Why We Get Tired


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Everyone, at some point, hits a wall.

When you are focusing on a project or some task for a number of hours, you deplete the easily accessible stores of glucose that the body has at the ready. Glucose is a sugar that serves as a primary energy source for every cell in the body.

When easily accessible glucose reserves drop to a certain level, the brain sends you a signal to either rest, eat or engage in a habit.

Depending on which course of action you take, these diversionary tactics buy the body time to restore glucose levels. Once the glucose level is restored, your brain sends you a signal that it is OK to resume working on your project or task.

If you ignore your brain, it will punish you. Your cognitive ability will decline dramatically and you’ll find yourself making mistakes. Or worse, your brain will force you into a dreamlike alpha state, which is a precursor to sleep. Falling asleep, while driving a car, is an example of the brain shutting down due to glucose deprivation.

Whenever you find yourself hitting a wall while working, grab a healthy snack.  Apples, bananas, oranges, pineapples, cherries, avocados, raisins are all good glucose-packed snacks. If you eat carbs, such as bread (whole wheat or multi-grain = good carbs), just remember that carbs will require some additional processing (digestion) time before they are converted to glucose.

If you hit a wall, while exercising or while engaged in some physically demanding activity, such as a half marathon, tennis match, basketball game, etc., our amazing bodies have a solution that does not require you to stop. During vigorous activities, the body shifts to a ketogenic state.

When our muscles and livers run out of glycogen (glycogen is converted into glucose), the body must turn to fat. The fat is broken down and converted into ketones. Ketones are a superior fuel substitute for glucose. These ketones are then sent around the body, via our blood, to where they are most needed.

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Thomas C. Corley About Thomas C. Corley

Tom Corley is a bestselling author, speaker, and media contributor for Business Insider, CNBC and a few other national media outlets.

His Rich Habits research has been read, viewed or heard by over 50 million people in 25 countries around the world.

Besides being an author, Tom is also a CPA, CFP, holds a master’s degree in taxation and is President of Cerefice and Company, a CPA firm in New Jersey.
Phone Number: 732-382-3800 Ext. 103.
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  1. Tony McDonald says:

    Good one Tom and so true. I am an ex-military guy (West Point) and if the military teaches you anything its that you can do more than you think – especially when someone unpleasant and demanding pushes you to do it! That’s how we stretch and grow.

    • Thank you for your service Tony and thank you for your kind words. Growth is never comfortable. Those pursuing daily growth are the most humble people around because they are constantly pushing themselves outside their comfort zone and that is humbling.

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