Okay, that's kind of what I'm getting at. Although, being a noob not sure what threshold power and VO2Max power are (I do know what VO2Max means though) or how to measure them without fancy gizmos. I've been riding the road bike for about 6 months and I've recently started doing my multi-climb route 2-3 times a week. Is steadily climbing those hills over and over "building a solid base"? If so, how do I know when it's okay to work on the anaerobic capacity? Although, for what it's worth, most of the time I am in an anaerobic zone when climbing these hills and even max effort at times.