6 Harmful Habits to Stop Right Now and 6 Healthier Habits to Start in 2024

Hopefully, you have a little downtime between the year-end holidays to reflect on what you want to accomplish in the coming year. It's the perfect time to look back on our habits and make intentional choices to feel better, maybe even fantastic. In the realm of health and wellness, our daily choices can profoundly impact our physical and mental states.

Reflection and exploration of what you need to stop and start

Let's explore eight habits that it's high time we bid farewell to, as they may be hindering us on our health journey. You may repeat these habits every day, several times a day. But they may be so ingrained you don't realize you're doing them or that they're taking a toll on your health.

Then, we'll delve into six habits worth embracing in 2024 – practices that uplift our mood, enhance our vitality, and contribute to a healthier, balanced, and fulfilling life. Join us on this journey and discover how you can transform yourself by leaving behind old patterns and welcoming new, positive rituals for a healthier, happier you.

The Unhealthy Habits

Excessive screen time before bed

These days, blue light is in nearly every type of electronic we use: T.V.s, smartphones, smart watches, computer screens. Even our lightbulbs are now blue light LEDs as standard, with the phasing out of the production and sale of incandescent bulbs officially going into effect this year.

Blue light, while it is beneficial during the daytime to signal to your brain that it's time to be up and active, can disrupt your natural sleep-wake patterns at night.

The blue light emitted from screens and lightbulbs can interfere with your circadian rhythm and negatively impact sleep quality. Blue light suppresses melatonin production, which is helpful during the day. But the suppression is stronger at night, holding melatonin secretion at bay for about 3 hours, cutting into your restful sleep.¹

A few tips

Stop using electronic devices at least an hour before bedtime (2-3 hours if you can manage it). Yes, it will be tough, but it will be worth it.

If you have LED lights around the house, dim or turn them off. Use dim red lightbulbs instead of white for night lights, which have less impact on your circadian rhythm.

If you work at night, consider wearing blue light-blocking glasses and find an app for your devices that filters the blue light wavelength in the evening.

Skipping breakfast

As you grab your bag and rush out the door in the morning, a few sips of coffee may be the only thing that goes into your stomach until a late lunch. Not eating breakfast cuts a few minutes from your morning routine, but in return, you gain no essential nutrients and energy for your day.

Not only does skipping breakfast mean that you may miss important nutrients during the day, including calcium, iron, vitamins A, C, D, B1, B2, and B3, but missing out on that meal has been shown to disrupt your circadian rhythms.²,³ This can reduce your sleep quality and make you tired and sluggish during the day.

A few tips

Kickstart your metabolism with a balanced meal at the start of the day.

You can shortcut the time to prepare breakfast by drinking a protein smoothie. You can even prep your smoothie the night before in a personal blender cup and blend the next day.

Whatever you eat in the morning is breakfast! If you are not an egg or cereal person, have a sandwich, salad, or roasted chicken and veggies left over from the evening before.

Mindless snacking or eating

You make hundreds of decisions about the food you eat each day. Turns out you're only consciously aware of a few of them.⁴ When you rely on visual cues to snack or continue eating, rather than internal signals telling you you're full, this leads to mindless eating.

Visual cues can include

• Eating “bottomless” entrees, soups, or appetizers that get refilled frequently.⁵

• Eating snacks directly from the large bag instead of using a bowl, plate, or smaller bag to consume an individual portion size.⁶

• Using a large plate for your meal. Trading plates for a smaller one gives you less room to serve yourself larger portions of food you may not need to satisfy your hunger.⁷

• Decreasing the amount of dishes that you have for one meal. When you have more selections and flavors, you take the visual cue to eat them all rather than just what you need to feel full.⁸a

• Seeing snacks can trigger you to eat them more frequently.⁹ Keep your kitchen counters tidy and free of foods in clear containers.

Overconsumption of added sugars

The occasional sweet treat is fine. In fact, it can help you make healthier meal choices!³⁸

However, the average adult in the U.S. consumes about 17 teaspoons of added sugars daily.¹⁰ For reference, a 12 oz. can of soda contains over nine teaspoons of sugar. The American Heart Association recommends no more than six teaspoons for women and nine teaspoons for men per day.¹¹ With one small soda, you've consumed all the sugar you should consume for one day.

That’s just soda. Sugar can sneak into your diet in ways you may be completely unaware of:

• Beverages - soda isn’t the only culprit. Sugars are added to bottled and canned sports drinks, teas, lemonades, vitamin drinks, juices, and flavored milks.

• Packaged fruits - while you benefit from eating fruit, some packaged fruit cups have about 39 grams (9 tsp) of sugar per serving due to the "light syrup" they contain. Toss an apple, banana, or orange into your sack lunch. It can be cheaper and is most certainly healthier.

• Yogurt - This go-to snack and breakfast food is favored because it contains some healthy probiotics. But sugar is usually the number two ingredient, with many brands containing up to 29 - 33 grams of sugar in a six-ounce serving (about 13 grams usually comes from the lactose in milk). That equates to about three teaspoons of sugar. But be vigilant: if the brand touts "low sugar," check the label; it most likely contains the artificial sweetener aspartame, which can be disruptive to your microbiome.¹²

• Breakfast cereal - This is no surprise, with many brands having the words sugar, chocolate, honey, or "frosted" right in the name. Stick with whole grain choices with very short ingredient lists, and no sugar is added.

• Sauces, dressings, and condiments - Tomato and pasta sauce has a surprising amount of added sugar, sometimes up to 12 grams per ½ cup serving (2.8 tsp). Sauces commonly have added sugar, with ketchup, relish, BBQ sauce, teriyaki, and hoisin sauce, all containing about four to six grams per one tablespoon serving. It may not seem like a lot, but note how much of these items you consume during a meal. You may find you're using when you use four to 16 servings for a dish or the whole meal. It adds up.

• Instant oatmeal and granola bars - these snacks are big perpetrators of piling on the added sugars. Many brands have upwards of 15 grams per serving (3.5 tsp).

Take an honest look and be mindful of what you eat during an average day. You may find several of these on your list, all adding to the total amount of sugar you consume daily. Swap out some of your packaged and bottled foods, drinks, and sauces for homemade choices, whole foods, and still or effervescent water with a slice of lemon or mint.

Neglecting regular movement or exercise

Moving your body daily is essential to good health, especially later in life.

The Physical Activity Guidelines for Americans state that adults need 150 of moderate physical activity every week.¹³ Splitting that into seven days equals a little over 20 minutes of daily exercise. Research suggests that only about 21% of adults meet this guideline.¹⁴

Studies are now confirming that a sedentary lifestyle (spending six or more hours per day sitting or lying down - not including sleep) can contribute to metabolic and weight issues, cardiovascular difficulties, serious conditions, and even early death.¹⁵

Some movement ideas

Hiking and brisk walking

Biking

Yoga

Dancing

Step aerobics

Intense cleaning housework

Swimming

Mowing the lawn

Badminton

Pickleball

Shooting hoops

Making choices like swapping out one episode of your favorite streaming series for a quick daily stroll around the block or on a treadmill significantly increases your physical health.  

Not getting enough quality sleep

While the amount of sleep you need varies individually, eight hours a night is a good rule of thumb.

When getting to sleep, staying asleep, or getting back to sleep after waking is difficult, this is when your health can begin to suffer. Consistent sleep deprivation can lead to a myriad of health issues, including impaired cognitive function, weakened immune system, mental health issues, and heightened stress levels.¹⁶

Establishing a regular sleep routine, creating a comfortable sleep environment, and avoiding stimulants before bedtime are essential to cultivating better sleep habits.

A few tips for better sleep

• Keep a consistent schedule. Go to sleep and get up at the same time, even on the weekends, when possible.

• Avoid blue light one to three hours before bed (see above).

• Don't eat large meals at least three hours before bedtime.

• Avoid caffeine in the afternoon at an appropriate time (varies per person).

• Get activity or movement in daily, but keep it during the daytime.

• Don't overdo naps, and only use them if they are needed. Keep them short, about 20 minutes, if you need to rest your eyes.

• Try out some relaxation techniques like some simple breathing exercises and meditation.

• Remember to get exposure to daylight during the day. Sunlight is a driver of your circadian rhythms.

• Keep your bed for sleep. Try not to do any smartphone scrolling, work on laptops, or watch T.V. while lying in bed.

Prioritizing quality rest rejuvenates the body and supports mental clarity, emotional resilience, and optimal daily functioning. Making sleep a non-negotiable priority is fundamental for your health and vitality.

Healthy Habits to Start

Mindful Meditation

Incorporate mindfulness meditation into your daily routine. Studies have shown for some time the benefits of a mindfulness-based stress reduction (MBSR) program in reducing stress levels.¹⁷ Techniques such as focused breathing and body awareness can help trigger your parasympathetic nervous system and kick in your relaxation response, leading to decreased levels of the stress hormone cortisol.¹⁸

Mindful meditation can also help improve focus and contribute to overall mental well-being.

A few simple meditation techniques

• "Do nothing" meditation - a chance to stop what you're doing and pause for a few moments.

• Focused breathing - sit for a moment and simply pay attention to your breath.

• Box breathing - a great way to immediately relax your mind and body when stress is high.

• Walking meditation - get in some steps while relaxing your thoughts and breathing naturally.

• Nature-inspired meditation - focus your attention externally on nature's beauty as a momentary break. Step outside, look up, or at a tree, flowers, or grass.

Hydration Challenge

Ensure you drink adequate water daily by starting a game-like "hydration challenge." Proper hydration is essential for various bodily functions and can positively impact everything from energy to digestion.  

Research has consistently highlighted the importance of proper hydration for many physiological functions. Many studies illustrate that even mild dehydration leads to decreased cognition and energy levels, dull-looking skin, lower physical and athletic performance, and sluggish digestion.¹⁹,²⁰,²¹,²²,²³

Making hydration a game with a “challenge”

Make sure you know approximately how much water you should be drinking daily. Use that number as your goal. A good rule of thumb is to take half of your body weight in pounds and drink that amount in ounces (i.e., a 128 lb. person should try to get in 64 oz. of water daily). Another recommendation from the National Academies of Sciences, Engineering, and Medicine is about 11.5 cups (91 oz.) for an adult woman and about 15.5 cups (125 oz.) for an adult man.²⁴

Use a sticky note on your refrigerator, bathroom mirror, or desk to check off every glass or bottle you drink during the day to keep track. You can easily find designed tracker sheets online to print out (or use this handy one here). Or use an app on your smartphone or smartwatch for tracking healthy habits.

Another technique to help you remember to get in your H20 is habit stacking. Drink a glass of water whenever you do any other regular activities during the day, like before or after your meals and snacks, taking supplements, brushing your teeth, taking a break, driving in or back from work or errands. Add a glass or bottle of water to whatever you do regularly daily. Habit created.

With a few "challenges" underneath your belt, adequate hydration will become a regular part of your everyday health routine.

Meal Prepping with the Right Foods

When you cook at home and meal prep for yourself or your family, you give yourself a healthy advantage with whole foods and meals where you know the exact ingredients. This can help you make better food choices and avoid relying on convenient but less nutritious alternatives. Packaged, processed, and even restaurant-prepared meals tend to be higher in fat, sugar, sodium, and additives that you may prefer to steer clear of on your health journey. The best way to do that is to prepare your meals at home.

Meal prepping offers many benefits beyond healthy meals and greater control over ingredients and cooking methods.

• Portion control - prepping allows, if you choose, to portion out your meals in advance. This helps prevent overeating and ensures you get the right calories and nutrients. Controlling the portions of food you eat is an essential aspect of maintaining a healthy weight.

• Cost savings - cooking at home can be more cost-effective than eating out. It has been hard not to notice that prices for eating out have risen substantially since 2020. Restaurant prices will increase by approximately 7.1 percent in 2023, with another increase of 4.9 percent in 2024. Grocery prices have risen, but at a much lower rate than eating out. Food-at-home prices will increase by approximately 5.0 percent in 2023, with a decrease of 0.6 percent in 2024.²⁵

• Time efficiency - although prepping requires some time upfront, it can save you significant time during the week. Spending a few hours on the weekend (or whenever is most convenient) preparing meals in batches means less time cooking and cleaning daily. Have a busy schedule? Prepping is definitely for you.

• Consistent nutrition - meal prepping ensures a more consistent and balanced intake of nutrients. Planning your meals in advance makes you less likely to resort to quick, unhealthy snacks or fast food options when you're hungry. This helps you maintain energy levels and support overall good health.

• Reduced stress - knowing that your meals are already prepared and waiting in your refrigerator or freezer for you can reduce daily stress related to food decisions. This is particularly helpful during busy workweeks or when balancing multiple responsibilities with family, community groups, volunteering, or other activities.

• Skill development - regular meal prepping encourages honing and developing cooking skills. Over time, you may become more proficient in the kitchen, have more precise knife skills, learn new recipes, learn a wider variety of cooking methods, and gain a better understanding of nutrition. Competency as a chef can be a rewarding aspect of the meal-prepping process.

Special note about the foods you select

Be sure the nutrition you’re getting is right for your biochemical individuality. Unfortunately, just plain "eating healthy" is not quite enough. You may be feeding your body and microbiome foods everyone knows are healthy, but they may not be healthy for YOU right now. Discovering the specific foods, nutrients, and biotics that are right for your body and microbiome is easy with a simple, at-home Viome Intelligence Test.

Pro Tip!

Take advantage of the new large language A.I. model platforms to do the work for you and create full weekly menus with breakfasts, lunches, and dinners (snacks, too). This is a huge shortcut that helps put you right on the foods you need, according to your Viome test recommendations. Popular platforms include chatGPT from OpenAI, BARD from Google, LlaMA from Meta, and Bing Chat from Microsoft.

Digital Detox Days

Introduce a few hours, days, or even whole weekends for a digital detox. This is an opportunity to disconnect from technology and engage in activities that promote relaxation, regeneration, or spending time with loved ones.

Over time, benefits you can experience include increased mindfulness, decreased feelings of stress and anxiousness, improved focus, concentration, and productivity, boosted confidence, and increased connection to those you love.²⁶

Some suggestions of what to do instead of deep diving on your devices

• Read a book - immerse yourself in the pages of an actual book you've wanted to read. You don't even have to purchase a book. Do you remember libraries? You’re probably very close to one right now.

• Get some movement - get in some physical activity. It doesn't matter what it is: a stroll, a stretch, some tai chi, a bike ride, or even high-intensity interval exercise. Just move that body.

• Do some work around the house - do you have a few DIY or organizing projects on your list? This is an excellent opportunity to get those done. Put on some music and clean up!

• Visit a local museum - spend a few hours or the day appreciating culture from your community or around the world in your local museums or art galleries.

• Have a picnic - pack a basket or cooler with some healthy foods and get outside for a while. Relax on a blanket in the grass or a picnic table in a local park for some fresh scenery and nature sounds.

• Volunteer - spend time with others in your community who need a helping hand at a food bank, soup kitchen, or community center. You may even get a few healthy benefits yourself.

• Exercise your brain - challenge your brain with crossword puzzles, Sudoku, jigsaw puzzles, or even a good, long chess game with a friend.

Put in a Regular Stretching Routine

Regular stretching of your muscles has been shown to help improve flexibility, reduce muscle tension, enhance circulation, reduce stress, improve posture and joint health, and help prevent injuries.²⁷,²⁸,²⁹

This can be a genuinely relaxing ritual that doesn't necessarily need any smart devices and gets you in communication with your body and your breath. Grab a blanket or a yoga mat, and run through a simple routine as a regular healthy habit. Double up on the benefits by stretching outside and also get some fresh air and sunlight.

A few tips for getting started

• Be sure to research proper form and technique - even gentle stretching can have its risk of injury if you are unfamiliar with good form and proper techniques. Harvard Health, Mayo Clinic, and WebMD all have good guides on how to stretch correctly.

• Start gradually - begin with very gentle stretches, especially if you are new to the activity. This helps your body adapt to the new movement, and you can increase your reach and intensity over time.

• Warm up first - getting your body warm before any movement or activity increases the blood flow to your muscles and helps avoid injury. This can be very light cardio exercise like jogging in place or jumping jacks for about five to ten minutes.

• Focus on major muscle groups - stretch your major muscle groups, including your quadriceps, hamstrings, and calves in your legs, hips, shoulders, and back.

• Breathe - don’t hold your breath when stretching. Breathe deeply and regularly during each stretch. Inhale as you prepare to do the specific stretch you’re doing, then exhale as you gently deepen it.

• Listen to your body - pay attention to how your body responds to each stretch. You should feel a gentle pull, not pain. If you experience pain, ease off the stretch.

• Stay consistent - aim for a regular stretch routine, either alone or with any regular activity or movement practice you may have. Even a few minutes of stretching each day can make a significant difference over time.

Spend More Time Outdoors

Being outdoors is so good for your body. Not only do you get a good dose of vitamins via sunlight, but you also get exposure to fresh air; you are probably getting some movement in, and you (hopefully) don't have a device in front of your face.

Some benefits of being outdoors, according to science

• Vitamin D production - exposure to natural sunlight allows the skin to produce vitamin D, essential for bone health, immune function, and overall well-being.³⁰

• Improved mental wellness - outdoor activities have been linked to reduced stress, anxiousness, and feelings of sadness. Nature exposure promotes relaxation and has a positive impact on mood.³¹

• Increased social interaction - being outdoors often involves social interactions, fostering a sense of community, and providing opportunities for social bonding, which is beneficial for mental health.³⁶

• Enhanced physical fitness - outdoor activities provide opportunities for physical exercise, helping to improve cardiovascular health, muscle strength, and overall fitness.³²

• Better sleep quality - exposure to natural light during the day and regulating circadian rhythms contribute to better sleep patterns and improved sleep quality.³³

• Boosted immune system -  spending time in nature has been linked to a strengthened immune system, possibly due to increased exposure to phytoncides (natural compounds released by trees) and the positive effects of reduced stress.³⁴

• Increased microbiome diversity - being outside exposes you to a wider variety of microorganisms, many of which can be beneficial for human health and your microbiome.³⁵  

• Stress reduction - nature has a calming effect on the nervous system, reducing stress hormone levels and promoting a sense of calmness and well-being.³¹

• Improved respiratory health - fresh outdoor air (more rural than the city) is generally cleaner than indoor air, contributing to better respiratory health and reducing the risk of respiratory issues.³⁷
  

Here’s to a healthier year for you

Breaking free from harmful habits is a pivotal step towards a healthier 2024 and a more fulfilling life. By letting go of these behaviors, we create space for positive change and personal growth.

Embracing healthier habits promotes physical well-being and nurtures your mental and emotional resilience. Let this be a year of mindful choices, prioritizing self-care, and cultivating habits that contribute to our overall happiness and longevity.

Here's to a transformative and health-conscious 2024, marked by pursuing habits that empower and uplift us.

References:

¹ Blog, Staying Healthy (2020, July 7). Harvard Health Publishing, Harvard Medical School. Online at health.harvard.edu

² Fanelli S, Walls C, Taylor C. (2021). Proceedings of the Nutrition Society. 2021;80(OCE1):E48. doi:10.1017/S0029665121000495

³ Jakubowicz D., Wainstein J., Landau Z., et al. (2017). Diabetes Care 1 November 2017; 40 (11): 1573–1579. doi.org/10.2337/dc16-2753

⁴ Wansink, B., & Sobal, J. (2007). Environment and Behavior, 39(1), 106-123. doi.org/10.1177/0013916506295573

⁵ Wansink B, Painter JE, North J. (2005). Obes Res. 2005 Jan;13(1):93-100. doi: 10.1038/oby.2005.12. PMID: 15761167.

⁶ Wansink, B. (1996). Journal of Marketing, Vol. 60:3 (July 1996), 1-14

⁷ Wansink B, Cheney MM(2005). JAMA. 2005 Apr 13;293(14):1727-8. doi: 10.1001/jama.293.14.1727.

⁸ Rolls, B. J., Rowe, E., Rolls, E., Kingston, B., Megson, A., & Gunary, R. (1981). Physiology & Behavior, 26(2), 215-221. doi.org/10.1016/0031-9384(81)90014-7

⁹ Wansink B, Painter JE, Lee YK. (2006). Int J Obes (Lond). 2006 May;30(5):871-5. doi: 10.1038/sj.ijo.0803217. PMID: 16418755.

¹⁰ 2015 - 2020 Dietary Guidelines for Americans. Department of Health and Human Services - USA

¹¹ American Heart Association editorial staff (n.d.). “How much sugar is too much?” Blog, Healthy Eating > Eat Smart. American Heart Association, online at heart.org.

¹² Shil A, Chichger H. (2021). Int J Mol Sci. 2021 May 15;22(10):5228. doi: 10.3390/ijms22105228. PMID: 34063332; PMCID: PMC8156656.

¹³ 2008 Physical Activity Guidelines for Americans. (2008). U. S. Department of Health and Human Services. Online at health.gov/paguidelines.

¹⁴ Data & Statistics, Physical Activity. (n.d) Centers for Disease Control and Prevention. Online at cdc.gov/physicalactivity.

¹⁵ Thorp, A.A., Owen, N., Neuhaus, M., Dunstan, D.W. (2011). AmJPrevMed. 2011;41(2):207–215

¹⁶ Sleep Deprivation and Deficiency. (updated 2022, Mar 24). National Heart, Lung, and Blood Institute. Online at nhlbi.nih.gov.

¹⁷ Kabat-Zinn J, Massion AO, Kristeller J, Peterson LG, Fletcher KE, Pbert L, Lenderking WR, Santorelli SF. (1992). Am J Psychiatry. 1992 Jul;149(7):936-43. doi: 10.1176/ajp.149.7.936. PMID: 1609875.

¹⁸ Davidson RJ, Kabat-Zinn J, Schumacher J, Rosenkranz M, Muller D, Santorelli SF, Urbanowski F, Harrington A, Bonus K, Sheridan JF. (2003). Psychosom Med. 2003 Jul-Aug;65(4):564-70. doi: 10.1097/01.psy.0000077505.67574.e3. PMID: 12883106.

¹⁹ Edmonds, C. J., Crombie, R., & Gardner, M. R. (2013). Frontiers in Human Neuroscience, 7, 55960. doi.org/10.3389/fnhum.2013.00363

²⁰ Armstrong LE, Ganio MS, Casa DJ, Lee EC, McDermott BP, Klau JF, Jimenez L, Le Bellego L, Chevillotte E, Lieberman HR. (2012). J Nutr. 2012 Feb;142(2):382-8. doi: 10.3945/jn.111.142000. Epub 2011 Dec 21. PMID: 22190027.

²¹ Palma L, Marques LT, Bujan J, Rodrigues LM. (2015). Clin Cosmet Investig Dermatol. 2015 Aug 3;8:413-21. doi: 10.2147/CCID.S86822. PMID: 26345226; PMCID: PMC4529263.

²² Cheuvront SN, Carter R 3rd, Castellani JW, Sawka MN.(2005). J Appl Physiol (1985). 2005 Nov;99(5):1972-6. doi: 10.1152/japplphysiol.00329.2005. Epub 2005 Jul 14. PMID: 16024524.

²³ “Your Digestive System & How it Works.” (last reviewed Dec 2017). Blog, Health Information, National Institute of Diabetes and Digestive and Kidney Diseases. Online at niddk.nih.gov.

²⁴ Kumar, K. (reviewed on 2023, Feb 1). Blog, Health & Living, MedicineNet. Online at medicinenet.com.

²⁵ Summary Findings, Food Price Outlook, 2023 and 2024. USDA Economic Research Service, U.S. Department of Agriculture. Online at ers.usda.gov/data-products.

²⁶ Mirgain, S. (2019, Apr 26). Blog, UWHealth, UW School of Medicine and Public Health. Online at uwhealth.org/news.

²⁷ “What is flexibility?” (n.d.) Learning Center Blog, UC Davis Sports Medicine. Online at health.ucdavis.edu/sports-medicine.

²⁸ Kim D, Cho M, Park Y, Yang Y. (2015). J Phys Ther Sci. 2015 Jun;27(6):1791-4. doi: 10.1589/jpts.27.1791. Epub 2015 Jun 30. PMID: 26180322; PMCID: PMC4499985.

²⁹ Lindberg, S. (updated 2023, May 19). [Stretching], Health Blog, Healthline. Online at healthline.com/health.

³⁰ Holick MF. (2004). Am J Clin Nutr. 2004 Dec;80(6 Suppl):1678S-88S. doi: 10.1093/ajcn/80.6.1678S. PMID: 15585788.

³¹ Jimenez MP, DeVille NV, Elliott EG, Schiff JE, Wilt GE, Hart JE, James P. (2021). Int J Environ Res Public Health. 2021 Apr 30;18(9):4790. doi: 10.3390/ijerph18094790. PMID: 33946197; PMCID: PMC8125471.

³² Gladwell VF, Brown DK, Wood C, Sandercock GR, Barton JL. (2013). Extrem Physiol Med. 2013 Jan 3;2(1):3. doi: 10.1186/2046-7648-2-3. PMID: 23849478; PMCID: PMC3710158.

³³ Blume C, Garbazza C, Spitschan M. (2019). Somnologie (Berl). 2019 Sep;23(3):147-156. doi: 10.1007/s11818-019-00215-x. Epub 2019 Aug 20. PMID: 31534436; PMCID: PMC6751071.

³⁴ Li Q. (2010). Environ Health Prev Med. 2010 Jan;15(1):9-17. doi: 10.1007/s12199-008-0068-3. PMID: 19568839; PMCID: PMC2793341.

³⁵ Smith DG, Martinelli R, Besra GS, Illarionov PA, Szatmari I, Brazda P, Allen MA, Xu W, Wang X, Nagy L, Dowell RD, Rook GAW, Rosa Brunet L, Lowry CA. (2019). Psychopharmacology (Berl). 2019 May;236(5):1653-1670. doi: 10.1007/s00213-019-05253-9. Epub 2019 May 22. PMID: 31119329; PMCID: PMC6626661.

³⁶ Eigenschenk B, Thomann A, McClure M, Davies L, Gregory M, Dettweiler U, Inglés E. Benefits of Outdoor Sports for Society. (2019). Int J Environ Res Public Health. 2019 Mar 15;16(6):937. doi: 10.3390/ijerph16060937. PMID: 30875938; PMCID: PMC6466442.

³⁷ Raju S, Siddharthan T, McCormack MC. (2020). Clin Chest Med. 2020 Dec;41(4):825-843. doi: 10.1016/j.ccm.2020.08.014. PMID: 33153698; PMCID: PMC7665158.