how and why to run intervals

This article will be useful to those who not only want to run for fun, but also to improve their results. How and why to use intervals in the training process, we will answer in detail in this material.

What is the running interval

The intervals are short distances, usually ranging from 200m to 1600m. Interval training is running that alternates between anaerobic rounds and short aerobic rounds. Intervals can be measured in different ways: periods (minutes) or distance (meters). The number of fast intervals in each workout, their length and speed are calculated individually.

Interval running builds endurance and strength and improves speed performance. If your goal is to learn to run faster and build endurance, you can include interval training in your program. They will greatly increase your level and prevent you from turning into a Phoenix bird, which will burn with each run and then rise from the ashes.

Why run intervals when training for a marathon?

The interval training method is based on repetition, that is, in one workout, you need to perform a certain number of repetitions of each segment. The main objective of interval training is to last as long as possible while working at the level of 95-100 MPC (maximal oxygen consumption).

The MIC is the amount of oxygen absorbed by the human body per minute. That is, the body’s ability to saturate the muscles with oxygen, which must also process this oxygen well. The higher an athlete’s MPC, the more efficiently their body will process oxygen, which is the main source of energy when running long distances.

This indicator is an important criterion for aerobic power. It is believed that it is the IPC that is the factor that limits and affects performance in cyclical sports.

Experts agree that the important components of interval training are:

  • intensity levels;
  • interval duration;
  • recovery between intervals;
  • total stroke volume for the interval session.

As one of the famous experts, Jack Daniels, noted: “Optimizing the MPC is, in my opinion, the most important benefit of interval training.” He also notes that when running at a given interval pace, the athlete’s body reaches CPI in about 2 minutes. It should be noted that running at BMD is also associated with running at maximum heart rate.

Types of interval training

It is customary to subdivide the current interval into three types:

  1. Basic. The speed at which you run intervals in training is equal to the speed at which you plan to run the full distance in competition.
  2. Fast. The scrolling speed is much higher than in the first case, and the segment length is shorter.
  3. Long. The segments are longer, the speed of each segment is lower than in the main intervals.

During high-intensity work, lactic acid is released into the muscles, and the body begins to neutralize it with the help of special enzymes. Over time, with adequate training, the athlete synthesizes muscle fibers that are more resistant to acidification. Therefore, a well-trained athlete does not have great difficulty in overcoming mountain slopes, unlike a beginner.

Among other things, interval training is believed to be very effective in burning fat. Interval runners lose 12.4% fat in the first 6 weeks. The reason lies in the fact that such a rhythm causes the body to burn more calories not only during the session, but also after it is over.

Interval training is different, not only the number of segments, their length and speed, but also the characteristics of the landscape (crossing the stadium, running on uneven terrain, running in a short uphill, etc.).

Why run intervals when training for a marathon?

What you need to know about interval training

The duration and intensity of running segments are important. To reach the IPC level, you must only run at a certain level of intensity. You need to understand the difference between running intensity and running speed. Intensity is the key concept when talking about load.

For example, running speed in a stadium and running speed over rough terrain differ significantly, despite the same athlete running the same segment both there and there at the IPC level. Experts call intensity the best indicator that brings an athlete to the IPC level. It should be noted that excessive intensity work does not improve the aerobic physiological mechanisms of our organism.

For example, if you are running a 10x400m job and you run the first stage too fast (above your expected pace), then subsequent stages will be much slower, at a pace that does not go into IPC mode, and in the end you will get exhausting work, not achieving the desired effect of training.

As stated earlier, the length of interval segments varies and depends on the specific task in your training plan. Long intervals increase the lactate threshold.

World-renowned coaches note in their books that without progress over 3 km and 5 km distances it is much more difficult to improve results in half-marathons and marathons. Indeed, the lactate threshold cannot be higher than the MIC. Therefore, if your maximum oxygen consumption remains the same, the results on the marathon, reaching a certain level, will stop increasing.

Basically, interval training is performed, focusing on the running time of the segment, not the pulse. But the pulse values ​​are then taken into account in the analysis of the work performed.

It is important to understand that interval training will not work. It is better not to stress at all than to force in vain. The effect brings only one cycle of interval training for a month.

Recovery between stretches is best done with light jogging. Jogging promotes the use of lactic acid and maintains muscle elasticity, which is useful in preparing for the next intense session. Active recovery reduces the level of lactic acid in the muscles much faster than passive rest.

Read on the subject: Human running speed: average, maximum, record


One of the most famous types of interval training is fartlek (“playing with speed”), one of the fundamental workouts in any training program for medium and long distance running. Fartlek is a type of interval cycling training that ranges from anaerobic sprints to jogging (in the aerobic zone). Fartlek lets you mix different types of running in one workout.

The general rule is that the intensity of the load should be between 60 and 80% of the maximum heart rate. Also, for the prevention of injuries, it is necessary to include a warm-up and a hitch in the program.

What is a fartlek and how to perform it

Fartlek sessions can be long or short, light or hard, depending on your goal for the workout. All the principles that apply to work at regular intervals apply to fartlek. The difference is that during fartlek, running alternations at a lower pace than IPC pace can also be added.

For example, an athlete performs an interval at the IPC level, i.e. almost at maximum heart rate, then a standard rest in the form of a slow run, after which he switches to the interval at a threshold rate.

Interval training of runners is necessary for the development of the qualities of speed-strength and adaptation to stress. By the numbers: The essence of interval training for those who are more pulse-driven is alternating high-intensity work (90-95% of maximum possible speed, heart rate 180 bpm and above) and active rest (brisk walking or jogging) in the aerobic zone, the pulse is about 120-130 beats / min). For beginners, it is best not to do intervals during the first two months of your classes.

Interval training is one of the hardest parts of the whole training process. Interval training should be included in the weekly plan no more than 1-2 times. This is done so that the body can “digest” the load. These can be standard intervals or fartleks.

In order to achieve the desired effect and reduce the risk of overtraining, interval training should be tailored to the individual characteristics and abilities of a particular person. It is better to have an experienced trainer to do this. Or the athlete himself through trial and error. Every professional trainer keeps their technique secret, calculating the speed of running intervals and recovery time for each individual athlete, based on many factors.

If you don’t have a trainer, learn to train on your own.