There are many bells and whistles that help enhance your
cardio experience. Many running treadmills with an LED display or LCD display inform you of important stats as you work out, such as calories burned, distance travelled and time spent exercising. Built-in heart rate monitors are often located on the handles to let you know when you've hit your peak, while various running surfaces are sized to give you breathing room as you run. Hydration is an equally important factor when it comes to working out, and as such treadmills with cup holders make sure you can keep going. Most machines have a specified weight capacity so that everyone has the chance to work out.