Over years of working with beginning ultramarathoners, we've noticed that most of them make the very same mistakes. Here is a list of the most common ones — and how to avoid them.

Mistake #1: Starting Too Fast

What happens: you're full of energy, the adrenaline is off the charts, everyone is running — so you run too. The first 10 km fly by easily, you're passing the crowd... And at kilometer 30 you realize the battery is dead.

Why it's bad: a fast start instantly burns through your precious glycogen. You slip into the “red zone,” accumulate lactate, overheat. By mid-race your fat engine still hasn't kicked in, while the carbohydrate one is already empty.

How to avoid it: run the first 20–30% of the distance 10–15% slower than your target pace. Yes, people will pass you. Don't give in to temptation! You'll pass them back in the second half, when they're crawling.

Mistake #2: Starting to Eat Too Late

What happens: “I'm not hungry yet, why eat?” you think. And you only start eating once you feel weak. But by that point it's already too late — the glycogen is gone, your blood sugar has dropped, you've “hit the wall.”

Why it's bad: from the moment you eat a gel to the moment the glucose enters your blood and reaches your muscles, 15–30 minutes pass. If you started eating when you already felt bad, you'll have to endure another half hour of crisis.

How to avoid it: start eating from the first hour of the race, before hunger appears. Set an alarm on your watch for every 30–40 minutes — the “time for a gel” signal. Don't wait until your body “asks for it.”

Mistake #3: Training in the “Gray Zone”

What happens: you run every workout at the same pace — not too easy, not too hard. You seem to be working, but the results don't improve.

Why it's bad: training in the “gray zone” (Zone 2–3, 70–80% of max heart rate) is the worst of both worlds. Too hard to develop the aerobic base, too easy to develop the thresholds. You accumulate fatigue without gaining adaptations.

How to avoid it: follow the 80/20 polarization principle: run 80% of your volume very easy (Zone 0–1, you can chat) and 20% hard (Zone 3–5, your breathing falls apart). Middling workouts should be kept to a minimum. You can calculate your zone boundaries in the training zones generator.

Mistake #4: Ignoring Recovery

What happens: “The more I run, the better prepared I'll be,” you think, and you run every day, piling up the kilometers. But instead of progress you feel chronic fatigue, irritability and poor sleep.

Why it's bad: progress happens not during workouts but during recovery. Without adequate rest, your body has no time to “repair” the microtraumas and get stronger. The result — overtraining and injuries.

How to avoid it:

include 1–2 full rest days per week (no running at all!);
sleep 8+ hours every night;
watch your HRV — if the number drops, give yourself an extra rest day;
after hard training blocks, do a recovery week (volume −30–50%).

Mistake #5: Running Only on Flat Ground

What happens: you're preparing for a mountain trail race, but you do all your training on asphalt in the park. In the race your quads get “destroyed” on the descents by mid-distance.

Why it's bad: the eccentric load of descending (when the muscle lengthens under load) requires specific adaptation. Without downhill training, your muscles aren't ready for those microtraumas.

How to avoid it:

if you're preparing for a mountain ultra, a significant share of your volume should be on hilly terrain;
if there are no mountains — run stairs and hills, do repeated ups and downs;
regularly include dedicated downhill workouts;
2–3 weeks before the race, go and scout the course.

Mistake #6: Not Testing Your Nutrition in Training

What happens: during the race you try a new gel handed out at an aid station. An hour later your stomach is so upset that you have to walk to the finish, stopping every 500 meters.

Why it's bad: during physical exertion the gut receives less blood (the muscles need it), and its reactions can be unpredictable. What digests fine at rest can cause a catastrophe on the run.

How to avoid it:

“nothing new on race day” — an iron rule;
test all your gels, bars and drinks on long training runs;
if you use caffeine — try it in training a month before the race;
find out in advance what will be at the race's aid stations, and train with that.

Mistake #7: Neglecting Strength Training

What happens: “Why lift? I'm here to run, not to haul a barbell,” you think. And you skip every strength session. In the race your knees start hurting at kilometer 40, your lower back aches, your ankles keep rolling.

Why it's bad: an ultramarathon is thousands of repetitions of the same movement under mounting fatigue. Weak stabilizer muscles and a weak core lead to breakdowns in technique, overloaded joints and injuries.

How to avoid it:

do a full-body strength session twice a week (30–45 minutes);
focus on: squats, lunges, planks, balance exercises;
train your ankles: single-leg stands, a balance cushion;
strengthen your core: it's your natural “corset” for running.

Mistake #8: Choosing a First Ultra That's Too Hard

What happens: you watch videos from UTMB (Ultra-Trail du Mont-Blanc) — 170 km, 10,000 meters of elevation gain — and think: “I want that too!” You sign up for a super-technical mountain trail with rock faces and roped sections.

Why it's bad: your first ultra is a learning experience. You need to understand how your body works over long distances, how to fuel, how to manage your pace. Add difficult navigation, altitude and weather risks on top — and the odds of a DNF rise sharply.

How to avoid it:

for your first ultra, choose 50–70 km;
preferably a non-technical course (paths, dirt, minimal rock);
with good support: frequent aid stations, course marking, medical assistance;
read the reviews: is this race recommended for beginners or not?
read up on the weather conditions — avoid extremely hot or cold races.

Mistake #9: Ignoring Your Body's Warning Signals

What happens: your knee aches slightly, but you keep training. “It'll pass on its own,” you think. A week later the pain intensifies, but the race is 3 weeks away and you can't afford to skip workouts. The result — an injury, a DNF and 3 months without running.

Why it's bad: a microtrauma that wasn't attended to in time turns into a serious problem. An ultramarathon can be postponed. Recovery from a serious injury can take months.

How to avoid it:

listen to pain: if something hurts for 2–3 days in a row, it's not a coincidence;
the 72-hour rule: if the pain doesn't go away after 3 days of rest — see a doctor or physiotherapist;
better to miss a week of training than 3 months because of an injury;
learn the signs of overtraining: poor sleep, elevated resting heart rate, irritability, loss of appetite.

Mistake #10: Having No “Plan B” for the Race

What happens: you've built a rigid plan: “I run 50 km in 7 hours at 8:30/km.” At kilometer 20 a downpour begins, the trail turns into a swamp, your pace drops to 12 min/km. You get upset, you get nervous, you lose motivation and you drop out.

Why it's bad: an ultramarathon is a game with many variables: weather, your stomach, fatigue, getting lost, blistered feet. A rigid plan collapses at the first surprise. Without flexibility you're doomed to disappointment.

How to avoid it:

set three goals: minimum (simply finish), optimum (make a target time), maximum (a top result);
keep your tactics flexible: if things go off plan, switch to the minimum goal;
think through in advance: “What if it rains? What if it's hot? What if I get lost? What if my stomach gives out?”;
the main plan for your first ultra is to finish. Time is secondary.

Remember: mistakes are part of learning. Almost every ultramarathoner has made most of these mistakes. The key is to learn from them and not repeat them twice. Good luck!