Brooks Glycerin Flex - Men'sIntroducing the freedom of Glycerin Flex, a cushioned ride that doesnt boss your foot around. Made to move with you so you can run on your terms. The Brooks Glycerin Flex is a flexible, comfort focused daily trainer for runners who want a soft ride that emphasizes natural movements. Unleash you feet Feel the best parts of the run with our new innovative flex groove and podular flexibility, working together to provide flexibility and support where you