Coaches See Marathoners Make These 7 Mistakes Again and Again—Here’s How to Avoid Them

Thomas HenggeNell Rojas had the perfect setup for a running career if there ever was one: She was born and raised in Boulder, Colorado, a town that became a running mecca after Frank Shorter, the only American with two Olympic medals in the marathon, made it his home in 1970 and opened a running store there. Her father, Ric Rojas, is a local legend and coach who won the inaugural 1979 Bolder Boulder, the biggest 10K race in the U.S., beating Shorter in the process. Her mother, Mary Dahlstrom, was also a marathon runner (who trained for her first, the 1978 Honolulu Marathon, using a Runner’s World training plan).And yet, despite pretty much growing up on the track, Nell Rojas favored soccer and, even more, basketball. She was drawn to the physical challenge and spent hours practicing free throws and dribbling until dark. “I was very athletic growing up, bigger and stronger than the boys and girls until high school,” she says. Her parents supported her no matter what sport she decided to pursue.But truth be told, Ric Rojas was delighted when Nell decided to give running a chance. “I did okay,” says the future Altra athlete. “I think I was third at state one year, that was my best in cross country.”By the time she attended Northern Arizona University, Nell did more than okay. “I ended up being the best runner on the team, getting a full scholarship my last year, making it to nationals in the steeplechase,” she says. After college, though, she felt burned out by running, and her father suggested she give a triathlon a try; he’d coach her.Nell loved it—the constant training and getting after it, sometimes for 12 hours a day. But triathlons ask for a lot; between juggling multiple jobs and working out, by her mid-20s, Nell found her life unsustainable. She let go of triathlon aspirations and opened a gym in Boulder. Using her exercise science degree, she started coaching Ironman triathletes. The independence and flexibility of being a gym owner made the desire to compete even stronger, and Nell started playing with the idea of training for an Ironman herself—a race consisting of a 2.4-mile swim, a 112-mile bicycle ride, and a 26.2-mile run for a total of 140.6 miles. That’s when her father said she should perhaps run a marathon first.Without knowing much about its high profile and PR friendliness, Nell signed up for the 2018 California International Marathon. Because she had run a speedy half marathon leading up to it, her friends suggested she might be able to qualify for the Olympic trials and hit the A standard. Nell had no clue what that meant; all she could think about was how scared she was of hitting the wall at mile 20—the point in a marathon that everyone was telling her about.She finished in 2:31:23—not only coming in seventh, but decisively qualifying for the 2020 Olympic Trials, which had a cutoff time of 2:37:00 for women. Ironman was history; Nell was all in on marathons.She’d go on to become famous for keeping her mileage lower compared to other elite runners and balancing it with more gym time. Just a few months after her debut at the distance, she won the 2019 Grandma’s Marathon, improving her time to 2:28:06.But even elite runners experience crappy races. At the cold, windy, and hilly 2020 Olympic Trials, Nell’s body couldn’t take any more fuel after mile 16, and she hit the feared mile-20 wall. She still finished, but the rest of the race felt like a “death march,” she says. Her outlook is that every marathon teaches you a lesson, and “unfortunately, I learned it during the Olympic Trials,” she adds.Her career-defining race (for now, her dream is to make the Olympic team) would be a year later at the 2021 Boston Marathon, where she came in as the top U.S. woman at 2:27:12. She’d also finish as the top U.S. woman the year after that in 2:25:57, and run her PR of 2:24:51 on the same course in 2023.The one thing she wishes she knew when she first started running marathons is the importance of rest. “Every single person is under-recovering,” she says.Nell has plenty more hard-earned insights and lessons that shape her approach as a coach with the Runner’s World program Master the Marathon. Still, her experience isn’t unique. Talk to any coach, and you’ll hear about common mistakes that can derail even the most dedicated runners. Here are the ones to watch for—and how to avoid them.—Pavlína ČernáThomas Hengge7 Marathon Training Mistakes Coaches See Athletes MakeWe asked coaches to share the common ones they see runners make time and time again—and how to get yourself back on the right track.You Run Easy Runs Too FastThis is one of the most common problems runners make when training for their first marathon, says Andrew Simmons, a USATF level 2 run coach. Newer runners building up to marathon distance often don’t initially grasp that the seemingly effortless pace during short runs won’t be sustainable for 26.2 miles.Coaches are typically able to identify this issue by noting spikes in a runner’s heart rate or a big decline in pace at the end of the run. “Runners often don’t understand the bigger-picture relationship with pace and heart rate,” Simmons says. “I work on explaining to them that if their heart rate is creeping up but the pace is staying the same, this is not efficient training.” You want your heart rate to stay pretty steady throughout the entire easy run—including the final miles.“Easy pace isn’t really a pace but more of a feeling,” adds Sara Manderscheid, a certified run coach in Boulder. “If I have a new runner who may not have a race result to go off of yet, I’ll tell them to try singing out loud when they’re running, and if they can’t or are gasping for air, they need to slow it down.”Trevor RaabNell Rojas believes that every marathon teaches you a lesson. She shares many of them in the Master the Marathon program, which she hosts.You Forget About Other Stress FactorsOne thing that’s key for recreational marathoners to remember is that running is your hobby and not your job. You need to consider other life factors, as they play a critical role in how you execute your training.“If you work a stressful job. . .that can absolutely have an impact on your training if you go immediately into a hard workout right after a high-stress workday,” Simmons says.After all, your body processes stress similarly, whether it’s coming from the physical demands of a run or the mental demands of your job. If you have a stressful week outside of your runs, maybe that means swapping out a speed workout for an easy run or taking an extra rest day and trying a practice like meditation so you don’t get burned out.Sleep is also critical, as it helps your body actually deal with stress. Research shows that even one night of sleep deprivation can affect your running performance the next day.You Overdo WorkoutsNikkia Young, a certified run coach and president of the Richmond Road Runners Club, encourages her athletes to keep group and social runs as part of their schedule, but only for easy runs—and to avoid basing pace goals for harder workouts on what you see others do.“A lot of new runners might think a few extra miles here and there are harmless, but if you regularly tack it on to what I assign for a week’s worth of training, it can be too much, too soon,” Young says. “When I find out someone has a regular group run that they enjoy, I remind them to make sure that the group dynamic doesn’t completely overrun them.”One other big mistake Simmons sees athletes make is doing back-to-back workouts. You may feel like yesterday’s workout wasn’t hard “enough” or you feel good today and decide to do a second workout, thinking that more workouts equals more fitness, he says. In reality, lighter sessions are almost always designed to help you recover and prepare for harder ones. Stacking too many hard sessions into a week can derail your training.Trevor RaabYou Try to Make Up for Missed TrainingIf you miss one run, there’s no need to overthink it, Young says. Just treat it as another rest day and pick up the training plan as it’s written for the following session.If you miss a week or more of training, Young typically suggests doing the same work the coming week. “Trying to stack missed mileage at the end of the week can do more harm than good,” she says, adding that you may need to adjust a plan to not ramp up too quickly.Simmons agrees. “Yes, you’re training for an endurance event, but ‘makeup miles’ often eat into your future profits,” he says. “If you missed miles because of scheduling issues, stress, or illness, you likely needed the rest, and trying to pile them all into an extra run is not the same as doing them as planned.”Thomas HenggeYou Fall Into a Comparison TrapIn the age of social media, it’s no surprise that runners can feel like they should be doing more based on what their friends or influencers post on Instagram or Strava.“I often have to remind athletes of their own goal and that where they’re at and are starting from is okay,” Young says.You Don’t Practice FuelingOften paired with going out too fast, this mistake is typically the result of not practicing and figuring out how much fuel you may need in training, and instead just going with whatever has worked for you in a half marathon, Simmons says.“This often causes athletes to explode near the three-hour mark because they’ve depleted their glycogen stores and did not fuel enough to keep up with the burn rate,” he says.The general recommendation is 30 to 60 grams of carbohydrates per hour, though some runners need more than that to make it through the later miles of a marathon. Dietitians also recommend fueling “early and often,” which could mean having your first gel 30 to 45 minutes into your run. “Some athletes will consume one to two gels for a three-and-a-half-hour race when they should actually be consuming five to six gels to fuel properly,” Simmons says.Practicing pacing and fueling during long runs will help you nail down your race day.You Keep Progress to YourselfIf you do have a coach, make sure you actually turn to them when you need them.“Communication is often the biggest hurdle for new athletes to overcome, and having a regular back-and-forth dialogue is key because the data on my side can only show so much, so I know to always ask my athletes, ‘How do your lungs, your legs, and your head feel?’” Manderscheid says. “I encourage my athletes to over-communicate versus under-communicate.”And if you don’t have a coach, there’s power in sharing your successes and struggles with family and friends. They can help you celebrate little wins that keep you motivated and deal with the disappointment if something doesn’t go your way, reminding you that any step forward is progress—no matter how small or slow.—Emilia BentonTrevor RaabWant Nell Rojas to Coach You Through Your First or Next Marathon?← Now that you know what not to do, are you ready to dial in your training? As the host of Master the Marathon: The Runner’s World Guide to Conquering 26.2, Nell Rojas will coach you from day one all the way to the finish line. Whether you’re targeting your first, next, or best 26.2 miles, our program lets you choose from a range of training plans based on your goals, and it offers expert guidance on injury prevention, strength training, long runs, tapering, fueling, and so much more! Available exclusively to Runner’s World+ members.Pavlína Černá, an RRCA-certified run coach and cycling enthusiast, has been with Runner’s World, Bicycling, and Popular Mechanics since August 2021. When she doesn’t edit, she writes; when she doesn’t write, she reads or translates. In whatever time she has left, you can find her outside running, riding, or roller-skating to the beat of one of the many audiobooks on her TBL list.Emilia Benton is a Houston-based freelance writer and editor. In addition to Runner's World, she has contributed health, fitness and wellness content to Women's Health, SELF, Prevention, Healthline, and the Houston Chronicle, among other publications. She is also an 11-time marathoner, a USATF Level 1-certified running coach, and an avid traveler.