January enthusiasm is the best fuel to start, but the worst enemy for your joints: learn to manage the load so you don’t stop in February.
- The Trap: Mind ready, tendons not. The misalignment that causes damage.
- The Problem: You don’t need a crazy week to get hurt; just one “heroic” run out of parameters is enough.
- The Rule: Slow progression. Increase little, increase slowly.
- Listening: “Bad” pain is asymmetrical and doesn’t go away with a warm-up.
- Plan B: If it pulls, stop. Better to skip a day than a month.
The Trap: Enthusiasm + Body Not Ready
It’s January 4th. You have the new shoes bought for Christmas, the registration for a spring race, and motivation that could move mountains. You feel invincible.
Here, this is exactly the moment you get hurt.
The problem with January is the temporal misalignment: your cardiovascular system (heart and breath) improves quickly, giving you the illusion that you can push hard. But your structural system (tendons, ligaments, bones, and cartilage) is much slower to adapt to the load, especially if you come from a period of rest or Christmas “maintenance.”
You are mounting a Ferrari engine on the chassis of an economy car that has been sitting in the garage. If you accelerate to the max immediately, something will break.
The Concept of Spike (Even in a Single Session)
We often think that injuries only arrive if we drastically increase the total weekly mileage. True, but that’s not all.
Recent scientific research has introduced the concept of “Acute Load Spike.”
A study published in the British Journal of Sports Medicine in 2025 highlights how even a single workout with an excessive load compared to the habitual average (single run spike) drastically increases the risk of injury in the following days.
You don’t need to double your week: just going out one Sunday and doing 18 km when your recent maximum was 10 is enough. That single outing creates mechanical stress that tissues cannot absorb.
Add to this the classic rule: increasing weekly volume too fast is dangerous. Consolidated research (JOSPT) indicates that increases in weekly load greater than 10-15% are predictive of injuries.
4 Simple Rules for January
To navigate this trap month unharmed, follow these directives:
- The 10% Rule: Do not increase total mileage by more than 10% compared to the previous week. If you did 30 km last week, do 33 this week, not 40. (To learn more, read our guide on the 10+5+0 rule).
- The Non-Heroic Long Run: Don’t try to make up for lost time on the weekend. Your “Long Run” should never exceed 30-35% of your total weekly volume.
- Control Intensity: In January, build the base. Run slow. Use the 80/20 method: 80% of your runs must be easy, conversational. Speed, right now, is the enemy of continuity.
- Check Your Gear: Sometimes it’s not you, it’s the shoes. If they have passed 600-800 km or are years old, the midsole might be “dead,” increasing impact. Check the 5 signs of wear.
Early Signs to Listen To
The body always warns before breaking. The trick is to distinguish “good” fatigue (training effect) from “bad” pain (injury).
Use the 2-2-2 rule to evaluate every discomfort.
In general, worry if the pain is:
- Asymmetrical: Only your right knee hurts, not both.
- Pinpoint: You can point to the exact spot with one finger (bad sign), rather than indicating a vague area (often just fatigue).
- Persistent: It doesn’t go away after the first few minutes of warm-up; in fact, it gets worse while running.
Plan B: What to Do When You Feel a “Pull”
If you feel one of these signals, the biggest mistake is saying “I’ll run anyway, it will pass.” It won’t pass.
Stop immediately.
Replace running with low-impact activities for a few days. It’s the perfect time to use cross-training: swimming, cycling, or elliptical keep your stamina up without hammering your joints.
Remember: a smart runner isn’t the one who never stops, but the one who knows how to stop for a day to avoid having to stop for three months.