Identifying Overtraining Syndrome (OTS) and Planning a Return to Training

Introduction

A runner with a full-marathon PB goal in mind, aiming to break the 3:30 barrier, ramped up their monthly mileage from 150km to 250km in the final 3 months of preparation. Not only did their performance fail to improve, but a week before the race they felt exhausted, emotionally drained, and had lost all passion for running… This is a classic case of Overtraining Syndrome (OTS).

OTS is the most insidious and challenging of all training injuries because its “symptoms” are often misinterpreted by runners as “not trying hard enough,” leading them to increase the load further and sink deeper into the hole.

The Three Stages of Training Fatigue

Understanding the progression of training fatigue allows you to intervene before the problem worsens:

Diagnostic Criteria for OTS

OTS is a diagnosis of exclusion; before confirming it, other conditions that could cause similar symptoms (thyroid dysfunction, anemia, diabetes, depression, etc.) must be ruled out.

Primary Symptoms

Performance-related:

• At the same intensity, heart rate is 5–10bpm higher than usual (sympathetic OTS) or lower than normal (parasympathetic OTS)
• Previously easy paces now feel extremely effortful
• Noticeable decline in strength and power
• Prolonged recovery time (muscle soreness persists beyond 72 hours)

Systemic symptoms:

• Persistent fatigue that does not improve with rest
• Worsened sleep quality (difficulty falling asleep or not feeling rested)
• Mood swings, irritability, anxiety, or low mood
• Reduced immunity (recurrent colds, minor infections)
• Changes in appetite (usually decreased)
• Irregular menstruation may occur in women

Quantitative Assessment Tools

1. Resting heart rate monitoring: Measure resting heart rate every morning before getting out of bed. If it is 5–7bpm above the average for 3 consecutive days, reduce training volume
2. Heart rate variability (HRV): A sustained decline in HRV over 5 consecutive days is an objective early indicator of overtraining
3. Profile of Mood States (POMS): A chronically elevated total score (increased negative mood) is an important psychological indicator of OTS
4. Morning self-rated fatigue score (1–10): If it remains ≥ 7 for an extended period without significant improvement, the plan must be adjusted

Differentiating Normal Fatigue vs OTS

A Systematic Plan for Returning to Training

There are no shortcuts in returning from OTS; forcing a return to high intensity will only prolong the suffering:

Phase 1: Complete Rest (2–4 weeks)

• Stop all organized training
• Replace with “active recovery”: 30 minutes of walking, yoga, or light swimming daily
• Prioritize sufficient sleep (8–9 hours per night), with naps if needed
• Comprehensive nutritional support: ensure daily caloric intake is no less than 1.2 times basal metabolic rate, especially carbohydrates

Phase 2: Light Recovery Runs (4–8 weeks)

• Use “feels easy” (RPE 3–4/10) as the sole criterion
• Start with distances of 3–5km, increasing by only 1km every 2 weeks
• No pace targets; ditch the GPS and focus only on how you feel
• Run at most 3 times per week, ensuring adequate rest days

Phase 3: Progressive Return (after week 8)

• Resume at 50% of normal training volume, taking 6–8 weeks to return to baseline levels
• Redesign the training plan: incorporate “deload weeks” (reduce training volume by 30–40% for one week every 3–4 weeks)
• Make heart rate monitoring a daily habit: use heart rate zones instead of pace targets for a more accurate assessment of recovery

Practical Prevention Tips

1. Schedule rest: Plan a deload week every month and a 2–4 week complete transition period each year
2. Sleep is part of training: Track sleep quality in your training log with the same importance as running data
3. Don’t follow others’ plans: High-volume training shared by friends on social media may not suit your recovery capacity
4. Learn to “cut training”: When your body feels off, cutting the workout is a better decision than forcing through it
5. Manage stress: During periods of high work or family stress, reduce training volume accordingly—training is part of your total life stress

Conclusion

Overtraining syndrome is the cruelest warning in running—the harder you push, the further you fall back. Understanding and respecting the body’s recovery needs is the only way to let training truly accumulate. Your body doesn’t record how much you ran, but how much you recovered—a phrase every serious runner should take to heart.

Related Reading

• Identifying, Preventing, and Fully Recovering from Overtraining Syndrome (OTS)
• Recognizing Chronic Fatigue in Runners: Early Warning Signs of Overtraining Syndrome
• Warning Signs of Overtraining in Running: How to Identify Overtraining Syndrome
• Youth Sports Injury Prevention: Identifying and Preventing Overtraining Syndrome