The Science, and Art, of Sleep Part I
Sleep & Weight Loss
In part I of this extended article, we’ll discuss why sleep is so important for people who are trying to lose weight, add lean muscle mass, or both. If you’re having a difficult time achieving your goals, it may be related to your sleep, or lack thereof. By understanding why your body is not obeying your commands the way you’d like it to, that’s the first step toward changing that and getting the results you want.
Question: My goal is to lose fat and gain lean muscle mass, but for months now I’ve noticed that my workouts have been unproductive. Someone told me that sleep has a lot to do with this. Can you explain how, or why that is
Answer: That information was correct. The quality of your sleep determines which hormones in your body will do what. Think of them as the on-off switches that kick in your body’s ability to lose weight in a productive manner, and getting a productive night’s sleep is an important piece of that puzzler.
Question: I’ve heard that there are several different stages of sleep, and they’re important. Can you briefly go over these and what happens during those stages?
A: There are in fact four stages of sleep, with brain wave activity shifting from stage to stage. In order to understand how all this impacts on your weight loss, and on gaining muscle, it’s helpful to discuss the activity that takes place as we go through the four stages of sleep nightly.
Stage 1: Light Sleep: This is the time when your eyes start to get heavy and your muscles start to relax. Picture someone’s head bobbing as they sit through a boring meeting. During this stage, it’s easy to be woken up. The early portion of stage 1 sleep produces alpha waves, where you’re very relaxed, yet awake. As you continue through stage 1 sleep, there is an increase in theta wave activity. It’s easy to wake someone from stage 1 sleep; people often report that they have not been asleep if they are awoken during stage 1 sleep.
Stage 2: Sinking Deeper: Ever jump awake because you feel like you’re falling? You are experiencing the bridge between light sleep and beginning sleep. During stage 2 of sleep, the temperature of your body lowers, as does the frequency of your brainwaves. Theta waves dominate the activity of the brain. You’re moving into deeper and deeper relaxation. Stage 2 is home to what are called “sleep spindles”—seemingly random bursts of brainwave activity. Paradoxically, the purpose of these energetic bursts may actually be to inhibit brain activity to keep you asleep so you can move on to stage 3.
Stage 3: Deep Sleep: This is the restorative, delta wave-laden stage of sleep. Your brain waves are slowest, and your body is busy fortifying your immune system, building tissue, and preparing your body for the next day. Slow wave sleep occurs during the deep sleep cycle. Stage 3 is where the action takes place if you’re looking to add muscle mass.
Stage 4: REM Sleep: All sorts of interesting things happen during the “rapid eye movement” stage of sleep.Aside from the role that REM sleep plays in processing learning and memory, it may also be involved in emotional processing and may represent an adaptive response to stress. This is the stage in which we dream. Throughout the first three stages, our brains have been slowly sinking from beta to alpha, alpha to theta, theta to delta waves. Now, all of a sudden, when REM sleep begins, our brains shoot up to beta and gamma brainwaves!* Our bodies are paralyzed, but our minds are just about as active as when we are awake.
*Gamma brain waves also show up when we take in new information and during states of happiness. Experienced meditators have been shown to produce gamma brain waves during deep meditation.
Question: About how much of each do most people need to be healthy sleepers?
80% of our sleep time tends to be in stages 1-3 and 20% in Stage 4, or REM. That said, everyone’s different. On average, light sleep will take up about 50 to 60 percent or more of your night. The amount of light sleep you receive will have little impact on how you feel, because that’s the time not spent in deep sleep or REM. Deep sleep, on the other hand is likely to take up 10 to 25 percent (depending on your age) of your sleep. You can’t get too much deep sleep. Your body has its own natural drive for it, so once you meet that, and you’ll naturally start going into REM and light sleep.
Question: How does lack of necessary sleep impact our ability to improve our body composition (build muscle/ lose fat)?
Going through a complete sleep cycle ensures that you will pass through Stage 3 sleep, which has a significant affect on your body composition. Sleep directly affects hormones in your body that contribute to both muscle growth and muscle loss. A recent paper published in Medical Hypotheses groups these hormones into two categories: anabolic hormones (the hormones that promote muscle growth) and catabolic hormones (the hormones that can contribute to muscle loss). Sleep has a profound impact on both of these hormone groups.
Encouraging Muscle Growth
If you’re trying to increase muscle mass, one of the most important naturally-occurring anabolic hormones available to you is Growth Hormone (GH). Growth hormone, as its name implies, is the hormone that directly contributes to muscle growth. And, as it turns out, the release of GH is tightly linked with sleep.
Remember the stages of sleep, and how Stage 3 is so important for tissue repair? Research published in The Journal of Pediatrics has shown that 70% of GH is secreted during Stage 3 sleep, and that the total amount of GH released in your body is directly correlated with how much Stage 3 sleep you get.
In the next section we’ll discuss other hormones that are impacted by sleep and which make us feel either hungry, or satiated—and what we can do about all of this to achieve our goals.