How to Adjust Your Marathon Training Plan When Life Gets in the Way (Sick, Injured, or Just Exhausted)
1. Introduction
If you've ever trained for a marathon, you already know the truth: life does not pause for your training plan. You can be weeks into a perfectly structured schedule… and then suddenly you're sick, your knee hurts, work explodes, the kids get sick, or you just hit a wall of exhaustion.
I've been through all of it. In every marathon cycle, something has forced me to adjust. Early on, I made the classic mistakes: panicking, trying to "make up" missed long runs, doubling mileage, or pushing too hard too soon. All that ever did was derail my training further.
The biggest lesson I've learned? Adjustments are normal, expected, and manageable — as long as you do them intelligently. This guide walks you through exactly how to modify your marathon training plan safely based on real-life scenarios I've dealt with myself.
Key takeaway:
Missing runs doesn't ruin your race. Overreacting does.
2. The Golden Rules of Plan Adjustments
Before diving into scenarios, there are four rules every runner should follow when adjusting marathon training.
Rule #1: Never "make up" missed long runs
When you miss a long run, your brain says "I'll just do 18 miles tomorrow instead."
Your body says "Absolutely not."
Stacking long runs back-to-back can lead to:
- Overuse injuries
- Burnout
- Excessive fatigue
- Higher risk of illness
If you miss a long run, let it go. Long runs build gradually — not by cramming.
Rule #2: Consistency > perfection
Missing 1–2 workouts in a week is fine. Missing an entire week is manageable. Missing multiple weeks requires bigger restructuring, but it still doesn't mean your race is over.
Your marathon fitness comes from months of consistent miles, not one "perfect" week.
Rule #3: Rest is training too
Sometimes the best adjustment is doing nothing.
If life forces you to pause, your body often benefits from the recovery — especially during marathon build-up. Overtraining is far worse than undertraining.
Rule #4: When in doubt, be conservative
Running 26.2 miles injured is miserable. Arriving undertrained but healthy is almost always better than arriving fit but fragile.
If you're unsure how to adjust, err on the side of less.
Key takeaway:
Don't try to "fix" missed runs — manage them with long-term thinking.
3. Common Scenarios and Exactly How to Adjust
Let's walk through specific real-life scenarios and the exact adjustments that work.
SCENARIO 1: You Caught a Cold (Sick for 3–5 Days)
I've trained through colds, and the biggest mistake is pushing too soon.
When to rest completely:
- Fever
- Chest congestion
- Body ache
- Extreme fatigue
When light activity is okay:
- Mild head cold
- Slight fatigue
- Symptoms improving
How to adjust your plan:
Week you're sick:
- Skip all speed work
- Easy runs only, or full rest
Following week:
- Resume easy runs
- Skip speed work
- Keep long run but shorten by 10–20%
Week after that:
- Return to normal
- Reduce mileage by ~10% to stay safe
Example adjustment:
Before (original week):
- Tue: 6 miles easy
- Thu: Speed workout (5 × 1 mile)
- Sat: 18-mile long run
After (sick week):
- Tue: REST
- Thu: 3 miles easy or rest
- Sat: 12–14 miles max
Key takeaway: Don't rush a long run until you feel fully recovered.
SCENARIO 2: Minor Injury (Knee Pain, Shin Splints, etc.)
I've had both, and the first 72 hours are crucial.
Days 1–3:
- Full rest
- Ice 15–20 min, 2–3×/day
- Light mobility
- Reduce inflammation
Days 3–7: Evaluate
Is the pain:
- Gone? Gradually return
- Better? Cross-train + short runs
- Same or worse? Stop running and see a PT
If improving:
- Replace runs with: bike, elliptical, swimming
- Introduce walk/run intervals
- Reduce mileage by 50% for two weeks
- No speed work
When to skip the race:
- Stress fracture
- Severe IT band damage
- Acute knee ligament injury
- Pain that doesn't improve after 10 days
Maintaining fitness without running: Cycling and pool running preserve ~80–90% of your aerobic base.
Key takeaway: Treat injuries early and aggressively. Don't train through pain.
SCENARIO 3: Work Trip / Travel (Missing 5–7 Days)
I've had entire weeks derailed by travel.
Option A: Run while traveling
- Hotel treadmill
- Find a local park
- Short maintenance runs
You don't need perfect training — just maintain fitness.
Option B: Maintenance Mode
If you can't run much, aim for:
- 2–3 short easy runs
- Focus on sleep
- Stay hydrated
- Keep stress low
How to resume afterward
- Don't jump from zero back to 40 miles
- Ramp mileage over 3–4 days
- Reduce next long run by 10–30%
- Skip speed work that week
Key takeaway: A travel week becomes an unplanned recovery week — and that's okay.
SCENARIO 4: Complete Exhaustion / Burnout
This is more common than people admit.
Signs of burnout
- Elevated resting HR
- Struggling to hit paces
- Dreading every run
- Poor sleep
- Mood changes
Immediate adjustment
- Take 3–5 full days off
- No speed work for 2 weeks
- Reduce mileage by 20–30%
- Add an extra rest day weekly
Mental recovery
- Reconnect to your "why"
- Run without a watch for a few days
- Shorten routes you normally find daunting
Race strategy reconsideration: If burnout is late in training, adjusting your time goal may be necessary.
Key takeaway: Burnout is fixed with rest, not willpower.
SCENARIO 5: Major Life Disruption
Death in family, job loss, relationship issues — these moments matter more than finishing 26.2 miles.
If continuing training:
- Cut mileage in half
- Remove speed work
- Keep easy runs only
- Let running support you, not stress you
If life truly implodes:
It is absolutely okay to defer your race. Marathons will always exist. You only get one life.
Key takeaway: Training should support your life — not dominate it.
4. How to Modify Your Remaining Plan
If you missed 1 week (early training):
- Repeat the missed week
- Extend training by 1 week if possible
- If race date locked: remove one recovery week later
If you missed 2+ weeks (mid training):
- Do NOT try to catch up
- Restart at 70% of your previous mileage
- No speed work for 2 weeks
- Prioritize long runs and easy volume
- Consider adjusting your race goal by 2–5%
If you missed 3+ weeks (late training):
- Reevaluate race feasibility
- Cap long runs at 16–18 miles
- Prioritize staying healthy
- Consider switching from a time goal to a "run for experience" goal
Key takeaway:
The later the disruption, the more conservative you must be.
5. Tools & Technology for Dynamic Plan Adjustments
In the past, runners had two options:
- Manually adjust a spreadsheet
- Ask a coach and hope they respond in time
Now we have smarter tools.
Why adaptive technology helps
- Adjusts the entire plan, not just one week
- Removes guesswork
- Reduces stress around missed runs
- Provides consistent guidance
- Helps prevent overtraining
Real example:
On StrideRun, if you tap "I'm sick", the app:
- Reduces your current week
- Adjusts the following week
- Recalculates your training load
- Modifies long runs intelligently
You can even message: "I've been sick 4 days. What should I do?" This eliminates second-guessing.
Key takeaway:
Automated adjustments make marathon training more sustainable — especially for busy adults.
6. Mindset: The Mental Side of Adjustments
Adjusting your plan doesn't mean you failed. It means you're training like a mature athlete.
Every elite runner misses workouts. Every coach adjusts plans constantly. The best runners aren't perfect — they're adaptable.
Your job isn't to follow a plan flawlessly. Your job is to show up, stay healthy, and keep moving forward.
"The best plan is the one you can actually complete."
Key takeaway:
Flexibility is a skill — and it makes you a better runner.
7. Conclusion & Action Steps
You will miss runs. You will get sick. Life will interfere. That's normal — not a crisis.
Here's what to remember:
- Don't panic
- Don't try to catch up
- Use the rules and scenarios above as your guide
- When unsure, go conservative
- Protect your health above everything
If you want a plan that automatically adjusts without the stress, StrideRun can help. You can try it free at striderun.app — no credit card required.
Run smart. Stay adaptable. And remember: the goal isn't a perfect plan. The goal is to reach the starting line ready.