If you’ve ever found yourself feeling unusually bloated or feeling sick more often, the root cause could be your sleep.
The science of the sleep/inflammation connection
What is the biology behind this relationship between sleep and inflammation? “We’re not quite sure!” says immunologist Jacob Offenberger. However, he added, there are two main theories that could help explain this. “The first has to do with the glymphatic system, which is essentially a waste clearance system for the brain and central nervous system. With less sleep duration or quality, this system is not as efficient, which leads to inflammation. Arguably more problematically, it creates a vicious cycle because Less waste clearance in the brain reduces deep sleep.”
The second concept focuses on blood pressure. “During restful sleep, blood vessels relax and blood pressure drops,” says Dr. Offenberger. “However, when you’re not sleeping well, blood pressure tends to rise, which can trigger inflammatory cells to turn on.”
Additionally, research shows that sleep deprivation often results in higher and more sustained levels of reported stress, which is known to trigger both inflammation and a dampened immune system.
How do we fix it?
Here’s a simple solution: sleep more, and get better quality sleep! Easy right?
In all seriousness, with so many different variables that can affect our sleep, the reality is that sometimes we just don’t have the time or ability to make the changes we need to get a good night’s rest.
But what if there was another possible way to reduce the inflammatory and immune system consequences that come with sleep deprivation? Recent research has looked at that by examining the relationship between sleep restriction, inflammatory and immune system markers, and exercise.
One such study divided subjects into three different groups: a normal sleep group that got eight hours in bed for five consecutive nights, a sleep restriction group that got four hours in bed for five nights, and a sleep restriction and exercise group that got four hours. Three sessions of exercise in bed and five at night.
The study found — like many previous studies — that sleep-restricted groups increased the activation of immune system and inflammatory pathways. However, the sleep restricted group that had exercise significantly less activation
Another study that followed more than 11,000 subjects for eleven years found that exercise can alleviate numerous potential negative effects of sleep deprivation, including inflammation. Interestingly, the main point of this study wasn’t even looking at that relationship, but the evidence so strongly pointed to it that it became a key finding. (Sometimes, the best things just fall into your lap!)
Another study focused on an older population—since aging has been linked to increased inflammation and poorer sleep quality—found that those who practiced moderate exercise had decreased inflammatory markers (cytokines, specifically) and improved sleep.
So, how much exercise should you do?
There is no cut-and-dry protocol but, as a physical therapist, here are my research-based recommendations: For those under 55, complete a minimum of three high-intensity interval sessions lasting at least 20 minutes each (preferably late morning) per At least 150 minutes of moderate-intensity exercise per week or on a weekly basis. For those over 55, complete a minimum of three 60-minute moderate-intensity sessions per week.
Being more active will not only help with sleep, and reduce the negative side effects when you don’t get enough of it, but it will also improve your quality of life in general.
Get in your 20-minute HIIT session today: