How to differentiate and calculate aerobic and anaerobic thresholds

In running, it is common to calculate the aerobic and anaerobic thresholds when defining training sessions that are as effective as possible, as well as personalized for each individual and their actual physical capacities.
When someone starts to take an interest in running, existing tables are usually used to start running from scratch or to achieve relatively simple goals like completing a 5 km route. In these types of cases, and provided a doctor approves, general guidelines are sufficient. However, once running becomes a habit or there are more specific goals, it is necessary to adapt routines and, to do so, establish the individual’s capacity and endurance.
The most efficient method to obtain these values is a stress test including gas exchange analysis monitored by a cardiologist. This data in the hands of a training professional will do the rest.

What is the difference between one threshold and the other

When performing low-intensity exercise, between mild and moderate, the body will be able to generate all the energy it needs to carry it out, burning fats and carbohydrates for this purpose with the help of oxygen. In other words, the aerobic threshold burns fat more effectively, and that is why it is attractive to know how to stay within the limits that define it if that is the purpose of the exercise.
The moment the intensity of the sport increases, the system collapses, oxygen does not arrive fast enough, and the body must resort to its plan B to obtain energy with the urgency it needs. In this new process, more fuel will be needed to obtain energy, but oxygen will not be involved and lactic acid will be produced in greater quantities, producing a fatiguing effect on the muscle. All of this defines the anaerobic threshold.

What the VT1 and VT2 thresholds indicate

The VT1 and VT2 thresholds, or ventilatory thresholds 1 and 2 respectively, are different ways of naming the two previously mentioned processes. In this case, these are the terms used in laboratories or during stress tests, because the changes that occur between the use or non-use of oxygen in obtaining energy can be measured through breathing.
The VT1 would be equivalent to the aerobic threshold; moving from rest to moderate effort produces a slight increase in breathing, but this undergoes a change when the body begins to generate the lactic acid mentioned above, as the body eliminates it without problems through breathing. This change is easily observable during ventilation measurements and would define the start of the process.
When activity increases to the point of saturating the process of oxygen supply from the lungs, a new tangible change occurs that is reflected in breathing and indicates the shift from one threshold to another or the transition to the anaerobic (VT2).

How to calculate the aerobic and anaerobic threshold

To be able to calculate both points, it is necessary to know the maximum heart rate, and there is a fairly reliable formula:

207 – (0.7 x individual’s age) = MHR.

Calculating 75% of said maximum heart rate would yield the aerobic threshold, and the anaerobic threshold will be between 85% and 90%.