FTP Testing: When to Use ERG Mode On or Off for Optimal Results

Should FTP test ERG be on or off?

Choosing whether to use ERG mode during an FTP test depends largely on your testing goals, experience level, and the specific aspects of your cycling performance you wish to evaluate.

Introduction to FTP Testing

Functional Threshold Power (FTP) is a cornerstone metric in cycling, representing the highest power output a rider can maintain in a quasi-steady state without fatiguing for approximately 60 minutes. It's a critical indicator of aerobic fitness and endurance performance, widely used to set training zones and track progress.

• What is FTP? While often defined as the power you can sustain for an hour, FTP is typically estimated through shorter, maximal efforts, most commonly a 20-minute test. The average power from this 20-minute effort is then multiplied by 0.95 to estimate your FTP.
• Why Test FTP? Regular FTP testing allows athletes and coaches to:
  • Establish personalized training zones (e.g., Z1-Z7) for effective structured workouts.
  • Track physiological adaptations and fitness improvements over time.
  • Measure the effectiveness of a training program.
  • Provide a benchmark for race pacing strategies.

Understanding ERG Mode

ERG mode is a feature found on smart trainers that automatically adjusts the resistance to hold you at a specific power output, regardless of your cadence. If your power drops, the trainer increases resistance; if it rises, resistance decreases.

• How ERG Mode Works: When enabled, you set a target power, and the trainer's resistance unit actively maintains that power. Your job is simply to keep pedaling. This is incredibly useful for structured interval training, ensuring you hit precise power targets without constant manual adjustment.
• Advantages of ERG Mode for Training: For daily workouts, ERG mode simplifies execution by removing the need for gear changes and constant attention to your power meter. It allows you to focus purely on maintaining cadence and form, ensuring you complete intervals exactly as prescribed.

ERG Mode ON for FTP Testing: Pros and Cons

Using ERG mode during an FTP test offers a highly controlled environment but also presents certain limitations.

Pros of ERG Mode ON:

• Consistent Power Output: The trainer precisely maintains your target power, removing the variability that can occur with manual pacing.
• Reduced Mental Load: You don't need to constantly monitor your power meter or make gear adjustments, allowing you to focus solely on sustained effort.
• Ideal for Beginners: Newer riders or those less experienced with pacing maximal efforts may find ERG mode helpful in ensuring they hit a consistent, challenging power target.
• Focus on Physiological Limit: It isolates the physiological ability to produce power, removing the variable of pacing strategy.

Cons of ERG Mode ON:

• Masks Pacing Ability: A crucial aspect of any maximal effort is pacing. ERG mode removes the need for this, meaning it doesn't assess your ability to distribute energy effectively.
• "Spiral of Death": If your cadence drops significantly due to fatigue, ERG mode will drastically increase resistance to maintain the target power. This can make it incredibly difficult to recover, often leading to a premature end of the test.
• Doesn't Replicate Real-World Riding: Outdoor riding, and even indoor riding in SIM or resistance mode, requires constant power management, gear changes, and adapting to terrain. ERG mode abstracts this.
• Less Responsive to Rider Feel: Some riders prefer to adjust their effort based on how they feel, slightly increasing or decreasing power as needed. ERG mode removes this flexibility.

ERG Mode OFF for FTP Testing: Pros and Cons

Testing with ERG mode off, typically in resistance or slope mode (where the trainer acts like a constant resistance or gradient), requires more active rider input.

Pros of ERG Mode OFF:

• Mimics Real-World Pacing: This mode forces you to actively manage your power output, cadence, and gear selection, closely simulating the demands of outdoor riding or racing.
• Tests Pacing Ability: It's a more comprehensive assessment of your cycling fitness, including your ability to pace a maximal effort effectively over time.
• Allows for Adjustments: You have full control to increase or decrease your effort based on how you feel, responding to fatigue or surges.
• Develops Rider Feel: Regularly testing in this mode helps you develop a better sense of sustainable effort levels without relying solely on the power meter.

Cons of ERG Mode OFF:

• Requires More Rider Skill/Focus: Maintaining a consistent, maximal power output for 20 minutes requires significant concentration and experience with pacing.
• Potential for Inconsistent Power Output: Without the trainer enforcing a set power, your average power might fluctuate more, potentially leading to a less "clean" test result if pacing is poor.
• Easier to Underperform: If you pace too conservatively or go out too hard and blow up, the test may not accurately reflect your true physiological limit.

When to Choose Which Mode

The optimal choice depends on your specific objectives:

• Choose ERG ON if:

  • You are new to FTP testing and want to eliminate pacing as a variable.
  • Your primary goal is to isolate your raw physiological power output in a highly controlled setting.
  • You want to focus purely on sustained effort without the mental load of power management.
  • You are performing a ramp test, where ERG mode is almost universally used to control the increasing power steps.

• Choose ERG OFF if:

  • You are an experienced rider comfortable with pacing maximal efforts.
  • You want to practice and assess your pacing strategy for race scenarios.
  • You prefer a testing environment that more closely mimics outdoor riding conditions.
  • You want a more comprehensive assessment that includes your ability to manage power over time.
  • You find the "spiral of death" in ERG mode too detrimental to your performance.

Best Practices for FTP Testing (Regardless of Mode)

Regardless of your ERG mode choice, adherence to a consistent protocol is paramount for accurate and comparable results.

• Proper Warm-up: A structured warm-up, typically including a few short, high-intensity efforts, prepares your body for the maximal test.
• Consistent Protocol: Use the same test protocol (e.g., 20-minute test), warm-up, cool-down, and recovery time between tests.
• Recovery: Ensure you are well-rested and fueled before the test. Avoid heavy training in the 24-48 hours prior.
• Repeatability: Conduct tests under similar conditions (same time of day, same equipment, same environment) to ensure results are comparable.
• Mental Preparation: A maximal effort test is physically and mentally demanding. Be prepared to push your limits.

Conclusion: Making an Informed Choice

There is no universally "correct" answer to whether ERG mode should be on or off for an FTP test. Both approaches offer valid ways to measure your fitness, each with distinct advantages and disadvantages. For a pure physiological assessment in a controlled environment, ERG mode can be effective. However, for a more comprehensive evaluation that includes crucial pacing skills relevant to real-world cycling, ERG mode off is often preferred by experienced athletes. Ultimately, the best method is the one you can execute consistently and that aligns with your individual training and performance goals.