Health Conditions & Chronic Disease

What to Know About Training Clients with Hypothyroidism or Hashimoto’s

In the United States, hypothyroidism affects nearly 5 out of 100 Americans aged twelve and older.

As such, if you’re a personal trainer, it’s likely only a matter of time before you come across a client with hypothyroidism. So, what do you do in such a situation? How can you develop safe and effective training programs for clients with an underactive thyroid?

Well, it all starts with understanding the disease.

In this article, find out everything you need to know about hypothyroidism, including what it is, how it affects the human body, how it differs from Hashimoto’s, and, more importantly, tips on designing and implementing sensible fitness programs that better support clients diagnosed with the condition on their fitness journeys. 

Learn How to Become a Certified Personal Trainer Online in Less Than 6 Months

Personal Trainer Career Guide

What Is Hypothyroidism?

Hypothyroidism, also called “underactive thyroid,” is a medical condition where the thyroid gland cannot produce enough thyroid hormones to meet the body’s needs.

To understand the significance, you’ll first need to know what thyroid hormones do. Thyroid hormones help regulate metabolism; this refers to the various chemical processes in the body that break down food for energy production. In other words, thyroid hormones control the way the body uses energy.

That means these hormones affect nearly every facet of health—including heartbeat rate, body temperature regulation, and even weight changes.

Thus, clients with hypothyroidism (i.e., too few thyroid hormones) will often experience a “slow down” in their bodies’ important processes. This, in turn, manifests in symptoms like fatigue, increased sensitivity to cold, weight gain, joint pain, muscle weakness, slow heart rate, and depression.

Hypothyroidism Vs. Hashimoto’s: What’s the Difference?

It’s difficult to read up on hypothyroidism without encountering the term “Hashimoto’s disease,” along with, potentially, some confusion about the difference.

Now, although the two terms (i.e., hypothyroidism and Hashimoto’s) are often used synonymously, the catch is that they’re not. They’re two different health issues.

As previously mentioned, hypothyroidism is a condition in which the thyroid is not releasing enough of the hormones it produces. There are many causes, ranging from certain medications (e.g., lithium) to thyroid surgery to postpartum thyroiditis.

Here comes the (slightly) confusing bit. Hashimoto’s can also result in hypothyroidism. In fact, according to the American Thyroid Association, Hashimoto’s is the most common cause of hypothyroidism in the United States. But what is it, exactly? Answer: It’s a type of autoimmune disease.

More specifically, Hashimoto’s is a condition in which the immune system mistakenly attacks the thyroid gland, compromising its ability to produce hormones.

Medical practitioners typically differentiate between the two conditions by ordering a blood test to check for elevated levels of antibodies against thyroid peroxidase, an enzyme that helps produce thyroid hormones; the presence of these antibodies strongly suggests that the immune system is on the offense against the thyroid gland (i.e., Hashimoto’s).

Despite these differences, though, it’s worth noting that the signs and symptoms of Hashimoto’s disease are like those of hypothyroidism.

That means a client with Hashimoto’s will also be prone to fatigue, intolerance to cold, weight gain, joint pain, muscle weakness, slow heart rate, and depression.

Is It Safe for Clients with Hypothyroidism or Hashimoto’s to Exercise?

Joint pain, fatigue, heart palpitations, and muscle weakness—as a personal trainer, you might do a double-take and have reservations about having a client work out when they’re prone to these symptoms.

In turn, begging the question: “Should clients with an underactive thyroid, no matter from hypothyroidism or Hashimoto’s, work out?”

As it turns out, regular physical activity could relieve many of the symptoms associated with the two conditions, helping increase energy levels, support better sleep, combat depression, build muscle mass (which may support healthy weight management), and even improve cardiovascular health.

Tips for Training Clients with Hypothyroidism or Hashimoto’s

But, of course, there are just a few things to be mindful of when developing a fitness program for clients with hypothyroidism or Hashimoto’s; accounting for these will put you in the best place to help them maintain an active lifestyle safely and effectively.

Ensure Your Client Is Cleared for Exercise

First things first. Ensure your client gets approval from their primary healthcare provider to start an exercise program; by the way, here’s where you request a Medical Clearance Form.

It’s crucial for you to do so because your client’s doctor has the scope to evaluate any other underlying conditions or issues that may make exercise difficult or put them at increased risk of injury. They’re also aware of the specific medications your client is on, along with any resulting contraindications to exercise.

Ideally, you should also consult your client’s doctor to determine which activities are considered safe and which ones are to be avoided before developing their program.

Focus on Strength Training

As mentioned earlier, individuals with an underactive thyroid have a lower metabolic rate. This makes them more liable to gain weight and suffer secondary problems caused by carrying more mass than is healthy for their body, including joint pain and weak muscles.

Thus, highlighting the importance of strength training. 

Resistance training builds muscle mass, which is more metabolically active than fat mass (i.e., burns more calories at rest). This increases your client’s resting metabolic rate, potentially enabling them to stick to a calorie deficit to get to a healthy weight.

In short: Strength training can help your client boost their metabolism and alleviate joint pain.

That said, not all strength training exercises are suitable for clients with hypothyroidism or Hashimoto’s. Do account for their existing joint pain when developing their fitness programs.

Rather than programming high-impact exercises (e.g., plyometrics), focus on closed-chain, stable movements like squats and lunges.  

Oh, and because clients with an underactive thyroid get tired quickly, pay careful attention to exercise order. In general, always place free weight exercises—like the barbell squat or overhead press—at the beginning of the session, where your clients are best able to focus on what they’re doing.

Leave the machine work to later parts of the session.

This significantly lowers their risk of serious injuries (think about the consequences of a client losing focus due to fatigue on the barbell squat vs. the leg curl machine).

Start with Shorter, Lower-Intensity Sessions

Have your client start slow, especially if they’re new to fitness or have severe symptoms (e.g., extreme fatigue). Who said you have to offer one-hour coaching sessions exclusively?

To better cater to clients with hypothyroidism or Hashimoto’s, consider splitting up a single, traditional one-hour coaching block into two—or even three—sessions instead. Of course, it all depends on your client’s schedule; if they’re able to meet you two or three times a week, great! But if not, you could simply conduct a thirty-minute personal training session with them once weekly.

Slowly build your client’s fitness capabilities; keep a watchful eye on whether their body tolerates the overload process at each stage.

And only when you’re sure that your client tolerates the exercise programming well do you venture forward to add more intensity or duration.

It’s also a good idea to remind your client of the symptoms of overexertion to look out for during every session so they will be able to distinguish the difference between discomfort that is to be expected when exercising and discomfort that could indicate a serious problem.

Make sure they understand the importance of informing you at once should they experience any of the following: joint pain, dizziness, nausea, rapid pulse, excessive sweating, extreme muscle soreness, cramping, or chest pain.

Share Recovery Techniques Clients Could Try

Dealing with hypothyroidism and Hashimoto’s can be mentally draining in and of itself.

Throw in the pain of delayed onset muscle soreness (DOMs), and your client can quickly get discouraged with their fitness journey.

In addition to assuring them that DOMs are perfectly normal and would likely decrease in frequency and severity, you should also share recovery techniques that could speed up their post-workout recovery rate.

Two good examples include:

  • Active recovery: Activity helps increase the blood flow throughout the body, clearing blood lactate accumulation and “speeding up” the delivery of nutrients (e.g., amino acids) and oxygen to healing muscle tissues. Some of the best active recovery modalities for a client with hypothyroidism or Hashimoto’s include swimming and cycling; their low-impact nature translates to minimal risk of aggravating joint discomfort.
  • Compression garments: Compression clothing effectively guides blood toward the heart and increases the speed and volume through which it flows, which boosts recovery rates. When recommending compression clothing to your client, though, do make sure they pick the correct fit for themselves. The garment shouldn’t be so tight that it cuts off blood supply, but it also shouldn’t be so loose that air bubbles are visible.

Encourage Healthy Lifestyle Habits

Of course, helping clients with an underactive thyroid gland live their healthiest, fullest lives goes beyond helping them to work out or recover. Your client’s overall health and wellness also depend on their daily lifestyle habits.

Examples of positive lifestyle changes to encourage in your client include:

That said, always be mindful of your tone and wording when communicating positive lifestyle habits your clients should adopt. While lifestyle factors like nightly sleep duration and stress management can impact your client’s fitness journey, it is incorrect to assume that clients have total control over these factors.

So, try to obtain as complete a picture as possible from your client before encouraging specific lifestyle changes. For instance, a client who’s just welcomed a baby to the family may find it difficult to get seven hours of uninterrupted sleep.

Always use your judgment—and fall back on empathy when communicating with clients.

Schedule Regular Check-In Sessions

As with all clients, those with hypothyroidism or Hashimoto’s will need regular check-in sessions.

These sessions provide opportunities for clients to inform you of any hang-ups they may be experiencing with their program, allowing you to identify areas you could tweak to better support their journey.

Be sure to highlight their progress and achievements during these sessions, too. It’ll go a long way in motivating them.


Working with clients with hypothyroidism or Hashimoto’s shouldn’t be scary, even if it’s your first time.

Take the time to understand how the disease affects your client and work closely with them to find the most sustainable fitness approach that works for them. It might take a little longer to find what works, but it’s going to be worth it.

The most important thing to do throughout is to be empathetic and open to supporting your client on their fitness journey.

If you’re passionate about yoga, you can become a yoga guide by completing a certification course with AFPA and sharing your knowledge and practice with others.

Learn what it takes to become a Personal Trainer


Share this article
Article Categories: