The Sufferfest Announce Four-Dimensional Power (4DP™)

World Champ, Flora Duffy’s coach, Neal Henderson Partners with The Sufferest on Four-Dimensional Power

The Sufferfest, a comprehensive training app for cyclists and triathletes, today announced the launch of the Four-Dimensional Power (4DP)™ platform with the latest release of The Sufferfest Complete Training System. 4DP™ uses four key performance metrics to create a complete power profile for athletes, identify their rider type to help guide their training, and provide an unprecedented level of workout personalization.

Developed in partnership with Neal Henderson’s APEX Coaching and Consulting, 4DP™ represents a fundamental shift in the way athletes train indoors. Instead of relying on the single metric of Functional Threshold Power (FTP) to set power targets, 4DP™ uses FTP in conjunction with an athlete’s Neuromuscular Power (NM), Maximal Aerobic Power (MAP) and Anaerobic Capacity (AC). Every interval is optimized by The Sufferfest app to match an athlete’s unique profile, ensuring they get the precise training stimulus necessary to maximize fitness gains.

The below is via the Sufferfest web page:





Training apps that base power targets only on your FTP are just guessing at what you’re capable of above threshold. Not The Sufferfest. We use four key metrics—Neuromuscular Power, Anaerobic Capacity, Maximal Aerobic Power and Functional Threshold Power—to create your complete power profile. We then generate personalized power targets for all of your workouts, giving you exactly the training stimulus you need to get faster. Those other apps don’t know you like 4DP™ does.


Why is FTP, which only measures your aerobic power, an inadequate measure of your fitness? Because cycling isn’t just about long, sustained efforts. It’s about attacks, surges, sprints and breakaways. It’s about being able to recover and hit it again. That’s why our Four-Dimensional Power™ profile captures your performance across all four of your key energy systems:


Functional Threshold Power (FTP) has been *the* metric used by cyclists to set training zones and power targets. But FTP only measures aerobic capacity—your ability to put down power during long, sustained efforts.

FTP doesn’t tell you how well you can sprint, or deliver repeated attacks, or tackle short, steep climbs at maximum effort. FTP is a poor predictor of your ability to generate power above threshold. Training apps that only use FTP to set power targets are making assumptions about what you’re capable of, and what targets you need to hit to get faster.


Take two cyclists: Both have an FTP of 250 W. Other cycling apps will give both riders the same target for sprint efforts based on a simple percentage of their FTP, typically 180% or 450 W. What those apps don’t know is that Rider A has a maximum sprint power of 1,150 W, while Rider B has a maximum sprint power of 547 W. The result? Rider A will find that 450 W target far too easy—and fail to get any training benefit—while Rider B will find that target nearly impossible to hit and be unable to finish the workout. Consider the example below:



What makes training with Four-Dimensional Power™ so powerful is the unprecedented level of workout precision and personalization. The Sufferfest app will tailor the power targets in all of your workouts to match your unique 4DP™ profile. Different kinds of efforts will reference the appropriate metric, whether that’s Neuromuscular, Anaerobic, Maximal Aerobic, or Threshold Power. You’ll work at the exact intensity necessary to get stronger, faster, and more powerful, without wasting a single pedal stroke. Say goodbye to cookie cutter, FTP-based workouts that don’t know you. Say hello to effective, personalized 4DP™ workouts.



Not only does your 4DP™ profile tell us what you can do, it also tells us what kind of rider you are. 4DP™ will reveal your hidden power and assign you one of six Rider Types, allowing you to better focus your training:

We’ll also make specific workout recommendations to both develop your strengths and address your weaknesses. No other cycling training app can do that.


More than a year in the making, Four-Dimensional Power™ was developed in partnership with the sports scientists at APEX Coaching and Consulting in Boulder, Colorado. APEX has built a global reputation training the best of the best, including professional cyclists, Olympic triathletes, and multiple world champions. APEX founder Neal Henderson has known for years that FTP alone isn’t enough to design workouts that work. His research with hundreds of athletes both at APEX and at the Boulder Center for Sports Medicine showed that conventional FTP tests weren’t effective in predicting what an athlete was capable of, especially above threshold. To solve this shortcoming, he developed a comprehensive fitness assessment that gives a complete picture of how effectively an athlete produces power across a range of efforts.

We worked with Neal and APEX Senior Coach Mac Cassin to adapt the same fitness assessment they use with their athletes to create the Full Frontal fitness test. In addition to measuring the four key ways of producing power, Full Frontal also uses known variations in human performance to validate your results. We know whether you nailed the test, were holding back, or might have to do it again.

All of the workouts in The Sufferfest library were analyzed to map every interval to the appropriate 4DP™ metric. This wasn’t simply a matter of setting sprints to Neuromuscular Power or VO2 efforts to Maximal Aerobic Power, but involved looking at each effort’s duration, where it occurs in the workout, and what efforts follow it.

The result is the most sophisticated cycling training app in the world. Don’t guess with FTP – train with the precision of 4DP™.


With the release of Four-Dimension Power, The Sufferfest has taken the same comprehensive fitness testing and personalized power target mapping used by the pros and made it available to you. No other training app gives you this kind of individually-optimized training. No other app gives you sessions this effective. Stop wasting time on workouts that don’t work. Go beyond your threshold and take your fitness to a new dimension with Four-Dimensional Power™.




Jimmy Archer

Founder and Editor at Jimmy has been a professional athlete for over 18 years as a runner, cyclist, mountain biker, cross country skier, and primarily, triathlete. Jimmy has a degree in exercise science from the University of Colorado and is a USA Triathlon and USA Cycling certified coach. Jimmy became a freelance writer in 2000 while competing and covering the ITU Winter Triathlon World Championship. Since that time Jimmy has been head editor at two magazines, been published in numerous publications within the endurance sport, recreation, and travel segments. Currently Jimmy is competing professionally in off-road multisport. In his spare time Jimmy passionately follows Formula 1, Moto GP, and is an avid cook.

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