Living a largely stagnant life, sitting all day, or quitting or drastically reducing your training program won’t just hurt your body. It’s been proven that your brain will suffer, too. Regular exercise has been proven to help fight these five negative physical and mental side effects late into life. 

From mood dives to brain aging, your brain's gray matter — where all of the processing is done — works best when you've put yourself through a workout. That’s because exercise doesn’t just strengthen your heart and muscles, it strengthens your brain tissue, too, and helps stimulate the health and growth of new brain cells.

So if you've been slacking off, consider these five adverse effects on your cognitive abilities that occur when you quit or cut back on your training.

What Are the Effects of Quitting on Your Brain?

1. Decreased Mood

One of the most noticeable unfavorable outcomes of giving up exercise is the negative impact it has on your mood. Exercise helps pump up the production of the brain’s feel-good neurotransmitters such as serotonin, dopamine, norepinephrine, and endocannabinoids (the “don’t worry, be happy” chemicals similar to those found in cannabis). Low levels of these chemicals in your brain can make you more prone to symptoms of depression, as well as other mood or memory disorders.

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A Psychosomatic Medicine study revealed that when 40 routine exercisers were deprived of their regular workouts, they displayed much higher symptoms of fatigue, depression, and anger than those participants who consistently continued with their training — and that was just after two weeks.

2. Faulty Memory

Alongside plummeting positive moods and energy levels, ditching your workouts can be dangerous for your memory.

Science shows that regular exercise expands the volume of the hippocampus, which plays a key part in the brain’s memory functions. The more frequently you work out, the greater the blood flow to that part of your brain. The flip side of that is that when you quit training, the blood flow to the hippocampus decreases. This has even been linked to mild cognitive impairment and Alzheimer's disease.

And of course, exercise also has an indirect effect on memory, as regular workouts can help improve sleep, which is a known contributor to better cognitive functions.

3. Inability to Process Information

One of the most interesting benefits of exercise is that it can make you a better thinker. Along with memory enhancement, taking your training seriously helps with focus, decision-making, and the ability to process information. This is because high levels of physical exercise help increase cortical thickness in the prefrontal cortex (the part of the brain linked to executive functioning). The more you train, the more that you increase the growth of new blood vessels along with blood supply to this region of the brain.

Related: This Is the One Rule That the Most Mentally Tough People Live By

Though it really doesn’t matter when you train, one study carried out by researchers from the University of Western Australia (UWA) did discover that as little as 30 minutes of moderate-intensity aerobic exercise in the morning improved the cognitive abilities associated with executive functioning.

4. A Prematurely Aging Mind

Our brains boast a team of resident cells called microglia, whose job is to maintain immunity, regulate brain development, and root out any brain-related problems that they find. 

As we age, though, our microglia becomes less efficient at clearing away damaged cells, microbes, and other dangers to our brain functions. This means that memory can become foggy, thinking can become less clear, and — in more severe cases — we can become more susceptible to degenerative conditions such as multiple sclerosis and Alzheimer’s disease.

But recent studies have shown that exercise can actually “reprogram” these microglia in an aging brain to not only reinforce their immune-boosting capabilities, but to make the brain sharper overall.

5. Deteriorating Overall Brain Health

A final (but fundamental) reason to never quit exercising is that continuous training can increase your Brain-Derived Neurotropic Factor (BDNF) levels.

BDNF is a protein that plays a crucial role in the survival and growth of neurons, the messengers of the nervous system. As a result, it’s associated with slower cognitive decline.

Related: Does Quitting Make You Quit Again? A Neurosurgeon Explains

This beneficial protein helps regulate synaptic plasticity, which is essential for learning, long-term memory, and adapting from experience. It’s also thought to play a role in reducing depression-like symptoms, and is found in areas of the brain that are related to the control of eating, drinking, and body weight.

Studies have suggested that both aerobic and anaerobic exercise are effective at increasing BDNF levels. Not only that, but the effects are realized immediately. While, of course, you’ll get better, longer-lasting results if you work out regularly, this proves that — even if you’ve never trained before — there’s no time like the present to start.