Balancing Sleep & Strength: Decoding the Best Sleep Duration for Muscle Growth (6 vs. 7 Hours)

6 hours of sleep may not be sufficient for muscle building; proper rest is crucial for lifters to benefit from their workouts.¹ If 6 hours of sleep is inadequate, 7 hours might still not be enough to effectively build muscle.

The truth is, no one wants their efforts at the gym but due to an increase in obligations, rise-and-grind mottos, or an otherwise busy lifestyle, it can be difficult to get a solid 8 hours of rest so many want to scrape sleep-wise by getting the bare minimum for recovery.

While this may work for some due to mutated genes, the rest of the population is better off dialing in the necessary amount of sleep for muscle growth with experimentation – which can give us insight into how much we need to feel rested, and how much sleep we need to make gains.²

How Sleep Affects Muscle Growth

Muscle growth does not end after a workout; recovery, especially during sleep, is key to becoming stronger.

Exercise, particularly strength training, causes damage to muscles which occurs as tiny tears in the muscle tissue. In reaction to this damage, the brain activates an immune response that acts to repair the tissue, reduce inflammation, and rebuild the cells within the muscles. A large portion of this process takes place during sleep.³

During the first 90 to 120 minutes of sleep, the body begins to relax and releases a large amount of human growth hormone, or HGH. This hormone is produced by the pituitary gland and is responsible for building and repairing muscle tissue.³

As sleep continues past the first 90 to 120 minutes, REM (Rapid Eye Movement) sleep is initiated and muscles begin the recovery process by using the HGH that was released at sleep onset. At this stage, the central nervous system, the control center of the mind and body, also begins to recover from the day’s activities.³

Throughout this process, the body reaches its lowest level of cortisol, which signals the brain to release melatonin. If adequate sleep is not attained, cortisol levels will not drop enough or will rise too early, which affects melatonin production. These lower levels of melatonin do not allow the body to transition efficiently from sleep cycles and can interfere with the restfulness of sleep.³

Photo by Shane on Unsplash⁴

Other Benefits of Restful Sleep

Not only does sleep aid in muscle recovery, but it has a myriad of other benefits. The U.S. Department of Health and Human Services has researched the benefits of restful sleep, which include:

• A healthier immune system
• Reduced weight gain
• Lowered risk of heart disease, diabetes, and other critical health conditions
• Better focus and attention
• Being less irritable
• Staying safe due to not being overly exhausted⁵

Is it Possible to Gain Muscle With 6 vs 7 Hours of Sleep?

It may sound counterintuitive, but when sleeping, the human body is doing quite a bit of work. Instead of expending energy on moving around, it is using that energy to recover from the events of the day. On days when strength training occurs, the body relies on the rest it is given to build up muscle after it is broken down.

In general, 6 hours of sleep is not enough for the average person to effectively repair and rebuild muscle cells.

In fact, lack of adequate sleep not only reduces the body’s ability to build muscle but can also cause dysfunctional metabolism which can lead to muscle loss.⁶

Research has uncovered a small percentage of people that carry a gene mutation, ADRB1, which affects how their bodies react to sleep cycles. These individuals have the unique ability to function on 6 or fewer hours of sleep because their quality of sleep is enhanced and more efficient. In other words, these individuals are able to fit 8 hours of sleep into 6 hours or less of sleep.²

7 or more hours of sleep is more in line with what a majority of people need to gain muscle. Although it doesn’t sound like a big difference, these extra minutes are used by the brain for psychological recovery and to release the adequate amount of hormones needed to aid in protein synthesis, which is the core of repairing muscles.⁶

This even more important for those trying to squat and deadlift same day because it’s very taxing on the CNS (central nervous system) and zero gains will be made with inadequate sleep even if there’s plenty of stimulus.

What’s the Optimal Range of Sleep for Weight Lifters to Build Mass? How Many Hours of Sleep Are Needed to Grow?

Unfortunately, there is no single recommended timeframe for rest that is optimal for every person. How much sleep for muscle growth is largely dependent on genetics, as mentioned previously, as well as the quality of sleep.

It is commonly heard that the ideal amount of sleep is 8 hours. As more research has been performed throughout the years, that number has become more of an average instead of a hard and fast rule. Many individuals’ bodies perform ideally when they’ve slept between 7 to 7.5 hours, while others may need 9 to 9.5 hours of sleep. These ideal timeframes may be dictated solely by genetics or a combination of genetic needs and sleep quality.

For most healthy adults, only getting 6 hours of sleep will likely hinder muscle growth. Calculating the amount of sleep that is ideal for muscle growth is recommended and will be outlined later in this article.

Does Sleeping Help The Human Body Grow?

While adults typically need somewhere between 7 and 9 hours of sleep; it is imperative for babies, children, and teenagers to receive anywhere between 8 and 17 hours of sleep. Because children and adults have different sleep patterns, it is essential for young people to achieve adequate sleep to ensure the production of HGH, which is essential in body processes.

Not only does HGH help muscles grow and recover, it promotes the growth of the whole body in children and adolescents. So for those on a beginner hypertrophy program with a desire to get jacked, don’t forget about the importance of proper rest.

What Do Studies Say in Relation to Sleep & Muscle Growth?

Sleep is still a mystery on several fronts and although research has been conducted year after year to pinpoint exactly what the body does while asleep, there is still so much left to discover.

In this quest for knowledge, various studies have been administered that research and report data relating to sleep and muscle growth.

Taking a closer look at two published studies in regards to sleep and muscle growth will help reaffirm the importance of sleep in relation to working out and recovery.

A study, published in the Journal of Musculoskeletal and Neuronal Interactions, questioned 10,125 students (ages 16 to 30) in regard to sleep habits and proceeded to test their grip strength. This study concluded that a majority of subjects who slept between 7 and 8 hours per night had higher grip strength than those who slept less than 7 hours per night and equal grip strength to those who slept more than 8 hours per night.⁷

An additional study, published by the Sleep Research Society, followed 11 basketball players from Stanford University to evaluate whether extended sleep would improve performance. The athletes kept a normal sleep pattern for the first 2 to 4 weeks and then slept for roughly 10 hours per night for 5 to 7 weeks for the last portion of the study. Testing concluded that during the periods of additional sleep, these athletes performed at a higher level.⁸

In looking at both of these studies, there is a vast difference in sleep needs. The most notable difference is the amount of energy expenditure between each group. While the study in regards to students begins to prove the correlation between sleep and muscle strength, the second study goes even further by suggesting one of the biggest benefits of adequate sleep is muscle recovery.

Is it Okay to Workout While Sleep Deprived or Will it Impair Recovery?

The benefits of working out while sleep deprived and the subsequent time it takes to recover is dependent on certain factors, such as how often one is working out with little sleep and the cumulative amount of sleep one is lacking.

If an individual typically gets 7 hours of sleep and has an off night where they only sleep 6 hours, there will most likely be minimal negative effects. Although tired, the body is able to function fairly well at this level of sleep deprivation.

However, if an individual who functions well on 7 hours of sleep reduces their sleep to only 6 hours in an effort to build muscle, starting a new routine, the impact could be significantly greater.

A core concept to understand and consider is a thing called sleep debt – which is the amount of sleep one’s body is missing out on. In the second example listed above, the individual is accruing 1 hour of sleep debt per night. This means, at the end of one week, they are lacking 8 cumulative hours of sleep.

Continually putting one’s body through the stress of working out when sleep-deprived will significantly reduce how well muscles recover due the regulation of metabolism being disrupted.⁹

Sleep Deprivation Also Reduces the Effectiveness of Workouts & May Lead to Injury

Along with the prognosis of poor muscle recovery, it is bad to work out with no sleep due to a lack of stamina and the heightened risk of injury. A workout is only as effective as the amount of energy that is put into it, therefore, minimal sleep can cause early muscle fatigue and lack of focus, which greatly reduces the efficacy of a workout.

It’s a common occurrence when people try to go hard in the gym on a workout plan for skinny guys to build muscle fast, but they neglect sleep and wonder why their results are subpar.

Along those same lines, if an individual is not concentrating on the form or does not have the power to finish a set, the likelihood of injury skyrockets. An injury not only causes a problem at the moment, but it can also cause massive setbacks for muscle-building progress.

Downsides of Sleep Deprivation

Sleep deprivation not only affects muscle growth and recovery, but its negative effects include many additional downsides.

1. Lack of sleep can affect mental wellbeing by causing memory issues, slow thinking, a minimal attention span, irritability, and can contribute to anxiety and depression.
2. Sleep deprivation can lead to obesity, diabetes, heart disease, immune dysfunction, etc.
3. Sleep debt can contribute to hormone imbalances which can stunt growth, harm reproductive health, affect digestion, as well as cause a multitude of other problems.

Suggested Reading: Deadlifting stunt growth

Recovering from lack of sleep is not as easy as it may sound. When the body loses an hour of sleep, research shows it could take up to 4 days to make up for that lost hour. To completely resolve sleep debt, it is possible the body needs 9 additional nights of sleep to feel adequately rested.[7]

Do Naps Help Muscle Recovery?

When feeling fatigued or overexerted, taking a nap can be at the forefront of one’s mind. While a nap may help with energy levels, it is not the type of sleep needed for muscle recovery.

As mentioned earlier, the bulk of muscle recovery happens during REM sleep, which is typically not reached for nearly 2 hours; while most naps only last between 1 and 2 hours.

If the urge to take a nap is constantly overwhelming, it may be beneficial to prioritize sleep and set boundaries so napping isn’t as tempting.¹⁰ Data shows that naps aren’t nearly as beneficial so it may be better to rest than to hit the gym in an attempt to harden muscles.

Since Caffeine Affects Sleep, is it Bad for Muscle Growth?

Some preliminary studies have been conducted on whether caffeine is a help or hindrance to muscle growth. One study related the amount of caffeinated coffee drank by 6,369 adults (ages 45-74) with their grip strength and concluded that those who consumed more coffee had a higher measure of strength.¹¹

Photo by NATHAN MULLET on Unsplash¹²

While the study cited above may suggest benefits, caffeine can negatively impact muscle growth if it affects sleep. Like a majority of things in life, moderation is key.

If an individual is consuming caffeine to the point they can’t sleep after a workout or are having to resort to sleep supplements to counteract the caffeine, then the likelihood of poor muscle growth is high.

What Other Things Can Affect Sleep & Subsequent Gains?

Evaluating what food hinders your ability to sleep, along with drinks, supplements, and any other outside variables can help in understanding sleep issues. To optimize sleep, forming new habits can optimize rest and, in turn, promote muscle growth. A multitude of things can affect restful sleep:

• Drugs and alcohol
• School and work schedules
• Stress
• Poor diet
• Illness
• Sleep disorders
• Incompatible sleep environment

How to “Calculate” How Much Sleep You Need to Build Muscle

Because so much of what a body needs is predetermined by genetics, sleep requirements are unique and vary greatly from person to person. Calculating how much sleep is needed to build muscle should be a process that anyone who is looking to make strength gains should prioritize.

Finding out the ideal amount of sleep is not as much of an equation, as much as it is an experiment. Evaluating muscle capabilities in relation to sleep quantities can begin to paint a picture of exactly how much sleep is needed to reach workout goals.

To pinpoint the amount of sleep needed:

• Step 1: Use current sleep and workout routine as a baseline
• Step 2: Record strength and endurance data for 2 weeks at sleep baseline
• Step 3. Adjust sleep by adding 30 minutes
• Step 4: Record strength and endurance data for 2 weeks at sleep interval
• Step 5: Repeat Step 3 and Step 4 until 9 hours of sleep is reached or progress is no longer notable
• Step 6: Analyze strength and endurance data in relation to sleep
• Step 7: Determine optimal sleep duration

Note, 30 minutes of sleep may also be deducted at a time if an individual is attempting to determine how little sleep they can perform on.

Making adjustments to anything hindering quality sleep can cause marked physical improvements. While those changes are ultimately recommended, it is important to note that any changes that are made to enhance sleep quality will alter the results of the above analysis. Therefore, improving sleep habits should be completed before or after determining optimal sleep duration.

How Much Sleep Does a Bodybuilder or Powerlifter Need to Make Progress?

Referencing the study regarding basketball players that was touched on above, athletes expending high amounts of energy benefit from extended nighttime sleep. Powerlifter and bodybuilder sleep routines should be determined by the means above but may go beyond the 9-hour time frame due to the extra stressors the body endures when working out to a certain magnitude.

Getting enough sleep is crucial for exercise and strength training. If you don’t sleep well, it can be hard to achieve and maintain muscle gains, stay motivated, and avoid injuries. To determine if 6 hours of sleep is sufficient for muscle building, it’s important to consider genetics and develop a personalized sleep plan tailored to individual needs.

Is 6 Hours of Sleep Sufficient for Muscle Building or Can 7 Hours Accelerate the Process?

As a rule of thumb to know quickly–7 hours of sleep will always be better for your recovery than 6 hours of sleep.

But this is highly genetic. In fact, studies have even reviewed people requiring less than 4 hours of sleep per night.

Ultimately, determining whether 6 hours of sleep is sufficient for muscle building, or if 7 hours is necessary, depends on your unique circumstances. Use the 7 steps mentioned above to discover what works best for you.