It ’s the start line for your first — or maybe 10th — battle of Marathon . You ’ve got at least six months of consistent training under your belt , and you ’ve managed to run 20 statute mile at least a couple of time . Your trunk knows what it ’s like to fly the coop for several minute , and so does your brain .
But what exactly does your torso go through once the start gunman fire ? Here ’s a mile - by - mile breakdown of what happens when you hunt down a marathon .
The First 5 Miles
The excitement of a crowd means most runners start fast . That ’s a trouble , saysSiobhan M. Statuta , MD , a sport medicine primary care specialist at UVA Family Medicine in Charlottesville , Virginia , because you ’ll end up burn through your consistency ’s vigor stores earlier and fag faster . Not neat when you still have ( gulping ) more than 20 sea mile to go . “ dim and steady gets the job done , ” Dr. Statuta says .
Unlike short running events ( like a 5 K , or 3.1 mi ) , where you do n’t have to worry much about food or water , farseeing distances mean increased fret and a greater calorie suntan because you ’re out there longer , consort toMark A. Harrast , MD , a sports medicinal drug physician at UW Medicine and aesculapian music director of the Sports Medicine Center at Husky Stadium in Seattle , Washington .
A typical runner needs between 15 ounces ( for a smaller offset ) and 30 ounces ( for a larger runner ) of fluid every minute , Dr. Harrast say . To get a more precise measurement ofhow much water you ask , weigh yourself before and after an hour - long training run to see how much fluid you lost .
As far as food , you ’ll want to embark on submit in calories in the form of simplecarbohydratesafter an 60 minutes to an hour - and - a - half ofrunning , Statuta says . Simple carbs are sugars that break down quickly in the body , quickly providing you with fuel in the flesh of glucose , per theCleveland Clinic . Energy bars , Energy Department gels , firecracker , and pretzel all condition as simple carbs .
Mile 10
The miles are vanish by until your stomach starts to cramp — ouch !
Specific foods may cause digestive overturned in runners , too , Statuta says , so experimentation during grooming to retrieve what bothers your stomach the least . Still , there ’s no hope your gut will behave . gilbert hurt can happen at any time on a class , Statuta say , including before you cross the start line ( due to race - twenty-four hours jitters ) .
Miles 12 to 15
As the mile growth , wastefulness products ( byproduct of the body ’s energy - make procedure , include lactic acid ) start to establish in your muscular tissue , and the hammer of feet on paving material ( or trail ) originate to induce fatigue and soreness , according to Statuta .
You do n’t practice your muscular tissue as efficaciously when tiredness sets in , Harrast read , which can lead to strains , injury , and cramp . The best resolution is bar — be well - coach for race day . Harrast also recommends changing your stride for brusk outburst every international mile or so to give your consistence a new stimulus . Take bigger steps for a few seconds , and then take lowly whole step .
Hydration and fueling also bear upon the comfort of your muscle , so cleave to your food and body of water plan .
Miles 18 to 20
affair are going gravid , and then suddenly your legs turn to lead . Each stone’s throw feel likerunninguphill . You ’ve hit “ the wall , ” as runners like to call it . Some debate that the paries happens when you deplete your glycogen stores ( glycogen is the store human body ofcarbohydrates ) , while others , like Statuta , suggest that your torso just go slower as you wear upon .
There ’s also a genial element to consider . This is probable the utmost length you get in grooming , you ’ve still get geographical mile to go , and your encephalon is screaming , “ Why are we still doing this ? ! ”
If you do hit the wall , one minor sketch in militant athletes advise that assume in more saccharide may help . Also , try distraction or positive self - talking to great power through . And by mil 23 or 24 , the hollo of the bunch should serve put some pep back in your tone .
The Finish Line
The endurance contest is over , but your heart , lungs , and blood vessels are still amped up . It ’s imperative to keepwalkingeven after you cross the finish stemma — otherwise , origin can start to puddle in your lower extremity . “ The muscle tone relax , the vessels relax , so blood gets pull in down and aside from the learning ability , ” Statuta order . When pedigree is redirected from your mental capacity to your legs , you may become lightheaded and even founder . To prevent this , the American Heart Association ( AHA ) recommends walking at a ho-hum pace for at least 5 to 10 minutes .
Meanwhile , the kidney are working hard to filter waste from your descent . In fact , enquiry suggests that marathoners put up mild kidney harm on race day . That ’s because the consistence diverts blood from your organs to keep you moving forward , explains Harrast . Dehydrationcan restrict blood flowing through the kidneys , too . The good news is your kidney animate this damage on their own , so you do n’t have to do anything special .
However , if your urine plough brown or you ’re give severe muscle aches or cramp , you may have rhabdomyolysis , a potentially sprightliness - threatening aesculapian condition . Rhabdomyolysis get your brawniness to break down , leading toxic components of your brawn fiber to leak into your circulation system and kidney . This can cause kidney damage , per theCleveland Clinic . Seek immediate medical tutelage if you notice symptoms .
Your leg are n’t the only thing exhausted — yourimmune systemcan weaken during the three to 72 hours after a endurance contest , Harrast government note . But your immune system being down is n’t enough to give you a cold — you still call for to be exposed . All those people hugging you and richly - fiving you at the end ? They could be passing on a virus . sizable practices like catch enoughsleep , eating well , avoiding crowds , and practicinggood deal - wash habitsare key to protect yourself from post - race sniffles , Harrast says .
Jennifer Payne , MD , is a MD atPenn Medicine Lancaster General Health .
She pull in her bachelor-at-arms ’s from the University of St. Thomas , majoring in biochemistry and minoring in divinity . She was the first service learning assistant for the armed service con program and did blanket volunteer work with Open Arms of Minnesota during this time , including build a program library on multiple induration information . Sheobtained her MD fromtheGeorgetown University School of Medicine , where she was part of the first division to incline the Hoya Clinic for multitude without caparison . She also completed an elective course in medical writing and editing , lick withAmerican Family Physicianmagazine . Dr. Payne completed her abidance in kin medicine at Lancaster General Hospital and a primary care summercater medicine fellowship at Wellspan Health in York , Pennsylvania .
She has dish out on the board of the Mid - Atlantic Regional Chapter of the American College of Sports Medicine and attend in hold verbaliser and clinical case study for the medico portion of the conference .
She enjoys reading , all sport ( particularly Olympic weightlift ) , walk her dog , and spend time with her married man , sons , and their extended family unit .
Colleen Stinchcombe is a writer based near Seattle who writes about psychological , forcible , and relational health . She ’s peculiarly interested in drop a line explainers about health conditions , research how to pop and assert social relationships , and cut across evidence - based medical advice . Her work has appeared inSelf , Health , andWoman ’s Day , among other publications .
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