When the weather isn’t good for exercising outdoors I run on a treadmill, sometimes for well over an hour. No matter how many fans are blowing and how many windows are open at the gym, I seem to sweat 10 times more when I’m running indoors than when I’m running outside. I always cue up an inspiring playlist on my iPod – especially for long indoor runs – but lately I’ve been having a problem with sweat getting into my ears during the runs and wondered if sweat in my ears (ew!) might cause an ear infection. [...]