END : END - Endurance Miles: Endurance Miles help increase or build the aerobic system and prepare the body for higher intensity training later on. Endurance Miles are the cornerstone of your endurance training and will be incorporated into your training year round. Your END ride heart rate and wattage averages should fall within your Endurance Stage (Zone 2) in order to improve your aerobic energy system. Your zone 2 levels equate to an HR below 83% of your LT HR and a wattage of 56%-75% of your FTP. We want you within this range 95% of the time on your Endurance rides; while you may find yourself outside of your Endurance zone at times, do your best to remain within Stage 2 upper and lower limits the majority of the ride. Cadence for Endurance Miles should be 80-100. PE should be 2-3 out of 10.