4DP™ / Full Frontal Fitness Test FAQ

Q: What is 4DP?

Exclusive to The Sufferfest, Four-Dimensional Power™ (4DP) uses four key performance metrics—Neuromuscular Power (NM), Maximal Aerobic Power (MAP), Functional Threshold Power (FTP), and Anaerobic Capacity (AC)—to determine your rider type, identify your strengths and weaknesses, and create your comprehensive 4DP™ profile. Most importantly, the app then personalizes all of the power targets to match your unique profile, making them more effective than those based solely on percentages of FTP.

Q: Can you tell me more about those four metrics?

Sure. But even better - listen to Coach Neal Henderson and Sports Physiologist Mac Cassin explain them. 

Q: Why is this better than training with FTP-based workouts?

Most other training apps only use your FTP to set your power targets in workouts. For example, sprint efforts would be set at 200% of your FTP, while VO2 efforts would be calculated at 105% of FTP. The problem, however, is that FTP only measures your sustained, aerobic power. It doesn’t tell you anything about how well you can sprint, launch repeated attacks, or take a flyer off the front. Two athletes can have the same FTP but have very different capabilities at higher intensities. Training apps that just use percentages of FTP to set power targets are making assumptions about what you are capable of. Depending upon your specific strengths and weaknesses, FTP-based workouts might be too easy or too difficult, making them ineffective. Because it looks at your power across the full spectrum of efforts, 4DP™ is far superior to FTP-based workouts.  4DP allows The Sufferfest app to map every interval to the appropriate metric and at the right intensity. That means you’ll get the precise training load you need to get faster and without wasting a single pedal stroke.

Here's one more way to think of it: You wouldn't ask a tailor to make a suit for you based only on your height. So why would you want a workout based just on your FTP?

Q: How are my workouts going to change using 4DP™?

Depending upon your rider type, your particular strengths and weaknesses, and the workout you’re doing you might notice significant changes in your targets or more subtle differences. Conventional FTP-based workouts use a simple formula to calculate targets based on percentage of your FTP. For example, VO2 intervals might be set at 110% of your FTP, while sprint intervals might be set at 200% of your FTP. To give you the most effective workout possible, 4DP™ uses a different reference metric for each type of interval. Depending on where they are placed in a workout, short sprints may be mapped to your 5-second power (NM), while VO2 intervals may be mapped to your 5-minute power (MAP). If you’re a sprinter with an NM of 400% of your FTP, sprint workouts like Violator or The Shovel will feel very different as a 4DP™-optimized session. Your targets during the sprints will be higher, but ultimately more effective. If you’re doing an FTP or “sweet spot” workout you likely won’t notice much of a difference.

Q: Do I need to know anything about sports science to make this work?

No. We've done all the science for you. You just need to do the fitness test, Full Frontal, and then the app will do everything else for you to best optimise your workouts.

Q: What are rider types?

4DP™ uses your complete power profile to identify which of six rider types best describes you: Sprinter, Attacker, Pursuiter, Time Triallist, Climber, or Rouleur. Your rider type reflects your specific, innate strengths and helps identify what kind of workouts you need to focus on to become a more complete, well-rounded cyclist. It's important to note that your rider type isn't an indication of how strong you are - rather it's a representation of your innate characteristics. For more information on rider types, check out this article.

Q: How is my rider type determined?

A: The app uses an algorithm to analyze your results from Full Frontal, taking into account the absolute values, your gender, the weight you entered in your settings, as well as the specific relationships between your Neuromuscular Power, Maximal Aerobic Power, Functional Threshold Power, and Anaerobic Capacity. You could have the same FTP as another cyclist but be assigned a completely different rider type based upon these other factors.

Q: How do I start training with 4DP™? Is there any special equipment required?

If you’re already training with power (or Virtual Watts within The Sufferfest app, you’re ready to start training with 4DP™. You just need to complete the Full Frontal fitness test in the app. You’ll need, 1) a trainer and 2) some way to measure power and transmit that power data to The Sufferfest app. That means either a conventional “dumb” trainer and a power meter, a compatible smart trainer, or a conventional trainer with an ANT+ or Bluetooth speed sensor configured for Virtual Watts. Need information about Virtual Watts? Check out our the Virtual Watts section in our Help Centre.  

Q: What is Full Frontal? How is the workout different from your old Rubber Glove fitness test?

Short answer? Rubber Glove is one pointy stick, Full Frontal is four pointy sticks. Rubber Glove is a classic fitness test designed to measure only your Functional Threshold Power. FTP is defined as the maximum power you can sustain for an hour-long, all-out effort and is derived by taking the average power from a 20-minute maximum effort and subtracting 5%.  Full Frontal, on the other hand, is a comprehensive fitness assessment that measures not just FTP, but the four key ways cyclists produce power: Neuromuscular Power (sprint / 5-second power), Maximal Aerobic Power (VO2 / 5-minute power), Threshold Power (endurance / 20-minute power), and Anaerobic Capacity (one-minute power). It’s based on the same test Neal Henderson at APEX Coaching developed to gain critical insight into the fitness of the professional and elite athletes he trains. So, over the course of an hour, you'll get a thorough warm-up and then be taken through a specific sequence of four different tests. The Sufferfest app then analyses your results (based on the methods used by APEX Coaching) and generates your complete 4DP™ profile, assigns you a rider type, and personalizse the power targets in all of your workouts.

For more information on how to get the most out of your Full Frontal ride, read this and watch this:

Q: I finished Full Frontal and got a message that one or more of my values was automatically adjusted. Why is that?

The app uses well-documented ranges in human performance and physiological norms to validate your results from Full Frontal.  For example, it’s physiologically impossible for someone to have a Maximal Aerobic Power that is less than 115% of their Functional Threshold Power, regardless of their fitness. If any of your four test results fall outside the normal range of variation for that value (either higher or lower), the app will alert you and automatically adjust your test results to a valid number. Reasons for an invalid result may include improper pacing or inconsistent power reporting. Pacing a fitness test like Full Frontal takes practice. If you’re concerned about your results, review the pacing strategies video and try Full Frontal again once you’re properly recovered.

Q: My FTP from Full Frontal is lower than from other FTP tests. What’s going on?

First, let’s get this out of the way: you are not your FTP.  Threshold power is only one way you put out power on the bike. It only tells you how well you can generate power for long, steady-state efforts. Once your power goes north of your FTP, all bets are off.

Now, bear with us: here comes the science. After testing hundreds of athletes in his lab at the Boulder Center for Sports Medicine, Coach Neal Henderson found that for many athletes, their lab-determined FTP did not match up to the traditional 20-minute field test.  The assumption had been (and continues to be with conventional FTP tests)  that 95% of an athlete's 20-minute power is equal to their FTP. Unfortunately, it’s not that cut-and-dried. Two athletes can have the exact same 20-minute power, but produce that power differently. One may produce 97% of it aerobically, while the other may produce 93% of that power aerobically.  Assuming 95% of an athlete’s 20-minute equals their threshold power is the same as assuming everyone who is the same height has the same inseam.   Not only does this make the 20-minute power test imprecise, it also misses out on other important aspects of a rider’s physiology.

If you are a rider who is only producing 93% of your power during a 20-minute test aerobically, then that means you are drawing on other energy systems—either Maximal Aerobic Power (MAP) or Anaerobic Capacity (AC)— to generate that power. Instead of measuring your threshold power, the 20-minute test is really measuring multiple energy sources. That results in an FTP that is artificially high.  By measuring four distinct ways cyclists produce power, Full Frontal will be able to tell us where that additional power is coming from. A rider who is only generating 93% of their power over 20 minutes aerobically will often have 5-minute power (MAP) or 1-minute power (AC) that is well above average . Since the 20-minute test in Full Frontal comes after both the 5-second sprint efforts and the 5-minute test, you will not be able to hold the same 20-minute power in Full Frontal that you would in a conventional 20-minute test like Rubber Glove. Because of this, your FTP from Full Frontal is based on the full average of your 20-minute effort, rather than 95%. But to be accurate, you have to go all-out on the 5-minute effort that precedes it.

While this might tempt some people to go easy in the 5-minute effort to save something for the 20-minute effort, you need to keep in mind that the 4DP™ power targets for workouts are based on all 4 metrics (and the relationship between them), not just FTP.  If you sell yourself short in one area of the test to improve another area, the training you do afterwards won’t be accurately tailored to your true abilities, and you will miss out on the real fitness improvements you are looking for!

Lastly, it’s important to remember that training is a means to an end. You train and suffer today so you can be faster tomorrow. Fixating on a single number at a single point in time isn’t productive. What point is there in having an artificially-inflated FTP if you’re not getting the right training stimulus out of a session? Since 4DP™ takes all four metrics into account and personalizes all of your targets, you are ultimately going to get a much more effective workout, even with a “lower” FTP.

Q: Can I manually enter or adjust my 4DP™ values?

Technically, yes. But unless you have an advanced degree in Sports Physiology, we don’t recommend it. It’s not just the individual values that are important but the relationship between them. Here are the rules for when and how to adjust manually or to ride Full Frontal again.

Q: My 4DP™ values are different from the Badass Power Records in my passport. Why?

A: The Badass Power Records in your passport show your all-time highest power values for a given type of effort. The context in which you hit those numbers was likely very different from where those efforts occur in Full Frontal. The first 1-minute interval in Revolver is going to feel much easier than the final 1-minute effort at the end of Full Frontal. The sequence of the efforts in Full Frontal is as important as the type of effort that is being measured. As a result, you will most likely see power bests from other workouts that are higher than your results from Full Frontal.

Q: How often should I do Full Frontal?

Most APEX athletes will complete Full Frontal once every 3-4 months. Three months is enough time for you to make significant fitness gains, at which point training zones will need to be adjusted to ensure you are getting the right intensity for each workout.  Given how difficult Full Frontal is compared to other fitness tests, you should only attempt it on fresh, well-rested legs.  This means you need at least seven days of reduced training before exposing yourself to Full Frontal.  If you try and test more often than once every 3 months, you will either lose out on your normally-scheduled training week trying to be fresh, or you won’t be well-rested enough to get accurate results. The 'Training Plans' section of The Sufferfest app has a 7 day plan to prepare you for your best Full Frontal result.

Q: Does this change the Sufferfest training plans?

You can continue to the use the plans available as part of your App subscription to even better effect now that 4DP is here. While a personal coach can look at your training files to determine your weaknesses and adjust your training, generic training plans are not capable of making those fine adjustments.  You might have two riders, both with an FTP of 200W training for their first criterium.  That used to mean these two riders would get the exact same training plan. However, if one rider has a weakness of sprinting and one has a weakness of repeated efforts, each should be focusing on different kinds of workouts. The comprehensive rider profiling Full Frontal provides means we can adjust every plan to accommodate your strengths and weaknesses.  Every training plan has a goal you are working towards, and each goal has different physiological requirements.  With Full Frontal, we now have a much better picture of your physiology and can adjust the plans accordingly to make sure you are targeting the areas you need to in order to achieve your goals.

Q: This seems like the most awesome thing to happen to indoor training, ever. Am I right?


Check Out These Other Articles on 4DP™

How to Get the Most Out of Full Frontal

Learn More About Your Four-Dimensional Power™ Profile

Learn More About Strengths, Weaknesses and Recommended Workouts 

Learn More About Rider Types


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