Quick Tip: Get a Good Workout at a Hotel Gym
Here's a sample workout you can do in a hotel gym: "Train Like A Triathlete." I like this workout because all it requires is an elliptical trainer, a bicycle, and a treadmill, all of which can be found in most bare-bones exercise facilities you might find yourself using while traveling. You'll significantly boost your metabolism and burn calories with this routine.
Bike: Next, move from the elliptical to a recumbent or upright bicycle, where you'll ride at your maximum sustainable pace for 10 minutes.
Treadmill: Finally, get on the treadmill and begin with a slow jog, then bring the incline up by 1.0 every minute, until you can't run up the simulated hill any more. At that point, slow to a walk and cool-down.
For more about staying fit on the road please see my Quick Tip about keeping fit while traveling.