You should wear clothes that are loose and comfortable. But if you are running or biking, avoid wide-leg or loose pants that could get tangled up in the pedals or your feet. Consider these options for comfortable, year-round workout clothing for both men and women.
Girls in their workout gear : theCHIVE
Nothing can ruin an outdoor workout faster than getting soaked in the rain or caught in a strong wind. And keep the weather in mind if you're exercising outdoors, and dress appropriately.