Intensity - How hard should the intervals feel?


These short intervals are very powerful and research shows they often lead to enhanced 'bang for buck' relative to long intervals. The work interval portion should be done at around your L6 power output. Don't focus on HR during these and just let it do what it does. The feel for the L6 should be 'strong' on the first rep, and feel 'hard' to 'very hard' by the last rep, and definitely in the 'very hard' range by the last rep of the last set.

An important point to note is that you should always leave your HIIT sessions like you could do one or two more. Never go to failure or complete exhaustion.

"The most important training session is the next session."


@phil again... your advice is prudent. Exactly the mindset you should aim for.

  • What's in front of me to do? Pace appropriately.
  • Focus on the 'on' rep.
  • Use the recovery 'off' rep to truly recover as best you can, even if that mean hardly moving your legs around or walking in the run context.

I have Intervals on my schedule:

  • 4 x 6 x 1′ of 30/30s
    (2′ recovery between sets )
    • 30″ on (quality focus)
    • 30″ off (just turning over legs)

My question is: How hard should I do the 30s both, hard intensity and the recovery? I realize the program tells me pace/power/heart rate targets but how hard should it feel? Do you have a rate of perceived effort table or something?

Thanks, M

I find that the perceived exertion and max heart rate see a gradual climb through the sets. Thus, what might not feel “very hard” to start with, increases in difficulty, as the number of intervals and number of sets completed increases. I look to sit in the power range Athletica suggests, and use the first set of intervals to gauge where abouts I’ll aim for in that range, for that session. I’m always aiming to complete all the sets; thus if I have more sets I might be towards the lower end of the suggested power range, with less sets I might aim higher up the suggested range.


Oh and recovery I see as exactly that. It’s so I can recover to hit the power in the next “on” interval or so I’m ready to go again by the next set. I tend to keep recovery power low, rather than seeing it as a way to inflate the session power average, by riding too hard during recovery periods.