This routine is meant for improving condition and muscle tone while losing fat. The workouts are short so that they can be done before/after work, for those with a busy schedule. The 20 mins cardio at the the end of the first 3 workouts are high intensity interval trainings: perform 5-8 cycles of 30 secs at 50% intensity followed by 30 secs at maximal intensity. 5 mins warm up and cool down must also be performed. Feel the burn! Choose exercises that allow you to perform this fully, but do try to vary them. I would advise rowing on your Pull day. Boxing on abs day consists of 5 bouts of 1.5 mins with 30 secs rest in between. Keep moving on your feet and throwing punches, but don't go all out for the duration. Cardio on abs day should be low intensity, e.g. jogging.