Each circuit will last approximately 90 seconds. Rest for an additional 90 seconds and then repeat two more times in this fashion. This tri-set of exercises will leave your heart pounding and your body feeling invigorated! ... Plus, it's only one (indestructible) item that you can take with you on trips/vacation to keep your exercise routine going. Posted by: | Nov 14, 2007 6:09:29 AM. Kettlebell training, plyometrics, deadlifts, squats and most of the high intensity ...