For those seeking the latest innovation in racing footwear and a shoe that can help maximize both your height and your running efficiency, Puma has dropped a game-changer. The Fast-RB Nitro Elite, known as the Rule Breaker, lives up to its name with a unique design that pushes the boundaries. With a midsole stack height of 58 mm—18 mm above World Athletics’ guidelines—it is technically non-compliant for official races, making it truly a rule breaker. Puma has crafted this shoe to maximize speed and efficiency on race day, regardless of regulations. Here’s an in-depth look at what makes this shoe so unique and how it performs.
Specs
Category: Neutral racing (plated)
Drop: 12 mm
Stack Height: 58 mm (heel)/46 mm (forefoot)
Weight: 355 g (12.5 oz.)
Availability: Limited (only 1,000 pairs worldwide)
Price: CAD $549
Upper
Each facet of the Fast-RB Nitro Elite makes the shoe what it is, but the power mesh laceless upper is one thing that stands out. You might be asking yourself, how does this sock keep me secure? The laceless design is reinforced with Puma’s PWRTAPE in key areas for added structure and support. The shoe slips on like a sock, providing a snug fit that feels locked in on every stride. My only concern is that it does run slightly narrow, making it ideal for those with narrow feet and tight for those with a broader foot. While the laceless design may feel novel to some, it works in sync with the shoe’s streamlined build, keeping your foot secure without the need for traditional lacing adjustments.
Midsole
The midsole is an engineering marvel, practically jaw-dropping at first glance. Puma’s proprietary Nitro Elite foam delivers ultra-soft and highly responsive cushioning, while the three embedded plates provide unparalleled propulsion. A snappy full-length carbon plate runs through the entire shoe, enhancing energy return, while two additional TPU plates in the forefoot maximize power during toe-off. During testing, the bounce with each step was remarkable—this is possibly the most responsive shoe I’ve ever worn. The high stack height and dense foam offer exceptional shock absorption, giving a buoyant, almost “anti-gravity boots” feel.
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While the added height and plump midsole design enhances shock absorption, I found it negatively affected the stability of the shoe on tight turns and uneven terrain. There were a few tripping scares, but managed to stay on my feet. At 355 grams, The Fast RB is one of the heavier racing shoes on the market. It would be best suited for longer distances like half-marathons or marathons, where sustained speed and energy efficiency outweigh the need for lightness.
Outsole
The PUMAGRIP outsole is designed to handle a variety of surfaces. While it performs beautifully on flat, paved roads, its grip can feel compromised on uneven terrain or during quick, sharp turns. Additionally, the outsole’s design includes a midsole cutout that may trap small stones, making it less suitable for gravel or rocky paths. This shoe is strictly intended for use on paved surfaces, where it truly shines in performance.
Verdict
The Puma Fast-RB Nitro Elite is a striking, one-of-a-kind shoe that pushes the boundaries in every way imaginable. With its towering stack height, triple-plate configuration and league-of-its-own responsiveness, it’s a premium choice for serious racers looking to challenge personal records. Although its weight and design make it less ideal for non-road terrain, it excels over long distances, where its speed and energy return stand out as unmatched in the market.
It’ll also turn heads on the start line, with a limited-edition design and a status as one of the few “illegal” racers, available to fewer than 1,000 runners worldwide.
