Whether you believe that global warming is a real or if it is -- as some people claim -- the greatest hoax ever perpetuated on mankind, it goes beyond debate that we're once again experiencing some unseasonably warm January days. Politics, science, and personal beliefs on global warming aside, these warmer days make for some bonus outdoor workout weather.

A nice, brisk jog is always a great way to get the heart pumping and burn some calories. Just as effective as jogging, say Duke University researchers, is taking an equally as long walk. Based on their findings, walking 10 miles a week burned around 1,200 calories, which is just about the same amount burned from jogging the same distance.

Because it took the research volunteers an average of two hours to jog the 10 miles in a week and about 3 hours to walk this distance over the same amount of time, researchers concluded that duration appears to make up for the difference in intensity.