You’ve in all probability felt it earlier than: mile 14 feels manageable, possibly even snug, however someplace round mile 17, all the things modifications.
Your legs all of a sudden really feel like they’re encased in concrete.
Every step requires acutely 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?”
In case you’ve skilled this brutal shift, the place what felt manageable all of a sudden turns into a survival march, you’re not alone and also you’re undoubtedly not undertrained.
Analysis by Benjamin Rapoport at MIT [1] demonstrates that greater than two-fifths of marathon runners expertise “hitting the wall,” with athletes operating at 80-95% VO2max depleting glycogen mostly round mile 21.
That’s not stunning in case you’ve been operating lengthy sufficient, this brutal actuality of miles 16-20 is the place marathons are gained or misplaced.
However right here’s the excellent news: the distinction between limping to the end with a 15-minute optimistic cut up versus sustaining your tempo by way of these remaining miles isn’t about toughness or expertise.
It’s about understanding what’s really taking place in your physique and implementing confirmed methods to stop 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 easy methods to repair it.
The Science Behind Why It Will get Exponentially More durable
Your physique shops sufficient glycogen to gas roughly 90-120 minutes of operating 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 research [2] demonstrated that athletes with varied leg muscle builds and glycogen densities, when operating 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 charge whereas sustaining the identical tempo, pushed by dehydration and rising core temperature.
Analysis on destructive splits [3] reveals that beginning conservatively reduces early cardiac stress and delays the rise in coronary heart charge, sustaining extra steady cardiac output over time.
Your mind additionally will get concerned by way of central fatigue, rising serotonin ranges that scale back neural drive to recruit muscle fibers, creating the feeling of utmost fatigue even when your muscle tissues might theoretically proceed.
Merely put: a number of programs 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 vitality 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 fairly 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 through the run.
Eat your remaining meal 2-3 hours earlier than your long term, 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 decreasing fiber and fats consumption 1-2 days earlier than helps forestall mid-run lavatory emergencies that may derail your complete 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 fair or slight destructive cut up profile.
Beginning conservatively permits for extra gradual glycogen utilization, preserving vitality reserves for the ultimate phases of the race.
Your first 5 miles ought to really feel virtually boringly simple, this isn’t the time to show something.
A research on marathon pacing [7] discovered that 92% of marathoners fail to realize destructive splits not as a result of it’s not possible, 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 at first.
Deal with effort over tempo in these early miles, resisting the temptation to exit laborious whenever 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 remaining 10K in case you’ve fueled and paced accurately.
By beginning at a extra average tempo, analysis reveals you scale back early pressure on the guts and delay cardiovascular drift, sustaining extra environment friendly oxygen transport to working muscle tissues.
Psychological Methods for When Your Physique Desires to Stop
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.
Attempt 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 fairly than your discomfort, seems simplest for non-elite runners and leads to 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 desires to deal with how a lot all the things hurts.
Develop educational mantras that hold your type sharp when fatigue units in.
Quick, 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 optimistic affirmations improve self-regulatory sources and improve decision-making throughout tough moments.
Fixing the Toilet 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 muscle tissues (splanchnic hypoperfusion), which irritates the digestive system and triggers your physique to remove.
The mechanical jarring of operating, mixed with stress hormones like cortisol and adrenaline, creates the right storm for lavatory emergencies.
Prevention begins 72 hours earlier than your long term.
Analysis on pre-race diet [11] reveals that decreasing 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 remove earlier than you begin operating, this easy technique prevents numerous mid-run pit stops.
Morning espresso or tea can assist regulate bowel actions, however devour it no less than an hour earlier than operating to offer your self time to make use of the lavatory.
Through the run, if GI misery strikes, instantly gradual your tempo, decreasing 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 constantly battle regardless of correct diet and timing, over-the-counter anti-diarrhea treatment taken the night earlier than and race morning can assist management the scenario.
Simply experiment with treatment protocols throughout coaching runs, by no means on race day.
The Actuality: It’s Speculated to Harm
Let’s be sincere about what you’re signing up for.
Miles 16-20 won’t ever really feel “simple” for anybody, together with elite runners who merely undergo quicker 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 issue and full metabolic failure.
The physiological actuality is that operating 20+ miles pushes a number of physique programs to their limits: glycogen shops deplete, cardiovascular effectivity decreases, core temperature rises, and neuromuscular fatigue accumulates.
Understanding that this issue is regular and anticipated, not an indication that you simply’re undertrained or weak, helps you push by way of when each step feels not possible.
Your mind creates fatigue earlier than you attain true physiological limits, a protecting mechanism that tries to stop harm.
Analysis on the central governor principle 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 usually mendacity.
Placing It All Collectively
Begin your long term preparation 72 hours earlier than by decreasing fiber and fats consumption.
Eat your remaining 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 though you are feeling nice, begin fueling at mile 3-4, take small frequent sips of water, and follow chunking by focusing solely on the present section.
From miles 11-16, settle into your aim tempo if operating even splits, proceed constant fueling each 30-45 minutes, and preserve optimistic self-talk as issue will increase.
Once you hit miles 16-20, count on discomfort and acknowledge it as regular and manageable.
Deal with one mile at a time, preserve your fueling even in case you don’t really feel like consuming, and use mantras aggressively.
In case you’ve paced and fueled accurately, that is really the place you’ll be able to push fairly than simply survive.
Bear 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.
