How to use a power meter to test yourself and set personalised training zones... By Phil Mosley
Introduction Once you’ve trained with a power meter, you’ll never want to go back. Without one it’s nigh on impossible to accurately measure your performances, strengths, weaknesses and training intensities. Power meters are an integral part of our triathlon coaching process. It’s hard to appreciate all the benefits without experiencing one yourself throughout a season, but take it from us - there are lots. Here we’ll talk you through some of the most important ones and how to utilise them.
3 Ways To Train Smart
1. Know Your Level With a power meter you can see exactly how bike-fit you are at all times, regardless of variables like weather, terrain, hills, mechanical-efficiency or weight. It’s there right in front of you - a simple number that shows the result of all your pain and effort. The reality of these numbers can come as a shock to some people. It’s not uncommon for triathletes to buy a power meter and suddenly realise they are significantly better or worse than they thought. Sometimes a power meter can help people realise that it was their bike or their poor aerodynamics that slowed them, rather than their legs. Knowing your level at all times keeps you grounded in reality, as well as helping you pinpoint areas for rapid improvement. This is important for our triathlon coaching, as it helps us set our athletes realistic expectations.
2. Test Yourself With a power meter you can perform a simple test that pinpoints your triathlon cycling ability. It’s called a CP20 test and the CP stands for Critical Power. Start off with a 15-20 minute warm up with five 20-second efforts thrown in. Now you’re ready to start the test, which involves riding for 20-minutes at the highest sustainable intensity you can manage. Your cycle computer should give you your average power for the entire test. We’ll discuss ways to use this figure in the next point, but on it’s own it’s a useful benchmark that’s worth re-testing every ten weeks. At My Pro Coach, we do this as part of our triathlon coaching process. This CP20 figure is an even more accurate measure of your ability when viewed alongside your weight (power to weight ratio) and your drag coefficient (power to drag ratio). You can multiply your CP20 by 95% to get a good estimation of your Functional Threshold Power (FTP), which is approximately what you could maintain for a 1-hour time-trial.
3. Set Your Power Zones One of the beauties of a power meter is that you can train at specific intensities that mirror the demands of your upcoming races. Before you do this, you need some training zones that are based on the results of your CP20 test, as described in the point above. Multiply your CP20 result by 95% to get your FTP. All of our triathlon coaching clients use these zones. You can set yours using the guidelines below.
Set Your Own Cycling Power Training Zones Once you've done a CP20 (as detailed above) you can start setting your own training zones...
Endurance Zone Intensity: 65-80% of FTP Benefits: Progressive training at this intensity can improve endurance and boost fat-utilisation. It is similar to Ironman race pace. It is easy enough that you should be able to recover day-to-day from most sessions. Sample Session: Ride 3 hours in the Endurance Zone
Sweetspot Zone Intensity: 86 to 92% of FTP Benefits: This intensity helps boost lactate tolerance, but is light enough that you can recover within 24-hours from these types of sessions. It is a particularly useful intensity for Ironman 70.3 training. Sample Session: 3x10mins in the Sweetspot Zone with 60seconds rests.
Functional Threshold Zone Intensity: 97-103% of FTP Benefits: This intensity is known as FTP (functional threshold power) and equates to your best power output for a 1-hour time trial. Training at this intensity can boost lactate tolerance and is particularly relevant to Olympic distance triathlons. You might need a couple of easy days after these workouts. Sample Session: 10, 9, 8mins all in FTP zone, with 2-mins recoveries.
CP20 Zone Intensity: 105-110% of your FTP Benefits: This is slightly harder than you’d ride in a sprint triathlon, but it’s still a relevant training intensity for them. Sample Session: 30mins as (20secs in CP20 Zone, 40secs in Endurance Zone)
CP5 Zone Intensity: 100% of your CP5 (your best power output for a 5-minute time trial) Benefits: CP5 stands for Critical Power 5. You would use this kind of power output (and more) when riding up hills, overtaking or accelerating out of turns. Sample Session: 5x2mins at CP5 with 3mins recoveries in the Endurance Zone