Speed training

[preston32]

Hi, I've been training for a 100 mile ride for a few months now (it's not til next year so plenty if time). I've been doing 1 3-4 hr ride per week, 1 2 hour ride (medium pace) per week and also a cpl of interval sessions per week. My endurance has improved loads but my 'cruising' speed has hardly changed. Should I be doing longer intervals than 5 mins? If so how long?

 

[RapDaddyo]

If your objective is to increase your aerobic power, you don't need to be doing 5min intervals. You would get better results with aerobic intervals of at least 10mins and preferably even longer (e.g., 20mins). It's not that 5min intervals will set you back, it's that they will be less effective than longer intervals at increasing your aerobic power.