Like it or not, sleep and exercise performance are inextricably linked.

Whether you’re trying to adhere to a grueling new diet during a cut or you’re hoping to add a few more plates to a lift before the year is out, if you’re not following the proper sleep cycle, you’re bound to fall short at one point or another.

That’s why it’s crucial to know just how important a proper amount of sleep really is when it comes to reaching your fitness goals this year.

And while caffeine may have a number of significant benefits when it comes to shelling out peak performance, you may want to reconsider your consumption when you see just how important a full 8 hours really is for your body.

1. Proper Sleep Habits Are Essential for Repairing Worn Muscles

According to the science of muscle growth, the key to building up muscle is that the long proteins that make up your musculature (myofibrils) are both broken down (a.k.a. hypertrophy) and then repaired. This process of breaking down and repairing is instrumental both to building the size as well as the overall strength of the muscle.

While you may be tempted to put off sleeping in favor of spending an extra hour at the gym, the truth is that some of the body’s main tissue growth and repairs actually happen while you’re catching some Z’s.

True, the damage done to your myofibrils may start almost immediately after working out. But sleep expert Dr. Lisa Shives points out that “research indicates that much of [the body’s] repair work is done during non-REM, or NREM, sleep.”

According to the National Sleep Foundation, the particular sleep stage that this essential process occurs in is during stage 3.

What’s more, some researchers have actually hypothesized that sleep debt may in fact reduce “the activity of protein synthesis pathways and increases the activity of degradation pathways, favoring the loss of muscle mass and thus hindering muscle recovery after damage induced by exercise.”

Essentially, not only is a lack of sleep not giving you the time to repair damage from exercising. It’s also priming your body for muscle loss over time as well.

2. Hormone Regulation & Sleep Go Hand-in-Hand

One of the most notable benefits of a healthy sleep schedule when it comes to packing on muscle is that sleep and hormone secretion are intricately linked. And one hormone in particular is especially affected by sleep – human growth hormone.

This hormone, also known as HGH, plays an integral role in physical performance and helps improve tissue repair and allows the body’s muscles to both recover and grow. In fact, weightlifters around the world have actually been supplementing their nutritional regimen with this hormone since the 70s.

And while experts say that HGH is certainly no magic bullet when it comes to bulking up, it has been shown to give up to a 15% benefit to muscle gains when administered properly. Not too bad at all.

When it comes to natural production, almost 75% of HGH is actually released during the sleep cycle. The release schedule tends to happen in a “pulse” fashion, usually occurring during the beginning portions of stage 3. As the body enters the third stage, a quick burst of hormone release occurs before moving on to the fourth stage.

Throughout the nighttime, your body goes through an entire sleep cycle (i.e. from stage 1 to stage 5) about every 90 minutes. As such, if you aren’t getting as much sleep as your body needs to really recover, you could be missing out on several important chances for HGH release, making your exercises less effective and stifling your gains.

3. Sleep Can Be a Serious Problem for Motivation

We all know how integral motivation is for sticking with a workout regimen. Maybe it’s seeing your progressive gains over a few weeks or months. Maybe it’s witnessing the physical changes you’ve made over the years. Or maybe it’s just varying up your routine every now and then to keep things fresh.

Or perhaps you leave the motivation up to the expertise of your personal trainer.

And while these techniques are all well and good, there’s one simple strategy that researchers have shown may play a bigger role in motivation than you think: sleep.

It’s true – while sleep has been proven instrumental in the physical recuperation of the body, new studies have shown that it may play an important role in keeping you going back to the gym day in and day out. One study, for instance, found that sleep loss may directly affect performance as well as impact “effort-related choices we make.”

Part of this motivation effect is undoubtedly due simply to being more tired when you’re sleep deprived. However, a surprising number of America’s sleep deprived don’t even know they’re feeling sluggish because of it. In fact, after a few weeks of less-than-adequate sleep, most people simply stop recognizing the signs of being over tired.

The takeaway here is that even if you think you feel fine after only four hours of sleep, the truth is that you may actually be less motivated (and therefore less likely) to hit the gym.

And that can cause serious trouble for your fitness goals.

4. No Sleep & Working Out Means Poor Performance

Another one of the biggest reasons for getting a healthy amount of sleep every night is that neglecting to do so can be disastrous in terms of your fitness performance the following day.

According to Dr. Michael Breus, world-renowned sleep doctor, there are a variety of performance-inhibiting effects that researchers have found a lack of sleep can cause. In an interview with AskMen, he cites several of these including:

  • Reduced energy
  • Inhibited reaction time
  • Poorer visual tracking
  • Decreased accuracy
  • Ineffective decision making
  • Diminished memory
  • Slower recovery

While this can be especially problematic for serious athletes, poorer performance can also be troublesome for the casual lifter because it can inhibit progressive gains and make improvement much harder than it needs to be.

5. Lack of Sleep & Weight Loss Don’t Mix

Fitness professionals have long known that sleep and weight loss are intimately connected. And if your fitness goals are centered around aesthetics, reducing your waistline is absolutely essential for improving your muscle definition.

Here’s how it works: during your sleep cycle, your body releases a number of chemicals and hormones that help regulate your appetite as well as what kinds of foods you’re craving. Ghrelin and leptin, for example, are used to stimulate hunger and signal fullness respectively.

When your sleep cycle is thrown out of whack though, ghrelin tends to shoot up while leptin tends to drop – causing you to crave food and ultimately slip outside of your dietary plan.

Another bodily hormone called cortisol also comes into play here. A lack of sleep often correlates with a spike in cortisol. This is an important point to take note of because high levels of cortisol cause cravings for sugary foods.

And when all of these bodily chemicals combine, it can become harder than ever to stick to your fitness goals, no matter how motivated you may be.

6. Better Sleep Means Less Stress

Stress is a killer. And not just metaphorically.

The American Institute of Stress reports that a whopping 60% of illnesses and diseases can be traced back to stress. Beyond that, stress increases the risk of heart disease by 40%, heart attack by 25%, and the risk of stroke by 50%.

But what about exercise? Well, it looks like stress can play a major role in physical performance in the gym as well.

In the first place, stress can seriously impact performance alone. Motor coordination, concentration, visual acuity, and more have all been shown to be significantly impaired when under the influence of stress. These can all have some pretty damaging results when it comes to maintaining proper form and preventing injury.

And while you’re at it, you may want to kick your alcohol habits as well since it’s been shown to have a number of detrimental effects on exercise as well as stress levels too.

Sleep: Absolutely Instrumental for Meeting Your Fitness Goals

As you can see, sleep is far more important than most people realize when it comes to getting the most out of your workouts. In fact, many fitness professionals put it right up there with proper nutrition and meticulous form.

And it’s easy to see why – it gives your body time to repair itself, provides gain-boosting hormones, bolsters motivation, helps exercise performance, aids in weight loss, and reduces stress.

Ultimately, ensuring you get a full 8 hours isn’t just a great way to recoup after a grueling workout, it’s also one of the best ways to ensure you’re getting the most out of each and every session at the gym.

So, go ahead, get some rest. And be sure to head over to The Mecca Gym when you’re ready to hit it again.