Spark: The Revolutionary New Science of Exercise and the Brain

by John J. Ratey

If you get your body in shape, your mind will follow.

I focus on getting fit because we know with certainty that having a normal body mass index and a robust cardiovascular system optimizes your brain.

if you’re going to bother doing something for your brain, you might as well do enough to protect your body against heart disease, diabetes, cancer, and the like.

human species as an endurance predator.

even after ranging miles over the landscape we retain the metabolic capacity to sprint in short bursts to make the kill.

Your choices aren’t limited to these modes of aerobic activity, naturally, but I think they’re helpful categories to distinguish between low-intensity (walking), moderate-intensity (jogging), and high-intensity (running) exercise.

I’m referring specifically to exercising at 55 to 65 percent of your maximum heart rate.

moderate intensity falls in the range of 65 to 75

high intensity is 75 to 9...

The best, however, based on everything I’ve read and seen, would be to do some form of aerobic activity six days a week, for forty-five minutes to an hour. Four of those days should be on the longer side, at moderate intensity, and two on the shorter side, at high intensity.

For some people it’s a catch-22: they can’t start because they don’t have the energy, and they don’t have the energy because they’re not exercising.

the neurological benefits I have described are greater when exercising with someone else.

They don’t know how long the effect lasts, but the findings underscore how even a minor amount of activity sparks a positive domino effect.

Walking will make you feel more invested in the world around you. Before long, you’ll want to get out there even more.

how far they can walk in six minutes.

you might be pleasantly surprised at how quickly you begin to cover more ground.

Once you work up to an hour at a pace just above where you can carry on a conversation, you’re ready to add in moderate-intensity exercise.

Once you move into moderate-intensity activity, between 65 and 75 percent of your maximum heart rate, your body shifts from burning fat alone to also burning glucose, and the muscle tissue develops microtears as a result of the stress.

BDNF is the best defense for your neurons. By elevating restorative chemicals with a moderate workout, you’re strengthening the circuits in your brain and tuning up the HPA axis so that it isn’t as trigger-happy to future incidents of stress.

atrial natriuretic peptide (ANP).

ANP travels through the bloodstream and into the brain, where it helps to further moderate the stress response and reduce noise in the brain.

cascade of chemicals that relieve emotional stress an...

helps explain why you feel relaxed and calm after a modera...

At high intensity, between 75 and 90 percent of your maximum heart rate, your body enters into a full-fledged state of emergency, and its response is appropriately powerful.

metabolism shifts from aerobic to anaerobic, in which your muscles go into a state of hypoxia because they can’t pull enough oxygen from the bloodstream.

your muscles begin to burn creatine and glycogen stored directly ...

you want to be flirting with that thigh burn (after warming up) but staying just below it throughout your run.

One of the key differences between moderate and high-intensity exercise is that once you get closer to your maximum, and especially when you get

into the anaerobic range, the pituitary gland in your brain unleashes human growth hormone (HGH).

the fountain o...

that by middle age they dwindle to a tenth of what they were during childhood,...

HGH is the body’s master craftsman, burning belly fat, layering on muscle fiber, and pumping up brain volume. Researchers believe it can reverse the loss of brain volume that naturally occurs as you age.

buildup of fast-twitch muscle fibers, which adds power to their movements.

By going beyond where you thought you could, straining and stressing and lingering in that pain for even just a minute or two, you sometimes transcend into a rarefied state of mind, in which you feel like you can conquer any challenge.

The euphoric feeling is likely due to the mixture of extremely high levels of endorphins, ANP, endocannabinoids, and neurotransmitters pumping through your system at this intensity.

interval training improves learning ability.

the sprinters learned vocabulary words 20 percent faster.

even a small dose of pushing yourself to the limit has profound effects on your brain.

You really need to have a rock-solid aerobic base and talk to your doctor about what you’re planning.

you should have at least six months of six-days-a-week aerobic activity before mixing in interval training.

The results we do have on nonaerobic exercise aren’t as robust as those for aerobic exercise.

A very recent study among older adults found that lifting weights twice a week for six months made participants stronger and actually reversed aspects of the aging process at the genetic level.

Most of the brain research on resistance training has focused not on learning and memory, but on mood and anxiety.

the results remained for a year regardless of continued exercise levels.

I’m sure that as neuroscientists delve deeper into the brain they’ll discover pathways that connect the dots.

half of those

who start up a new exercise routine drop out within six months to a year.

you feel lousy even at lower intensity levels, don’t take on interval training in the early stages of your new routine.

you may be genetically predisposed to dislike it.

all of us can rewire our brains by taking action.