Is Afterburn considered cardio or strength or both? I'm wondering how often I can do it along with Butts & Guts. The other day I did B&G for the first time. The next day I was feeling fine so I did Afterburn, then my butt was sore for 4 days. I thought the soreness was from Afterburn but maybe it just reworked the muscles from B&G. I did B&G again 2 days ago and this time I was sore right away and still am. I love that I'm sore because it means I'm working those muscles but I do best when I have a workout to do everyday to stay consistent. Should I continue my schedule if I'm sore or take a break?