We get it. Not everyone loves to run. Common complaints: It hurts my knees, it's boring, I've stopped seeing results. Thankfully, there are plenty of other ways to get a heart-pumping, calorie-crunching workout. In fact, by upping the intensity and speed of your exercise routine, you can turn almost any workout into a cardio workout, says Brian Gallagher, co-owner of Throwback Fitness. Here are 18 ways.