When RWH came out I did it exclusively for one month. Most of the RWH are shorter in length compared to Cathe's other workouts. I worked out 4-5 days a week, one workout a day, no doubles. My goal was to lose fat. I did not change my diet at all. I didn't lose an ounce and I felt wiped out. Fast forward to now. I am now in a mindset where I am really focusing more on my diet, nothing dramatic, just watching overall cals and cutting back on processed foods, but I still eat pizza once a week, still have an occasional can of Coke. In the past 5 weeks I have lost 7 lbs. My workouts have been much easier than I usually do. I have been doing the Butt Bible, the upper and lower body workouts only once a week. I walk/jog on my treadmill once a week. The other days will either be a short cardio, usually a RWH HiiT workout and the other whatever I feel like. I workout 4-5 days a week still. For me I can't do super intense workouts and cut cals at the same time. My workouts suffer and so do I. On the flip side, I feel you need a calorie surplus to gain muscle, but not necessarily to gain strength. I still feel strong. This past week I took a week off of any planned workouts b/c work has been busy, but I still did a treadmill walk/jog, I also did RWH Circuit Upper Body No Blast premix (didn't feel like jumping...loved that premix by the way) and I've been sampling some Barlates workouts. I'm feeling the need for more strength training (just listening to my body) and plan on starting that next week. But back to the original question, my workouts are generally 30-40 minutes except for my treadmill day which tend to be a bit longer. So intense workouts 4-5 days a week, not watching diet resulted in fatigue and no weight loss. Less intense workouts 4-5 days, still in the 30-40 min range + watching diet resulted in 7 lb weight loss and feeling much less fatigued.