For 2012 Mizuno’s racing flat gets a complete makeover and are now made on a curved last rather than semi-curved. We found this has made them a little narrower. The Musha 4 now features a new upper with the front overlay ending just behind the toes to allow greater flexibility in the forefoot so there are no irritation spots. Flexibilty is also helped by flex grooves in the sole. Beefier overlays connecting the lace eyelets to the toebox help to keep the foot securely in place. The mesh upper does a good job of keeping your feet cool and allow the shoes to dry quickly if they get wet, but there aren’t any drainage holes in the sole.
As in previous incarnations the soles feature Mizuno’s unique plastic wave in the midsole that acts a shock absorber and also helps move the foot from heel to toe. Above the wave now sits Mizuno’s AP+ foam rubber that Mizuno say improves cushioning, energy return and durability over previous incarnations. On the road the Musha 4 feel responsive with a little extra bounce, especially for heel and midfoot strikers. For a racing flat they’re pretty forgiving both in terms of cushioning and ride. With 9mm of drop between the forefoot and heel these are not exactly level like many more minimalist shoes, but offer comfort, especially when forms falls off and heel striking occurs later in a race. The new set up does weigh more than Musha 3 but at 227g (UK 7.5) they’re by no means heavy.
For a race shoe they offer more support and stability than most making them a versatile shoe to suit most needs over shorter distances. Efficient runners will have no problems going longer in them. For us they felt more like a cushioned racer or lightweight trainer than a full-on race flat, which for many will provide a forgiving race and fast training shoe.