Updated: Dec 1, 2021
The sad fact about addiction treatment in the US is that, according to the National Institute on Drug Abuse (NIDA), the first year relapse rate is 40-60%. Common approaches to treatment include medication and various types of behavioral therapy - CBT, Motivational Enhancement Therapy, Family Therapy, 12-Step programs and more. These are all effective tools, backed by years of experience and evidence in the medical literature. Yet, despite the use of these well-vetted tools, first year post-treatment relapse rates are still high.
What is missing?
Drug dependence produces significant and lasting changes in brain chemistry and function, yet the traditional therapies don’t attempt to reverse these changes. These therapies offer clients the skills, insights and knowledge to begin life in recovery; but they don’t help clients develop the brains which are needed to implement these tools.
People often leave treatment with brains that are too structurally, functionally, and chemically impaired by their substance misuse to support the learning and memory needed to practice new habits and build a new life.
Changes in the Brain
Decreased Dopamine Receptor Availability
Dopamine is a neurotransmitter which rewards life-sustaining positive behaviors such as eating, keeping warm, reproducing, and connecting with others. Dopamine is released as one anticipates these behaviors as well as when these behaviors are performed.
For example, imagine you are hungry, and you smell your favorite food. You are already feeling joyful at the thought of eating it, because you remember how good it tastes and how satisfying your meal will be. This feeling persists even after you eat your meal. Dopamine was released when you anticipated eating, and more was released when you satisfied your hunger. As this dopamine is absorbed by dopamine receptors; the memory that eating is positive is reinforced.
Substance misuse disrupts this normal process because the increases in dopamine levels associated with substance misuse are so much greater than those associated with life-sustaining and common pleasurable activities. Eating raises dopamine levels by roughly 50% whereas amphetamines can increase dopamine levels by 1000% to 10x the normal levels.
These dopamine spikes teach the brain that using is far more important than normal life-sustaining behaviors. Therefore, people misusing addictive substances begin making decisions that favor substance use over all else.
These spikes also cause structural and functional problems that take a long time to reverse themselves if not addressed directly. First, as the dopamine floods the brain, it overwhelms the dopamine receptors. Over time, these receptors begin shutting down. Thus, people need to use more heavily to achieve the same high.
Eventually, there are so few available dopamine receptors that individuals who have become heavy users rarely if ever feel pleasure. Stopping makes one feel even worse. Sobriety may not feel worth it.
Dysfunctional Neural Connections
As the brain learns that substance use is more important than most other behaviors, neurons begin to form new connections to support this behavior. A network of dysfunctional connections makes seeking and using addictive substances a nearly automatic response to life’s pain and challenges.
With each additional exposure to the addictive substance, these neural pathways grow stronger. An individual may leave treatment with the knowledge of new habits, but with a brain that is wired to prefer old habits.
Dopamine spikes not only contribute to decreased receptor availability and dysfunctional neural connections; they also contribute to a cascade of other neurochemical imbalances.
These imbalances are experienced as impulsiveness, depression, a desire to isolate, sleep disturbances, difficulty managing stress, poor decision-making, and so on. It is not a coincidence that these states are also common triggers for relapse.
Fortunately, depending on the severity and length of use, these structural, functional, and neurochemical changes can be significantly or even completely reversed. There are essentially two ways this repair happens – the slow way and the fast way.
The slow way is to patiently rely on the passage of time. Over time, dopamine receptor availability increases; new neurons grow and connect; and brain chemistry stabilizes. Clients regain the ability to experience joy from ordinary life activities. New healthy habits are reinforced as the new neural connections are used more frequently. As neurochemical rebalancing begins, the client’s emotional and mental state begins to improve. Behavior becomes less impulsive. Mental focus increases. Insomnia decreases. The mood lifts. Stress becomes easier to manage.
Unfortunately, this process can take months or even years. During this time of early brain rebuilding and neurochemical rebalancing, the risk of relapse is high. Clients have the skills and knowledge to create a rewarding life in sobriety; but they don’t yet have the brain structure, function or chemistry to reinforce this lifestyle.
Wouldn’t it be great if we could offer clients a tool to speed up the much needed brain restoration and rebalancing? Wouldn’t it be even better if the solution were low budget and simple? Such a solution exists. Evidence in the medical literature demonstrates that regular moderate aerobic exercise increases dopamine receptor availability, increases hippocampal neurogenesis and neuroplasticity, and promotes healthier brain chemistry.
Increased Dopamine Receptor Availability
In a study conducted at UCLA, former methamphetamine users enrolled in a residential treatment program were split into two groups. Both groups continued with the standard course of treatment (i.e., individual therapy, group therapy, 12 step meetings, etc.) Before the study began, PET scans were used to measure the baseline dopamine receptor availability for each participant. For the next 8 weeks, the first group was offered health education in addition to the standard therapy (individual and group sessions, 12 step groups).
The second group also received the standard therapy, but instead of the health education, they exercised for an hour a day, 3 times/week. The exercise included a warm-up, 30 minutes of moderate aerobic activity (jogging or stationary bicycle), weight training, and a cool down.
At the end of 8 weeks, PET scans were taken again. The Education group saw an increase of striatal dopamine receptor availability of only 3.13% while the Exercise group saw an increase of 13.89%. In other words, 8 weeks of regular moderate aerobic exercise increased dopamine receptor availability more than 4 times faster. To the client, results are experienced as more joy from normal life activities, improved decision making, and less impulsivity.
Increased hippocampal neurogenesis (new neuron growth) and neuroplasticity (formation of new connections among neurons)
The hippocampus is the part of the brain responsible for learning and memory, among other functions. Thus, increases in the rate of new cell growth (neurogenesis) and the development of new connections (neuroplasticity) promote faster learning while improving memory more quickly. It has been well documented that exercise increases production of BDNF (Brain Derived Neurotrophic Factor), the chemical responsible for stimulating this brain cell growth and connectivity.
In a study conducted at a Finnish university, researchers wanted to know which type of exercise promoted the most growth. The four groups for the 8 week study were (1) moderate aerobic exercise, with rats allowed to run on wheels in their cages (2) high intensity interval training (HIIT), rats forced to run on treadmills programmed to change speed (3) weight lifting, rats forced to climb ladders while pulling up weights strapped to their tails and (4) the sedentary control group.
Compared to sedentary animals, the rats that ran voluntarily on a running wheel had 2-3 times more new hippocampal neurons at the end of the experiment. Resistance training had no such effect, and the effects of the HIIT were minimal. Per the researchers “only sustained aerobic exercise improved hippocampal neurogenesis”. Moderate aerobic exercise produces 2-3 times more of the brain cell growth and connectivity needed to learn and reinforce new habits.
The aforementioned improvements in brain structure and function happen over a matter of weeks, but there are also exercise-induced brain changes that happen within minutes of engaging in moderate aerobic exercise. The chemical imbalances triggered by the dopamine spikes can be resolved over time through exercise, and this moderate aerobic activity stimulates production of neurochemicals which create positive experiences almost immediately.
Among the most well-known effects of exercise is the increase in endorphin production. Endorphins bind to the same receptors as opioids and serve to reduce physical as well as emotional pain. Though often associated with runner’s high, newer research suggests that because the endorphin molecule is too large to pass through the blood brain barrier, the runner’s high is actually caused by anandamide, an endocannabinoid released in the brain during moderate aerobic exercise.
This form of activity also increases production of serotonin, an antidepressant, and oxytocin, the hormone associated with bonding and connection. In short, exercise boosts production of neurochemicals associated with reduced pain, inner peace, elevated mood, and bonding. Regular exercise helps make sobriety a more positive experience and teaches people that they have the power to improve their emotional state.
Prolonged substance misuse alters brain chemistry, structure, and function, making it difficult for clients to learn and embrace new habits and experience the joys of sobriety. Although brain health improves with abstinence, the process is slow. Thus, the newly sober often begin recovery with the knowledge and skills they need, but with a brain that is not healthy enough to support these new behaviors.
Exercise significantly increases the rate of brain repair by increasing dopamine receptor availability and promoting new brain cell growth and connectivity. Furthermore, it induces positive chemical changes which have an immediate effect on the client’s mental and emotional state. By encouraging our clients to include regular aerobic exercise in their self-care routine, we are empowering them to significantly reduce their risk of relapse.
Let Us Help You
Strides in Recovery is a nonprofit based in Los Angeles that brings goal-oriented group walking/running programs to addiction recovery communities (residential, PHP/IOP, outpatient, and community based groups). We make fitness fun and uplifting; and our recovery focused messaging helps participants translate experiences from training into life lessons that support long term recovery. To learn more about bringing a program to your community, email us at info@StridesInRecovery.org
A similar version of this article was first published on July 7, 2020 in RecoveryView.com