Do you need to run long distances in training to be able to finish a marathon or a long-distance race?
Article revised and updated in February 2026
Few topics in running create as much uncertainty as the question of long runs in training. Here are some typical comments:
- “I’m training for Marathon X and I don’t have a single session longer than 2 hours 30 minutes in my plan.”
- “I’m preparing for an Ironman. Why am I not doing many long runs?”
- “I’ve read that I should do a long run every weekend.”
People often search in vain for extremely long sessions in 2PEAK training plans, as if continuous, monotonous “mile grinding” alone could increase the ability to withstand the marathon distance.
If it were that simple, there would be no need for individualized training planning—you could simply run as often and as long as possible.
Not only does this strategy fail to produce the desired results, but it can also increase the risk of injury.
In training logs, we observe that a large portion of the training volume is not run exclusively in the Base Endurance Zone (Z2), but rather as a mixture of different training zones. This leads to greater fatigue and does not deliver the intended training effects.
Z2 or Z3? The choice that shapes your progress
What do we really want?
A proper endurance base is the foundation without which no athlete can hope to remain strong and healthy, let alone make progress.
The term “endurance capacity” refers, in simplified terms, to the ability to use the energy available in the body efficiently. The mitochondria, the power plants of muscle cells, perform this function. They are stimulated and multiply when the athlete trains in the base endurance zone, for example at moderate intensity.
As soon as higher intensities are trained, and especially when continuous transitions occur between different intensity zones, this stimulation decreases. For this reason, 2PEAK recommends that during the base period, most of the training be performed in Z2 and verified through automatic training analysis.
During the base period, the majority of training—often more than 97% depending on the athlete and training volume—consists exclusively of Z2 work. This is complemented by coordination and targeted strength work, such as running drills.
Endurance capacity is particularly stimulated by training frequency. Training often is more effective than training very long. This can be seen in professional runners, who prefer to increase their volume by completing two separate sessions, in the morning and in the afternoon.
The advantages of multisport
Triathletes have a major advantage over “pure” runners: they can develop their endurance in other disciplines, which reduces the risk of injury. That is why 2PEAK favors these combinations. For runners only, it is often wiser to limit very long runs and switch to cycling after running in order to maintain mitochondrial stimulation while reducing impact load.
Today, true professional runners increasingly rely on a multisport approach. And even if some of them still perform very long sessions, this method cannot simply be copied without adaptation. The professional splits training into two or more sessions per day, receives massage after the effort, and begins recovery immediately.
We mere mortals often rush to the next appointment, still out of breath. The day’s efforts remain in the body until recovery sets in, with the hope of a good night’s sleep. This is where an intelligent and truly personalized training plan makes the difference. And that is exactly what 2PEAK offers you.
The main question
Test question: Can you run a marathon if you have not covered the distance at least x times beforehand?
Answer: You can! And as we have learned over time with 2PEAK athletes, it is often better that way. Believing that simply imitating the race distance in training is enough is an illusion.
A quick look at the extremes makes this clear. Does a 100 km runner train by repeatedly running 100 km races? Does a long-distance triathlete train 12 hours every session to be able to finish an Ironman in that time?
Long runs are exceptional events that heavily stress the organism. They deplete reserves and consequently require a proportional recovery period. In training, the goal is not to complete the entire event in advance. The goal is to build the elements that will be assembled on race day.
Training for tempo
Here is what matters: To go faster, you must train faster. And you can only do that if you are not overly fatigued by excessive running mileage.
Modern training aims to place the workload so that the different energy systems are repeatedly and systematically stressed. This does not mean mixing zones as in a fartlek. Rather, it means including planned tempo intervals and feeling “at home” at each of these paces.
This is where many recreational runners have a problem. Slightly exaggerated, they know only one “tempo.” A clear differentiation between various tempos makes it possible to plan training at all metabolic stages, depending on the individual state of recovery, and to create the stimuli necessary to truly run faster.
Any attempt to completely avoid intensities beyond Z2 only makes sense in very specific situations.
Endurance also develops by training in a slightly fatigued state, for example with several endurance sessions spread over multiple days of the week. However, the loads must be carefully adapted to the individual recovery rhythm. Here too, the 2PEAK plan does this for you.
A well-managed progressive reduction—that is, recovery after a planned phase of high intensity—in the period before the event ensures that you arrive at the starting line with fully charged batteries. And that you cover the distance at your best level, from start to finish.