Exercise is physical stress imposed upon the body, but it’s during the post-exercise recovery phase between workouts that the body actually changes as a result of the exercise stimulus. One of the most effective methods for recovering from a hard workout is something that you already do, but you probably don’t do enough of it, or you may not utilize it to the fullest extent. A sure-fire method of promoting recovery so that your exercise program produces the results you want is to get optimal sleep.

Achieving results from any exercise program requires having a post-workout recovery strategy and getting the optimal quality and quantity of sleep is one of the most efficient means of allowing your body to recover from one day’s workout and to properly prepare for the next exercise session. To help ensure that you are getting the most out of your workout program, check out these seven benefits of sleep for exercise recovery:

1. The National Sleep Foundation recommends that adults get between 7 and 9 hours of sleep per night. Increasing sleep time by one hour per night is like getting an entire extra night’s worth of sleep over the course of a week. When it comes to planning your workouts, keep in mind that the end of one workout is the beginning of the next, and how you recover (refuel, rehydrate and sleep) will allow you to be fully prepared so that you can achieve the best results possible.

2. One function of sleep is to allow time for muscles to repair themselves. Growth hormone is an anabolic hormone produced during stage 3 of non-rapid eye movement (NREM) or dreamless sleep and helps to repair tissues damaged during exercise; the longer a period of sleep, the more time for muscle tissues to regenerate and grow.

3. A full night’s sleep allows time for anabolic hormones to perform the function of tissue repair ; conversely, insufficient sleep could result in higher levels of catabolic hormones responsible for energy production. If you have ever been completely exhausted but couldn’t fall asleep, or if you did sleep yet woke up not feeling completely rested, it could be the result of elevated sympathetic nervous system (SNS) activity and higher levels of the hormone cortisol. The SNS releases cortisol, which helps convert free fatty acids into energy for exercise. However, when glycogen is in low supply, cortisol can also convert amino acids into adenosine triphosphate (ATP), which inhibits muscle growth.

4. Being overly tired, especially during exercise, could result in reduced reflex times or poor judgement, each of which could cause a training injury. One important benefit of sleep is that it allows time for the removal of unnecessary metabolic waste from brain cells. Think of sleep as the time when your brain is removing unwanted waste, while also enhancing blood flow to cells and bringing important oxygen and glycogen necessary for optimal cognitive performance.

5. Metabolic overload occurs when muscles exercise to the point of fatigue, exhausting the amount of glycogen available for energy production. While you’re sleeping, your body continues to digest carbohydrates from your diet and metabolize them into glycogen, which is then stored in muscles cells to fuel muscle contractions. One gram of glycogen in muscle cells can hold three to four grams of water; as glycogen is replaced, it helps to increase muscle size, which is another example of how your muscles grow while you’re sleeping.

6. Adequate sleep promotes optimal function of the immune system. Outside of traumatic injury, illness is the second leading cause of missed playing time for athletes, and no, you do not have to play sports to receive this benefit. No matter what your job may be, getting great sleep supports a strong immune system, which, in turn, reduces the risk of becoming sick. This allows you to optimize your performance and be more productive.

7. To ensure optimal performance during your workouts, it’s a good idea to plan your workouts based on the sleep you’ll be able to get each night. For example, if your evening plans include attending a concert or a late night out with friends, you are less likely to get the recommended seven to nine hours of sleep. This does mean you should skip your workouts; rather, you should try to schedule your high-intensity workouts on days when you plan to get a great night’s sleep and plan lower-intensity workouts on days when your normal nighttime routine might be disrupted. Taking your evening plans into account as you schedule your workouts can help to ensure that you are properly prepared for the more challenging workout sessions that can provide the desired results.