We've posted once or twice before on Functional Threshold Power (FTP), and the importance of knowing both power zones (for biking) and heart rate zones (for biking and running). Today, we're going to revisit FTP, and give you a few quick tips on how to begin training with power. While the majority of FTP philosophy discussed here applies to both indoor and outdoor cycling, this guide's main focus is on the indoor rider.
WTF is FTP?
Simply put, FTP is your body's ability to consistently maintain, or "put-out," the highest level of power (measured in watts) over the course of 45-60 minutes (though we usually test in 20 minute increments). You can imagine power, or watts, as a number found by multiplying your speed (cadence) by your resistance. So, if you hop on the bike with very little resistance, but pedal very, very fast, your power output will be low. Conversely, if you load up the resistance but can only pedal at 30 RPM, your power output will be low. To get the most efficiency out of your pedal stroke, and make the biggest gains in your overall fitness, you will want to find the right balance between resistance and pedal stroke to maximize your power output.
I ask my students all the time, “what’s the difference between a sprint and a hill?” Do you know the answer I usually get? “Resistance, right?”
For new riders, that’s a good guess. It makes sense that the steeper you imagine a hill becoming, the more resistance you need to mimic moving up that hill. In fact, even Spinners who have been taking classes for years often answer the same way. And to be honest, at the end of the day, they're all half right, but resistance is only one part of the equation.
Just as important as resistance is your cadence. Over the years, many indoor cyclists begin to develop the habit of using higher and higher cadences in their spin classes. Many participants do not ride outside, and therefor don’t have a full understanding of how cadence needs to shift on different terrain. Others are under the impression that a high cadence class with low resistance is the only way to prevent “getting bulky legs” (the reverse is actually true). Some even get use to speeding up to a point that the bikes fly wheel does most of the work!
Ken Presutti is a certified ChiRunning instructor, ACE Personal trainer, Spinning instructor, and coach. This blog is a mix of new articles and posts from his original blog, Overkill is Underrated.