In terms of intensity, probably, The Ranger program is the most intensive program on earth. It demands discipline and dedication. But the program is carefully designed so that you can handle it properly while you are working in a company with some pain, dedication, and discipline. So, the answer is yes and no. Yes from an intensity perspective and no, from the self-improvement perspective. Challenging oneself is an ontological phenomenon. You have to accept that idea and its consequences before enrolling.