A New Signature Trainer
San Francisco 49ers running back Christian McCaffrey has introduced his first signature training shoe, The CMC, with performance brand While on Earth. The announcement came in an August 24 Instagram post, where McCaffrey said he spent thousands of hours designing, testing, and refining the shoe over the past year.
McCaffrey described the shoe as built for "stability, control and explosive movement," qualities that mirror the training philosophy showcased in the accompanying video. The video emphasizes preparation becoming instinct, with narration about repetition, physical preparation, and mental discipline, including lines like "Before the snap, there is no thought" and "You don't rise to the occasion. You fall to the level of your training."
"I've been training my entire life, and for the last year I've had the opportunity to turn that experience into something of my own," McCaffrey wrote. "The result is the CMC, my first signature shoe with @whileonearth."
Design and Features
While on Earth said The CMC was designed as a versatile trainer for explosive and dynamic workouts, prioritizing stability and support without sacrificing flexibility. The shoe is positioned alongside the brand's lightweight Move Trainer and Rhythm Runner models.
Todd Meleney, co-founder and CEO of While on Earth, described the shoe as offering "the ultimate locked-in fit" for athletes. "We created the ultimate locked-in fit to carry you from heavy strength work to your quickest, most explosive movements without sacrificing comfort," he said. "It provides stability, versatility and comfort across a wide range of movements."
McCaffrey's personal involvement shaped the design. Forbes reports that he had input throughout roughly a year of development. He said the design journey began "in my head based on the experience I've had with footwear during my entire athletic career." He focused on a heel counter to keep him locked in and a midsole prioritizing stability and comfort, aiming to address two qualities he found missing from his previous footwear: stability and explosiveness.
The shoe's construction includes a single-layer lightweight nylon upper, a rubberized toe cap for protection, and a midfoot plate to minimize twisting. McCaffrey said having his own signature trainer is a "proud moment" because he believes it's the best on the market: "We built this product from the ground up and we've nailed it."
Background and Football Context
The shoe's launch comes as McCaffrey enters his 10th NFL season, having led the league in yards from scrimmage in two separate seasons. He joined While on Earth as a co-founder and investor in summer 2025, according to Forbes, while Heavy. reports he joined in August 2025.
McCaffrey recently returned to 49ers practice after the team deliberately reduced his workload during training camp. He participated in team drills on August 23 after sitting out since August 8, logging four touches. McCaffrey said the time away was planned: "This was part of the plan from the jump."
The 49ers are preparing to open the regular season against the Los Angeles Rams in Melbourne, Australia, on September 10. They have one preseason game remaining, on August 27 against the Las Vegas Raiders.
Both Forbes and Heavy. highlighted McCaffrey's personal connection to the shoe, with Forbes quoting Meleney praising McCaffrey's meticulous approach and Heavy. emphasizing the shoe's relation to his training philosophy as he appears to package that philosophy into a product bearing his initials.