Overreaching and overtraining

What it is

The European College of Sport Science and the American College of Sports Medicine describe a spectrum:

• Functional overreaching: a short-term dip in performance after a hard block, which leads to improvement once you recover. This is often planned.
• Non-functional overreaching (NFOR): the dip lasts longer and recovery doesn’t bring a performance gain, because training and recovery have been out of balance.
• Overtraining syndrome (OTS): a prolonged maladaptation, with fatigue, falling performance and mood disturbance that rest doesn’t quickly fix.

NFOR and OTS are hard to tell apart. The distinction depends on how things turn out, and on ruling out other causes such as illness, low energy intake or iron deficiency.

Why it matters for training decisions

Hard training is supposed to make you tired. The goal is to catch the point where tiredness stops turning into fitness. Early warning signs worth tracking together include sessions feeling harder at the same pace or power, worse sleep, low mood or motivation, and frequent minor illness.

How wearables measure it, and the limits

No wearable can diagnose overtraining. The consensus statement notes that none of the markers studied (hormones, performance tests, questionnaires, blood and immune markers) meets all the criteria to be generally accepted. HRV can fall, stay flat or even rise during overreaching, so a “normal” HRV doesn’t rule it out. If you think you’re overtrained, or you feel unwell, see a doctor.

How P247 uses it

P247 doesn’t diagnose overtraining. The weekly report looks at whether your training load rose faster than your recovery signals, and suggests what to change next week.

This glossary is general information to help you understand your training data. It isn't medical advice, diagnosis or treatment. For injury, illness, medication, blood test results or any health concern, speak to a qualified health professional.

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