These Popular Supershoes are on Ironman's Banned List for 2025 🚫 Models from Asics, New Balance, Hoka, and more have been listed as "prohibited" by Ironman for the 2025 season. Other shoes banned are the Asics Novablast 5, Puma MagMax NITRO and more... All of these shoes are thicker than the 40mm stack height • maximum allowed by World Athletics shoe regulations, which Ironman follows (as does World Triathlon)