energy stores

During my long run ( 8 miles this week) my personal training textbook kept popping into my head.  I kept thinking about lactate threshold and how and why we train the way we do for an event.


slow twitch, fast twitct, lactid acid, lactic threhold.
We have all heard them but what do they mean?

Let's start with muscles fiber types known as type I   . Type I are your slow twitch muscles which means these are the muscles that are selected for low intensity and long duration and are often referred to as "aerobic" because of the ongoing oxidation. This oxidation is fueled by carbohydrates and fats already in your system. These are the muscles that we use for running, swimming and cycling.

Type II muscles are the muscles used for high intensity speed tasks and power.
Those who have more success in speed in power have a great percentage of fast twitch muscles distributed through the major muscles groups.  Fast twitch muscles are considered anaerobic because they rely on energy sources within the muscle not the fuels used by type I.  Think weight lifting and boxing drills along with plyometrics.

Lactic acid is commonly associated with the pain felt in the muscles after a workout.
When energy is required to perform and exercise, the body uses the stores of glycogen in your fast twicthc muscles first, this lasts 3-5 seconds, after that there is a chemical reaction ithin the muscles known as anaerobic glycolysis. This is sustained through resynthesis from a large amount of energy which relies on on respitory and cardiovascular system for the delivery of oxygen which in turn helps remove waste production and help deliver nutrients.
I have a link here if you interested in reading the more technical version of lactic acid.

So my point in discussing all of this is to educate you in how your muscles work and the fuel that it needs to get through not only a day but a strenuous exercise.    When you muscles get used to producing "x" amount of energy you can push them through to the next level by breaking the lactate threshold ,working through the "burn".

you need fast twitch muscles for your initial start of exercise, to push you into it, after a few seconds your slow twitch muscles kick in and finish out the exercise, while you exercise you build lactate in you muscles to make the grow.

This is probably the least sexy but probably the most important thing i can share with you. By understanding how your muscles draw energy it allows you to fuel your body properyly which ultimately takes us back to diet, not the diet you are on to lose weight but your real diet. Eating a candy bar is providing immediate sugar to the blood stream which is quickly broken down and stored . whatever the body cannot use its stores as fat for another time. On the other hand eating some protein and vegetable, the body breaks them down and uses them right away. This is a subject I can spend hours explaining and discussing but i hope i provided a little insight in energy stores.

Play hard!
Laura