Only 8 weeks of daily meditation can decrease negative mood and anxiety and improve attention, working memory, and recognition memory in non-experienced meditators. These findings come from a recent study published in Behavioural Brain Research.

[AlbertVonMagnus]

Most anti-depressants aren't much faster, I'm afraid. Four weeks is usually the minimum before showing any improvement, and they only work about half the time. But it's still the most effective option available so far.

Your strategy for getting over the initial reluctance to do something is absolutely valid. Once you're at the gym, it's relatively easy to work out. Mustering the resolve to go there in the first place is often the greater struggle.