Q+A: What’s the best strategy for climbing hills?

Q. There's a lot of debate about how much effort to put in on bike climbs during races. What's the best strategy?

A. The key to pacing hills has everything to do with the size of the hill and the length of the race. Your muscles work on the basis of the critical power (CP) model. CP - or critical velocity (CV) for running - is easily understood as the highest power you can maintain, when muscle energy supply and demand are well balanced.

Going harder involves using an additional store of energy maintained by the muscles, which you can think of as a battery. When the battery goes flat, you'll start walking or freewheeling and will lose many minutes trying to recover.

There are ways of calculating your exact CP or CV, but if you've done a few races you'll have a feel for this level of effort; you'll find yourself thinking, "I can do this for a while, but if I go any harder, I'm going to tire out quickly." It lies close to your 20-40K time-trial power/effort, or 10K run pace/effort.

Your goal is to remain under this level of effort, so that your muscles do not become excessively fatigued. In sprint or Olympic-distance races (and on short hills), you can afford to exceed CP/CV as long as you don't do it for minutes at a time.

Climb the hill steadily, with the sensation of increasing effort as you proceed. You'll know you have it right if you crest the top and don't feel you need to recover from the effort. In contrast, races of half-Ironman distance or greater (and longer hills) require a more careful approach.

You must preserve that battery at all costs, or you will have a long walk ahead. Approach the hill at a steady effort, and shift gears or slow down to maintain your appropriate race effort. If you find yourself exceeding CP/CV effort, you are working too hard and you will pay later in the race. The place to spend that effort is in the back half of the run, when everyone else starts walking.

Dr Philip Friere Skiba

Dr Philip Friere Skiba  is a physician specialising in sports medicine, and is the CEO of PhysFarm Training Systems. He works at the University of Exeter, in the department of sport and health sciences. He has trained a number of amateur and elite multisport athletes, including world champions Joanna Zeiger (Ironman 70.3) and Catriona Morrison (duathlon). You can read more at physfarm.com.