by Hunter Allen, PCG Founder/CEO and Master Coach
A power meter, as we all know, is a measuring tool. It measures the torsion (twisting) of a bicycle part that has been twisted as a result of your pedaling. This can be measured in the “spider” (the part between the chain rings and the crank), in the hub, on the twisting of the chain itself, or in the crank arms or pedals.
Power is torsion multiplied by angular velocity (angular velocity in cycling is how fast you pedal). Power is output in watts. The typical trained cyclist can average 250 watts for one hour, but what that number means in the real world is dependent on rider weight. For example, two cyclists producing 250 watts for an hour can have drastically different power to weight ratios:
- A 115lb (52kg) cyclist will have a power-to-weight ratio of 4.8 watts per kilogram
- A 180lb (81kg) cyclist will have a power-to-weight ratio of 3.0 watts per kilogram
Wattage is the measure of work that you can do on a bicycle. While heart rate can measure intensity of effort, it is dependent on rest, hydration of the rider, outside heat, and humidity. Heart rate is a response mechanism to work. Wattage is the “dose,” and heart rate is the “response.” If you’ve been training with a heart rate monitor, you’re basing your training on a response. But what causes that response? Why did your heart rate go to 150? Was it because a dog just chased you? Was it because you just did a hill sprint? Was it because you’re just hyped up as you sit on the start line waiting for the race to begin? Heart rate gives us some information, but it doesn’t tell you how much work you’re doing. A power meter does.
Once you’ve forked out the dough for your new power meter and gone through the laborious process of installing it on your bike, calibrating it, charging the computer, and figuring out how to use the buttons, you might ask yourself, “How do I use this thing to improve my cycling?” That’s a great question, because improving is exactly what you want to do with your new training tool.
Click through to find out how…
A power meter won’t instantly make you a faster rider like putting on that new set of fast wheels or dropping a pound off your bike with some new carbon fiber widget. To get the benefits of a power meter, you’re going to have to think, understand, and utilize all the information it provides to you. The power meter collects a tremendous amount of data (five to seven channels of data at one-second intervals), and you’re going to have to make some sense of it in order to ultimately improve your cycling. I’ve come up with some basic steps to get you started on the fast track to training with a power meter. Let’s get going!
Step 1: Collect Data: Your first mission is to simply ride with the thing on your bike and download your data from every ride. Every ride is important, and every download is key to your understanding. Don’t change your training for the first week or two; just follow your normal routine and collect the data. These downloads will tell you how much time you spend in your new power training zones, at what wattage level you consistently pedal, your preferred cadence, how many kilojoules it takes before you significantly fatigue, etc. Your goal in this first step is to learn some basic things about yourself as a cyclist to apply later in your training in order to improve.
Step 2: Test: The second step in the process is to determine your functional threshold power (FTP). FTP is defined as the highest power a rider can maintain in a quasi-steady state without fatiguing for approximately one hour. There are many ways to find out your FTP, but the best one is to go out and hammer for an hour and see what you can do. Unfortunately, as you might already know, this is a painful process. You’ll need to test for your FTP many times in the future, as it is one of the best ways to see how much you have improved over time. (For all you “shortcutters” out there, do 20 minutes as hard as you can and then subtract 5% of your average watts; this will give you a very close approximation of what you could do for an hour.)
Step 3: Establish Power Training Levels: Once you know your FTP, you can then determine your power training levels. Power training levels are anchored around your FTP; with your FTP as 100%, the rest of your training levels can be defined. Understanding what level you’re training in is critical to help you create the training response you want. If you want to improve your anaerobic capacity, make sure your intervals are between 120-150% of your FTP, and rest assured you’re training in the correct level to induce training adaptation.
Step 4: Power Profiling: Figure out your relative strengths and weaknesses. Dr. Coggan and I initially created the power profiling chart to help riders compare themselves with the best riders in the world and with their one racing peers. However, it ended up becoming a very important tool in determining the type of riders we are and what areas we need help in. Are you really a good sprinter? Are you really a time trialist? By comparing your wattages with your power profile, you’ll be able to see your exact strengths and weaknesses, as well as what type of rider you are.
Unfortunately, figuring out your power profile involves more testing! You’ll need to test your best 5-second, 1-minute, and 5-minute wattages. These represent your neuromuscular (level 7), anaerobic capacity (level 6), and Vo2 Max (level 5) wattages, respectively. It’s easiest to test these on a day when you’re fresh and not tired from a long block of training; you’ll crack out your best numbers when you’re rested.
The importance of learning your power profile cannot be understated. Your relative strengths and weaknesses will determine your training plan as you go forward to attack and improve your weaknesses, as well as your strengths.
Step 5: Wattage-Based Workouts: The final step is to adapt your old training ideas, habits, and patterns into wattage-based ones. Since you’re now training with your power meter and using wattage to guide you, you’ll want to change your intervals to wattage-based ones in order to elicit the greatest training adaptation.
Training specifically in your current training levels will guarantee that you are using your time most efficiently. When training in levels 1-3, look at your average power for the entire ride to make sure you’re training correctly, and don’t kill yourself by trying to pedal in a narrow wattage range for these lower levels. If you’re doing an endurance ride in level 2, don’t attack the hills like it’s the world championships and then putt around the rest of the time to keep your average wattage in the level 2 percentages. When training in the more intense levels 4-7, you’ll want to hold your wattage as best you can in the level you are training. These intervals are shorter and more intense, and they’ll require focus in order to maintain the correct wattage and keep yourself honest in your effort.
Training with a power meter is about results, not simply learning how to do it. Does this tool work? No, a power meter doesn’t work; you work. If your training/racing/cycling is to change (improve), you must be willing to change first.
Hunter Allen is a USA Cycling Level 1 coach and former professional cyclist. He is the coauthor of Training and Racing with a Power Meter, codeveloper of TrainingPeaks’ WKO software, and CEO and founder of Peaks Coaching Group. He and his coaches create custom training plans for all levels of athletes. Hunter can be contacted directly through www.PeaksCoachingGroup.com.