We all know the feeling of being in a stressful situation when the body’s fight-or-flight response kicks in. Your palms begin to sweat, your heart pounds, and your blood pressure rises as your brain signals that something may not be safe.

This response can be incredibly helpful when you need to respond to a real threat. However, when the body remains in this heightened state for too long, it can make it much more difficult to fall asleep.

Sleep requires the body to feel safe and relaxed. Below are five strategies to help shift out of fight-or-flight mode and into a calmer state.

1. Breathing exercises

Deep breathing can be one of the quickest ways to calm the nervous system. Studies have shown that just five minutes of breathing exercises per day can improve mood and slow breathing, helping activate the parasympathetic nervous system. One especially effective technique is the “physiological sigh.” Take a deep breath in through your nose, then take a second quick inhale through your nose, followed by a long, slow exhale through your mouth until your lungs feel empty. Practicing this for several minutes has the greatest impact, but even three breaths when you get into bed can help you feel more relaxed.

2. Limit caffeine

Coffee has its benefits, and for many people it feels essential. However, it can also increase anxiety and disrupt sleep. Research shows that higher caffeine intake is linked to increased anxiety, particularly at doses above 400 mg (about two to three cups of coffee). It can also reduce total sleep time, especially when consumed later in the day. One study found that participants who consumed caffeine slept 45 minutes less, with greater effects the closer it was consumed to bedtime. Because the half-life of caffeine is about six hours (and can vary by individual), experts recommend stopping caffeine intake at least eight hours before bedtime.

3. Progressive muscle relaxation

Progressive muscle relaxation involves tensing one muscle group at a time for 5 to 10 seconds, then releasing and relaxing for 10 to 20 seconds before moving to the next area. You can work from your feet up to your face, systematically tensing and releasing each muscle group (feet, legs, chest, arms, hands, neck, jaw, shoulders, etc.), followed by a few minutes of full-body relaxation. One study found that health care providers who practiced 30-minute sessions daily for seven consecutive days experienced significant reductions in poor sleep and anxiety, as well as decreased symptom severity. Because this technique is typically done lying down, it is a natural fit for bedtime.

4. Movement

Regular movement supports both physical and mental health and is a powerful tool for reducing anxiety. A key feature of the fight-or-flight response is an elevated heart rate, which can delay sleep onset. Research shows that individuals who exercise regularly tend to have lower resting heart rates and may find it easier to relax. Studies also suggest that regular exercisers have less intense reactions to stress, making them more resilient to its effects. Since stress is a major contributor to insomnia, this increased resilience can support better sleep. Movement does not need to be intense or time-consuming; simple strategies such as taking breaks from sitting, going for a short walk, or incorporating gentle yoga can make a meaningful difference.

5. Cognitive behavioral therapy

For some individuals, the nervous system remains highly activated, and self-guided strategies alone may not be sufficient. In these cases, working with a professional trained in cognitive behavioral therapy can be highly effective. Cognitive behavioral therapy has been shown to improve both anxiety and insomnia. If sleep difficulties persist for more than a few weeks, anxious thoughts are frequent, or sleep is impacting daily functioning, consider seeking support from a qualified provider.

Final thoughts

When the body is stuck in fight-or-flight mode, sleep can feel frustrating and out of reach. The goal is not to force sleep, but to help the nervous system feel safe enough to relax. Consistently practicing these strategies can help shift the body out of a heightened state and allow sleep to come more naturally.

Lindsay Anderson is a behavioral sleep specialist.