Teach Yourself to Rest Read Free

Your Recovery Gap: Physical Recovery

Physical Recovery · 7 min read

Physical recovery is what happens when your body has a chance to restore itself after the demands of being awake, and sleep is a major part of that process.

When you're asleep, your brain is still doing really important work.

Sleep plays an important role in memory consolidation, helping stabilize and integrate what you've learned during the day and different stages of sleep contribute to different parts of that process.

Sleep is also connected to nervous system recovery.

One way researchers study this is through heart rate variability, or HRV. HRV refers to the small differences in time between one heartbeat and the next. Those differences are influenced by the autonomic nervous system, which controls functions like heart rate, breathing, and blood pressure.

One part of the autonomic nervous system, called the parasympathetic nervous system, helps shift the body toward rest. It slows heart rate and supports the body's ability to conserve energy and carry out processes that aren't about immediate action. The body needs this shift because it can't stay focused on responding to demands all of the time and needs periods when resources can be directed toward maintenance and recovery. When we don't get enough sleep, some of these measures show less of the activity associated with the body's rest and recovery processes.

Sleep may also help the brain with some of its housekeeping.

Research in mice has found that sleep increases the space between brain cells and is associated with faster clearance of beta-amyloid, a protein that can accumulate in the brain and is associated with Alzheimer's disease.

So during sleep your brain and body are still doing work. Really important work.

Pattern

A common pattern with physical recovery is that sleep gets deprioritized when there isn't enough time in the day for everything that needs to happen.

Sometimes that's a choice. Sometimes it isn't.

Motherhood and parenting;
Being a caretaker for a parent or a partner;
Shift work at odds with the schedule the rest of the world runs on;
and sometimes just periods of life when getting enough sleep is difficult.

A short night here and there and in demanding life seasons is part of being human.

The bigger concern is chronic sleep restriction, where you're repeatedly getting less sleep than you need.

Over time, that can start to feel normal simply because you're still functioning. Your schedule becomes familiar, even though your need for sleep hasn't changed. Getting used to a schedule doesn't mean your brain and body have adapted to needing less sleep. Repeated sleep restriction is associated with impaired attention and other aspects of cognitive functioning, even when someone continues to function day to day.

Belief

Part of this comes down to how we think about time.

Being awake feels productive while sleeping can feel like time we're not using.

So when there's work to finish, people to respond to, or something we want to squeeze into the day, sleep can be the easiest place to take an hour from. We can move bedtime, wake up earlier, tell ourselves we'll catch up on the weekend.

We can often get through the next day on less sleep, so it can feel like the tradeoff worked and that experience can reinforce the belief that if we can function, we had enough sleep.

However, functioning and recovering aren't the same thing.

Sleep restriction has measurable effects on attention and other cognitive functions, even when someone is still able to get through the day.

The Reflex

When we're tired, the automatic response isn't always to sleep, and sometimes we try to push through it.

While we're awake, a chemical called adenosine accumulates in the brain. As it builds, it contributes to the feeling that we're getting tired and need to sleep. This is sometimes called sleep pressure.

Caffeine works on this system because its chemical structure is similar enough to adenosine that it can bind to adenosine receptors in the brain. Adenosine normally binds to these receptors and can reduce neural activity in ways that contribute to sleepiness. Caffeine binds to the same receptors without activating them, so it prevents adenosine from having its usual effect. This is called receptor antagonism.

That's why a cup of coffee can make you feel more awake when you're tired. It hasn't removed the adenosine that has built up but temporarily blocks some of its effects.

So you can feel more alert without having gotten any additional sleep.

Behavior

Life is nuanced and complicated.

There will be nights when sleep gets cut short because life requires something from you. There will be periods when your schedule is difficult to change, and sometimes there simply isn't enough room for as much sleep as you'd like.

The useful thing to consider is what you can do with the room you have.

If you're in a season where sleep is regularly getting squeezed, that might mean protecting the sleep you can get rather than chasing a perfect routine. It might mean being more deliberate and intentional about what you take on and asserting boundaries to protect your recovery time or giving yourself more opportunity for sleep when the opportunity finally comes.

When you do have some control, small changes can make a difference. The goal isn't to make sleep another thing you're supposed to do perfectly, but to notice where you have some room to support recovery and use it.

Environment

The environment around us can make physical recovery easier or harder, and we don't always have control over those conditions.

Light, noise, temperature, and interruptions can all affect how easily you fall asleep and how well you stay asleep. Some of these things may be relatively easy to change, while others, like a work schedule, may be much harder to change or completely outside your control.

Shift work can make this especially difficult because the hours you're expected to sleep may not line up with the timing your body is naturally prepared for sleep, making it harder to get enough sleep even when you're doing what you can.

In these situations, it's useful to look at the environment alongside your behavior. If something around you is making sleep harder and you can change it, that change may be worth making. If the environment is limiting how much sleep you can get, that constraint needs to be part of how you think about your recovery.

You don't need to create perfect conditions for recovery. You need to understand which conditions you can change, which ones you can't, and make decisions about your recovery accordingly.

Sources

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