As a physician, I often feel like a detective asking questions about a patient’s particular complaint in order to discover what could be the underlying source of the problem.

Whenever medical students come to my office to fulfill their residencies, I emphasize to them how important it is to listen to the patient and ask pertinent questions in order to get the necessary information to make an appropriate diagnosis.

In the case of fatigue, the most important question to ask is whether exercise (or increased activity) makes the patient feel better, worse, or the same.

Hypothyroidism is a condition in which thyroid hormone production is low. The thyroid gland, which sits in the lower part of the neck, produces thyroid hormones that are responsible for regulating the metabolic rate and energy production in every cell in the body.

So you can understand why an underactive thyroid gland would lead to fatigue.

Hypothyroidism can be treated either with thyroid hormone replacement or by providing the thyroid gland with the raw materials it needs to regain normal function.

Exercise is a universal therapy — there are very few conditions it does not help. No other therapy benefits more conditions than exercise.

But one condition exercise can exacerbate is low adrenal functioning, also called hypoadrenalism. The adrenal glands are located at the top of the kidneys. They produce hormones such as cortisol, norepinephrine, DHEA, and pregnenolone.

When a person is under stress, the adrenal glands secrete greater amounts of stress hormones to help survive the situation.

When people exercise, the adrenal glands must release increasing amounts of cortisol, DHEA, pregnenolone, and other hormones to help the body get through the exercise and allow it to properly recover afterward.

If adrenal hormones are deficient, a person will feel worse after exercising. In fact, most patients with low adrenal function report feeling much worse for days after exercise or being exposed to some fairly stressful event. Some patients have even told me that they have to stay in bed for a long period of time after exercise or some other stressful event.

The thyroid and adrenal glands are closely linked. Thyroid hormone is the fuel that powers your cellular engine, like gasoline for a car engine. When you step on the accelerator of your car, the engine receives gas, which is burned to provide fuel for the transmission to engage and, voila, the car moves down the road.

Adrenal hormones are like the transmission that allows the cellular machinery to begin to produce ATP molecules, the energy storage units in the body.

In the case of a faulty transmission — which is akin to hypoadrenalism — putting your foot on the gas pedal will simple rev the engine and the car will go nowhere. If you continue to rev the engine, it will eventually burn up.

If a person has a low functioning adrenal and thyroid glands, it is important to balance the adrenal glands before providing thyroid hormone.

If thyroid hormone is taken first and the adrenal glands are unable to increase their hormonal production, fatigue will get worse.