| Spec | Adizero Boston 12 | Endorphin Speed 4 |
|---|---|---|
| Best price now | £77.00 | £89.99 |
| 90-day low | £67.91 | £73.50 |
| 30-day average | £97.11 | £114.91 |
| RRP | £160.00 | £180.00 |
| Category | Tempo | Tempo |
| Surface | Road | Road |
| Weight | 267g | 233g |
| Drop | 7mm | 8mm |
| Heel stack | 37mm | 36mm |
| Forefoot stack | 30mm | 28mm |
| Carbon plated | No | Yes |
| Stability | No | No |
| Review rating | 4.0 (1) | — |
The Adizero Boston 12 is adidas at its most versatile: a £160 tempo running shoe built to be the one trainer that handles almost everything bar your easy days. It is the rod-equipped middle child of the Adizero family, sitting below the Adios Pro racers but with enough snap to make threshold sessions and long runs feel purposeful. At 267g with a 7mm drop it is not feather-light, and the ride leans firm and direct rather than soft and forgiving. That is the point. Push the pace and the Boston rewards you with a propulsive, slightly aggressive roll through toe-off. Jog it slowly and it can feel stiff and a touch dead underfoot. In our view this is a do-it-all daily trainer for committed runners who like a firmer, faster shoe, and a genuinely capable marathon training partner. The newer Adizero Boston 13 softens and lightens the formula if this version reads too stiff for you.
The Saucony Endorphin Speed 4 is the do-everything plated trainer, and one of the most complete running shoes in its class. At 233g with an 8mm drop it sits in the sweet spot between a cushioned daily trainer and a stripped-back race shoe, so one pair covers your tempo days, your long runs and the odd parkrun. The plate gives you a gentle nudge through toe-off without the aggressive, all-or-nothing feel of a full carbon racer, which is exactly why so many runners keep coming back to it. We rate it as the shoe to reach for when you want speed without committing to a dedicated marathon shoe. It is not the cheapest tempo option at RRP, and the plusher Endorphin Speed 5 has since taken over the line, but the Speed 4 remains a brilliant buy when it drops in price. If you want the plate but not the price, this is the one to watch.
A side-by-side comparison makes the trade-offs between two running shoes easy to see, but the right pick still depends on how you run. Weight and stack height shape the feel underfoot: a lighter shoe with a lower stack feels nimble and fast, while a heavier, taller stack gives a softer, more protective ride for long miles. Heel-to-toe drop changes where you feel the load, with lower drops asking more of the calves and Achilles.
The price figures update from the UK retailers we track daily. The best price now is the cheapest tracked price we can currently link to, the 90-day low shows how cheap the shoe has been recently, and the 30-day average tells you whether a price is a genuine drop or just the going rate. Coverage is partial rather than complete, so always confirm the final price and your size on the retailer site, and set a price alert on the model you want so we can email you the moment it drops.
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