You’ve most likely felt it earlier than: mile 14 feels manageable, possibly even comfy, however someplace round mile 17, all the pieces adjustments.
Your legs all of the sudden really feel like they’re encased in concrete.
Every step requires aware effort the place earlier than you had been gliding.
That psychological dialog begins: “Possibly I ought to stroll,” “I nonetheless have 3 extra miles,” “Why did I join this?”
Should you’ve skilled this brutal shift, the place what felt manageable all of the sudden turns into a survival march, you’re not alone and also you’re positively not undertrained.
Analysis by Benjamin Rapoport at MIT [1] demonstrates that greater than two-fifths of marathon runners expertise “hitting the wall,” with athletes working at 80-95% VO2max depleting glycogen mostly round mile 21.
That’s not stunning should you’ve been working lengthy sufficient, this brutal actuality of miles 16-20 is the place marathons are received or misplaced.
However right here’s the excellent news: the distinction between limping to the end with a 15-minute constructive cut up versus sustaining your tempo by way of these ultimate miles isn’t about toughness or expertise.
It’s about understanding what’s truly occurring in your physique and implementing confirmed methods to forestall metabolic failure earlier than it begins.
Let’s take a look at the science behind why these miles really feel exponentially more durable, and extra importantly, precisely methods to repair it.
The Science Behind Why It Will get Exponentially More durable
Your physique shops sufficient glycogen to gasoline roughly 90-120 minutes of working at marathon depth.
For many runners, this implies the tank begins approaching empty someplace between miles 16-20, relying on tempo and particular person physiology.
A computational examine [2] demonstrated that athletes with numerous leg muscle builds and glycogen densities, when working at 80-95% VO2max, hit glycogen depletion round mile 21, the space empirically recognized as the place marathoners mostly “hit the wall.”
However glycogen depletion isn’t the one villain on this story.
Cardiovascular drift progressively will increase your coronary heart price whereas sustaining the identical tempo, pushed by dehydration and rising core temperature.
Analysis on unfavorable splits [3] reveals that beginning conservatively reduces early cardiac stress and delays the rise in coronary heart price, sustaining extra secure cardiac output over time.
Your mind additionally will get concerned by way of central fatigue, growing serotonin ranges that cut back neural drive to recruit muscle fibers, creating the feeling of maximum fatigue even when your muscular tissues might theoretically proceed.
Merely put: a number of methods are failing concurrently, which is why discomfort at mile 10 turns into agony at mile 18.
The Fueling Technique That Saves Your Again Half
The largest mistake runners make is beginning their fueling too late.
Research present [4] that starting carbohydrate consumption at 30-45 minutes into your run, round mile 3-4, prevents the sudden power crash that derails so many lengthy runs.
Goal 30-60 grams of carbohydrates per hour for any run exceeding 90 minutes.
Take small, frequent doses of 8-15 grams at a time reasonably than overwhelming your intestine with giant quantities.
This strategy, backed by analysis on GI misery [5]permits your digestive system to soak up vitamins effectively with out inflicting cramping or runner’s diarrhea.
All the time pair concentrated carbs like gels and chews with water, by no means with sports activities drinks.
Combining concentrated sugars will increase the danger of intestine misery and people dreaded lavatory emergencies.
Your pre-run fueling issues simply as a lot as what you devour in the course of the run.
Eat your ultimate meal 2-3 hours earlier than your future, specializing in simply digestible carbs whereas avoiding high-fiber, high-fat, or high-protein meals that take longer to digest.
Analysis on GI administration [6] reveals that lowering fiber and fats consumption 1-2 days earlier than helps forestall mid-run lavatory emergencies that may derail your total effort.
The Pacing Self-discipline That Makes or Breaks You
Right here’s the place most runners fail: they begin too quick as a result of they really feel too good.
Analyses of world-class marathon occasions present {that a} majority of record-breaking performances observe both a good or slight unfavorable cut up profile.
Beginning conservatively permits for extra gradual glycogen utilization, preserving power reserves for the ultimate levels of the race.
Your first 5 miles ought to really feel nearly boringly straightforward, this isn’t the time to show something.
A examine on marathon pacing [7] discovered that 92% of marathoners fail to attain unfavorable splits not as a result of it’s inconceivable, however as a result of they lack the preparation and self-discipline required.
Place your self with runners 10-15 seconds per mile slower than your aim tempo initially.
Deal with effort over tempo in these early miles, resisting the temptation to exit laborious while you’re feeling recent.
The ten-10-10 methodology offers a sensible framework: run the primary 10 miles conservatively (10-15 seconds slower than aim tempo), settle into aim tempo for miles 11-20, then push laborious within the ultimate 10K should you’ve fueled and paced appropriately.
By beginning at a extra reasonable tempo, analysis reveals you cut back early pressure on the guts and delay cardiovascular drift, sustaining extra environment friendly oxygen transport to working muscular tissues.
Psychological Methods for When Your Physique Needs to Give up
Breaking down 20 miles into smaller, manageable segments makes the space really feel psychologically achievable.
Analysis on endurance psychology [8] demonstrates that “chunking”, mentally dividing a race into segments with particular objectives for every, will increase athletes’ perceptions of management.
Strive considering of a marathon as 6 x 7K runs, or 4 x 5-mile blocks, and even 3 x 40-minute efforts.
Set mini-goals and rewards for every chunk: “I’ll take my subsequent gel at mile 12,” or “I’ll reassess how I really feel on the subsequent water station.”
Research investigating mind methods [9] discovered that exterior dissociation, specializing in surroundings, crowds, and supporter indicators reasonably than your discomfort, seems best for non-elite runners and ends in later onset of fatigue.
Psychological arithmetic additionally offers highly effective distraction: counting homes, calculating remaining distance, or tallying up tempo splits retains your thoughts engaged when it needs to give attention to how a lot all the pieces hurts.
Develop educational mantras that maintain your type sharp when fatigue units in.
Brief, rhythmic phrases like “head up,” “robust end,” or “I’ve skilled for this” override doubt and fatigue whereas sustaining regular stride.
Analysis on self-talk [10] reveals that constructive affirmations enhance self-regulatory sources and improve decision-making throughout tough moments.
Fixing the Lavatory Emergency Downside
As much as 90% of endurance runners expertise some type of GI misery throughout coaching or racing.
Operating diverts blood out of your GI tract to your working muscular tissues (splanchnic hypoperfusion), which irritates the digestive system and triggers your physique to get rid of.
The mechanical jarring of working, mixed with stress hormones like cortisol and adrenaline, creates the proper storm for toilet emergencies.
Prevention begins 72 hours earlier than your future.
Analysis on pre-race vitamin [11] reveals that lowering high-fiber meals within the days earlier than prevents the sudden urge to go mid-run.
Get up early sufficient to permit your physique to naturally get rid of earlier than you begin working, this straightforward technique prevents numerous mid-run pit stops.
Morning espresso or tea may also help regulate bowel actions, however devour it a minimum of an hour earlier than working to present your self time to make use of the toilet.
In the course of the run, if GI misery strikes, instantly gradual your tempo, lowering depth decreases the severity of splanchnic hypoperfusion and sometimes offers fast reduction.
Strolling briefly reduces intestine motility and reduces urgency for many runners.
For runners who persistently battle regardless of correct vitamin and timing, over-the-counter anti-diarrhea remedy taken the night earlier than and race morning may also help management the scenario.
Simply experiment with remedy protocols throughout coaching runs, by no means on race day.
The Actuality: It’s Presupposed to Harm
Let’s be trustworthy about what you’re signing up for.
Miles 16-20 won’t ever really feel “straightforward” for anybody, together with elite runners who merely undergo sooner than the remainder of us.
What separates profitable lengthy runs from catastrophic ones isn’t the absence of discomfort, it’s the distinction between managed problem and full metabolic failure.
The physiological actuality is that working 20+ miles pushes a number of physique methods to their limits: glycogen shops deplete, cardiovascular effectivity decreases, core temperature rises, and neuromuscular fatigue accumulates.
Understanding that this problem is regular and anticipated, not an indication that you just’re undertrained or weak, helps you push by way of when each step feels inconceivable.
Your mind creates fatigue earlier than you attain true physiological limits, a protecting mechanism that tries to forestall injury.
Analysis on the central governor idea suggests you all the time have extra within the tank than you suppose, which suggests the voice telling you to cease at mile 18 is commonly mendacity.
Placing It All Collectively
Begin your future preparation 72 hours earlier than by lowering fiber and fats consumption.
Eat your ultimate substantial meal 2-3 hours earlier than the run, wake early sufficient for pure lavatory elimination, and start hydrating half-hour earlier than you begin.
Within the first 10 miles, run conservatively despite the fact that you are feeling nice, begin fueling at mile 3-4, take small frequent sips of water, and apply chunking by focusing solely on the present phase.
From miles 11-16, settle into your aim tempo if working even splits, proceed constant fueling each 30-45 minutes, and preserve constructive self-talk as problem will increase.
While you hit miles 16-20, anticipate discomfort and acknowledge it as regular and manageable.
Deal with one mile at a time, preserve your fueling even should you don’t really feel like consuming, and use mantras aggressively.
Should you’ve paced and fueled appropriately, that is truly the place you may push reasonably than simply survive.
Keep in mind: each runner who’s crossed a marathon end line has survived these miles.
You’re not weak for struggling, you’re experiencing precisely what the space calls for.
