If you want to perform at your best - whether in training, competition, or daily life - you need to manage your stress. However, stress and sleep have a two-way relationship, with high stress disrupting your sleep, and poor sleep increasing your stress. If you do not develop effective strategies for managing your stress, it leads to worse recovery, increased fatigue, and even impaired decision-making.
So how do you break free from the stress-sleep trap? Let’s start by diving into the science of stress, take a look at how sleep helps you regulate stress, and then cover some tips for helping you optimize sleep and keep you feeling in control.
Understanding the Sympathetic and Parasympathetic Nervous Systems
Stress isn’t just feeling overwhelmed, it’s a physiological response controlled by your autonomic nervous system which has two branches:
-
Sympathetic Nervous System (SNS) - The fight-or-flight response. This kicks in when you’re under pressure, whether from an intense workout, a big race, or daily life stressors. Your heart rate increases, cortisol levels spike, and blood flow prioritizes muscles over digestion and recovery.
-
Parasympathetic Nervous System (PNS) - The rest-and-digest response. This is the counterbalance to the SNS, helping your body recover, repair muscle tissue, and regulate emotions. When activated, your heart rate slows, blood pressure drops, and your body shifts into recovery mode.
In an ideal world, these systems would operate in balance. You push hard in training (SNS), then recover deeply at night (PNS). But chronic stress - whether from training overload, poor sleep, work, or emotional pressure - keeps the SNS active for too long, disrupting recovery and performance.
How Sleep Helps Regulate Stress (Backed by Science)
Sleep is one of the most powerful tools for stress management, acting as a reset button for both the body and mind. By regulating hormones, restoring the nervous system, and improving emotional resilience, high-quality sleep helps athletes handle physical and mental stress more effectively. Here are the specifics…
1. Sleep Lowers Cortisol and Regulates the Stress Response
Cortisol, your primary stress hormone, naturally follows a rhythm - it peaks in the morning and declines at night. But chronic stress and sleep deprivation elevate cortisol levels, keeping your body in a heightened state of alertness. Studies show that sleep deprivation can increase cortisol levels by up to 37% the following evening, making it harder to unwind and recover.
2. Deep Sleep Boosts Parasympathetic Activity
During deep sleep, your parasympathetic nervous system takes control, reducing heart rate and blood pressure. Research shows that athletes who get sufficient deep sleep experience a 20-30% increase in heart rate variability (HRV), the key marker of stress resilience.
3. REM Sleep Helps Process Emotional and Mental Stress
Beyond the physical, stress is also mental and emotional. REM sleep plays a critical role in emotional regulation and processing stress. Studies show that during REM sleep, the amygdala (the brain’s fear and emotion center) becomes less reactive, helping you wake up feeling mentally refreshed and more resilient to stressors.
When Stress Disrupts Sleep (And What It Means for Performance)
Chronic stress leads to hyperarousal (a state where your nervous system remains on high alert) - making it hard to fall asleep or stay asleep. Over time, this creates a vicious cycle:
- Poor sleep increases cortisol and reduces testosterone and growth hormone, impairing recovery.
- Reduced sleep impairs metabolism, leading to decreased endurance and power output.
- Cognitive fatigue sets in, increasing reaction time and reducing decision-making ability.
Olympic swimmer Michael Phelps has spoken openly about his struggles with stress and sleep, highlighting how mental strain can interfere with recovery. As one of the most decorated athletes in history, Phelps has emphasized that without proper sleep, both his physical and mental performance suffered. His experience underscores how even the best athletes are not immune to the impact of stress-related sleep disruptions - and the toll that it can take on performance.
Practical Strategies for Athletes to Optimize Sleep and Stress Management
Now let’s look at what you can do in order to manage your stress and maintain great sleep hygiene…
1. Control Light Exposure to Balance Cortisol and Melatonin
Get 10-30 minutes of morning light exposure to help set your circadian rhythm and make it easier to fall asleep at night. And limit blue light at night, as exposure to screens before bed can reduce melatonin production by up to 50%, delaying sleep onset
2. Use Breath-work and Meditation to Shift to Parasympathetic Mode
Practicing breath control, such as the 4-7-8 method, where you inhale for 4 seconds, hold for 7, exhale for 8, stimulates the vagus nerve, which controls the PNS. Also, just 10 minutes of meditation per day has been shown to improve sleep quality and reduce stress hormone levels
3. Prioritize Nutrition and Hydration for Better Sleep and Recovery
Magnesium-rich foods (nuts, spinach, dark chocolate) can promote relaxation and help regulate the nervous system. Meanwhile, avoiding caffeine after 2 PM can prevent sleep disruptions by fully clearing your system before you go to sleep.
4. Adjust Training to Account for High Stress Periods
Monitor your HRV and resting heart rate - if HRV is low and resting heart rate is elevated, it may be time to scale back intensity. Also, use active recovery instead of high-intensity workouts when under high mental or emotional stress.
So remember, stress isn’t the enemy - poor recovery, and not having proper techniques for balancing your stress is what causes problems. So let’s all actively think about how we can best manage our stress responses and prioritize getting deep, restorative sleep to help.
