Over-Under Intervals: Train Your Body to Handle Lactate
Over-under intervals are one of the most advanced and effective ways to improve performance near threshold.
What Are Over-Under Intervals?
These intervals alternate between:
- "Over" → above threshold (Z4–Z5)
- "Under" → slightly below threshold (Z3–Z4)
Without full recovery.
Why They Work
They train your body to:
- Produce lactate (over)
- Clear lactate (under)
- Stay efficient under stress
How It Feels
- Very challenging
- Burning sensation builds up
- No full recovery
Example Workout
Warm-up: 10 min easy Main set: 4 × (2 min over / 3 min under) Rest: 4 min easy Cool-down: 5–10 min easy
When to Use Them
- Advanced athletes
- Race preparation
- Threshold development
Common Mistakes
- Too much "over" time
- Not controlling the "under" pace
- Doing them too often
Over-Under vs Sweet Spot
| Over-Under | Sweet Spot |
|---|---|
| High stress | Moderate stress |
| Advanced | Beginner-friendly |
| Lactate focus | Aerobic focus |
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