Chemicals located and released in the brain to allow an impulse from one nerve cell to pass to another nerve cell.


Lack of these hormones is associated with depression.  Stress and chronic depression have shown to shrink certain areas of the brain!  (See Stress, Depression in chapter 5)

Exercise aids in the production of BDNF (Brain derived neurotropic factor). BDNF is a crucial biological link between thought, emotion and movement.  BDNF is important for survival of neurons but also for their growth and thus for LEARNING!

BDNF sprinkled onto neurons caused them to sprout new branches automatically, thereby producing the same structural growth required for learning. It’s “Miracle-Gro” for the Brain!

“Physical movement and exercise is the basis for learning.  How much knowledge you retain depends a lot upon a proper balance of neurochemicals and growth factors to bind neurons together.  Exercise has documented dramatic effect on these essential ingredients”. – Ratey

Exercise Boosts Brain Power 

Exercise helps increase circulation, improves coordination and helps prevent conditions such as heart disease, stroke and diabetes, which increases the risk of developing dementia.  Exercise may increase the number of capillaries which help new cells grow.

Exercise stimulates patterns of neural activity that create more connections between different brain areas and cause nerve cells to produce natural brain nutrients or“neurotropins.” (Neurotropins increase the size and complexity of nerve cell dendrites, Duke University Medical Center, pp. 140-141)

Arthur Kramer, PhD; a researcher from the Univ. of Illinois; used MRIs to show that exercise actually makes your hippocampus (the area of the brain which forms memory) bigger.

In a study by Ratey (2008), an EEG showed more activity in “Fit” Kids’ brains, indicating that more neurons involved in attention were being recuperated for a given task. Ratey also showed that when information is received and practiced, it is processed and stored in the brain more quickly.

In a study conducted at the University of Illinois, it was found that cardiovascular fitness is associated with the sparing of brain tissue in aging humans. Furthermore, these results suggest a strong biological basis for the role of aerobic fitness in maintaining and enhancing central nervous system health and cognitive functioning in older adults.

Some early research suggests that aerobic exercise just twice a week halves one’s risk of general dementia and cuts the risk of Alzheimer’s by 60%.