Glycerin 21 vs Aero Glide 4

The Brooks Glycerin 21 is a max-cushion daily training shoe built for one job: making your everyday miles feel soft, calm and comfortable. This is the plush end of the Brooks range, a neutral running shoe that leans into cushioning rather than speed. At 280g it is not light, and it will not snap you through a fast finish, but that was never the point. What you get is a deep, forgiving underfoot feel that holds up well over long easy runs and recovery days, and a 10mm drop that suits heel and midfoot strikers alike. We rate it as a dependable cruiser for runners who want protection and a smooth, quiet ride over anything sharp or racy. If the £165 price gives you pause, the cheaper Brooks Ghost 16 covers similar daily duty with a touch less plush. But if soft comfort is what you are after, the Glycerin delivers it honestly.

The Salomon Aero Glide 4 is the brand's big-cushion road running shoe, built for soaking up easy miles and long runs without asking your legs for anything back. With a tall 43.2mm heel stack and no carbon plate, this is a comfort-first daily training shoe rather than a racer. What sets it apart from most max-cushion rivals is the tall 11.7mm drop, which rolls you forward off a generous heel and suits runners who land heel-first. It is not the lightest shoe in the class at 250g, and it is not trying to be snappy. What you get instead is a soft, planted, protective ride that stays comfortable when the miles pile up. If you loved the Aero Glide 3, this is a familiar, refined take on the same idea. We rate it as a dependable cushioned trainer for steady runners who value comfort over pace.