One of the main risks of practicing intense aerobic sports activities is that of exceeding the aerobic threshold, since the body will resort to anaerobic energy pathways for the production of the energy necessary to continue working. This can have serious drawbacks, as we explain below. Hence, the importance of working this threshold to increase its limit, avoid exceeding it and take advantage of its benefits. Below, we explain what the aerobic threshold is and why you should work it – in addition, of course, to how to improve the aerobic threshold with your indoor cycling bike or roller, among others. Read on!
What is the aerobic threshold?
The aerobic threshold, also known as ventilatory threshold (VT1), is one of the most important fitness indicators, especially for endurance athletes such as cyclists. It is used to guide training and optimize athletic performance, as well as to avoid the consequences of exceeding it. Specifically, it refers to the limit point during exercise at which the muscle begins to draw on the lactic acid system to supplement the aerobic system with more energy. In scientific terms this is known as the lowest intensity at which there is an increase in blood lactate concentration above normal resting values, which generally corresponds to lactate concentrations below 2 mmol/l – although it depends on the individual cyclist, as we shall see below. Lactate is a natural compound in the body that is produced as a result of the anaerobic metabolism of glucose, however its increase in the body can have serious drawbacks.
Why work the aerobic threshold
Increased lactate levels in the blood can have several negative consequences affecting muscle fatigue, decreased performance, altered blood pH, muscle soreness, limitations in training capacity and impact on recovery, plus in the worst case scenario, the blood can become too acidic and lead to a life-threatening condition of lactic acidosis. Working the aerobic threshold correctly will allow you to produce energy at lower intensity levels through aerobic metabolism (with oxygen) which will allow you to perform long duration activities without lactic acid build up. Training the aerobic threshold is ideal for developing endurance and is commonly recommended for endurance athletes, as with the aerobic threshold in cycling. Exercises in this intensity range can improve aerobic capacity, endurance and cardiovascular efficiency, which translates into improved athletic performance.
How to calculate the aerobic threshold
The first thing to make clear is that everyone’s aerobic threshold is different, and this depends on the individual fitness level and heart rate at threshold, so there is no specific optimal measurement. Generally, people with poor aerobic fitness have an aerobic threshold of 60% of their maximum heart rate, while trained athletes may be at 85% of their maximum heart rate. The aerobic threshold can be identified in several ways, the most advisable being stress tests in which the body’s response to different levels of exercise is measured progressively. This is the most reliable way to know it, although there are also exercise tests with masks that measure oxygen intake and the amount of CO2 in exhalation.
Thanks to them you can see when a significant increase in blood lactate begins to occur. For example, to help you determine if you are in your aerobic energy system and if you can sustain the effort you can get on your bike and see how long you are able to hold out at a moderate intensity. Generally, if you can’t sustain an effort for three minutes it is possible that your body has become anaerobic. The way to calculate the aerobic threshold is to subtract 30 beats per minute from the lactate threshold heart rate. This will give you a rough estimate of what your aerobic threshold is. Also, pay attention to your sensations and check if you perceive that the intensity of your training and effort is slightly above the resting level.
How to improve aerobic threshold
Cycling can be classified as an endurance sport, in which case the key is to be able to hold on as long as possible to go further. An improvement in the aerobic threshold translates into an increase in aerobic capacity and cardiovascular efficiency, improving athletic performance. Now, how do you work to improve the aerobic threshold? In cycling, exercises and interval work are very effective, especially when performed in controlled spaces, in which case it is easier to control resistance levels in the absence of external constraints. The most advisable is to work at home and for this you can use a special trainer, such as the smart ZDrive MAX model, which offers the most realistic cycling sensations thanks to its direct transmission and an optimized design with the latest generation of low cadence braking capacity.
After defining the work zones and calculating the aerobic threshold, as explained in the previous point, you can carry out specific training to improve it, such as the one described below:
- Warm up: 15 minutes on flat terrain, maintaining an intensity between 55% and 65% of our FTP.
- Main work: 2 sets of 20 minutes on even ground, working at an intensity between 76% and 88% of our FTP, with a cadence close to 75 rpm. Rest between sets will be 10 minutes, keeping the intensity below 55% of FTP.
- Cool down: 15 minutes on flat terrain, with an intensity between 55% and 65% of our FTP.