Air, Gel, and Other Cushioning Tricks

Many running shoe manufacturers use proprietary cushioning devices. These include various configurations of air bladders, gel or liquid pads, as well as wedges, layers and compressed capsules of foam (typically EVA or polyurethane).

Every cushioning system has its fans, but all are designed to do the same thing: reduce the shock that's transferred to your body on impact. While the air, gel and liquid systems may retain their cushioning ability longer than foam, virtually all of them are contained within foam, so the extended life of these shoes is arguable.

Your best bet is to find a shoe that fits you well and suits how you run (overpronate, neutral, etc.). If it feels good when you run in it, don't worry about the air, gel, or other add-ins. If you need more cushioning than your shoe offers, most of them accommodate after-market insoles. Simply remove the shoe's original insole, and replace it with one of these cushioned gel or foam inserts.