New Habit = Old Habit

I do my old habit, again! It deserves for miserable consequences. My skin gets darker and on several parts of my body get blemish that cannot disappear for years (as the relic on my body still exist though the last time I did it was a year ago). My reddish Indian skin - I know nobody believe this statement, hahahaha…. - disappears, turn into scaly dark skin. Moreover, my friends have called me Sudanese (you must know Sudan!) and what happens on my skin affirms what they’ve said. It means I must prepare myself because they will say it more freely and unhesitant *sigh*
Guess, what my habit is?
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Yup, I swim. I do it every week on Tuesday or Wednesday after lunchtime. Weird, huh? Yeah, I know it. But, it is the time I like most because not so crowded.