Overtraining: The Telltale Signs

8 min read

"More is better" — we've all thought that at some point, right? But that line of thinking often leads straight to overtraining. Overtraining syndrome affects 10-20% of endurance runners at some point. Personally, I've brushed against it a time or two. Recognizing it early can mean the difference between a week of rest and months of struggle.

Functional Overreaching vs. Overtraining

It's important to distinguish three stages:

  • Functional Overreaching — normal fatigue after a big training block. 2-3 days of rest, and you're back on track. This is the normal process of supercompensation
  • Non-Functional Overreaching — fatigue that persists despite 1-2 weeks of rest. Your performance plateaus or declines. Recovery takes 2 to 8 weeks
  • Overtraining Syndrome — a chronic state with hormonal, immune, and psychological disturbances. Recovery takes months — sometimes more than 6 months. This is truly the red zone

Warning Signs

Physical Signs

  • Resting Heart Rate abnormally high in the morning (+5-10 bpm above your normal)
  • Unexplained performance decline despite consistent training
  • Persistent heavy legs, even after a rest day
  • Increased susceptibility to colds and sore throats
  • Loss of appetite and unintentional weight loss

Psychological Signs

  • Irritability and mood swings (your loved ones often notice before you do)
  • Loss of desire to run — this is a very telling sign
  • Sleep disturbances (insomnia or non-restorative sleep)
  • Difficulty concentrating at work

Training Signals

  • Unable to maintain your usual paces
  • Disproportionate feeling of effort for easy workouts
  • Drop in estimated VO₂max on your GPS watch
  • Abnormally long recovery times between sessions

How to Prevent It

  • Follow the 80/20 rule (easy/intense)
  • Incorporate a deload week every 3-4 weeks
  • Monitor your resting heart rate every morning
  • Get enough sleep (7-9 hours)
  • Periodize your training

Risk Factors

  • Sudden increase in volume (> 20%/week)
  • Too much intensity, not enough base training
  • Additional work or personal life stress
  • Under-eating or restrictive dieting
  • Chronic lack of sleep

What to Do If You're Overtrained?

  1. Stop intense training — no intervals, no threshold runs. Only walking and very light jogging.
  2. Sleep — sleep is your primary recovery tool. Aim for 8-9 hours per night.
  3. Eat Enough — increase your intake of calories, carbohydrates, and proteins. Your body needs energy to repair itself.
  4. Reduce Overall Stress — training is just one stressor among many. Work stress, family stress, lack of sleep… it all adds up.
  5. Resume Very Gradually — follow a return-to-running protocol as you would after an injury.

My Takeaway: Overtraining is a tricky trap because its early signs resemble normal fatigue. My advice: watch for trends — an escalating resting heart rate, decreasing motivation, accumulating poor performances. When in doubt, a week of complete rest costs less than months of struggle.

Frequently Asked Questions

What are the first signs of overtraining?

Early warning signs include an elevated resting heart rate (+5-10 bpm), persistent fatigue despite rest, sleep disturbances, and an unusual drop in motivation.

How long does it take to recover from overtraining?

Mild overtraining typically resolves in 2-4 weeks of relative rest. Severe cases may require 2 to 6 months for complete recovery.

How to differentiate normal fatigue from overtraining?

Normal fatigue subsides after 1-2 days of rest. Overtraining persists despite rest and is accompanied by performance decline, irritability, and sleep disturbances.