What is FTP and Why Does It Matter?
Functional Threshold Power (FTP) is one of the most widely used metrics in cycling performance. It represents the maximum power a rider can sustain for approximately one hour before fatigue sets in. FTP is a cornerstone of structured training, race strategy, and performance tracking.
However, it is often misunderstood, and its significance is sometimes overstated.
This article will break down the physiological basis of FTP, its relationship with lactate threshold and endurance performance, and some of the most common misconceptions surrounding it.
The Physiological Basis of FTP
FTP is not a standalone physiological metric but a practical estimate of an athlete’s sustainable aerobic power. It is closely linked to two key physiological markers:
FTP is influenced by multiple physiological factors:
How FTP Relates to Lactate Threshold and Endurance Performance
Many cyclists mistakenly equate FTP with lactate threshold, but they are not identical. Here’s how they differ:
FTP plays a significant role in endurance performance because it determines how efficiently a cyclist can sustain high power outputs over long durations.
A higher FTP means:
However, FTP alone does not dictate success. A well-rounded cyclist must also develop anaerobic capacity, VO2 max, and fatigue resistance to perform well in races or long endurance events.
Common Misconceptions About FTP
1. FTP = One-Hour Power
While FTP is often referred to as the power you can hold for an hour, this is a simplification. Many riders struggle to sustain their FTP for a full 60 minutes due to factors like fatigue resistance, fueling, and psychological tolerance.
2. A Higher FTP Automatically Means Faster Racing
A rider with a higher FTP is not always the fastest. Race dynamics, tactical awareness, and anaerobic repeatability play huge roles. For example, a sprinter with a lower FTP but explosive power can still outperform a high-FTP time trialist in certain scenarios.
3. FTP is the Only Metric That Matters
FTP is a useful benchmark, but it does not capture the full picture of cycling performance. Metrics like W’ (anaerobic work capacity), VO2 max, and fatigue resistance provide deeper insights into strengths and weaknesses.
4. FTP Testing is Always Accurate
Most FTP tests (20-minute tests, ramp tests, etc.) estimate FTP rather than measuring it directly. External factors such as fatigue, motivation, and environmental conditions can all skew results. Lab-based lactate or gas exchange testing provides a more precise physiological profile.
Conclusion
FTP is a critical metric for cyclists, offering a practical way to measure and track endurance performance. However, it is not a perfect representation of lactate threshold, nor is it the only metric that matters for race success. Understanding its limitations and how it fits into a broader physiological profile allows cyclists to train more effectively and apply FTP insights intelligently.
In the next article, we’ll explore how to measure FTP, the best testing methods, and common pitfalls to avoid.
Functional Threshold Power (FTP) is one of the most widely used metrics in cycling performance. It represents the maximum power a rider can sustain for approximately one hour before fatigue sets in. FTP is a cornerstone of structured training, race strategy, and performance tracking.
However, it is often misunderstood, and its significance is sometimes overstated.
This article will break down the physiological basis of FTP, its relationship with lactate threshold and endurance performance, and some of the most common misconceptions surrounding it.
The Physiological Basis of FTP
FTP is not a standalone physiological metric but a practical estimate of an athlete’s sustainable aerobic power. It is closely linked to two key physiological markers:
- Lactate Threshold (LT2): The point at which lactate accumulation outpaces clearance, causing fatigue to set in rapidly. FTP is often considered a field-based estimate of LT2, but it is not an exact match.
- Maximal Aerobic Power (MAP): The highest power output a rider can sustain during a maximal ramp test. FTP typically sits at around 70-90% of MAP, depending on an athlete’s efficiency and fractional utilisation.
FTP is influenced by multiple physiological factors:
- Mitochondrial efficiency: The ability of muscle cells to produce ATP aerobically.
- Capillarisation: The density of small blood vessels supplying muscles with oxygen.
- Lactate clearance: How well the body shuttles and reuses lactate as fuel.
- Muscle fibre composition: The ratio of slow-twitch to fast-twitch fibres, affecting endurance capabilities.
How FTP Relates to Lactate Threshold and Endurance Performance
Many cyclists mistakenly equate FTP with lactate threshold, but they are not identical. Here’s how they differ:
- LT1 (Aerobic Threshold): The point at which blood lactate first starts to rise above baseline. Training below LT1 improves fat oxidation and endurance.
- LT2 (Anaerobic Threshold): The point where lactate accumulation becomes unsustainable. FTP is generally close to LT2 but slightly lower.
FTP plays a significant role in endurance performance because it determines how efficiently a cyclist can sustain high power outputs over long durations.
A higher FTP means:
- Better endurance: The ability to sustain higher intensities without accumulating excessive lactate.
- Improved race performance: Stronger pacing ability in time trials, breakaways, and climbing efforts.
- Higher repeatability: The ability to recover quickly between surges in a race.
However, FTP alone does not dictate success. A well-rounded cyclist must also develop anaerobic capacity, VO2 max, and fatigue resistance to perform well in races or long endurance events.
Common Misconceptions About FTP
1. FTP = One-Hour Power
While FTP is often referred to as the power you can hold for an hour, this is a simplification. Many riders struggle to sustain their FTP for a full 60 minutes due to factors like fatigue resistance, fueling, and psychological tolerance.
2. A Higher FTP Automatically Means Faster Racing
A rider with a higher FTP is not always the fastest. Race dynamics, tactical awareness, and anaerobic repeatability play huge roles. For example, a sprinter with a lower FTP but explosive power can still outperform a high-FTP time trialist in certain scenarios.
3. FTP is the Only Metric That Matters
FTP is a useful benchmark, but it does not capture the full picture of cycling performance. Metrics like W’ (anaerobic work capacity), VO2 max, and fatigue resistance provide deeper insights into strengths and weaknesses.
4. FTP Testing is Always Accurate
Most FTP tests (20-minute tests, ramp tests, etc.) estimate FTP rather than measuring it directly. External factors such as fatigue, motivation, and environmental conditions can all skew results. Lab-based lactate or gas exchange testing provides a more precise physiological profile.
Conclusion
FTP is a critical metric for cyclists, offering a practical way to measure and track endurance performance. However, it is not a perfect representation of lactate threshold, nor is it the only metric that matters for race success. Understanding its limitations and how it fits into a broader physiological profile allows cyclists to train more effectively and apply FTP insights intelligently.
In the next article, we’ll explore how to measure FTP, the best testing methods, and common pitfalls to avoid.
