Tag: Physiology

𝐓𝐫𝐚𝐢𝐧𝐢𝐧𝐠 𝐒𝐭𝐫𝐞𝐬𝐬 – 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.

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

Can a single Stress Score be used to model both the shorter-term impacts and the longer-term improvements?

Note that ‘stress’ in this context refers to the physical (and physiological) effects of training, rather than stress from anxiety or worries.

𝐓𝐡𝐞 𝐑𝐞𝐬𝐞𝐚𝐫𝐜𝐡

Research into the effects of training stress 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 Stress Score (TSS)
2. A Chronic Training Load (CTL), modelling longer-term adaptations
3. An Acute Training Load (ATL), modelling shorter-term impacts
4. A Training Stress Balance, indicating whether your training is ‘productive’

The Performance Manager model uses 𝑦𝑜𝑢𝑟 Stress Scores (per workout) 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, the model includes both the shorter-term impacts and the longer-term improvements.

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

𝐇𝐨𝐰 𝐝𝐨 𝐲𝐨𝐮 𝐡𝐚𝐧𝐝𝐥𝐞 𝐭𝐫𝐚𝐢𝐧𝐢𝐧𝐠 𝐬𝐭𝐫𝐞𝐬𝐬?

Let’s face it, training is stressful.

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

But if you’re training for an event, a little stress is a necessity.

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

𝐒𝐭𝐫𝐞𝐬𝐬 𝐒𝐜𝐨𝐫𝐞𝐬

Want to know how stressful your workout was? Calculate its Stress Score.

Stress Scores combine ‘how hard?’ and ‘how long?’

They represent the workout’s metabolic stress – its impact on your body, NOT its impact on your mental health.

Which is an important point – ‘stress’ in the context of training relies on what you can measure, on the physical (and physiological) impacts, rather than stress in the form of anxiety or worries.

𝐒𝐭𝐫𝐞𝐬𝐬 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 Stress Scores:
✅ match improvements in your fitness. As you become fitter, you can run the same workouts with less relative stress; or you can handle harder workouts for the same relative stress. This means that as your Threshold Power improves, if you run the same workout (the same durations and the same percentages of Threshold Power), your Stress Score for the workout will remain unchanged – even though you ran the repeated workout at a higher power.
✅ match individual capabilities. If our thresholds are different and we run a workout together, your stress score for the workout will differ from my stress score for the same workout, reflecting our individual capabilities.

Stress Scores are the foundation for metrics you can use to monitor your training stress.

𝑺𝒉𝒐𝒖𝒍𝒅𝒏’𝒕 𝒚𝒐𝒖 𝒃𝒆 𝑹𝒖𝒏𝒏𝒊𝒏𝒈 𝒘𝒊𝒕𝒉 𝑷𝒐𝒘𝒆𝒓?

❓ Questions?
📖 Getting Started

For more information on Stress Scores, see:
🔹 What is TSS? on the TrainingPeaks website
🔹 Running Stress Score (RSS) on the Stryd website