Hashimoto’s Disease, also called Hashimoto’s Thyroiditis, occurs when the immune system turns against the body’s own tissues. The immune system directly attacks the thyroid. This then leads to hypothyroidism, which is when the thyroid isn’t making the necessary hormones for proper body functioning. The thyroid plays a leading role in our body, as it is the controller of our metabolism. Without the right hormones, how quickly our body uses calories from what we eat can be greatly impacted. It is the most common thyroid disorder, affecting 14 million people in the United States.

Symptoms of Hashimoto’s disease can include an enlarged thyroid, which may appear as swelling in the front of the neck where the thyroid is located. Because Hashimoto’s leads to an underactive thyroid and reduced hormone production, many of the symptoms are related to slowed metabolism. These can include fatigue, weight gain, cold sensitivity, hair thinning or loss, depression, irregular menstrual cycles in women, and joint and muscle pain.

The exact cause of Hashimoto’s disease is not known, but there is a strong genetic component. Hormones also play a significant role, as the condition is about seven times more common in women than in men and most often develops in middle-aged women. Thyroid issues can also emerge after childbirth, and roughly 20% of those cases may progress to Hashimoto’s later. Other contributing factors may include excessive iodine intake from certain medications or supplements, as well as radiation exposure. In fact, increased rates of thyroid disease were observed in populations exposed to radiation, such as survivors of the atomic bombings in Japan. These risk factors, combined with genetic susceptibility, may increase the likelihood of developing the condition.

While personal trainers don't diagnose or treat Hashimoto's disease, understanding how it affects energy, recovery, and exercise tolerance can help you create safer, more effective programs for clients living with the condition.

Exercise can be beneficial for Hashimoto’s because it helps lower inflammation and stabilizes the functioning of the immune system. This is because exercise stimulates regulatory T cells which are big inflammation fighters. Also in the process, exercise may help regulate immune system activity and reduce overall inflammation. Exercise also stimulates the release of substances such as IL-6 that can play a role in regulating inflammation.

Just going for walks is a great start but depending on how the person feels, even high-intensity-interval-training (HIIT) can boost workouts and help manage Hashimoto’s. Exercise tolerance is a case-by-case situation and overdoing exercise will only worsen inflammation.

For fitness professionals, this means paying close attention to how each client responds to exercise. Progress should be gradual, with training intensity adjusted based on energy levels, recovery, and symptom flare-ups rather than following a one-size-fits-all approach.

For the people I have trained in this condition, we sometimes must do a trial-and-error approach to ensure the person is doing what their body permits without causing a flare up. It has been my job to scale back intense workouts but still give the client the encouragement and motivation that inspires them to keep exercise as a lifestyle change to support living with Hashimoto’s as best as possible. Many times clients avoid movement, thinking their condition prevents them from doing certain types of exercise so why try at all. Movement is medicine so if it’s just walking, it is doing the body good versus being sedentary and lethargic.

Unfortunately, there is no cure. Getting help is important to prevent the progression of the disease. If left untreated women can experience problems with fertility and the risk of high cholesterol increases.

There are some self-care, natural approaches to try to improve or prevent this condition. This starts with diet, making sure it consists of enough selenium, zinc, vitamin D, and iron. Some people with Hashimoto's find that reducing foods such as gluten, added sugars, artificial sweeteners, soy, or dairy helps them manage symptoms, although responses vary from person to person. Trainers should encourage clients to work with their physician or a registered dietitian before making significant dietary changes. Avoiding toxins can help as well, such as plastics, beauty products, and air fresheners or candles. Keep your air clean.

Hormones might be tyrant rulers, but regular movement, appropriate exercise programming, medical guidance, and a positive outlook can help clients manage the condition and continue living active, healthy lives. As fitness professionals, we have an opportunity to provide encouragement, adapt training when needed, and remind clients that every step forward counts.