his lunges and deadlifts, drawing inspiration from Arnold Schwarzenegger's approach to calf development. Additionally, Kravitz focuses on minimal rest between exercises and performs hundreds of abdominal repetitions in each workout, contributing to his signature 10-pack abs.

Responding to speculation about his physique, Kravitz affirmed that his results are entirely natural. "All this is natural: no peptides, no human growth hormone, no testosterone," he stated. "There’s nothing wrong if people want to do those things. But there’s an alternative. You can do it naturally with exercise and food. Is it harder? Yes. Does it take more work? Yes. But that’s how I choose to do it, and it’s 100 percent attainable."

Kravitz began training seriously in the mid-1990s, a shift influenced by observing Mick Jagger's disciplined approach to training and nutrition. "Most people I knew in the rock and roll world were not taking care of themselves in that way but Mick Jagger was a big influence on me," Kravitz said. "We were on holiday together once in the Bahamas and I watched how disciplined he was about his training and nutrition and realized that this was a major part of his formula."

More than three decades later, Kravitz continues to prioritize consistent exercise, disciplined nutrition, and his reliable waist-size reality check.