Running with Power is a new book from elite US running and triathlon coach Jim Vance. The book is described as the complete guide to power meters for running.
Power meters have been used extensively in cycling for a number of years and provide key data used to improve training and racing performance. It was only a matter of time before such a device was used for running. The book clarifies two key points. Firstly, bike power meters are typically attached to the bike so are measuring the watts used to push the bike in a forward direction. Running power meters are obviously attached to the person, usually as a chest strap (e.g. Stryd Power Meter), so are picking up data in 2 or 3 dimensions, potentially providing extra information relating to vertical oscillation, running efficiency, etc. Secondly, power provides a truly live output metric which gives objective information unaffected by terrain or conditions. Heart rate gives an indication of how hard you’re working but there is a time lag between effort level and resulting heart rate. This may not be an issue on a steady run but is significant during an interval session or in varied conditions or terrain. Similarly, pace or speed measurements (typically GPS-based) give an indication of relative performance but do not take into account the conditions of e.g. a windy day or hilly course.
Running with Power suggests that power meters will revolutionise the way runners train and race in the same way that they have in cycling. Clearly, the more casual runner may have little interest in the data provided by such a device but the serious athlete who is looking to improve performance and get the most out of their training may have a lot to gain. The book explains in detail the significance of terms like Functional Threshold Power and Normalised Power and shows how power measurements can be used to make training more effective. Inevitably, it’s a bit “text-booky” in places and I had to re-read a few sections to really get to grips with the significance of what Jim says. I’m still a bit confused by how the ratio of kilojoules to kilocalories is “complicated”. In simple energy terms, I thought it was a fixed ratio but he relates kJ to running efficiency, which is what causes the complication (and in my case, confusion!). Still, that’s a minor criticism. I liked the use of power zones in training. This is more sophisticated than the simple ones used for training with heart rate, particularly at higher intensities. I also liked the way he quantifies training stress scores and relates them to injury risk and effective tapering towards events. The book provides an appendix with an extensive series of specific phase training plans, which look very good.
Overall, the book lived up to my expectations in understanding how using a power meter can aid training and performance. It really does look to be the next step beyond heart rate and GPS speed/pace measurement , particularly for the more serious athlete. Apart from the new hardware available to make power measurements for runners, the latest software available helps reduce the time you need to analyse the data. After all, I’ll assume you want to spend more time training than looking at a computer screen!