By Anna Wallner and Kristina Matistic

Anna Wallner and Kristina Matisic

Did you overindulge this holiday season? Looking to shape up in the New Year? Treadmills are considered one of the most effective pieces of exercise equipment when it comes to burning calories. Plus, studies have shown they are the least likely machine to gather dust.

Here's what to look for when shopping.

• The most important tip is to bring your running shoes and test various models in the store. This is a must.
  
• Check the motor size. Look for a minimum of "two continuous horsepower." If you plan to mainly run on your treadmill, a three-horsepower motor is even better.
  
• Hit the deck! It should be at least three-quarters to one inch thick, 20 inches wide and 55 inches long. Runners will need a longer deck than walkers.
  
• Make sure the machine doesn't wobble, and it should be shock absorbent.
  
• Check the program options and display for ease of use. We like a good selection of programs to keep boredom at bay. And we don't like treadmills with hydraulic pistons — you can't change the incline while running.
  
• Treadmills tend to break down more than other exercise equipment, so check out the warranty. The frame should be covered for lifetime and the motor for 10 years or more. Parts are usually covered between two to five years. But labor can range from a year to only 90 days. If that's the case, it's one of the few times you might want to consider buying an extended warranty, to cover any future repair costs.
  
• You don't need a gym-quality treadmill. These models are heavy duty because they take hours upon hours of abuse each day.
  
• We don't recommend buying a treadmill over the Web or through an Infomercial. You really need to try out the equipment.

(Anna Wallner and Kristina Matistic host The Shopping Bags.)