Oxygen, absolutely. Do NOT get Fitness Rx! They are way too blatant about pushing their sponsors' supplements- it makes me think everything in their magazine is suspect, as well as poorly written. And I know whereof I speak- I was given a subscription to it, so have a lot of their issues.
But really? As someone who has about 6 fitness magazine subscriptions, if you really want the info in the mags, go to their websites. But if you don't really need the info, spend the time working out instead of reading.