I'm about to let you in on the best kept workout secret in Dallas. I live in East Dallas and for several years I've noticed a boxing gym on Columbia Avenue. Tons of teenage boys and girls jumping rope, throwing punches outside. A few months ago I finally walked in and asked if they gave adult lessons. Carlos Castillo, the coach there, said yes, but for a donation. Aguila Azteca is a non-profit that gets kids involved in Golden Gloves competition, teaches inner-city low-income kids about sportsmanship, keeping their grades up. For $20 you pop in for an hour or hour and a half and Coach Carlos gives one-on-one training - intense training. i barely made it through the first few workouts - and the money goes towards the kids boxing program. Every other lesson is free so you basically get a 60 or 90 minute private training session for $10. I know, right. Deal of the decade. 5420 Columbia Avenue, 214.282.7784.