By weight. Go to a (running store), here in Colorado Springs we have Boulder Running Co; Colorado Running Co; Runners Roost, Find a good running store in your area. Talk to someone who is not a minimum wage salesperson, but a runner. What kind of shoe is up to you Asics, New Balance, Nike, whatever. I run in New Balance Baddeley 890's it's a good lightweight running shoe. Get what you like and the style you like in a lightweight shoe.
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How do you all define a "light" shoe? Can you give an example so I interpret it correctly and then can check them out? Thanks.