The Wonderful World of Power Testing

Lets be honest, fitness testing can be an absolute minefield. You’ve just done a ramp test, your friend has done a 20 minute test, and someone else has done an 8 minute test. But what does it all mean? Does it matter what everyone else is doing? Should you be comparing yourself to others?

Why don’t we start by talking about why testing is important. Fitness testing allows you to set benchmarks for current levels, set training zones for practical application, and set physiological goals to help focus your workouts and planning. In years gone by you needed to have access to a sports science laboratory to complete any form of fitness testing, but now with the advent of power meters we have access to more readily available data through field testing. There are still a large number of benefits of using sport science labs for testing, not least measurements for your VO2 Max and Lactate Thresholds. However, this article will concern field testing that you can complete with just your power meter, and practical application of those results for use in training.

Functional Threshold Power Testing

You are most likely considering doing some power testing, to check your maximum power for a certain duration. But have you ever stopped to consider what that figure actually means? For most people, the bulk of any fitness testing they do will be to put a figure on their Functional Threshold Power (FTP), which can be defined as the maximum power you can sustain in a quasi-steady state of between 30-70 minutes, or for approx 40 kilometres. When Dr Andrew Coggan first introduced this metric to the world, it was designed to be a real world solution that was roughly equivalent (though not the same) as your lactate threshold… Hence the name ‘functional’ threshold. There is often some confusion around defining FTP, but the fact is there is no fixed duration for which a power figure can be applied, and when dealing with FTP we are usually talking about estimates!

Estimating FTP is not a problem, but this is where the confusion can sometimes arise and riders can become too bogged down in the detail. FTP can be derived from various different test protocols, on different power meters, in different settings, which makes it very difficult to compare to other riders and I would not encourage 1-to-1 comparisons of these figures. The most important thing with testing for FTP, is knowing your test protocol and your results.

The most common method of testing for FTP is the classic 20 minute test. Warm up, do some openers to prepare your legs, then 20 minutes maximum effort during the test. This is typically used to calculate FTP by taking 0.95x the power for 20 minutes. This test does however have it’s flaws, more anaerobically inclined riders might overestimate their FTP during this shorter test which is why certain protocols will have the rider do a shorter maximal effort a few moments prior to the 20 minute test, to minimize the impact of the anaerobic system on the result. Aerobically strong riders may under-estimate their FTP, especially if their time to exhaustion is particularly high. In reality, your FTP is likely to sit somewhere between 92%-97% of your 20 minute test result. Now this is the important part… Providing you keep your testing protocol constant, your estimate of FTP will follow the same parameters and therefore be the most accurate indicator of your FTP, regardless of which protocol you use.

Keeping your test protocol consistent is critical to measuring changes in your Functional Threshold Power, and this is particularly important when using FTP to set your training zones.

Key Points:

• Choose an FTP test, and stick with it
• Set a baseline and measure changes against it
• Don’t compare yourself to others, there are too many variables!

Should you do any other field testing?

Short answer? Yes.

You should absolutely do some shorter duration testing in the field, as this will help you to understand your strengths and weaknesses as a rider. By knowing your areas for improvement, you can target your training towards your goals and ensure you have the best chances of success. Ensure that you measure changes in these by re-testing at certain points in your training plan, this will help guide you on whether your methods are improving the systems you were targeting.