lactic acid or lactate
Lactic acid is produced mainly in muscle cells and in red blood cells. This acid is formed when the body breaks down carbohydrates to use for energy during times of low oxygen levels. The oxygen level in the body may drop during strenuous exercise or if the person has an infection or illness.
A test may be done to measure the amount of lactic acid in the blood.
Lactic acid is good for muscles
Anyone who has even thought about doing gymnastics has heard warnings about lactic acid. "It accumulates in the muscles." "It's what burns the muscles." “Its buildup is what makes muscles tired and damaged.” All this is wrong.
Lactic acid is actually a fuel, not a waste product. Muscles make it deliberately, from glucose, and burn it for energy. The reason athletes can push themselves so hard and for so long is that practice makes their muscles absorb lactic acid more efficiently.
Muscle cells convert glucose into glycogen or lactic acid. This is absorbed and used as fuel by the mitochondria, the energy factories of cells. Mitochondria even have a special protein to transport it inside.
Intense training makes a big difference because you can double the mass of your mitochondria and make your mitochondria burn more lactic acid and your muscles can work harder and longer.
Lactic acid and exercise
Lactic acid or lactate is an organic compound that occurs naturally in each person's body. In addition to being a by-product of exercise, it's also a fuel for it. It is found in muscles, blood, and various organs. The body needs it to function properly.
The primary source of lactate is the breakdown of a carbohydrate called glycogen.
Glycogen is broken down into a substance called pyruvate and during this process produces energy. We often refer to this process as anaerobic energy because it does not use oxygen.
When pyruvate breaks down further, it produces more energy. This energy is aerobic because this additional process uses oxygen. If pyruvate is not broken down, it is usually converted to lactate.
When pyruvate is produced, the muscle cell will try to use it for aerobic energy. However, if the cell does not have the capacity to use all the pyruvate produced, it will chemically convert to lactate.
Some cells have a high capacity to use pyruvate for aerobic energy while others have a low capacity. With training, many cells can adapt to use more pyruvate and therefore produce less lactate.
Lactate is present in our system at rest and as we go about our daily activities, although only at very low levels. However, when we increase the intensity of our exercise or work activities, large amounts of pyruvate are produced rapidly.
Because pyruvate can be rapidly produced, not all of it is used for aerobic energy. Excess pyruvate is converted to lactate. It is for this reason that lactate is such an important signal for training. When produced, it indicates that aerobic energy is limited during activity.
When exercise is increased, additional amounts of muscle fibers are recruited. These fibers are used infrequently during rest or light activities. Many of these fibers are "fast twitch" fibers. "Fast twitch" fibers don't have much of an ability to convert pyruvate into aerobic energy. Therefore, much of the pyruvate is converted to lactate.
Lactate is a very dynamic substance:
First , when lactate is produced, it tries to get out of the muscles and into other nearby muscles, into the bloodstream or into the space between muscle cells where there is a lower concentration of lactate. It may end up in another nearby muscle or somewhere else in the body.
Second , when lactate is accepted by another muscle, it will likely be converted back to pyruvate and used for aerobic energy. Training increases the enzymes that rapidly convert pyruvate to lactate and lactate to pyruvate.
Lactate can also be used by the heart for fuel or it can go to the liver and be converted back to glucose or glycogen. You can quickly travel from one part of the body to another. There is even evidence that some amounts of lactate are converted back to glycogen within the muscles.
Importance of lactate on the muscular system
When lactate is produced in the muscles, excessive hydrogen ions are produced along with the lactate. If there is a substantial buildup, the muscles become very acidic. These hydrogen ions cause problems with muscle contraction during exercise.
Athletes describe a "burning" or "squeezing" sensation in the muscles when exertion is extreme. When lactate is produced, hydrogen ion is produced; when lactate leaves the cell, hydrogen ions leave the cell with the lactate. Therefore, lactate is not the cause of muscle fatigue. But it is directly related to heartburn which is believed to be the real cause of it.
Although athletes don't like this burning sensation, it really is a defense mechanism against muscle damage. Too much acidity can break down muscle fiber. It is theorized that one of the causes of excessive training ("over-training") is too much training at levels that produce high levels of acid.
Athletes can either produce less lactate or clear lactate more quickly from their muscles, the process will reduce troublesome hydrogen ions that inhibit their performance.
Research in recent years has shown that while lower production is important, the key to athletic success is being able to clear lactate from the muscle where it is produced.
If the athlete trains well, his body will move or transport the lactate to another place quickly and solve the problem of having very high lactate levels in the muscles. This means that when an athlete competes at a high level he will be able to maintain high levels of effort for longer if his body clears the lactate quickly.
Second, for events that last less than 10 minutes (for example, swimming, rowing, track cycling, skating, and many running events), the ability to produce large amounts of energy toward the end of the event is critical for success. Blood lactate is an indication of how much energy has been generated. Therefore, one of the best ways to test whether an athlete has generated high energy levels towards the end of an event is to measure blood lactate levels after an all-out effort. The higher, the better.
Because lactate plays such an important role in energy production and athletic performance, sports physiologists and coaches have developed various ways to measure and monitor it.
The most common way to measure lactate is through a graded exercise test. For example, the athlete runs, swims, or rows at progressively faster speeds while the coach, coach, or sports physiologist measures the lactate level at each speed.Thank You