“I just can’t keep up like I used to.” 

It’s a familiar refrain as many adults grapple with a dip in energy levels as they get older. But where does the energy of youth go? 

A complex interplay of physiological factors and your daily choices influences aging and energy production. And although you can’t stop your body from aging, there are simple measures you can take to maintain and improve your energy along the way.

The quirk of aging: It’s not just numbers 

Aging isn’t a straightforward path. You’ve likely noticed that some people have the stamina of someone half their age, while others physically appear much older than they are. People age at different rates due to various factors, such as genetics and lifestyle.1 

But the chronological age of an individual doesn’t always reflect the body’s biological age. Even in the same person, various parts of the body can age differently. A recent study using a blood test to determine organ age found that some organs appear biologically older than the person. This significantly increases the odds of health problems. Some research shows that individuals with “older” hearts, for example, face a 250-percent increased risk of heart failure.1,2  

Tracing energy loss

Various physiological factors contribute to decreased energy levels and feelings of fatigue as you age. Common factors that make it feel like your fuel tank is never full include:

1. Changes to the body’s normal sleep rhythms. Over the course of a day, you experience a natural cycle of physical, mental, and behavioral changes. These are called circadian rhythms, and they influence important bodily functions, such as sleep, hormones, appetite, and body temperature.3 

Aging creates more disorganized circadian rhythms, disrupting body temperature and sleep patterns, which can leave you feeling tired. The rhythms responsible for the secretion of the hormone melatonin – which signals the body that it’s dark and time for sleep – weaken as you get older. This makes it difficult to maintain a normal sleep-wake cycle.1

As part of this circadian disruption, it’s common for older adults to go to bed earlier and wake earlier than when they were younger.1 

2. Loss of muscle and strength. Declining muscle mass and strength due to aging is a condition called sarcopenia. Sarcopenia causes muscle fibers to dwindle in number and size, making it difficult for the muscle to respond and to tire more easily.1,4

Muscle tissue is metabolically active, meaning it requires energy even at rest. When you lose muscle mass, your overall metabolic rate – or how quickly your body converts food into energy – decreases. This can lead to weight gain, reduced energy levels, and feelings of fatigue. 5,6

3. Bone loss and joint damage. The pain and discomfort caused by bone loss and joint deterioration might result in avoidance of physical activity, leading to feelings of fatigue. When you age, your body no longer regenerates and replaces bone as fast as it did when you were younger, leading to bone loss. Menopausal changes, vitamin D deficiency, and lack of weight-bearing exercise accelerate this loss.1,4

Cartilage, the cushioning between bones, loses water with age, which can cause joints to become arthritic. Tendons (the tissue that connects muscle to bone) and ligaments (tissues that connect bone to bone) also lose water. This leads to stiffening and reduced elasticity, which means less joint flexibility.1,4,7

4. Cell dysfunction. Aging compromises the ability of the mitochondria in cells to produce adenosine triphosphate (ATP), which is needed by cells for energy. This decline in energy production can contribute to the loss of muscle mass and function, and symptoms of fatigue.8-10 

5. Changes in the heart. Aging causes decreased cardiac metabolism, so the heart circulates smaller quantities of blood to the body. This can cause a person to tire more quickly and increase recovery time after physical activity. The maximum heart rate – the upper limit of what your cardiovascular system can handle during physical activity – also slows with aging. A sedentary lifestyle speeds up these changes.1,4

6. Inflammation. Increasing age is associated with elevated levels of various inflammatory molecules. As part of the natural immune system response, the body triggers inflammation to rid itself of invaders, such as bacteria and viruses. But sometimes, this response remains amplified, continuing long after the threat is gone. This can be the result of age-related factors, such as mitochondrial dysfunction or an increase in visceral fat (fat around organs like the liver), both of which are linked to increased inflammation. Chronic inflammation can contribute to diseases that affect energy levels, such as diabetes, heart disease, cancer, arthritis, and chronic obstructive pulmonary disease (COPD).8,11 

Fighting back against fatigue

Although some aspects of aging are inevitable, certain lifestyle habits and other proactive measures can mitigate the impact of aging on energy production.

Exercise. Moderate aerobic exercise for 30-60 minutes most days boosts energy and can improve overall health. Exercise can also help maintain muscle response time, increase muscle mass, and improve mitochondrial health. Researchers at Mayo Clinic found that three months of high-intensity interval training (HIIT) workouts reversed mitochondrial damage. Study participants, ages 18-30, who engaged in HIIT had a 49-percent increase in mitochondrial function, while an older group of HIIT participants, ages 65-80, saw a 69-percent increase.12 You can read more about the study here.

HIIT might be especially beneficial for older adults at improving cardiac function, reducing abdominal and visceral fat, and triggering the growth of new muscle.8,13 

Flexibility and balance exercises – such as hamstring and shoulder stretches, balancing on one leg, and tai chi movements – help keep joints mobile. Weight training or weight-bearing exercise, such as walking, coupled with resistance training (squats or bicep curls, for example) increase muscle mass and strength. Weight-bearing exercises can also increase bone density and slow age-related bone loss.1,4,8

Eat a balanced diet. Consume a nutrient-rich diet that includes a variety of fruits, vegetables, whole grains, lean proteins, and healthy fats. This ensures adequate vitamins and minerals, especially the nutrients most important for energy metabolism, such as B vitamins, vitamin C, iron, and magnesium.14

Some nutrients, such as vitamin B12, become more difficult to absorb as a person ages. In these cases, supplementation can offer a way to get the nutrients you need.14-16

Work your brain and seek enjoyment. Engaging in activities that challenge your brain can mitigate feeling unmotivated or fatigued. Try learning a new language or how to play a musical instrument. Stay on top of current events, such as politics, science, and the arts.  

Another energy booster? Maintaining a positive attitude. Some experts suggest positive emotions can light up “reward” pathways in the brain, improving mood and energy. Take part in activities you enjoy the most, such as a nature walk or volunteering at a local food pantry. Keep up with friends and family and spend quality time with them.17-19 

Get a good night’s sleep. Like younger adults, older adults need 7-9 hours of sleep each night. Following a regular sleep schedule, skipping naps and caffeine in the late afternoon or evening, and a cool, dark sleep environment can facilitate slumber. So can developing a bedtime routine that allows you to relax and wind down for the night, such as reading a book or taking a warm bath. Avoid using electronic devices before bed, because the blue light from devices can interrupt natural sleep patterns.20 

Talk with your health-care professional about medications. Certain medications commonly taken by older adults can trigger fatigue. These medications include diuretics, nitrates, and psychotropic medications.21 

Stay hydrated. Fatigue is a common symptom of dehydration. The sense of thirst declines with age, making it difficult to drink adequate fluid to stay hydrated. Dehydration is also more common in older adults because of mobility issues or conditions such as diabetes or kidney disease.22

Losing energy as you age is a complex process influenced by many internal and external factors. Because no two people age the same, it’s important to listen to your body and adjust your habits based on your individual needs. 

If you are experiencing persistent fatigue or have concerns about your energy levels and are otherwise healthy, consider consulting with a health-care professional for evaluation. Many other conditions, such as anemia, sleep apnea, Parkinson’s disease, diabetes, thyroid disease, and heart disease can cause fatigue.23

A word from Thorne

If you’re interested in delving deeper into your biological age (as opposed to your chronological age), Thorne’s Biological Age Health Panel analyzes the impact that lifestyle, nutrition, illness, and genetics have had on your body and vital organs, such as your liver and kidneys. Your Age Score provides insights so you can make changes that will improve your overall wellness and longevity.

References

  1. Taffet, GE. Normal aging. https://www.uptodate.com/contents/search. [Accessed March 4, 2024].
  2. Oh HS, Rutledge J, Nachun D, et al. Organ aging signatures in the plasma proteome track health and disease. Nature 2023;624(7990):164-172.
  3. Circadian rhythms. National Institutes of Health. https://www.nigms.nih.gov/education/fact-sheets/Pages/circadian-rhythms.aspx. [Accessed March 4, 2024].
  4. Effects of aging. American Academy of Orthopaedic Surgeons. https://orthoinfo.aaos.org/en/staying-healthy/effects-of-aging/. [Accessed March 4, 2024].
  5. Argilés JM, Campos N, Lopez-Pedrosa JM, et al. Skeletal muscle regulates metabolism via interorgan crosstalk: roles in health and disease. J Am Med Dir Assoc 2016;17(9):789-796. 
  6. Pataky MW, Young WF, Nair KS. Hormonal and metabolic changes of aging and the influence of lifestyle modifications. Mayo Clin Proc 2021;96(3):788-814. 
  7. Causes of fatigue in arthritis. Arthritis Foundation. https://www.arthritis.org/health-wellness/healthy-living/managing-pain/fatigue-sleep/causes-of-fatigue-in-arthritis. [Accessed March 4, 2024].
  8. Puett D. Biology of aging: identified drivers and interventions for optimal healthspan. ACSMs Health Fit J 2018;17-27.
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  12. Robinson M, Dasari S, Konopk A, et al. Enhanced protein translation underlies improved metabolic and physical adaptations to different exercise training modes in young and old humans. Cell Metab 2017;25:581-592.
  13. Marriott CS, Petrella AM, Marriott ES, et al. High-intensity interval training in older adults: a scoping review. Sports Med Open 2021;7(1):49. 
  14. Tardy AL, Pouteau E, Marquez D, et al. Vitamins and minerals for energy, fatigue and cognition: A narrative review of the biochemical and clinical evidence. Nutrients 2020;12(1):228.
  15. Eating to boost energy. Academy of Nutrition and Dietetics. https://www.eatright.org/health/wellness/healthful-habits/eating-to-boost-energy. [Accessed March 4, 2024]
  16. Nutrition as we age: Healthy eating with the dietary guidelines. U.S. Department of Health and Human Services. https://health.gov/news/202107/nutrition-we-age-healthy-eating-dietary-guidelines. [Accessed March 4, 2024]
  17. Older adults: Health and age-related changes. American Psychological Association. https://www.apa.org/pi/aging/resources/guides/older. [Accessed March 4, 2024].
  18. Positive emotions and your health: Developing a brighter outlook. National Institutes of Health. https://newsinhealth.nih.gov/2015/08/positive-emotions-your-health. [Accessed March 4, 2024].
  19. What do we know about healthy aging? National Institutes of Health. https://www.nia.nih.gov/health/healthy-aging/what-do-we-know-about-healthy-aging. [Accessed March 4, 2024].
  20. A good night’s sleep. National Institutes of Health. https://www.nia.nih.gov/health/sleep/good-nights-sleep. [Accessed March 4, 2024].
  21. Torossian M, Jacelon CS. Chronic illness and fatigue in older individuals: A systematic review. Rehabil Nurs 2021;46(3):125-136.
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