Here's yet another killer combo exercise you can do on the BOSU. So hands on the BOSU, either flat or gripping it. You're going to bring one knee to your elbow at the same time as doing a push-up, so it would look like this, then back up. Then of course, you want to do it a little bit faster so you go down, up, switch legs. That's definitely something that's going to get both your upper body, your core and your heart rate going, and that is another killer combo workout, you can do on the BOSU.