Three main things with eczema:
1) it can be a seasonal disease. for the most part it gets better in the summer for most people but not for everyone that's why light treatment has been advocated for refractory cases.
2)moisturization is VERY important. any over the counter with alpha hydroxy should be used frequently to keep irritation to a minimum. you may find irriation after working out so it's important to moisturize prior. staying hydrated helps but direct application is the main thing.
3)topical steroids are the best treatment to control flare ups. the over the counter (OTC) stuff isn't very good. you could try hydrocortisone but my guess is you have already tried. if you haven't give it a shot. this with the moisture treatment may make it bearable for you. if this doesn't work get a script from your personal MD for Elcon cream. its the best. its a once daily applied cream that should give you all day relief. I would only use it when really needed as you can get tachyphlaxis (decreased results) with chronic use.
I hope your's is mild because this can be very tough to treat. Luckily you only have it on your hands. this is the most manageable situation.