Threshold Running: All you need to know about it

When it comes to Threshold Running, the importance of ergometric evaluation — before starting the threshold training program — is of great importance. That’s because ergometric evaluation determines the physical condition of the athlete, at the time of the measurement.

Yet, there is the misconception that ergometric evaluation is performed when the athlete is in optimal physical condition. To clear things out, the evaluation measures the athlete’s physical condition at a given moment. This helps a coach set and configure a training program that meets the athlete’s needs, and goals at that time.

Essential ergometric tests for endurance athletes

One of the most well-known and essential tests that ergophysiologists perform on endurance athletes is the Maximal Oxygen Uptake. As one can gather, this evaluation measures the maximum amount of oxygen that can be absorbed and consumed by the athlete’s muscle cells for energy production, in a unit of time, during exercise. What’s more, the test offers additional data regarding the athlete’s physical condition, such as:

Maximum aerobic velocity

This is the maximum velocity that can be achieved, when performing a progressive velocity increase test to measure maximal oxygen uptake.

Maximum heart rate

The maximum heart rate of the athlete can be achieved during the progressive rate increase test to measure maximum oxygen uptake.

The aforementioned data are mainly collected by the occupational ergophysiologist performing the tests. Based on these data the scientist can outline the ventilatory thresholds necessary for the athlete to train effectively; and, achieve maximum results from the training process.

Through the ergometric evaluation, the athlete performs the same exercise protocol, and the measurement for lactation can also take place. With this addition, the occupational ergophysiologist is able to pinpoint the athlete’s lactation curve and extend the first (LT1) and second lactation thresholds (LT2) accordingly.

What is Threshold Running?

To better analyze Threshold Running, we need to expound on a few more things on the ventilatory threshold. Initially, the ergophysiologist identifies two ventilatory thresholds in the ventilatory curve — obtained from the test mentioned earlier. These are the first ventilatory threshold, and the second ventilatory threshold, respectively.

By locating these two points in the athlete’s curve, the scientist essentially demarcates the three training zones. The first zone is called moderate intensity and is defined as the first ventilatory threshold. The second zone is called heavy intensity and is located between the first ventilatory threshold and the second ventilatory threshold. Finally, the third zone is called severe (or high) intensity and is defined by the second ventilatory threshold up to VO2max. (Jones et. al 2010).

A more common form to indicate training zones is to divide the curve into 5 training zones; which is widely used in training. This way, athletes can better understand it; and it helps them execute their training better. To elaborate, the zones are divided as follows (Seiler et. al 2009):

  • 1st Zone: 45-65% VO2max, 55-75% HRmax
  • 2nd Zone: 66-80% VO2max, 75-85% HRmax
  • 3rd Zone: 81-87% VO2max, 85-90% HRmax
  • 4th Zone: 88-93% VO2max, 90-95% HRmax
  • 5th Zone: 94-100% VO2max, 95-100% HRmax

Depending on the goal of each athlete, the training should be preferably performed in the first or the second training zone. That is, if the athlete wants to achieve the adjustments that the body can withstand; in terms of the first or second ventilatory threshold, of course.

What does Threshold Running training include?

The biggest part of the Threshold Running training has to do with the lactate threshold. In other words, that is the point in the curve where there is an increase in lactic acid in the blood. To explain, this is the point where the body exceeds the stabilization phase of its normal factors and enters the phase of exponential increase. However, several studies on lactate thresholds have shown that there isn’t just one LT, but two: LT1 and LT2.

During the training process, the workouts that are demarcated in the first training zone (first threshold), are mainly utilized for long exercises; such as medium or long runs. These two types of training are essential for long-distance runners ,and are part of the athlete’s weekly schedule throughout their preparation. Due to the low intensity of these workouts, the athlete’s physiology changes at a very slow pace; which, in turn, allows them to maintain their rhythm during running for a long time, without fatigue.

Body adjustments when training in the first thresholds

Decreased heart rate 

With the Threshold Running method, endurance athletes gradually gain an increased stroke volume. This increase results in a decrease in heart rate, which is maintained at rest; hence, athletes maintain low heart rates, both when exercising and at rest.

Increased running economy

A few important parameters that affect the running economy are:

  • heart rate, 
  • respiratory volume, and 
  • the cardiovascular system

As long as there is an improvement in these parameters, the running economy of the athlete will also keep improving.

 Increased speed at the threshold level

Due to the overall physical improvement of the athlete, they manage to improve their speed at the threshold of lactation.

Shift of the curve to the right

Considering all of the above, in the ergometric evaluation we can determine the adjustments caused by the Threshold Running training. That is, by observing the displacement of the curve of the lactate. Naturally, this shift indicates its improvement.

The workouts aimed at the second ventilatory threshold, hence delimited in the second training zone, are mainly used for training known as the Tempo Run. These workouts are much shorter in duration as, at this intensity, the physiology of the body is disrupted at a faster rate and fatigue occurs much faster.

Body adjustments when training in the second thresholds

Decreased heart rate

Endurance athletes gain the ability to have an increased stroke volume. This increase results in a decrease in heart rate, which is maintained at rest, so athletes can benefit from low heart rates at rest, as well.

Reduced lactic acid accumulation in the blood

There is a positive correlation between aerobic capacity and the rate at which blood lactate is removed. So, the better the aerobic capacity, the higher the oxygenated blood percentages.

Increased VO2max

The increase in VO2max happens because it increases the maximum cardiac output as well as the number and size of mitochondria in skeletal muscle. So there is more blood circulation; and consequently more oxygen available to muscle tissues.

Increased speed at the threshold

Due to the improvement of all the normal parameters of the body, the athlete is able to improve their speed on the threshold of lactation.

Shift of the curve to the right

Based on all of the above, in the ergometric evaluation we can see all the adjustments that came with the training, by observing the displacement of the curve of the lactate, indicating its improvement.

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Threshold Running is a training method that serves specific purposes during the training process. Without a doubt, it’s a necessary component of a training program. However, to be properly implemented in the training, a Maximum Oxygen Intake test has to precede. 

The test will be performed and analyzed by a specialized occupational egophysiologist, who will measure and record all the necessary data regarding the athlete’s fitness status. Afterward, the coach can create a personalized training plan for their athlete that matches their profile; and, of course, guide them towards achieving the maximum possible performance in their sport.

Threshold Running: All you need to know about it was last modified: November 12th, 2021 by ScienceTraining