{"id":21589,"date":"2026-08-21T10:19:09","date_gmt":"2026-08-21T10:19:09","guid":{"rendered":"https:\/\/www.scienceinsport.com\/sports-nutrition\/?p=21589"},"modified":"2026-08-21T10:19:10","modified_gmt":"2026-08-21T10:19:10","slug":"fueling-utmb-what-the-mountain-asks-of-you","status":"publish","type":"post","link":"https:\/\/www.scienceinsport.com\/sports-nutrition\/fueling-utmb-what-the-mountain-asks-of-you\/","title":{"rendered":"Fueling UTMB: What The Mountain Asks Of You"},"content":{"rendered":"\n<div class=\"wp-block-group Introduction_with_Author_group\"><div class=\"wp-block-group__inner-container is-layout-constrained wp-block-group-is-layout-constrained\">\n<div class=\"wp-block-cover\"><img loading=\"lazy\" decoding=\"async\" width=\"1384\" height=\"430\" class=\"wp-block-cover__image-background wp-image-21591 size-full\" alt=\"SIS_UTMB_runner\" src=\"https:\/\/www.scienceinsport.com\/sports-nutrition\/wp-content\/uploads\/sites\/3\/2026\/08\/USBlog-FuelingUTMB-Header.png\" style=\"object-position:32% 59%\" data-object-fit=\"cover\" data-object-position=\"32% 59%\" srcset=\"https:\/\/www.scienceinsport.com\/sports-nutrition\/wp-content\/uploads\/sites\/3\/2026\/08\/USBlog-FuelingUTMB-Header.png 1384w, https:\/\/www.scienceinsport.com\/sports-nutrition\/wp-content\/uploads\/sites\/3\/2026\/08\/USBlog-FuelingUTMB-Header-300x93.png 300w, https:\/\/www.scienceinsport.com\/sports-nutrition\/wp-content\/uploads\/sites\/3\/2026\/08\/USBlog-FuelingUTMB-Header-1024x318.png 1024w, https:\/\/www.scienceinsport.com\/sports-nutrition\/wp-content\/uploads\/sites\/3\/2026\/08\/USBlog-FuelingUTMB-Header-768x239.png 768w, https:\/\/www.scienceinsport.com\/sports-nutrition\/wp-content\/uploads\/sites\/3\/2026\/08\/USBlog-FuelingUTMB-Header-1280x398.png 1280w, https:\/\/www.scienceinsport.com\/sports-nutrition\/wp-content\/uploads\/sites\/3\/2026\/08\/USBlog-FuelingUTMB-Header-40x12.png 40w, https:\/\/www.scienceinsport.com\/sports-nutrition\/wp-content\/uploads\/sites\/3\/2026\/08\/USBlog-FuelingUTMB-Header-55x17.png 55w, https:\/\/www.scienceinsport.com\/sports-nutrition\/wp-content\/uploads\/sites\/3\/2026\/08\/USBlog-FuelingUTMB-Header-100x31.png 100w\" sizes=\"auto, (max-width: 1384px) 100vw, 1384px\" \/><span aria-hidden=\"true\" class=\"wp-block-cover__background has-background-dim\" style=\"background-color:#3f4f33\"><\/span><div class=\"wp-block-cover__inner-container is-layout-constrained wp-block-cover-is-layout-constrained\">\n<p class=\"has-text-align-center has-large-font-size wp-block-paragraph\"><\/p>\n<\/div><\/div>\n\n\n\n<div style=\"height:30px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<div class=\"wp-block-group introduction_with_author_group is-vertical is-layout-flex wp-container-core-group-is-layout-4fc3f8e1 wp-block-group-is-layout-flex\"><div class=\"introduction_lower\"><div class=\"author-box\">\n                <div class=\"author-avatar\"><img data-del=\"avatar\" src='https:\/\/www.scienceinsport.com\/sports-nutrition\/wp-content\/uploads\/sites\/3\/2023\/11\/sis-logo-55x55.png' class='avatar pp-user-avatar avatar-50 photo ' height='50' width='50'\/><\/div>\n                    <div class=\"author-info\">\n                    <span class=\"written_by\">Written By<\/span>\n                    <h3>SiS Team <\/h3>\n                    <h6><\/h6>\n                <\/div>\n            <\/div><div class='duration_image'><img decoding=\"async\" class=\"lazy time_icon\" loading=\"lazy\" width=\"28\" title=\"28\" src=\"\/sports-nutrition\/wp-content\/themes\/sports-nutrition\/images\/time_icon.svg\" > 4 Min<\/div><div class='author_share'>Share <div class=\"share_buttons\"><div class=\"ss-inline-share-wrapper\"><div class=\"ss-inline-share-content\"><\/div><\/div><\/div><\/div><\/div>\n<\/div>\n<\/div><\/div>\n\n\n\n<div class=\"wp-block-group Parapgraph_group\"><div class=\"wp-block-group__inner-container is-layout-constrained wp-block-group-is-layout-constrained\">\n<div class=\"wp-block-group Parapgraph_group\"><div class=\"wp-block-group__inner-container is-layout-constrained wp-block-group-is-layout-constrained\">\n<h1 class=\"wp-block-heading has-text-align-left\">Fueling UTMB: What The Mountain Asks Of You<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">Most runners look at a 174-kilometer mountain race and see an aerobic engine problem. Build the heart and lungs, log the long runs, and the finish takes care of itself.<br><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Fitness, pacing, sleep and fuel all decide a day this long. <strong>Recent reviews suggest the one runners underrate is not the engine. It is the muscle taking the descents.<\/strong><\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Key Takeaways<\/strong><\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Many things limit a long mountain ultra, and muscle damage may be the overlooked one.<\/strong> Recent argument ranks it first, and it is not settled.<\/li>\n\n\n\n<li><strong>Running downhill causes the damage, and training on descents builds tolerance to it.<\/strong><\/li>\n\n\n\n<li><strong>60 to 90 grams of carbohydrate an hour suits most runners, once they have practiced it.<\/strong> Go to 90 to 120 only after months of practice.<\/li>\n\n\n\n<li><strong>What you eat between hard days might decide whether the training block holds together.<\/strong><\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>The Race Itself<\/strong><\/h2>\n\n\n\n<figure class=\"wp-block-gallery has-nested-images columns-default is-cropped wp-block-gallery-1 is-layout-flex wp-block-gallery-is-layout-flex\">\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"700\" height=\"446\" data-id=\"21569\" src=\"https:\/\/www.scienceinsport.com\/sports-nutrition\/wp-content\/uploads\/sites\/3\/2026\/08\/Josh-Blog-1-1.png\" alt=\"Josh Wade at UTMB Mont-Blanc\" class=\"wp-image-21569\" srcset=\"https:\/\/www.scienceinsport.com\/sports-nutrition\/wp-content\/uploads\/sites\/3\/2026\/08\/Josh-Blog-1-1.png 700w, https:\/\/www.scienceinsport.com\/sports-nutrition\/wp-content\/uploads\/sites\/3\/2026\/08\/Josh-Blog-1-1-300x191.png 300w, https:\/\/www.scienceinsport.com\/sports-nutrition\/wp-content\/uploads\/sites\/3\/2026\/08\/Josh-Blog-1-1-40x25.png 40w, https:\/\/www.scienceinsport.com\/sports-nutrition\/wp-content\/uploads\/sites\/3\/2026\/08\/Josh-Blog-1-1-55x35.png 55w, https:\/\/www.scienceinsport.com\/sports-nutrition\/wp-content\/uploads\/sites\/3\/2026\/08\/Josh-Blog-1-1-100x64.png 100w\" sizes=\"auto, (max-width: 700px) 100vw, 700px\" \/><\/figure>\n<\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">The flagship UTMB race covers 174 kilometers (108 miles) around the Mont Blanc massif, through France, Italy, and Switzerland, climbing roughly 9,900 meters (32,500 feet). The cutoff is 46 hours and 45 minutes. Winners finish near 20 hours.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The 2026 race starts on Friday 28 August at 17:45. <strong>That evening gun means almost everyone runs through a full night, and many through two.<\/strong><\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>What Breaks First<\/strong><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">A recent argument from ultra researchers puts something else first: <strong>muscle damage, and the fatigue that follows it.<\/strong> The cause is the braking your legs do on the way down. Steep descents and rough footing make the muscle lengthen under load for hours.<br><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">After one UTMB, a group of experienced male finishers had lost roughly <strong>35% of their quad strength and 39% of their calf strength<\/strong>. Most of that came back within nine days. Full baseline took around sixteen.<br><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Across two separate races, the Tor des Geants, a race twice as long and with two and a half times the climbing, produced <strong>less<\/strong> damage than UTMB. Runners held back early, and the accumulated sleep loss slowed them later.<br><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>The evidence suggests damage comes mostly from how hard you run the descents.<\/strong><br><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Aerobic fitness still matters. In one study of a 166-kilometer race, fitness accounted for about 65% of the difference between fast and slow finishers.<br><\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>Training To Resist The Damage<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Weekly mileage does the most work.<\/strong> In one study across a 50, 80 and 160-kilometer trail race, finishers had been running more weekly mileage than non-finishers. Those runners chose their own training, so treat it as a pattern.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The runners who finished the 160 averaged around 88 kilometers a week.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The more specific tool is downhill running. One hard descending session leaves your legs better prepared for the next one, for weeks afterward. In one small study of ten trained women, the second session felt noticeably less sore.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Space early downhill sessions 10 to 14 days apart.<\/strong> Bring them closer as your legs adapt. None of that training pays off unless you eat enough between sessions for the muscle to rebuild.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Climbing builds the same way. Start with short hill efforts, then sustained climbs. Add the steep descending last.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Leg strength work belongs in the plan, and quad strength predicted performance over 100 kilometers. One study found no relationship at 166.&nbsp;<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Keep time on real climbs and descents at the center of the plan.<\/strong> Strength work earns a slot around it.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>Fueling The Training Block<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Because appetite does not keep up with back-to-back mountain days, even elite ultra runners often fall short of their carbohydrate needs in high-volume weeks. Trail culture makes it worse. Fasted long runs get framed as toughness, and under-fueling degrades both the session and the recovery after it.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Chronic under-fueling is common, though how common is unclear. The costs are slower recovery, hormone changes, and training that stops making you fitter.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Fuel for the work required.<\/strong> High carbohydrate on your long mountain days and hard sessions, less on the easy ones. Treat the long mountain day like a race rehearsal and take carbohydrate every hour at the rate you plan to use on race day.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Because daily targets track the hours you train, easy days scale down while the weekly total holds<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td><strong>Training Load<\/strong><\/td><td><strong>Daily Carbohydrate<\/strong><\/td><\/tr><tr><td><strong>Under 1 hour a day<\/strong><\/td><td>3 to 5 g\/kg<\/td><\/tr><tr><td><strong>Around 1 hour a day<\/strong><\/td><td>5 to 7 g\/kg<\/td><\/tr><tr><td><strong>1 to 3 hours a day<\/strong><\/td><td>6 to 10 g\/kg<\/td><\/tr><tr><td><strong>4 or more hours a day<\/strong><\/td><td>8 to 12 g\/kg<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">A UTMB build sits in the 8 to 12 band on its biggest weeks. <strong>For a 70-kilogram runner (154 pounds), that is 560 to 840 grams a day.<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Field data from a multi-stage ultra found runners averaging about 7.5 grams per kilogram a day, short of the 8 to 12 the guidance calls for.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Recovering Between The Big Days<\/strong><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Damaged muscle refills its fuel stores more slowly than undamaged muscle, and it stops at a lower ceiling on the same carbohydrate intake.\u00a0<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The mechanism is well established. One study still found the shortfall three days later.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>After a long day of descending, give the refueling more time. Do not assume the same meal has done the same job it does after a flat run.<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Start with the daily total, because that does most of the work. <strong>Aim for 7 to 12 grams of carbohydrate per kilogram of body weight per day<\/strong> to restock fully across 24 to 36 hours. A 70-kilogram runner is looking at 490 to 840 grams a day.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Timing matters when the next session is close. <strong>Under a 24-hour turnaround, target 1.0 to 1.2 grams of carbohydrate per kilogram per hour across the first four hours.<\/strong> For a 70-kilogram runner, that is 70 to 84 grams an hour, with little reason to go higher.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Protein adds to your refueling only when carbohydrate falls short. When a real meal is not close, a recovery drink covers it. BETA Recovery carries 60 grams of carbohydrate and 30 grams of protein per serving, and REGO Rapid Recovery is the lighter choice. Food first when food is there.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>Carb Loading And Race Morning<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Load at 10 to 12 grams of carbohydrate per kilogram per day, across the 36 to 48 hours before the start.<\/strong> For a 70-kilogram runner, that is 700 to 840 grams.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Work up to the full amount over two or three practice days before race week.<\/strong> The top of that range is a lot of food.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A marathon mostly runs on the tank you start with, but a race this long drains it regardless, so loading only buys you the opening hours.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Race week is when the fiber comes down. White rice, pasta, bread, and bagels are easy to eat in volume and gentle on the gut.&nbsp;<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">With a 17:45 gun, race morning is barely race morning. You may never stand in Chamonix, but any afternoon or evening start raises the same problem and takes the same answer.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Eat a carbohydrate-rich lunch. Then have a final meal three to four hours out at 1 to 4 grams per kilogram, low in fat, fiber, and protein.<\/strong> Top up through the afternoon with toast, a banana, or a sports drink. Drink to thirst, since running dry slows the gut, and take sodium with your food.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">If you cannot eat early, loading well the day before and eating through the afternoon still gets you there properly fueled.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>The Hourly Plan<\/strong><\/h2>\n\n\n\n<figure class=\"wp-block-gallery has-nested-images columns-default is-cropped wp-block-gallery-2 is-layout-flex wp-block-gallery-is-layout-flex\">\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"700\" height=\"446\" data-id=\"21592\" src=\"https:\/\/www.scienceinsport.com\/sports-nutrition\/wp-content\/uploads\/sites\/3\/2026\/08\/USBlog-FuelingUTMB-Post4.png\" alt=\"image of information Table highlighting how to fuel UTMB\" class=\"wp-image-21592\" srcset=\"https:\/\/www.scienceinsport.com\/sports-nutrition\/wp-content\/uploads\/sites\/3\/2026\/08\/USBlog-FuelingUTMB-Post4.png 700w, https:\/\/www.scienceinsport.com\/sports-nutrition\/wp-content\/uploads\/sites\/3\/2026\/08\/USBlog-FuelingUTMB-Post4-300x191.png 300w, https:\/\/www.scienceinsport.com\/sports-nutrition\/wp-content\/uploads\/sites\/3\/2026\/08\/USBlog-FuelingUTMB-Post4-40x25.png 40w, https:\/\/www.scienceinsport.com\/sports-nutrition\/wp-content\/uploads\/sites\/3\/2026\/08\/USBlog-FuelingUTMB-Post4-55x35.png 55w, https:\/\/www.scienceinsport.com\/sports-nutrition\/wp-content\/uploads\/sites\/3\/2026\/08\/USBlog-FuelingUTMB-Post4-100x64.png 100w\" sizes=\"auto, (max-width: 700px) 100vw, 700px\" \/><\/figure>\n<\/figure>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Most runners work well at 60 to 90 grams of carbohydrate an hour.<\/strong> Above 60 grams, <strong>you have to have practiced it in training.<\/strong> Athletes who have built that tolerance over months work at 90 to 120 grams an hour.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Both 2025 UTMB winners trained at 120 grams an hour and raced near 90 to 94. Intake peaked around 110 before the major climbs, and dropped to 80 on easier ground.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Train at the ceiling. Race below it.<\/strong> Practice roughly 20 percent above your race-day target, so the gut has room to spare.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Gut training improves tolerance, meaning fewer stomach problems at a given intake. No good evidence says it raises how much you absorb.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Above 60 grams an hour you also need two different sugars, because one sugar uses one doorway in the gut wall and that doorway fills up. A second sugar opens another. Check the label for glucose and fructose, with glucose sometimes listed as maltodextrin.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The proportion matters too, because it decides how much each doorway moves. Blends aimed at the top of the hourly range run close to 1 to 0.8 glucose to fructose, and that intake still has to be practiced.<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td><strong>Hourly Target<\/strong><\/td><td><strong>Who It Fits<\/strong><\/td><td><strong>What You Need<\/strong><\/td><\/tr><tr><td><strong>30 to 60 g<\/strong><\/td><td>New to long efforts, or an easy day<\/td><td>One carbohydrate source<\/td><\/tr><tr><td><strong>60 to 90 g<\/strong><\/td><td>Most runners, races past four hours<\/td><td>Two sugars, practiced on long runs<\/td><\/tr><tr><td><strong>90 to 120 g<\/strong><\/td><td>Practiced this intake for months<\/td><td>Two sugars, rehearsed at race pace, evidence mixed above 100<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">BETA Fuel uses that blend and comes in fixed doses, which makes the arithmetic easy: <strong>40 grams of carbohydrate per gel, 80 grams per serving of the powder<\/strong>. A bottle of powder alone lands at 80, inside the range most runners can work in once they have practiced it.<br><\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Food, Flavor Fatigue, And Caffeine<\/strong><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Late in a race this long, getting the food down is the hard part.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Rotate flavors and textures, sweet and savory, and swap warm for cold.<\/strong> Ultra runners report flavor fatigue consistently.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Both 2025 UTMB winners ran on gels and drinks alone: one carbohydrate bottle, one water bottle, no solid food.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">At the front, intensity is high and heavy food slows the stomach. Longer hours at a slower pace make real food easier to handle, which is why UTMB aid stations serve bread, cheese, soup, and rice.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">If you want something solid in a pack, an Energy Oat Bar carries 40 grams of carbohydrate and 10 grams of protein.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Caffeine is there to get you through the night, and timing decides whether it works.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Take 3 to 6 milligrams per kilogram about an hour before the start.<\/strong> That puts a 70-kilogram runner at 210 to 420 milligrams. That dose is well supported.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><strong><strong>Bottom Line<\/strong><\/strong><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">The mountain tests whether your legs keep taking descents, and you build that in the months before the start. Fitness gets you to Chamonix and counts for plenty, but durability carries you around the massif.<\/p>\n<\/div><\/div>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Put a real descending session in your week, and eat afterward like it mattered.<\/strong><\/p>\n<\/div><\/div>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<div class=\"wp-block-group written_by_group\"><div class=\"wp-block-group__inner-container is-layout-constrained wp-block-group-is-layout-constrained\"><div class=\"author_written_by\">\n                                    <div class='written_by_title'>Written By<\/div>\n                                    <div class='written_content'>\n                                        <div class='written_by_avavtar'><img data-del=\"avatar\" src='https:\/\/www.scienceinsport.com\/sports-nutrition\/wp-content\/uploads\/sites\/3\/2023\/11\/sis-logo-55x55.png' class='avatar pp-user-avatar avatar-50 photo ' height='50' width='50'\/><span class='written_by_name_mobile'>SiS Team <\/span><\/div>\n                                        <div class='written_by_description'>\n                                         <div class='written_by_name'>SiS Team <\/div>\n                                         <div class='written_by_guest'><\/div>\n                                          <div class='written_by_introduction'>Supplying world-class knowledge, elite insights, and product recommendations to provide optimal performance solutions for all athletes across a wide variety of endurance sports.<\/div>\n                                          <div class='written_by_link'>\n                                            <a href='https:\/\/www.scienceinsport.com\/sports-nutrition\/author\/sisteam\/'>More articles by author<\/a>\n                                          <\/div>\n                                        <\/div>\n                                      <\/div>\n                                    <\/div>\n<\/div><\/div>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Most runners look at a 174-kilometer mountain race and see an aerobic engine problem. Build the heart and lungs, log the long runs, and the finish takes care of itself.<br \/>\nFitness, pacing, sleep and fuel all decide a day this long. Recent reviews suggest the one runners underrate is not the engine. It is the muscle taking the descents.<\/p>\n","protected":false},"author":158,"featured_media":21593,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[569,730,590],"tags":[13,393],"class_list":["post-21589","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-fueling-guides","category-ultramarathon-training","category-training","tag-energy-gel","tag-fueling"],"acf":{"subtitle":"","product_skus":"","post_banner":false,"duration_type":"time","duration_time":"9 minutes "},"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v28.4 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Fueling UTMB: What The Mountain Asks Of You<\/title>\n<meta name=\"description\" content=\"UTMB fueling. Fitness, pacing, sleep and fuel all decide a day this long. Recent reviews suggest the one runners underrate is not the engine. 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