Is Running Really "90% Mental"? Why Your Mind Might Be the Heaviest Weight You Carry

You've probably heard the maxim: "Running is 90% mental, 10% physical." It's more than motivational fluff—there's real science behind it. But it also oversimplifies the interplay between body and brain. Today, we'll explore the mental side of running, why it matters, how it works with the physical side, and what the best runners, coaches and scientists say.

The Mental Game: What It Does for Your Run

Pushing Past Fatigue

The moment your legs feel leaden, your breathing tightens, and your pace drops—that's often when the mind starts waving the white flag, not your muscle fibers. As sport-psychology researcher Sam Marcora explains: mental fatigue doesn't reduce muscle power or oxygen uptake—it increases the perceived effort, forcing you to quit earlier than your body might demand.

In other words: the brain has a "remote control" that can hit pause before the engine truly stops.

Dealing with Discomfort

Every seasoned runner knows the difference between "pain" (which comes) and "suffering" (which you let in). As one athlete put it:

"Every aspect of a run … offered me a choice: Is this a thought that will slow me down? Or can I find a perspective that will speed me up." — Deena Kastor

That shift—from "I hurt = stop" to "I hurt = choose to go on"—is largely mental rehearsal and mindset training.

Maintaining Focus

In a 10 K, half marathon or urban trail run through northern New Jersey, distractions abound: smartphone alerts, uneven sidewalks, changing weather. Mental strategies matter:

• Using mantras ("Just one more block…")
• Breaking a long run into micro-goals ("Run to the next lamp-post")
• Focusing on a single cue word ("Steady")

Sports psychology articles remind us that athletes who train their attention and internal dialogue outperform those who rely purely on physical preparation.

Building Confidence

The more you finish tough runs, the more you trust your brain when it whispers "you're done." That builds resilience. As Olympian Des Linden put it:

"We train our bodies. We train our guts. … It only makes sense that you can train your mind."

That confidence carries into your next race, your next hill workout, your next early-morning run in northern New Jersey.

The Physical Game: Your Body's Foundation

Physical Limits Matter

No matter how strong your focus is, it can't completely overcome zero fitness. The body's physiological processes—oxygen transport, muscular endurance, lactate threshold—are irreplaceable. As famed coach Jack Daniels would say: fitness builds your engine, but mindset drives you.

The Engine Under the Hood

When you run, your cells use ATP, your muscles contract repeatedly, your cardiovascular system pumps, your lungs supply oxygen. These are not optional. So the "10% physical" shorthand is a useful motivator, but not literal.

How They Work Together: Mind + Body = Performance

Complementary, Not Sequential

It's not "train body then mind" but "train both simultaneously." Your physical training builds capacity; your mental training enables you to draw on that capacity when it counts. As Runner's World put it:

"Most athletes fatigue mentally way before they fatigue physically."

So whether you're tackling a 5 K in [your local area], pacing a half-marathon or trying your first marathon, you need both.

What's the Real Ratio?

While "90/10" is catchy, many experts suggest more realistic ratios like 60/40 or 70/30 (mental/physical)—and for ultra or elite athletes pushing extreme distances, the mental share may actually climb higher. But the key is: you can't neglect either side.

Science & Stats You Should Know

• A meta-review in the journal Sports Medicine found that motivational self-talk significantly boosted endurance performance.
• In a controlled experiment, runners who performed a mentally fatiguing task beforehand quit earlier—even though their muscles and lungs were fine. That shows the brain can be the limiting factor, as researcher Sam Marcora explains in The MIT Press Reader.
• A study of recreational runners using tracking apps found that features like goal-setting, progress feedback and social sharing improved intrinsic motivation, reinforcing the mental side of training.

How This Applies to Runners in northern New Jersey

If you're running in and around northern New Jersey (towns like Pompton Lakes, Wayne, Riverdale etc.), here are a few things to keep in mind:

• Terrain: Rolling hills and varying surfaces mean you'll face physical challenges—so the mental edge helps when the legs are tired.
• Early morning runs: Running before sunrise means fewer distractions—but your mind may wander or resist. Use the mantra-or-micro-goal strategy (e.g., "Run to that red mailbox").
• Weather: Cold starts or humid finishes require mental prep—layering, fueling, pacing all demand mental clarity.
• Community runs & local races: Being part of a group helps your motivation, but when the pacing or weather gets tough, your mind must step up.

Practical Tips to Strengthen Your Mental Game

1. Visualize your entire session before starting: See yourself hitting your splits, finishing strong.
2. Break your run into segments: Instead of "10 miles," think "2 × 5 miles" or "4 × 2.5 miles."
3. Choose a mantra or cue word: Simple and repeatable like "steady," "forward," "one more," or "breathe."
4. Prepare for discomfort: In a workout, include a "pain chunk" (last mile faster) so your brain associates discomfort with finishing well.
5. Post-run reflection: Note down how you responded to mental fatigue or negative thoughts—then plan a "next time" strategy.

Where Mind Meets Miles

So is running "90% mental"? In a way, yes—if you mean that mental strength often determines whether you'll use the physical fitness you've earned. But don't misunderstand: the physical side is the foundation. The real secret is training both mental and physical. When you do that, every run in northern New Jersey, every early-morning session, every race starts to feel like a chance to test not just your legs—but your mindset.

The body will argue that there is no justifiable reason to continue. Your only recourse is to call on your spirit, which functions independently of logic. — attributed to Tim Noakes