You can't always get what you want

But if you try sometime, you get what you need. After Monday’s epic Tuesday was a day of rest slumbering quietly at my desk at work. Wednesday I cycled in which gave me a gentle 10km workout on the fixie and Thursday a big session in the gym.
Interestingly (well, to me anyway) I normally warm up with a 2000m row, with the intention of completing it in under 8:30. Which I normally manage pretty easily. Today my legs were stiff so I thought I’d manage my HR rather than effort. By keeping my HR “in the zone” (129 - 149) I managed 2500m in 10:40, and wasn’t too tired at the end. Which just goes to show that exercising at a more consistent rate for longer gives a better result. I know this isn’t news, but its good to see it in action.
Now, what I don’t know how to do is to translate this to riding the bike.

For example on Monday my HR shot up to 170 which is 95% max, I assume on one of the steeper climbs (I wasn’t watching it) and averaged 134 (74%) which is fine. The question is when presented with a massive climb how do you stay out of the red, or is it more important to maintain a good average and not worry about the peaks and troughs. Conversely I have noticed I can punt along at 40kph on flat terrain with a HR of 120 (with the wind!). I’m sure I’ll work it out.