Energy and Fatigue Archive

People with anemia have an abnormally low number of red blood cells. Those are the cells that pick up oxygen from the lungs, deliver oxygen throughout the body, and return to the lungs with a load of carbon dioxide and other gases to be exhaled. Without enough red blood cells, the organs and tissues don't get a sufficient amount of oxygen. That can cause nonspecific symptoms, such as fatigue, headache, or wooziness, which are often attributed to other causes. As a result, anemia often goes undiagnosed.

Many factors can diminish men's energy levels, which can lower their libido and sexual stamina. The most common factors are naturally declining muscle mass, less production of the energy-carrying molecules adenosine triphosphate, low testosterone levels, and poor sleep quality. Addressing these issues through diet, exercise, medical therapy, and practicing good sleep hygiene can help improve men's energy levels for sex and daily life.

A new study from the National Institutes of Health has performed more diverse and extensive biological measurements of people experiencing chronic fatigue syndrome than any previous research. Here's what they found and what it means.

Fatigue is a relative term, meaning each of us evaluate our current energy level based upon how we feel most of the time. For example, people who are very energetic and go nonstop from early morning to late at night might say they have fatigue if they felt like most of us do every day.

Despite that variation, most people do have a sense when their level of fatigue feels like something more than just being tired. If that's case, even if it lasted only seven to 10 days, it's time to call your doctor's office. Signs that your fatigue might be related to an underlying illness or infection include low grade fever, night sweats, shortness of breath or loss of appetite. Other triggers for calling your doctor might be waking up exhausted despite a good night's sleep, not feeling motivated to begin the day, or struggling to do activities that are usually easy for you. 

Cardiopulmonary exercise testing (CPET) can help diagnose unusual causes of breathlessness, such as pulmonary hypertension or heart failure with preserved ejection fraction. CPET collects information about a person's heart and lung function to assess how the body responds to exercise. It may also help doctors better understand the lingering fatigue and breathlessness that sometimes occur after a COVID-19 infection.

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Q. I have been quite fatigued over the past two weeks. How long should I wait before seeing a doctor?

A. We all go through periods of low energy. Even a week of feeling more tired than usual is not uncommon.