L’hypothyroïdie nécessite-t-elle une augmentation de l’activité physique ?

Hypothyroidism—the underactive thyroid condition—does not inherently require increased physical activity as a treatment strategy. While regular, moderate exercise is beneficial for overall health and may help alleviate some common symptoms such as fatigue, weight gain, and low mood, it does not correct the underlying hormonal deficiency. The cornerstone of management remains thyroid hormone replacement therapy, typically with levothyroxine, titrated to achieve and maintain euthyroid status based on serum TSH and free T4 levels.

Patients with untreated or inadequately treated hypothyroidism may experience exercise intolerance, muscle weakness, and slowed recovery due to reduced metabolic rate and impaired mitochondrial function. In such cases, initiating vigorous or high-intensity training without medical optimization can exacerbate symptoms and increase injury risk. Therefore, clinicians recommend stabilizing thyroid function through appropriate pharmacotherapy before significantly increasing exercise volume or intensity.

Once euthyroidism is achieved, individualized aerobic and resistance training programs—aligned with age, cardiovascular fitness, and comorbidities—can support metabolic health, improve body composition, and enhance quality of life. However, exercise should be viewed as adjunctive, not therapeutic, for thyroid hormone deficiency. Patients should consult their endocrinologist or primary care provider before making substantial changes to their activity regimen, particularly if symptoms persist despite biochemical normalization.