The basic principle of an interval running workout is the alternation of segments done at high speed and periods using an easy pace or even complete rest.
There are no additional requirements for equipment: it is enough to have good running shoes. But this is not the only advantage of this type of training.
Benefits of Interval Running
Interval training improves athletic performance by increasing maximum oxygen uptake (VO2). The more oxygen the body can absorb and transport, the more energy is available to the muscles. Running interval training also allows you to use fast and slow types of muscle fibers, which helps to increase endurance.
Running is the best aerobic type of exercise. In other words, muscle activity is primarily provided by energy produced through the interaction of nutrients (primarily fats and carbohydrates) with oxygen. Therefore, the better the body can consume and transport oxygen, the more energy will be available for working muscles.
The parameter that indicates the maximum amount of oxygen we can take in is called maximum oxygen uptake, or MOU, which is measured in milliliters of oxygen consumed per kilogram of body weight per minute (mL/kg/min). This indicator affects running results at distances from 1500m to 5000m. So if your goal is to run 3k with the best result, increasing the MOU is a priority.
As mentioned earlier, while running, we get energy through processes that require oxygen. However, these energy-producing mechanisms cannot fully cover our energy needs during a long workout or when running faster. As a result, our body activates anaerobic energy systems, which leads to an increase in lactate and a decrease in acidity (pH) in muscle cells. In simple terms, fatigue and muscle pain result from the accumulation of hydrogen ions and the shift in the body’s pH to the acid side.
So, the threshold of anaerobic metabolism denotes the level of intensity at which there is a sharp increase in the concentration of lactate (and hence hydrogen ions) due to the rate of its formation exceeding the rate of its utilization.
Why is this so important to us? By improving our body’s ability to curb lactate buildup, we can maintain a faster pace (i.e., run faster and longer) and be less tired.
And finally, running efficiency. This parameter shows the oxygen consumption at a given speed expressed in milliliters of oxygen consumed per kilogram of body weight per minute. It has been scientifically proven that a 1 percent improvement in running economy achieved through training is associated with an improvement in a race time of approximately 0.4 to 0.7 percent. For the same MOU, a more fuel-efficient runner will use less oxygen (and therefore expend less energy) to run at a certain speed.
Running efficiency depends on many factors, including the runner’s weight and anthropometric data, stride length, contact time of the foot with the surface, the ratio of “fast” and “slow” fibers, and MOU.
The Main Types of Interval Running + Training Guide
Now that we have figured out what parameters affect our running results let’s look at the main types of interval training and how to use them to increase speed and endurance.
Before starting a workout, you shouldn’t take fat burners based on caffeine or other stimulants so as not to increase the pulse and pressure to dangerous levels. You should also refrain from sports drinks with a high content of fast carbohydrates, preferring electrolyte fluids. After a workout, you shouldn’t get into a hot bath or sauna. A cold shower is better.
Beginners shouldn’t start with interval training. Sudden loads are dangerous for unprepared joints and ligaments and can harm the cardiovascular system. Intervals are characterized by significant jumps in intensity, which is bad for people with hypertension or serious heart problems. People with diabetes who have suffered a heart attack or stroke should also avoid this type of training. And finally, you can not combine interval training with a carbohydrate-free diet.
Now, let’s talk more about 3 very useful types of interval running.
1. MOU Intervals
A scientific review examining optimal intensity for increasing MOU shows that high-intensity training (performed at 95-100% MOU) is the most effective way. This theory is supported by many famous coaches, including Jack Daniels and Pete Fitzinger.
The main idea is to accelerate your metabolism to a level close to the MOU and work on it for a long time, eventually improving the body’s aerobic capacity.
Interval running plan:
- Intensity: matches your current 3-5k race pace.
- Duration: Each interval is not more than 5 minutes or 600-1600m.
- Rest period: equal to or slightly less than the time spent in the previous segment or 50 to 90% of the time spent running the interval.
- Features: you must strictly adhere to the chosen pace; otherwise, you will not be able to achieve the desired training effect.
Examples of training: 600m – 7-10 times, 800m – 6-10 times, 1000m – 5-8 times, 1200m – 4-5 times, 1600m – 3-5 times.
2. Fartlek
This type of interval training is best for beginner runners or before the start of the season. The Fartlek alternates between hard accelerations and jogging.
Interval running plan:
- Intensity: From easy pace to high-end runs.
- Duration: 10-45 min.
- Rest period: none, more intense periods of running are followed by periods of jogging.
- Features: in most cases, fartlek training does not have a clear structure; you select the speed and duration of accelerations based on your own abilities.
Examples of training: 15 – 30 seconds fast, then 1-2 minutes jogging at an easy pace; 1-2 minute bursts at a moderate to hard pace followed by 2-5 minutes of jogging.
3. Hill Running Intervals
Research has shown that high-intensity hill training can significantly improve running endurance and athletic performance.
This can be primarily explained by the following positive effects and adaptations that hill running causes:
- A sharp increase in heart rate leads to an increase in stroke volume, the amount of oxygen that enters the working muscles, and, ultimately, BMD;
- develops strength and improves the body’s ability to remove lactate from the muscles during intervals and between repetitions;
- “fast” muscle fibers are involved in the work, which allows the runner to produce more energy and get less tired;
- improves running technique and improves the connection between the brain and muscles.
Interval Running Plan
- Intensity: near-maximum effort for 60-100 meters or 8-12 seconds followed by 1-3 minutes of walking or jogging
- Features: be sure to fully recover before the next set
- Workout examples: 4-10 reps of 60-100m on a hill with an incline of 5 -15 degrees.