On Wednesday, I took my first ever “functional threshold power” test. The FTP is a 30-minute test, using my CompuTrainer, which is designed to measure the average wattage (or power) I can maintain while cycling for 30 minutes (CP30). The above image illustrates the results of this test. (Side note: I don’t have a polar heart rate strap yet, required for CompuTrainer HRM, so the HR data is below, imported from my Garmin HRM file.)
Fitness tests are not new to me. I rowed crew in high school, and we had regular tests of our fitness on the ergometers (rowing machines), as well as 2 mile running tests. More recently, I’ve done some max heart rate and threshold heart rate tests for running. What I know about all of these fitness tests is that they are painful, but in a good way. They make your legs burn, while your lungs feel close to the point of explosion. This self-inflicted discomfort is worth it, however, because these tests are an important barometer of fitness, and an important mechanism to monitor progress in training.
Measuring results–or lack thereof
Determining one’s functional threshold can be done using either power (for cycling) or heart rate (for running or cycling). Regardless of your sport, these tests are important for all athletes–runners, cyclists, triathletes–who want to improve their performance for the next race day.
In addition to measuring performance and growth, these test numbers offer a mechanism to gauge effort for workouts of different purposes. For example, for a tempo effort, which is often described as a “comfortably hard” effort, I want to keep my power at about 80-85% of my FTP for cycling or max heart rate for running. For a long endurance run or ride, characterized as a long, moderate aerobic effort, I’ll want to shoot for about 65-75%, and so on.
Threshold numbers also offer a guestimate of what I’ll be able to hammer out for certain distances. For example, according to Simon Ward, of The Triathlon Coach, if I multiply my FTP number for cycling by .65, I get a sense of the power I can maintain for an Iron distance race. For marathon running, we can estimate that we’d be able to maintain about 75-80% of our max heart rate, or about 85-90% of our threshold heart rate.
By testing heart rate and power at regular intervals (say every 4-5 weeks), we can measure our improvement, or failure to improve, which could be a sign of a problem with the training plan. These results permit us to make smart adjustments throughout training to ensure that we are able to perform at our best potential on race day.
In other words: really helpful stuff for training and race strategy.
I think I’m going to puke
But, about 26 minutes into the hardest cycling workout I’ve ever done, I wasn’t concerned about what the results would tell me about my fitness. I was focused on HOLDING ON. I repeated my various go-to mantras:
“Don’t quit.”
“This is temporary. Push. Push. Push.”
“Don’t you stop. Don’t you stop.”
“You got this.”
When those failed me, I counted to keep focus, to keep my power up, and to keep my breakfast down. That’s right folks, I almost had a leaker. It’s been a while since any workout has made me almost throw up, and I’ve never felt like I might hurl from cycling.
When I described the workout to John, he replied, “That is AWESOME! Really, I’m serious. That is really, really good.”
While this might sound demented, I have to admit, I’m kinda proud of myself. I know I rode as hard as I could. I know I pushed every ounce that I could out of the workout. I feel pretty confident that I found the “number” that will guide my cycling workouts for the next several weeks.
How to do it–the bike
You can find your functional threshold (for heart rate and power) using the following steps. Please note, if you don’t have a power meter or a CompuTrainer, you can still do the test to find your functional threshold heart rate. This FTHR (sometimes referred to as Lactate Threshold, LT) is also a useful indicator of performance and to gauge intensity.
Step 1: Start with a solid warm-up that is progressive in intensity. Simon recommended using the “progressive intervals” course loaded into CompuTrainer, or doing the following warm up:
- 0-4 minutes – build to 70% of maximum heart rate (or 70% of maximum perceived effort)
- 4-8 minutes – build to 75% MHR
- 8-12 minutes – build to 80%mhr
- 12-15minutes – build to 85%mhr
- 15-16 minutes – build to 90%mhr
- 15-20 minutes – ride easy an allow HR to drop
Step 2: Prepare yourself for a grueling 30 mintes. Make sure you hydrate and take a gel during the warmup. You won’t be able to do either during the test if you are pushing correctly.
Step 3: If you are using a CompuTrainer, load or create a flat course that will allow you to ride for 30 minutes. (I used the 3D software to create a straight flat 20k course.) If you are creating a course, make sure to do so before starting your warmup. If you do not have a CompuTrainer, set your trainer’s resistance and your bike’s gearing to simulate a flat road.
Step 4: Punish yourself for 30 minutes. When starting, Simon recommended that I shoot for about 90% of my maximum heart rate for the first 15 minutes, and then for the second 15 minutes push harder if I could, or hold on. You don’t want to go at 100% effort right out of the gate. It will be impossible to maintain that for 30 minutes.
- My heart rate file. Notice the high, steady flat line. That’s the test.
Step 5: Save all of your data for the 30 minute test – average watts, average heart rate. This average equals your functional threshold number – whether that is power or heart rate. Now, you can use this information to guide your training for the next 4 weeks or so. Then, after 4 weeks, do it again to see how you’ve improved.
How to do it – the run
For running, you can perform a 20 minute functional threshold heart rate test that will give you a good idea of your “redline,” or the point at which you shift from aerobic to anaerobic functioning. This difference matters because it affects how your body processes fuel, and gives you a sense of how long you can maintain that effort (at that heart rate) before bonking.
Step 1: Warm up. As with the cycling test, make sure you have a good solid warm up, that works through progressive levels of effort. 15 – 20 minutes is good. Make sure you hydrate during the warmup, as you won’t be able to during the test.
Step 2: Select a flat route, or use a treadmill. Run at the fastest pace you think you can withstand for 20 minutes. It’s important to avoid going out too hard, and getting a sense of this “magic” pace might take some work. Be sure to use a heart rate monitor to get an average HR for the 20 minute test. That average equals your functional threshold (again, sometimes referred to as your “lactate threshold”), which should be about 90% of your max heart rate.
Step 3: Save your average heart rate information for the 20 minute test. (Be sure to reset your monitor when you finish your warm up so the warm up heart rate does not affect the test heart rate.) Now you have information you can use to guide your running efforts for the next 4 weeks or so. After 4 weeks, do it again. The best time to do these tests is at the end of a recovery or low mileage week.
You can also perform a test to determine your max heart rate. But, for runners, this is a risky proposition, as it requires you to run all out, as fast as you possibly can for a mile. Running at these types of speeds for a mile can invite injury. So, I don’t recommend it. Rather, from your threshold HR, guestimate your max HR for running. (You can do the same with your threshold info from the cycling test).
Testing is difficult, but it’s a challenge worth facing if your goal is improvement in performance, efficiency and speed. What types of fitness tests do you do? How do you use this information?
