I've been seeking to increase the amount of cardio I do and keep things interesting so it was a no-brainer when this GMB product came on the market. Not only is this program interesting, but it sneakily challenges endurance in all sorts of ways. All the moves are easy to regress or progress (I have yet to need to do that) and mentally challenging enough that I don't realize I'm working, so I get a great workout. There is always at least one especially fun move and sometimes I get lucky and all three moves are fun, like today's video. I am primarily focused on strength training, so it's interesting to see these workouts challenge my strength in new ways.