Long Run – The Key to Endurance
The long run is one of the most important runs in your training. It’s where you build endurance, mental strength, and efficiency—everything you need to run longer distances comfortably. These runs should feel challenging but controlled, pushing your body to adapt while staying in an aerobic zone.
By Quentin van Bentum | Last updated Feb 25, 2024
A Full Breakdown
Long runs are all about time on your feet. Unlike speed workouts or tempo runs, the goal isn’t pace—it’s about gradually increasing your ability to run longer distances without breaking down.
A common mistake runners make? Running their long runs too fast. If you’re finishing your long run completely exhausted, you’re not getting the full benefit. Instead, you want to stay in an aerobic zone (Zone 2-3), where your body efficiently burns fat for fuel and builds endurance.
The long run is the cornerstone of distance running, whether you’re training for a half marathon, marathon, or beyond.
What a Long Run Should Feel Like
- Steady and controlled – You should be able to talk, but the effort should be higher than an easy run.
- Heart rate in Zone 2-3 – This is the ideal range for endurance development (60-80% of max HR).
- Gradually increasing distance – Start with what you can handle and increase by no more than 10% per week.
- Longer than your other runs – Typically 1.5x to 2x the length of a normal run.
If you finish feeling completely drained, you’re most likely going too fast or not fueling properly.

Why Long Runs Matter
Long runs aren’t just about building endurance—they help your body adapt to running longer, strengthen muscles, and improve energy efficiency. They also train your mind to stay strong when fatigue sets in.
How Long Runs Help You Improve:
✔ Increase stamina – Helps your body adapt to running longer distances efficiently.
✔ Boost fat metabolism – Improves your body’s ability to use fat as fuel, critical for long races.
✔ Strengthen muscles & joints – Builds durability for long-term running success.
✔ Improve mental toughness – Teaches you to stay focused and push through fatigue.
How to Do a Long Run the Right Way
- Start at a conversational pace – Your goal is distance, not speed.
- Stay in Zone 2-3 – If your heart rate creeps higher, slow down.
- Fuel properly – If running over 60-90 minutes, bring energy gels, water, or sports drinks.
- Gradually increase distance – Stick to the 10% rule (increase no more than 10% per week).
- Recover properly – After a long run, hydrate, eat, and do light stretching to aid recovery.
The Key Takeaway
Long runs are of great importance with endurance training. Done right, they build strength, stamina, and mental toughness, setting you up for success in races and longer efforts.
The key? Stay controlled, pace yourself, and focus on consistency—not speed.