This article can be useful to those who want to improve their results instead of jogging for health purposes. Below we are going to give details on how and why to to use intervals in the training process to get prepared for a marathon.
What is interval training?
Intervals are short distances, generally ranging from 200 m to 1600 m (0.12-1 mile).
Interval training is running with alternating stretches in the anaerobic zone and short stretches in the aerobic zone.
Intervals can be measured in different ways: by periods (minutes) or by distance (meters/feet). The number of fast intervals at each workout, their length and running speed are calculated individually.
Interval training develops endurance and strength and contributes to speed improvement. If your goal - to learn how to run faster and build up stamina, then you can include interval training in your program. Such workouts will significantly increase your fitness level and help smartly allocate your body resources for each distance.
The method of interval training is based on sets, i.e. for during the workout you need to perform several running sets for the chosen distance. The main task of interval training is to keep going as long as you can, working at a level of 95-100% of VO2 max (maximum oxygen consumption).
VO2 max – is the amount of oxygen absorbed by the human body per minute. It indicates the ability of the body to oxygenate muscles and the ability of muscles to utilize this oxygen for physical work. The higher VO2 max athletes have, the more effective their bodies can process oxygen – the main energy source for long distance running.
This indicator is an important indicator of aerobic power. It is believed that it VO2 max is the factor that limits or affects the performance in cyclic sports.
Experts agree that the key principles of interval training are:
- intensity levels;
- interval duration;
- rest between intervals;
- total amount of run for one interval session.
As noted by one of the famous experts, Jack Daniels:
Optimizing the VO2 max, in my opinion, is the most important advantage of interval training.
He also notes that when running at a given interval tempo, the athlete's body reaches the VO2 max in about 2 minutes.
Types of interval workouts
Interval workouts can be divided in 3 groups:
- Basic. The speed you run the workout intervals is equal to the speed you plan to choose for the competition distance.
- Fast. The running speed is much higher than in the first case, but the distance is shorter.
- Long. The distance segments are longer, but the speed on each segment is lower than in the main intervals.
In the process of high-intensity work lactic acid is released in muscles, so the body begins to neutralize it due to special enzymes. With time and with proper training muscle fibers become more resistant to acidification. Therefore, mountain trails cause less difficulties in well-trained athletes in comparison to beginners.
Besides, interval workouts are considered very effective for fat burn. People, who use interval running workouts, drop 12.4% of fat in the first 6 weeks. It happens because due to intense loads the body needs to spend more calories not only during the training session, but also after the workout is complete.
Interval training is different not only in the number of distance segments, their length and running speed, but also in the landscape characteristics (running through the stadium, running on rough terrain, running into a short climb, etc.).
What you need to know about interval training
The duration and intensity of running in segments is important. To reach the level of VO2 max, you need to run with a certain level of intensity. It is necessary to understand the difference between the intensity and running speed. It is the intensity that is the key concept when we talk about the load.
For example, the speed of running through the stadium and the speed of running through heavily-crossed terrain vary considerably, even though the same athlete runs the same distance in both cases, at the VO2 max level.
Experts consider intensity the best indicator, which takes the athlete to the VO2 max level. It is noted that working out with excess intensity does not improve the aerobic physiological mechanisms of our body. For example, if you run 10x400m, and the first round you run too fast (exceeding the planned tempo), then the following rounds will be completed much slower, at a pace that doesn’t help reach VO2 max. Eventually you get a hard workout without reaching the desired training effect.
As noted earlier, the length of interval segments varies and depends on the specific task in your training plan.
Long intervals increase the lactate threshold. World-famous coaches in their works note that without progress at distances of 3 km and 5 km (2 and 3 miles) it is much more difficult to improve their results in a half-marathon and a marathon. This is because the lactate threshold cannot exceed the VO2 max. Consequently, if your indicator of maximum oxygen consumption remains the same, then the marathon results will reach a certain level and stop improving.
Basically, interval training is carried out, guided by the running time of the distance, and not by the heart rate. However, heart rate values are considered when analyzing the work done.
It is important to understand that one interval workout won’t give any benefits. It’s better to save energy that spend it with no use. The effect is accumulated only after the month-long interval training program.
Rest between the intervals is better to spend jogging. Jogging contributes to the utilization of lactic acid and maintains the muscles in an elastic state. It is useful for preparing for the next round. Active recovery at times reduces the level of lactic acid in muscles, a lot faster than passive rest.
Fartlek
One of the most famous types of interval training is fartlek ("speed play"). It is a fundamental workout type in any program aimed at preparing athletes for medium and long distances.
Fartlek is a kind of interval circuit training, which varies from anaerobic sprint to jogging in the aerobic zone.
Fartlek allows you to mix different types of running in one workout. The general rule is that the load intensity should be in the range of 60-80% of the maximum heart rate. Make sure you include warm-up and cool-down in your workouts to prevent injuries.
Fartlek sessions can be long or short, light or hard, depending on what workout purpose you have. All the principles that concern ordinary interval work apply to fartlek. The difference is that during the fartlek athletes can added alternating run at a pace below the VO2 max tempo. For example, the first interval is performed at the VO2 max level, that is, almost at the maximum heart rate, then jogging as active rest, and then the interval at the threshold tempo.
Why Distance Runners Need Interval Training
Interval training for runners are necessary to develop speed-strength qualities and build up better stress adaptation
Facts: the essence of interval training for those who focus on the heart rate is alternation of high-intensity work (90-95% of the maximum possible speed, heart rate 180 BPM and more) and active rest (fast walking or jogging) in the aerobic zone, at the heart rate of 120-130 BPM). Interval training is not recommended for beginners for the first couple of months.
Interval training is one of the most difficult type in the entire training process. Interval training should not be included in the weekly plan more than 1-2 times. This is done so that the body can ‘digest’ the load. You can use standard intervals or fartlek.
To obtain the desired effect and reduce the risk of overtraining, interval training should be tailored to the individual characteristics and capabilities. The best way to do this is to ask an experienced coach. Or athletes can do that on their own through trial and error. Each professional coach keeps their techniques a secret. They include interval speed calculations and recovery time for each athlete. These parameters are based on many factors.
