What is it?
You keep hearing about this type of training, but what does it mean and why is it important?
To put it simply, its magic. Training in the aerobic heart rate zone causes the physiologic changes to the body that allow for increased athletic performance.
Basically, aerobic training means “in the presence of oxygen.” Activity in an aerobic heart rate zone allows the body to cycle through physiologic systems to generate essentially unlimited energy, assuming proper nutrition, during activity in the aerobic zone.
There are three energy producing systems utilized in the aerobic zone: aerobic glycolysis (slow), Krebs cycle (citric acid) and the electron transport train. These energy producing processes take place in the cells mitochondria and produce ATP. ATP is the fuel of the body; it is the substance that enables muscles to contract over and over again. As long as ATP is present the body can keep moving.
Cellular respiration can be an anaerobic or aerobic respiration, depending on whether or not oxygen is present. Anaerobic respiration makes a total of 2 ATP. Aerobic respiration is much more efficient and can produce up to 38 ATP with a single molecule of glucose, which is created when the food we consume is broken down and converted into glucose. A diet of simple carbohydrates during activity allows glucose to quickly enter the energy production system in the mitochondria to produce ATP.
This process to create 38 ATP from glucose is slow and requires oxygen, but this can essentially allow us to be able to perform low intensity activities for such long periods of time, as opposed to anaerobic training, where oxygen is not present.
How do I train the aerobic system?
Interval training (1-part work: 1-part rest, or 1:2), Fartlek training, or continuous training. Which brings us back to heart rate. Monitoring one’s heart rate throughout exercise will help one to maintain aerobic training.
Your optimal heart rate for aerobic training can be estimated through a simple formula: 220bpm – your age x 60%. A heart rate monitor is very helpful to be able to quickly adapt training effort to adjust to stay in the aerobic zone.
When you train in the aerobic zone many adaptations occur in the body that enhance athletic performance. One adaptation is mitochondria production, which is increased in the cells by at least 40%. This is good because the more mitochondria present in the cells, the more fuel the body can produce.
The body also begins to increase the ability to bring fuel to the cells, while removing waste through the process of capillarization, (the process of creating new capillaries.) The increase in capillaries brings more glucose to the mitochondria for increased ATP production and also allows for increased blood for cellular repair, and improved removal of waste which leads to reduced recovery time.
The hidden super power of humans is the ability to perform incredible endurance events. When the demand (energy required) is less than the supply (ability to produce) the athletic effort can be sustained. With appropriate training, and adequate nutrition during an event, aerobic effort can be sustained. If the production of energy falls short of the body’s demand, failure occurs. During the inaugural women’s marathon in the summer Olympics in Los Angeles Gabriela Anderson-Sohies demonstrated failure of this system. Gabriela had been appropriately trained, but admits that during the race she did not properly hydrate and fuel. In her final lap you can see the failure of her glute muscles, which led to her inability to stabilize her knees, and increasing difficulty to walk straight and even stand. Gabriela’s glute failure is noticeable from 3:10 to 3:20
During the process of creating ATP to fuel the body the byproduct is hydrogen ion which is converted to Lactate to reduce the acidity in the cell. Lactate is created when a substance called Pyruvate binds with the hydrogen ion in the cells to prevent cell failure. That excessive hydrogen ion in the cells, which increases the cell acidity, is the “burn” that is felt. With continued intense activity, the lactate can’t be created fast enough, and the cell environment becomes acidic, affecting its ability to function and resulting in muscle failure. High intensity activity rapidly increases the hydrogen ion, this is generally called anaerobic training. With increased aerobic training the body is able to convert 75-80% of the Lactate into fuel via the liver and re-enter the mitochondria to generate ATP.
When the system is not well trained or the effort exceeds the aerobic process and enter the anaerobic process the removal of the lactate can no longer keep up with production and the source of fuel is depleted performance will begin to decline.
4-6 sessions a week of 40-60 min in the aerobic zone, or 4-6 all out 30 second sprints will to help increase cellular mitochondria numbers. If you are incorporating strength training, it should come before your running, so you can rest afterward. Or run in the morning, and do strength training in the late afternoon.
Training with a ratio of 1:6 (for example 1-minute training work, 6 minutes rest) will help the body to increase the growth of capillaries.
Some training can force the body to better deal with waste – using a 1:3 training you can teach the body to better clear the lactate.
There are some further methods for highly trained athletes which is using a 2:1 ratio, as it doesn’t allow for lactate clearance it will teach an athlete to learn to tolerate the acidic burn.
by Victoria Vinet