Race-specific training

A runner recovering after adding training load
A runner recovering after adding training load

𝐑𝐚𝐜𝐞-𝐒𝐩𝐞𝐜𝐢𝐟𝐢𝐜 𝐓𝐫𝐚𝐢𝐧𝐢𝐧𝐠

Training Load Balance, based on your Training Load Scores, includes both intensity and duration but it doesn’t provide any insight into the distribution of running intensities in your training.

A longer run at a lower intensity can produce the same Training Load Score as a shorter run at a higher intensity.

Yet intensity is important, as the adaptations from higher intensities may be quite different than those from lower intensities.

And you may want to match those adaptations to your goal race – training for a marathon may have a different mix of intensities than training for a 5k.

𝐓𝐫𝐚𝐢𝐧𝐢𝐧𝐠 𝐈𝐧𝐭𝐞𝐧𝐬𝐢𝐭𝐲 𝐃𝐢𝐬𝐭𝐫𝐢𝐛𝐮𝐭𝐢𝐨𝐧 (𝐓𝐈𝐃)

A TID chart groups your time spent at each intensity into 3 or more groups, then displays the result as a stacked bar chart, with each stacked bar representing a week of training.

When Running with Power, the groups are typically ranges based on percentages of your Threshold Power. This ensures that when your Threshold Power changes, your adjusted intensities are still relative to what you’re capable of (and it means you don’t need to adjust the chart).

You can produce the chart for completed workouts to check the mix that you ran. Or you can produce the chart for planned workouts, to adjust the mix you’re planning to run, using planned Training Load Scores).

The TID chart is the third key metric for monitoring your training (along with Training Load Balance and Ramp Rate).

𝑺𝒉𝒐𝒖𝒍𝒅𝒏’𝒕 𝒚𝒐𝒖 𝒃𝒆 𝑹𝒖𝒏𝒏𝒊𝒏𝒈 𝒘𝒊𝒕𝒉 𝑷𝒐𝒘𝒆𝒓?

Questions?
📖 Getting Started

𝐓𝐨𝐩𝐢𝐜: 𝐓𝐫𝐚𝐢𝐧𝐢𝐧𝐠 𝐋𝐨𝐚𝐝
What is Training Load?
Training Load – a two-sided coin!
Achieving a Training Load Balance
The danger of ramping up too quickly
Race-specific training

The danger of ramping up too quickly

A runner recovering after adding training load
A runner recovering after adding training load

𝐓𝐡𝐞 𝐝𝐚𝐧𝐠𝐞𝐫 𝐨𝐟 𝐫𝐚𝐦𝐩𝐢𝐧𝐠 𝐮𝐩 𝐭𝐨𝐨 𝐪𝐮𝐢𝐜𝐤𝐥𝐲

Training loads your body, encouraging it to adapt.

But it’s a balance. Load the body too little, and it will not adapt; load it too much or too quickly, and it will break down instead of adapting; load your body correctly, and sustained long-term improvements are possible.

And the training loads are cumulative – as you continue to train, you continue to encourage adaptations.

Your training load is the sum of these cumulative stresses. Monitoring your training load helps ensure your training is productive, and that you minimise injury risk.

𝐓𝐫𝐚𝐢𝐧𝐢𝐧𝐠 𝐋𝐨𝐚𝐝 𝐦𝐞𝐭𝐫𝐢𝐜𝐬

Your Training Load Balance indicates whether your training is productive, with a negative (but not too negative) score indicating productive training.

Your Ramp Rate shows if you may be adding training load too quickly, replacing ‘the 10% rule’ with a metric based on your training volume and intensity.

𝐑𝐚𝐦𝐩 𝐑𝐚𝐭𝐞

Ramp Rate is the week-on-week difference in your Chronic Training Load (CTL) or your 42-day weighted average, depending on which set of metrics you’re using.

Why week-on-week? Because Long Runs will tend to impact your training load more than shorter interval sessions or easy/recovery runs.

Using a week-on-week calculation will ‘smooth out’ any fluctuations caused by your workout mix while still producing a useful metric.

𝐖𝐡𝐚𝐭’𝐬 𝐚 𝐠𝐨𝐨𝐝 𝐑𝐚𝐦𝐩 𝐑𝐚𝐭𝐞 𝐭𝐚𝐫𝐠𝐞𝐭?

It depends.

Runners that have been running for more years and that are less injury-prone may be able to cope with a ramp rate of 2 – 3 or higher.

New runners or those that are more injury-prone might find a ramp rate of 0.5 – 2 safer and more sustainable.

𝑺𝒉𝒐𝒖𝒍𝒅𝒏’𝒕 𝒚𝒐𝒖 𝒃𝒆 𝑹𝒖𝒏𝒏𝒊𝒏𝒈 𝒘𝒊𝒕𝒉 𝑷𝒐𝒘𝒆𝒓?

Questions?
📖 Getting Started

For more about Ramp Rate, see CTL Ramp Rate for Runners in the Facebook group Palladino Power Project.

𝐓𝐨𝐩𝐢𝐜: 𝐓𝐫𝐚𝐢𝐧𝐢𝐧𝐠 𝐋𝐨𝐚𝐝
What is Training Load?
Training Load – a two-sided coin!
Achieving a Training Load Balance
The danger of ramping up too quickly
Race-specific training

Achieving a Training Load Balance

A runner recovering after adding training load
A runner recovering after adding training load

𝐀𝐜𝐡𝐢𝐞𝐯𝐢𝐧𝐠 𝐚 𝐓𝐫𝐚𝐢𝐧𝐢𝐧𝐠 𝐋𝐨𝐚𝐝 𝐁𝐚𝐥𝐚𝐧𝐜𝐞

Training Load Scores, calculated for each workout, represent each workout’s metabolic stress.

You can use these scores to model the shorter-term and longer-term impacts from each workout.

Combining these, you can obtain a Training Load Balance (TLB), indicating whether your training is ‘productive’.

Training Load Balance at also known as Training Stress Balance (TSB) or Running Stress Balance (RSB) but the word ‘Stress’ may be confusing, implying mental stress rather than physical or metabolic stress. Load (rather than Stress) helps remove potential confusion, and is the term used by Steve Palladino in his article library.

Training Load Balance is also known as ‘form’ in heartrate-based models.

𝐏𝐫𝐨𝐝𝐮𝐜𝐭𝐢𝐯𝐞 𝐓𝐫𝐚𝐢𝐧𝐢𝐧𝐠

How does your TLB help ensure your training is productive?

Your TLB is the difference between the longer-term impacts and the shorter-term impacts (TLB = CTL – ATL):
🔹 A very positive balance indicates detraining or a lack of any meaningful training.
🔹 A positive balance may indicate tapering or a missed workout.
🔹 A negative balance indicates productive training – enough load to encourage adaptations, but not so much that there is a greater risk of injury or over-training.
🔹 A very negative balance may indicate over-training, with a greater risk of injury.

𝐇𝐨𝐰 𝐚𝐜𝐜𝐮𝐫𝐚𝐭𝐞 𝐢𝐬 𝐲𝐨𝐮𝐫 𝐓𝐫𝐚𝐢𝐧𝐢𝐧𝐠 𝐋𝐨𝐚𝐝 𝐁𝐚𝐥𝐚𝐧𝐜𝐞?

You can use your TLB to monitor your training, but be aware that:
🔹 You need 80+ days of workout data for your TLB to be accurate (because of the way the model works)
🔹 You should track your scores and compare them to how you actually feel to build your experience of what your TLB represents (for you)

Your Training Load Balance is a useful and straightforward way to monitor whether your training is productive.

𝑺𝒉𝒐𝒖𝒍𝒅𝒏’𝒕 𝒚𝒐𝒖 𝒃𝒆 𝑹𝒖𝒏𝒏𝒊𝒏𝒈 𝒘𝒊𝒕𝒉 𝑷𝒐𝒘𝒆𝒓?

Questions?
📖 Getting Started

For more information on Training Load Balance, see:
🔹 Running Training Load Metrics in the Palladino article library

𝐓𝐨𝐩𝐢𝐜: 𝐓𝐫𝐚𝐢𝐧𝐢𝐧𝐠 𝐋𝐨𝐚𝐝
What is Training Load?
Training Load – a two-sided coin!
Achieving a Training Load Balance
The danger of ramping up too quickly
Race-specific training

Training Load – a two-sided coin!

A runner recovering after adding training load
A runner recovering after adding training load

𝐓𝐫𝐚𝐢𝐧𝐢𝐧𝐠 𝐋𝐨𝐚𝐝 – 𝐚 𝐭𝐰𝐨-𝐬𝐢𝐝𝐞𝐝 𝐜𝐨𝐢𝐧!

On one side of the coin, the reason you’re training – improving your performance, your fitness, your speed, your ability to run further for longer.

On the other, the impact of your workouts – fatigue, muscle soreness, dehydration, injury risk … the list could go on.

How can a single Training Load Score (per workout) fully model training load – both the shorter-term impacts and the longer-term improvements?

𝐓𝐡𝐞 𝐑𝐞𝐬𝐞𝐚𝐫𝐜𝐡

Research into the impacts of training has resulted in various models:
✅ Rowbottom proposed a Stimulus, Fatigue, Recovery, Adaptation model, sometimes referred to as the supercompensation model
✅ Banister proposed an Impulse-Response model, popularised in the TRIMP metric based on Heart Rate measurements
✅ Allen, Coggan and McGregor adapted the Impulse-Response model for use with power, encapsulating it in the Performance Manager model.

𝐓𝐡𝐞 𝐏𝐞𝐫𝐟𝐨𝐫𝐦𝐚𝐧𝐜𝐞 𝐌𝐚𝐧𝐚𝐠𝐞𝐫 𝐦𝐨𝐝𝐞𝐥

The model has the following components:
1. A Training Load Score, which the model calls a Training Stress Score (TSS)
2. An Acute Training Load (ATL), modelling shorter-term impacts
3. A Chronic Training Load (CTL), modelling longer-term adaptations
4. A Training Load Balance, which the model calls a Training Stress Balance (TSB), representing the balance between ATL and CTL

The Performance Manager model uses 𝑦𝑜𝑢𝑟 Training Load Scores to calculate personal training metrics that indicate whether 𝑦𝑜𝑢𝑟 training is productive – not too much, not too little, just right for you.

And with the two different load metrics (ATL and CTL), the model includes both the shorter-term impacts and the longer-term improvements.

You may have encountered ATL and CTL already (without knowing it) – they have equivalents in other models:
🔹 ATL is known as ‘7d avg’ in Stryd’s model, and ‘fatigue’ in heartrate-based models
🔹 CTL is known as ’42d avg’ in Stryd’s model, and ‘fitness’ in heartrate-based models

𝑺𝒉𝒐𝒖𝒍𝒅𝒏’𝒕 𝒚𝒐𝒖 𝒃𝒆 𝑹𝒖𝒏𝒏𝒊𝒏𝒈 𝒘𝒊𝒕𝒉 𝑷𝒐𝒘𝒆𝒓?

Questions?
📖 Getting Started

For more information on the models, see:
🔹 Rowbottom, D.J., (2000), in Garrett, W.E., Kirkendall, D.T., (eds.). Periodization of Training. Philadelphia: Lippincott Williams & Wilkins.
🔹 Calvert, T.W., Banister, E.W., Savage, M.V., Bach, T., (1976) A Systems Model of the Effects of Training on Physical Performance
🔹 Allen, H., Coggan, A. & McGregor, S. (2019) Training+Racing with a Power Meter, 3rd Edition (pp. 158-160). Boulder: Velopress.
🔹 The Science of the TrainingPeaks Performance Manager on the TrainingPeaks website

𝐓𝐨𝐩𝐢𝐜: 𝐓𝐫𝐚𝐢𝐧𝐢𝐧𝐠 𝐋𝐨𝐚𝐝
What is Training Load?
Training Load – a two-sided coin!
Achieving a Training Load Balance
The danger of ramping up too quickly
Race-specific training

What is training load?

A runner recovering after adding training load

𝐖𝐡𝐚𝐭 𝐢𝐬 𝐭𝐫𝐚𝐢𝐧𝐢𝐧𝐠 𝐥𝐨𝐚𝐝?

When you train, you don’t go out for a run then wait until you’ve fully recovered before going out for another – it’s not a “one run at a time” thing.

Instead, you run three or more times each week (at the highest levels, perhaps running up to ten times a week). And while there will be recovery days included, mostly you’ll be running while still tired from the previous runs.

Training Load? It’s the cumulative load from your training workouts.

It’s easy to overdo it, leading to injury and time spent recovering (rather than training).

But if you’re training for an event, regular (and repeated) workouts are a necessity.

It’s a balance. Load your body too little, and it will not adapt; load it too much or too quickly, and it will break down instead of adapting; load your body correctly, and sustained long-term improvements are possible.

𝐓𝐫𝐚𝐢𝐧𝐢𝐧𝐠 𝐋𝐨𝐚𝐝 𝐒𝐜𝐨𝐫𝐞𝐬

Want to know the impact of your workout? Calculate its Training Load Score.

Training Load Scores combine ‘how hard?’ and ‘how long?’

They represent the workout’s metabolic stress – its impact on your body from the workout intensities and durations.

Training Load Scores are also known as Training Stress Scores (TSS) or Running Stress Scores (RSS) but the word ‘Stress’ may be confusing, implying mental stress rather than physical or metabolic stress. Load (rather than Stress) helps remove potential confusion, and is the term used by Steve Palladino in his article library.

𝐓𝐫𝐚𝐢𝐧𝐢𝐧𝐠 𝐋𝐨𝐚𝐝 𝐒𝐜𝐨𝐫𝐞𝐬 𝐚𝐫𝐞 𝐫𝐞𝐥𝐚𝐭𝐢𝐯𝐞 𝐭𝐨 𝐲𝐨𝐮𝐫 𝐓𝐡𝐫𝐞𝐬𝐡𝐨𝐥𝐝 𝐏𝐨𝐰𝐞𝐫

A one-hour run at Threshold Power produces a score of 100.

Why?

Scoring relative to your Threshold Power means Training Load Scores:
✅ match improvements in your fitness. As you become fitter, you can run the same workouts with less additional load; or you can handle harder workouts for the same additional load.
✅ match individual capabilities. If our thresholds are different and we run a workout together, your training load score for the workout will differ from my training load score for the same workout, reflecting our individual capabilities.

Counter-intuitively, if your fitness improves, and you run the same workout as earlier in your training, you’ll run it at a higher intensity, but end up with the same Training Load Score.

In numbers, if your Threshold power has improved from 250 Watts to 270 Watts, and you run a workout with 16-minute intervals at 94-96% of Threshold power, you’ll run the intervals at 235-240 Watts initially, repeating the workout at 258-264 Watts later in your training (higher intensity) but end up with a Training Load Score of 80 for both runs – your fitness has improved, you can handle the harder workout, but the impact of your workout is the same (in relative terms).

Training Load Scores are the foundation for metrics you can use to monitor your training load.

𝑺𝒉𝒐𝒖𝒍𝒅𝒏’𝒕 𝒚𝒐𝒖 𝒃𝒆 𝑹𝒖𝒏𝒏𝒊𝒏𝒈 𝒘𝒊𝒕𝒉 𝑷𝒐𝒘𝒆𝒓?

Questions?
📖 Getting Started

For more information on Training Load Scores, see:
🔹 What is TSS? on the TrainingPeaks website
🔹 Running Stress Score (RSS) on the Stryd website
🔹 Running Training Load Metrics in the Palladino article library

𝐓𝐨𝐩𝐢𝐜: 𝐓𝐫𝐚𝐢𝐧𝐢𝐧𝐠 𝐋𝐨𝐚𝐝
What is Training Load?
Training Load – a two-sided coin!
Achieving a Training Load Balance
The danger of ramping up too quickly
Race-specific training

Is my PDC accurate?

A Power-Duration Curve (with accompanying Mean-Max Power curve)
A Power-Duration Curve (with accompanying Mean-Max Power curve)

𝐈𝐬 𝐦𝐲 𝐏𝐃𝐂 𝐚𝐜𝐜𝐮𝐫𝐚𝐭𝐞?

Your PDC is modelled using your best efforts from your recent workouts – usually, the last 90 days of workouts.

Its accuracy (and its usefulness) depends on whether those best efforts include some maximum effort runs for a range of different durations.

𝐁𝐞𝐬𝐭 𝐄𝐟𝐟𝐨𝐫𝐭𝐬?

Best efforts are those efforts with the highest average power for each duration on your PDC.

They need not be the best you could have achieved, just the best that you actually ran during the last 90 days.

𝐌𝐚𝐱𝐢𝐦𝐮𝐦 𝐄𝐟𝐟𝐨𝐫𝐭𝐬?

Maximum efforts are efforts where you deliberately run as hard as you can for each duration.

They represent the best you can currently achieve.

𝐀 𝐫𝐚𝐧𝐠𝐞 𝐨𝐟 𝐝𝐢𝐟𝐟𝐞𝐫𝐞𝐧𝐭 𝐝𝐮𝐫𝐚𝐭𝐢𝐨𝐧𝐬?

Your PDC reflects your capability over very short durations (20-30 seconds), short durations (2-3 minutes), medium durations (12-15 minutes) and longer durations (20-40 minutes).

𝐓𝐨 𝐞𝐧𝐬𝐮𝐫𝐞 𝐲𝐨𝐮𝐫 𝐏𝐃𝐂 𝐭𝐫𝐮𝐥𝐲 𝐫𝐞𝐟𝐥𝐞𝐜𝐭𝐬 𝐲𝐨𝐮𝐫 𝐜𝐚𝐩𝐚𝐛𝐢𝐥𝐢𝐭𝐲…

Your PDC needs to be ‘fresh’:
⚡ A PDC that may have been ‘accurate’ 60 days ago is not necessarily ‘accurate’ today
⚡ A PDC that includes best efforts rather than maximum efforts may not represent the best you can actually achieve

To ensure your PDC is ‘fresh’:
✅ your training should include maximum effort runs for each of the above durations, so that your last 90 days of workouts includes a maximum effort for each duration
✅ you should run maximum efforts every 4-6 weeks, alternating between durations, so that your Threshold Power (and your PDC) reflects your current capability.

𝑺𝒉𝒐𝒖𝒍𝒅𝒏’𝒕 𝒚𝒐𝒖 𝒃𝒆 𝑹𝒖𝒏𝒏𝒊𝒏𝒈 𝒘𝒊𝒕𝒉 𝑷𝒐𝒘𝒆𝒓?

Questions?
📖 Getting Started

𝐓𝐨𝐩𝐢𝐜: 𝐏𝐨𝐰𝐞𝐫-𝐃𝐮𝐫𝐚𝐭𝐢𝐨𝐧 𝐂𝐮𝐫𝐯𝐞
What are you capable of?
You fatigue faster at higher intensities
You fatigue more slowly at lower intensities
How do I use my PDC?
Is my PDC accurate?

How do I use my PDC?

A Power-Duration Curve (with accompanying Mean-Max Power curve)
A Power-Duration Curve (with accompanying Mean-Max Power curve)

𝐇𝐨𝐰 𝐝𝐨 𝐈 𝐮𝐬𝐞 𝐦𝐲 𝐏𝐃𝐂?

Your PDC is individual to you, your fitness, and your abilities.

It changes as you train (or detrain).

If you’re training for an event, it should move up (higher power for same duration), to the right (longer duration for same power), or both.

𝐖𝐡𝐚𝐭 𝐝𝐨𝐞𝐬 𝐭𝐡𝐢𝐬 𝐦𝐞𝐚𝐧?

You can use your PDC to:
✅ identify the power you should be able to maintain for every duration modelled on your PDC – your current capability
✅ estimate how well you might perform for a shorter event, where you’ll be running at an effort where the fast component dominates
✅ estimate how well you might perform for a longer event, where you’ll be running at an effort where the slow component dominates
✅ estimate your threshold, although your PDC isn’t usually used for that. Your threshold lies approximately where the two curves meet – the vertical blue line in the image

𝐇𝐨𝐰 𝐝𝐨 𝐈 𝐤𝐧𝐨𝐰 𝐢𝐟 𝐦𝐲 𝐏𝐃𝐂 𝐢𝐬 𝐚𝐜𝐜𝐮𝐫𝐚𝐭𝐞?

A good question, and one that’s the topic of the final post in this series.

𝑺𝒉𝒐𝒖𝒍𝒅𝒏’𝒕 𝒚𝒐𝒖 𝒃𝒆 𝑹𝒖𝒏𝒏𝒊𝒏𝒈 𝒘𝒊𝒕𝒉 𝑷𝒐𝒘𝒆𝒓?

Questions?
📖 Getting Started

𝐓𝐨𝐩𝐢𝐜: 𝐏𝐨𝐰𝐞𝐫-𝐃𝐮𝐫𝐚𝐭𝐢𝐨𝐧 𝐂𝐮𝐫𝐯𝐞
What are you capable of?
You fatigue faster at higher intensities
You fatigue more slowly at lower intensities
How do I use my PDC?
Is my PDC accurate?

You fatigue more slowly at lower intensities

A Power-Duration Curve (with accompanying Mean-Max Power curve)
A Power-Duration Curve (with accompanying Mean-Max Power curve)

𝐘𝐨𝐮 𝐟𝐚𝐭𝐢𝐠𝐮𝐞 𝐦𝐨𝐫𝐞 𝐬𝐥𝐨𝐰𝐥𝐲 𝐚𝐭 𝐥𝐨𝐰𝐞𝐫 𝐢𝐧𝐭𝐞𝐧𝐬𝐢𝐭𝐢𝐞𝐬

Intuitively, this is obvious.

If you run easy, you can run for a longer time, and the easier you run, the longer you can keep running (within your personal limits).

What’s not obvious is that there is a mathematical relationship between your intensity (your effort) and how long you can hold it.

𝐓𝐡𝐞 𝐫𝐞𝐬𝐞𝐚𝐫𝐜𝐡

In 1977, Peter Riegel researched the relationship between runners’ performances over different distances and concluded that an exponential curve could predict race times for runners, given a performance at another distance – the slow component of fatigue follows an exponential curve.

Riegel expanded on his thesis in 1981, stating that his formula concerned “activities in the endurance range, lasting between 3-5 and 230 minutes.”

Riegel’s formula plots time versus distance. Work by Van Dijk and Van Megen in 2017 concluded that there’s a similar relationship between power and time.

The curve is always exponential but may be flatter, showing better fatigue resistance, or steeper, showing worse fatigue resistance for longer events.

The picture shows the slow element of fatigue as the right side of your Power-Duration Curve, starting from the dotted blue line and extending further right.

𝐖𝐡𝐲 𝐢𝐬 𝐭𝐡𝐢𝐬 𝐮𝐬𝐞𝐟𝐮𝐥?

Knowing the slope of your curve and the event distance, it’s possible to predict how well you might perform for a longer event (e.g. a Half-Marathon), where the slow component dominates.

A race power target that reflects your personal best!

𝑺𝒉𝒐𝒖𝒍𝒅𝒏’𝒕 𝒚𝒐𝒖 𝒃𝒆 𝑹𝒖𝒏𝒏𝒊𝒏𝒈 𝒘𝒊𝒕𝒉 𝑷𝒐𝒘𝒆𝒓?

Questions?
📖 Getting Started

For more information on the research, please see:
🔹 Riegel, P., (1981) Athletic Records and Human Endurance: A time vs. distance equation describing world-record performances may be used to compare the relative endurance capabilities of various groups of people.
🔹 Van Dijk, H. & Van Megen, R. (2017) The Secret of Running. Maidenhead: Meyer & Meyer Sport (UK) Ltd

𝐓𝐨𝐩𝐢𝐜: 𝐏𝐨𝐰𝐞𝐫-𝐃𝐮𝐫𝐚𝐭𝐢𝐨𝐧 𝐂𝐮𝐫𝐯𝐞
What are you capable of?
You fatigue faster at higher intensities
You fatigue more slowly at lower intensities
How do I use my PDC?
Is my PDC accurate?

You fatigue faster at higher intensities

A Power-Duration Curve (with accompanying Mean-Max Power curve)
A Power-Duration Curve (with accompanying Mean-Max Power curve)

𝐘𝐨𝐮 𝐟𝐚𝐭𝐢𝐠𝐮𝐞 𝐟𝐚𝐬𝐭𝐞𝐫 𝐚𝐭 𝐡𝐢𝐠𝐡𝐞𝐫 𝐢𝐧𝐭𝐞𝐧𝐬𝐢𝐭𝐢𝐞𝐬

Intuitively, this is obvious.

If you sprint, you can’t sprint for a long time, and the faster you sprint, the shorter the time you can keep sprinting.

What’s not obvious is that there is a mathematical relationship between your intensity (your effort) and how long you can hold it.

𝐓𝐡𝐞 𝐫𝐞𝐬𝐞𝐚𝐫𝐜𝐡

Monod and Scherrer’s research into single muscle groups showed that the fast component of fatigue follows a hyperbolic curve.

This research identified the bottom of the curve (the asymptote) as ‘an exercise intensity that could be sustained for a very long time’, naming it Critical Power (CP).

The research also identified that the curve’s hyperbolic shape makes it ‘possible to define the maximum amount of work that can be performed in a given time, as well as the conditions of work performed without fatigue.’

They called this maximum amount of work W’. Anaerobic Work Capacity (AWC) and Reserve Work Capacity (RWC) are other names for W’; Functional Reserve Capacity (FRC) describes a similar concept with a different calculation method (but still hyperbolic).

Further research by Hill extended and validated these concepts for whole-body exercise, noting that ‘for a very long time’ was usually 30 to 60 minutes of exercise at CP.

The picture shows the fast element of fatigue as the left side of your Power-Duration Curve, starting from the power axis and extending to the dotted blue line.

𝐖𝐡𝐲 𝐢𝐬 𝐭𝐡𝐢𝐬 𝐮𝐬𝐞𝐟𝐮𝐥?

Knowing the maximum amount of work you can perform and the event distance, you can calculate a race power target for a shorter event (e.g. a 5k), where the fast component dominates.

A race power target that reflects your personal best!

𝑺𝒉𝒐𝒖𝒍𝒅𝒏’𝒕 𝒚𝒐𝒖 𝒃𝒆 𝑹𝒖𝒏𝒏𝒊𝒏𝒈 𝒘𝒊𝒕𝒉 𝑷𝒐𝒘𝒆𝒓?

Questions?
📖 Getting Started

For more information on the research, please see:
🔹 Monod, H. & Scherrer, J., (2007) The Work Capacity of a Synergic Muscle Group
🔹 Hill, D., (2012) The Critical Power Concept

𝐓𝐨𝐩𝐢𝐜: 𝐏𝐨𝐰𝐞𝐫-𝐃𝐮𝐫𝐚𝐭𝐢𝐨𝐧 𝐂𝐮𝐫𝐯𝐞
What are you capable of?
You fatigue faster at higher intensities
You fatigue more slowly at lower intensities
How do I use my PDC?
Is my PDC accurate?

What are you capable of?

A Power-Duration Curve (with accompanying Mean-Max Power curve)
A Power-Duration Curve (with accompanying Mean-Max Power curve)

𝐖𝐡𝐚𝐭 𝐚𝐫𝐞 𝐲𝐨𝐮 𝐜𝐚𝐩𝐚𝐛𝐥𝐞 𝐨𝐟?

This is a subtle question, as the answer depends on:
❓ how hard you run – your effort
❓ how long you can sustain that effort
❓ how well you’re able to convert that effort into forward motion

Your Power-Duration Curve (PDC) can help answer the first two – the third depends on your Running Effectiveness.

𝐌𝐨𝐝𝐞𝐥𝐥𝐢𝐧𝐠 𝐲𝐨𝐮𝐫 𝐏𝐃𝐂

The higher your power (your effort), the shorter the duration you can sustain it; the lower your power, the longer you can sustain it.

In other words, there’s an inverse relationship between power and duration.

You can chart this relationship. The result is a chart showing your Mean-Max Power (MMP) – the best effort you can sustain for each duration (measured using average power for each) .

Based on your MMP, your PDC models your best efforts over a range of different durations, showing (for each) the effort you could sustain.

The picture shows a typical PDC (the orange line) based on a typical MMP (the red dotted line).

It’s usually charted using a duration scale that expands the left side of the curve and compresses the right side, revealing that the PDC is actually two separate curves.

𝐘𝐨𝐮𝐫 𝐏𝐃𝐂 𝐢𝐬 𝐫𝐞𝐚𝐥𝐥𝐲 𝐚 𝐟𝐚𝐭𝐢𝐠𝐮𝐞-𝐫𝐞𝐬𝐢𝐬𝐭𝐚𝐧𝐜𝐞 𝐜𝐮𝐫𝐯𝐞

How long you can sustain a particular effort level depends on how much you can do before tiring – it depends on how you fatigue.

Fatigue has two components: a fast component and a slow component.

Both elements of fatigue are always present, but the fast element of fatigue dominates at higher intensities, and the slow element dominates at lower intensities.

These are the two curves that, together, make up the PDC.

𝑺𝒉𝒐𝒖𝒍𝒅𝒏’𝒕 𝒚𝒐𝒖 𝒃𝒆 𝑹𝒖𝒏𝒏𝒊𝒏𝒈 𝒘𝒊𝒕𝒉 𝑷𝒐𝒘𝒆𝒓?

Questions?
📖 Getting Started

From its first introduction in ‘Training and Racing with a Power Meter’ (Allen, H., Coggan, A. & McGregor, S.) in 2006, and its subsequent incorporation into WKO4 in 2015, the PDC has become the standard for modelling your power over all time periods. For more information on the PDC as implemented in WKO, see ‘Scientific Basis of the New Power Duration Model in WKO4‘.

𝐓𝐨𝐩𝐢𝐜: 𝐏𝐨𝐰𝐞𝐫-𝐃𝐮𝐫𝐚𝐭𝐢𝐨𝐧 𝐂𝐮𝐫𝐯𝐞
What are you capable of?
You fatigue faster at higher intensities
You fatigue more slowly at lower intensities
How do I use my PDC?
Is my PDC accurate?