Sleep vs. Exercise: Which Is More Important for Managing Stress?

Author: Adam Meyer; Reviewed by Dietitian Jessica Ball, M.S., RD

When stress reaches a breaking point, you’re often told to get more sleep and move your body more. Both strategies are well-supported by research, but when you’re already stretched thin, it can feel daunting to figure out where to focus first.¹ The answer depends on what your body is dealing with at any given moment. Sleep and exercise both affect your hormones, nervous system, and brain chemistry, which influence how you experience and recover from stress.¹ But they do it in different ways, and understanding those differences can help you make better choices for your mental and physical health.

To break it down, we spoke with experts about how sleep and exercise each help manage stress, how they work together, and what to prioritize when you can only focus on one.

Benefits of Sleep

It Regulates Your Stress Hormones

Cortisol, your body’s main stress hormone, follows a natural daily rhythm: it’s lowest in the evening and highest in the early morning to help you wake up. When you consistently don’t get enough sleep, that rhythm can get disrupted, and your cortisol levels can stay elevated when they should be falling, leaving you in a state of low-grade physiological stress before the day even begins.²

Research shows that chronic lack of sleep is associated with significantly increased mortality and chronic disease risk.³ “Getting less than six to seven hours [of sleep] can significantly increase mortality and disease risk,” says board-certified physician and sleep expert Alex Dimitriu, M.D.

It Can Strengthen Emotional Resilience

According to a 2022 study, sleep deprivation can heighten your emotional reactivity and weaken prefrontal circuits involved in emotion regulation and impulse control, which can make stress feel more intense and challenging to manage.⁴

“Sleep loss further weakens the prefrontal cortex’s ability to control emotional reactivity, amplifying stress responses by up to 60%,” explains Dimitriu. So what feels like a manageable frustration on a well-rested day can feel overwhelming after a poor night’s sleep, not because the situation changed, but because your brain’s stress-regulation capacity did.

It Activates Your Body’s Recovery Mode

Sleep is when your parasympathetic nervous system, often called the “rest and digest” branch, takes over. This overnight shift is one of the main ways your body practices downshifting out of the heightened “fight-or-flight” mode. Without enough quality sleep, your nervous system may struggle to make that transition the following day, keeping you stuck in a low-level stress state.⁵

This is also when your brain consolidates memories, clears metabolic waste, and resets emotional tone. Losing even one or two hours of sleep regularly can disrupt these processes, making it harder to cope with everyday stressors.⁶

Benefits of Exercise

It Gives Stress Somewhere to Go

Stress triggers a physiological response, including a raised heart rate, increased cortisol and adrenaline levels, and muscle tension. When all that stored energy has nowhere to go, it cycles through your body and mind, potentially contributing to feelings of overwhelm. Fortunately, regular exercise provides a physical outlet for that built-up tension.⁷

Light physical activity, such as a short walk, a stretching session, or a bike ride, can help lower stress hormones and encourage your body to return to a calmer baseline. “Exercise acts as a ‘blow-off valve’ to reduce these levels and calm the nervous system,” explains Dimitriu.⁸

It Builds Long-Term Stress Resilience

Aerobic exercise (e.g., brisk walking, jogging, swimming, cycling) trains your body how to ramp up under pressure and recover efficiently. Your cardiovascular recovery rate, which is how quickly your heart rate and stress hormones return to baseline after exertion, tends to improve with regular exercise.⁹

Research suggests that adding just 10 minutes of moderate physical activity daily could prevent more than 100,000 deaths each year among U.S. adults ages 40 and older, a figure that shows just how well exercise can protect your body against the negative effects of chronic stress.¹⁰

It Supports Mood & Brain Health

Exercise has been shown to increase the production of endorphins and serotonin, two neurotransmitters that support mood regulation and reduce symptoms of anxiety and depression.¹¹

Moving your body regularly also stimulates the production of brain-derived neurotrophic factor (BDNF), a protein that supports the formation of new neural connections and is closely linked to a steadier, more resilient stress response.¹²

“For sedentary individuals, exercise is essential to regulate mood and improve the quality of the sleep they are getting,” says Dimitriu.

Which Is More Important?

If you regularly don’t get enough sleep, adding in intense exercise may leave you feeling even more depleted, irritable, and too wired to settle at bedtime. In that case, prioritizing good sleep habits like a consistent wake time, morning light exposure, cutting caffeine in the afternoon, and an evening wind-down routine is the more effective first step.

“Sleep is always the most important factor,” says Dimitriu. “It is the foundation upon which everything else stands.” However, if you’re mostly sedentary and sleep isn’t an issue, focusing on your exercise routine may be the better starting point. “Even a short walk in nature can help calm an active mind and make it easier to sleep better,” says Dimitriu.

The good news is that you don’t have to choose between them for long. “Sleep and exercise reinforce each other in a virtuous cycle,” explains Dimitriu. “Getting good sleep increases your chances of hitting physical activity targets, while regular exercise improves sleep depth and quality.”

Studies show that getting at least seven hours of sleep, combined with regular exercise, is associated with the best health outcomes. Ultimately, better sleep makes exercise easier to stick with, and regular exercise makes sleep more restorative.¹³

“You need to sleep and move for optimal health,” says Amy Gutman, M.D., FACEP. “Sleep restores the body’s stress-response system; exercise trains it to become more resilient.”

Our Expert Take

When it comes to managing stress, sleep and exercise are two sides of the same coin. Getting enough sleep helps regulate stress hormones, improve emotional resilience, and support recovery, while regular exercise helps alleviate stress, build long-term resilience, and enhance mental health and brain function. If you’re sleep-deprived, that’s where to focus your attention first. If you’re mostly sedentary, even a short daily walk can help improve your health. Speak with a health care provider before starting a new exercise routine or if you have questions about how sleep and exercise are affecting your health.

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