The Lactic Acid Myth - Busted!

"Feel the burn!" The lactic acid myth revealed!

You hear it all the time in the gym when you feel that burn in the muscle. "Oh that is the lactic acid building up in your muscle. That is why it burns." Is that really what is happening or is there some other chemical or physiological explanation for the burn you feel. You have probably been sore a day or two after a good workout. Again, some attribute this to lactic acid build up. Can there be another explanation for this?

Yes! The idea that lactic acid is the cause of such discomfort is not supported by basic biochemistry, the chemical reactions that take place in your body. It is true that lactic acid exists. However, lactic acid is not the cause of the soreness or the burn.

Maybe a quick summary of basic chemistry will help. Acids are made up of a “free” hydrogen molecule (not chemically combined with another substance) and a salt molecule such as lactate. Under the right conditions, these two molecules chemically combine to form an acid. One of the most common acids is hydrochloric acid. The number of hydrogen molecules that are “free” determines the pH of a solution. The measure of the concentration of free hydrogens in a solution is known as pH. A lower pH value means that the solution or environment has a greater concentration of free hydrogens (more acidic). A higher pH value means that the solution has a lower concentration of free hydrogens. We call this basic or alkaline.

The value of pH is measured on a scale from 0 to 14. Stomach acid has a pH of around 2. Water has a pH of around 7 and liquid drain cleaner has a pH of around 14. When you combine a base and an acid, the solution moves closer to the neutral pH around 7. That is why you add baking soda to your pool if the pH is too low and muriatic acid if the pH is too low. By doing so you are providing a salt for the hydrogen to bond to thereby reducing the concentration of free hydrogens. This increases the pH

At a pH of 3.86 lactate bonds with free hydrogens to form lactic acid. However, when the pH is greater than 3.86 lactic acid becomes sodium lactate and does not contribute to the free hydrogens in the blood, which has a pH of around 7. Even during intense exercise the pH of blood does not drop very far below this. Therefore, lactic acid really does not exist in the body. In fact, the production of lactate in the blood during exercise helps to make the blood more basic and neutralize the pH.

The burn you feel during your workout is not a result of lactic acid. Nor is lactic acid the so-called “toxin” that is released when you get a massage. But that’s another story…

For more detailed information on the biochemistry involved please see the following article by Robert A Robergs:
Exercise-Induced Metabolic Acidosis: Where do the Protons come from?

Interval Training

What is Interval Training?

The term "interval training" has become quiet the buzz word over the past year. So what is it and how does it work? First off, interval training is not a new technique for athletic performance improvement. Athletes have made interval training a part of their training for many years. Fartlek training is a good example of a training technique based on the same principles. Interval training is simply combining periods of high intesity exercise with low intensity exercise. You can apply interval training no matter what your level of fitness.

Many studies indicate that the use of interval training with "untrained" individuals is more effective at decreasing a person body fat than long slow distance training like most people are used to doing. They also got in shape faster. Here is a personal example. Several years ago I was looking to supplement my income a little and decided that I would deliver newspapers in the early morning. Well, instead of driving my car to each individual house, getting out. letting the engine run, and move on, I decided I would park my car, grab as many papers as I could carry and run from one house to the next. I would then get in the car and drive to the next area. This short duration, high intensity exercise with rest in between is what interval training is all about. Within 3 or 4 weeks I noticed that my pants were a little loose and I wasn't quiete as out of breath coming back to the car.

So how does it work? Think of your body as having 3 different types of fuel, or energy systems, to use. I will use the metaphor of starting a fire to help illustrate. The first fuel is easily ignited and burns really quickly (think of a match). The second fuel takes a little more effort to get it going but will burn for a little longer than the first (think of the kindling). The third energy system takes quiete a bit of effort to get started and burns really slow and long (think of the oak log). Each of these systems has fancy scientific names attached to them. Maybe in another blog I will go into further detail.

When you are doing interval training you are burning matches like crazy and some of the kindling, depending on how long your exercise bout is. During your recovery period, which could last up to 3x the length of your exercise bout, your body uses energy from the oak log to rebuild your matches. The oak log uses fat for energy and to replace the energy used during the match phase and the kindling phase.

By using high intensity interval training you are training your body to use fat to replenish your emergency fuel sources.