skip to Main Content

How to Use Sleep to Improve Fitness and Health

By Tom Nikkola, CSCS, CISSN, Pn1

Core 3 Training E-BookImproving sleep is one of the most powerful ways to improve health and fitness. But it isn’t just about getting more time in bed. Improving sleep quality is as important as sleep quantity.

The following is an excerpt from the Core 3 Training E-Book. If you haven’t done so, be sure to download your free copy.

You may be surprised but, to us, sleep is the most important thing you can do to nourish your body.

Without sufficient, quality sleep, it’s difficult to eat the right foods day after day. In fact, it’s difficult to do much of anything right when your body is worn down, tired out and fatigued.

After we review the importance of sleep, we’ll talk about the best nutrition habits we recommend for our clients. If you want to learn about other strategies to further nourish your body, be sure to check our blog.

Insufficient sleep may be one of the most detrimental lifestyle choices people make every day.

Just one night of shortened sleep can have a significant, negative effect on metabolism. A lack of sleep has been shown to decrease insulin sensitivity, increase cravings for carbohydrate–rich food and sugar, and significantly decrease mental and physical performance.[i]

About one out of 25 people use prescription sleep aids.[ii] More than one–third of adults use an over-the-counter sleep medication.[iii]

Like many other medications, sleep aids come with a number of risks and potential side effects. Most common is their potential for dependency.

One of the major drawbacks from their use is that the quality of sleep is not the same. Yes, they help people get to sleep and sleep more hours, but it isn’t the best type of sleep. Sleep medications often interfere with the ability to reach deep or REM sleep. Achieving these two sleep states is critical to allow the body to physically and mentally recover from everyday stress and from exercise.

Because the lack of sleep can have such an effect on appetite and cravings, sleep is one of the first lifestyle/nutrition habits we address.

Sleep Quantity

Sleep quantity refers to the number of hours actually spent sleeping (not the amount of time just lying in bed). Insufficient sleep time, also known as sleep debt, is associated with a number of health problems and metabolic dysfunctions.

Sleep debt is a perfect term for what’s actually happening. Every night that you short yourself on sleep, you’re borrowing against your health and energy for the future. The big downside of sleep debt is that it can’t really be repaid. This is very important to understand.

You cannot make up for a lack of sleep during the week by sleeping in on the weekends.

According to the Center for Disease Control, the recommendations for sleep quantity by age group are as follows:[iv]

Age GroupRecommended Sleep (hrs)

For optimal health, you have to get 7 to 8 hours of sleep every night. Some adults even need 9 to function properly. And as you can see, kids need a lot more than adults.Note that the table above lists the recommendations per night. If you’re supposed to get 8 hours of sleep per night, you can’t aim for 56 hours of sleep per week and get 12 hours on some nights, and 4 hours on others.

Getting more sleep often means making adjustments to other areas of your lifestyle. It might mean watching less TV. It might also mean changing when you participate in sports or even adjusting your workout schedule. The same things can be said for kids and young adults who often need much more sleep than their parents do.

In one study, after just one week of 5 hours of sleep, men’s testosterone was shown to drop 10 to 15%.[v] Other studies show that shortened sleep may increase cholesterol levels[vi] and susceptibility to cravings for junk food,[vii] reduce neurogenesis (the development of new brain cells), [viii] reduce memory function,[ix] decrease leptin, increase ghrelin[x] and reduce insulin sensitivity.

Because insufficient sleep has such a big influence on food choices and metabolism, it makes sense to address the lack of sleep before trying to change dietary habits.

Lack of sleep reduces willpower and, based on the research mentioned above, significantly changes your metabolism. Not only do cravings increase, but when people give in to them, their body may more easily convert those foods to extra body fat. The lack of sleep may also contribute to a loss of muscle mass by increasing cortisol levels.

We understand that people may have a number of obstacles to getting 7 to 8 hours of uninterrupted sleep. But, in almost all cases except for those who have a newborn baby, it’s possible to increase the time spent sleeping by giving up something else in the evenings or early mornings.

Sleep Quality

Getting 7–8 hours of sleep every night is a great step in the right direction, but if most of that time is spent in a light state of sleep, your body won’t get what it needs.

Sleep quality is determined by the time spent in deep sleep and REM sleep. Deep sleep is the state that helps your body physically recover; the body releases its highest levels of growth hormone. Deep sleep typically takes place in the first third to half of the night.[xi] To maximize deep sleep, it seems that getting to bed well before midnight is helpful.

REM sleep is the state that supports brain function and enhances memory.[xii] REM sleep is at its peak in the second half to final third of the night.[xiii] It’s during this state that dreams are the most vibrant, which is why you may often remember a dream when the alarm goes off.

Sleep quality is determined by the time spent in deep sleep and REM sleep. Simply, deep sleep is the state that helps your body physically recover.

To improve sleep quality:

  • Turn down the heat, or turn up the air conditioning. Experiment with a bedroom temperature between 60 and 69 degrees.
  • Avoid blue light, such as from a TV or computer screen, for at least an hour before bedtime. Blue light limits the production of melatonin, which is important for getting into deeper stages of sleep.
  • Avoid excessive carbohydrates just before bed. Some carbohydrates in the evening can support creation of serotonin. But excessive carbohydrates keep insulin levels elevated which can disrupt nighttime hormone production.
  • Try some of the supplements recommended later on in this section. You may also try a combination of 5-HTP and PharmaGaba™. In addition, an essential amino acid formula like Amino Complex provides amino acids necessary for neurotransmitters, which can support restful sleep, as can extra magnesium.

Note: We just released Lean Complex – Restore, a new supplement to support sleep, using the combination of 5-HTP and PharmaGaba™. You can order Lean Complex – Restore from the Life Time online store.

  • Get rid of all light, even if it’s the light from a cell phone or nightlight. Your eyes might be closed at night, but even your skin can sense light. Keep your bedroom as dark as possible.
  • Avoid high-intensity exercise too close to bedtime. This may elevate cortisol levels which should be at their lowest before bed, not in an elevated state.

The following are some easy ways to increase the time you spend sleeping every night:

  • Go to bed at the same time every night. In doing so, your body will become accustomed to bedtime and you’ll fall asleep faster.
  • Turn down the lights and stop watching TV or using your computer an hour before bedtime.
  • Try supplements instead of pharmaceuticals. Some popular supplements that support sleep include melatonin, 5-HTP, GABA, Relora™, valerian and magnesium.
  • Herbal teas such as chamomile and lavender may be helpful.

Core 3 Training E-BookIf you thought this was helpful, you’re really going to love our free e-book.

Download the free Core 3 Training E-Book.



Help someone else out. Share this post on your favorite social media network.

[i] Prasai MJ, Pernicova I, Grant PJ, Scott EM. An Endocrinologist’s Guide to the Clock. J Clin Endocrinol Metab. 2011;96:913-922

[ii] Chong Y, Fryar CD, Gu Q. Prescription Sleep Aid Use Among Adults: United States, 2005-2010. NCHS Data Brief. Augus 2013. databriefs/db127.pdf

[iii] American College of Preventative Medicine. Over- the-Counter Medications: Use in General and Special Populations, Therapeutic Errors, Misuse, Storage and Disposal. Clinical Reference. Accessed July 29, 2014. resmgr/timetools-files/otcmedsclinicalreference.pdf

[iv] National Heart, Lung, and Blood Institute. How Much Sleep Is Enough? NHLBI Health Topics. Retrieved August 19, 2014. topics/sdd/howmuch.html

[v] EurekAlert!. Sleep loss lowers testosterone in healthy young men. University of Chicago Medical Center. May 31 2011.

[vi] Gangwisch JE, Malaspina D, Babiss LA, Opler MG, Posner K, et al. Short Sleep Duration as a Risk Factor for hypercholesterolemia: Analyses of the National Longitudinal Study of Adolescent Health. Sleep. 2010;33(7):956-961

[vii] St-Ogne M-P, McReynolds A, Trivedi ZB, Roberts AL, Sy M, Hirsch J. Sleep restriction leads to increased activation of brain regions sensitive to food stimuli. Am J Clin Nutr. 2012;95(4):818-824

[viii] Siegel JM. REM Sleep: A biological and psychological paradox. Sleep Med Rev. 2011;15(3):1389-142

[ix] Rauchs G, Desgranges B, Foret, J, Eustache F. The relationships between memory systems and sleep stages. J Sleep Res. 2005;14:123-140

[x] Taheri S, Lin L, Austin D, Young T, Mignot E. Short Sleep Duration is Associated with Reduced Leptin, Elevated Ghrelin, and Increased Body Mass Index. PLoS Med. 2004;1(3):210-217

[xi] Dijk D-J. Slow-wave sleep, diabetes, and the sympathetic nervous system. PNAS. 2008;105(4):1107- 1108

[xii] Nadel L, Payne JD. Sleep, dreams, and memory consolidation: The role of the stress hormones cortisol. Learning & Memory. 2004;11:671-678

[xiii] Cizza G, Requena M, Galli G, de Jonge L. Chronic sleep deprivation and seasonality: Implications for the obesity epidemic. J Endocrinol Invest. 2011;34(10):794:800

The posts on this blog are not intended to suggest or recommend the diagnosis, treatment, cure, or prevention of any disease, nor to substitute for medical treatment, nor to be an alternative to medical advice. The use of the suggestions and recommendations on this blog post is at the choice and risk of the reader.
Back To Top