The Relationship Between Cardio and Better Sleep

8 March 2025

Have you ever had one of those nights where sleep feels completely out of reach? You toss and turn, stare at the ceiling, and pray for your brain to shut off. It’s frustrating, isn’t it? Well, what if I told you that your ticket to better sleep might just be lacing up your sneakers and hitting the pavement? Yep, cardio—whether it’s jogging, cycling, swimming, or dancing—could be the key to unlocking restful, rejuvenating sleep.

In this post, we’ll dive into how cardio exercises help improve sleep quality, the science behind it, and some tips to get the most out of your workouts. So, whether you’re a night owl struggling with insomnia or someone looking to wake up feeling more refreshed, stick around because this might change your bedtime routine forever.

The Science of Sleep and Exercise: What’s the Connection?

First off, let’s talk about sleep. Sleep isn’t just about closing your eyes and hoping for sweet dreams—it’s a series of highly complex processes that your body absolutely needs. Think of it as nature’s reset button. Sleep is when your brain files away memories, your muscles repair themselves, and your hormones rebalance. But here’s the catch: stress, anxiety, and even a sedentary lifestyle can throw off this delicate process.

Now, this is where cardio comes in. Cardio workouts get your heart pumping, your blood circulating, and your body producing feel-good chemicals like endorphins. These “happy hormones” do wonders for reducing stress and anxiety—two major sleep disruptors. Additionally, cardio helps regulate your circadian rhythm (aka your internal body clock), which is crucial for falling asleep and staying asleep.

Think of cardio as a natural sleep aid, minus the grogginess and side effects. Pretty cool, right?

How Cardio Impacts Sleep Quality

Alright, so cardio is good for sleep—got it. But what exactly does it do to improve your snooze time? Let’s break it down into bite-sized chunks:

1. Reduces Stress Levels

Stress and sleep are like oil and water—they just don’t mix. When you’re stressed, your body produces more cortisol (the stress hormone). High levels of cortisol can keep you wired and make it nearly impossible to fall asleep. Cardio, however, acts as a stress-reduction powerhouse.

Even a brisk 30-minute walk can lower your cortisol levels and help your body relax. Ever notice how you feel less overwhelmed after a workout? That’s no coincidence—your body is actively fighting stress and prepping you for a good night’s rest.

2. Fights Insomnia

If you’ve ever struggled with insomnia, you know how draining it can be. The good news? Cardio can help. Regular aerobic exercise has been shown to reduce the time it takes to fall asleep and increase overall sleep duration. In fact, research from the American Academy of Sleep Medicine found that people who engaged in moderate-intensity cardio for just four days a week reported better sleep quality and fewer insomnia symptoms.

So, the next time you’re lying awake at 2 a.m., think about adding a cardio session to your daily routine.

3. Boosts Deep Sleep

Deep sleep—also known as slow-wave sleep—is the most restorative stage of the sleep cycle. This is when your body repairs tissues, builds bone and muscle, and strengthens your immune system. Cardio can actually help increase the amount of time you spend in this magical stage of sleep.

Why? Because cardio improves blood circulation and oxygen flow, which supports your body’s ability to recover during deep sleep. It’s like giving your body a performance-enhancing boost for its nighttime repair job.

4. Regulates Your Circadian Rhythm

Have you ever flown across time zones and felt completely out of whack? That’s your circadian rhythm being thrown off. But guess what can help tune it back up? Yep, cardio! When you exercise, your body temperature rises, and as it cools down post-workout, it signals to your brain that it’s time to rest.

Morning or afternoon cardio, in particular, can help reinforce your natural sleep-wake cycle. It’s like setting an internal alarm clock that tells your body when to get sleepy and when to wake up.

The Best Types of Cardio for Better Sleep

Alright, so we know cardio is awesome for sleep. But not all cardio is created equal. Here are some of the best activities to help you catch some quality Z’s:

1. Walking or Hiking

Think walking isn’t “real” cardio? Think again! A brisk walk, especially in the morning sunlight, is fantastic for regulating your body clock. Plus, walking is low-impact, so it’s easy on your joints—perfect for people of all fitness levels.

2. Running or Jogging

For the more adventurous, running can be an excellent sleep booster. It’s a great way to burn off extra energy, clear your mind, and reduce anxiety. Just make sure you’re not running too close to bedtime. The adrenaline rush might make it hard to wind down.

3. Cycling

Love the wind in your hair? Cycling is another great option for sleep-friendly cardio. Whether you’re hitting the gym on a stationary bike or exploring the great outdoors, this low-impact exercise is perfect for de-stressing and tiring out your muscles.

4. Swimming

Swimming works wonders for your whole body—it’s a full-body workout that’s also incredibly calming. The repetitive motions and soothing water can help relax your mind, making it easier to drift off later.

5. Dancing

Who says cardio has to be boring? Put on your favorite playlist and dance like nobody’s watching! Not only is it a fun, mood-boosting workout, but it also gets your heart rate up and leaves you feeling pleasantly tired.

Timing Matters: When Should You Do Cardio for Better Sleep?

You might be wondering, “When’s the best time to do cardio for sleep benefits?” Well, here’s the deal: Timing matters.

- Morning: Morning cardio is a fantastic way to wake up your body, get your metabolism going, and set your circadian rhythm for the day. Plus, exposure to natural sunlight while you exercise can reinforce your body’s internal clock.

- Afternoon: Afternoon workouts are ideal for those who want to maximize performance. Your body temperature and energy levels typically peak around this time, so you might find cardio easier and more enjoyable.

- Evening: While evening workouts are better than no workouts, avoid intense cardio within two hours of bedtime. High-intensity exercise can raise your adrenaline levels and make it harder to wind down.

Tips to Maximize Cardio’s Sleep-Boosting Benefits

1. Stick to a Routine: Consistency is key. Try to work out at the same time each day to help regulate your body clock.
2. Don’t Overdo It: Over-exercising can actually have the opposite effect and disrupt your sleep. Aim for moderate-intensity cardio, around 30–60 minutes per session.
3. Hydrate Wisely: Drink plenty of water to stay hydrated during your workout, but avoid chugging water right before bed.
4. Combine with Relaxation Techniques: Pair your cardio routine with calming activities like yoga, meditation, or deep breathing for an extra sleep boost.
5. Listen to Your Body: Everyone’s sleep needs are different. Experiment with different times and types of cardio to see what works best for you.

Conclusion

At the end of the day (literally), cardio is a game-changer for better sleep. Whether you’re stressed, dealing with insomnia, or just feel like your sleep could be better, adding a regular cardio routine to your life might be exactly what you need. Think of it as a two-for-one deal: You’re boosting your overall health and improving your sleep. Win-win, right?

So, lace up those sneakers, find a cardio activity you enjoy, and get moving. Your body—and your sleep—will thank you. Sweet dreams!