metabolic myopathy due to lactate transporter defect (MONDO_0009501, a Monarch Disease Ontology entry) is a rare metabolic myopathy characterized by muscle cramping and/or stiffness after exercise (especially during heat exposure), post-exertional rhabdomyolysis and myoglobinuria, and elevation of serum creatine kinase. Also known as: erythrocyte lactate transporter defect.