MRCP-0669
A 26-year-old technician with no past medical history presents to the neurology clinic complaining of muscle pain. He describes severe bilateral cramping calf pain on minimal exercise. This has been present since his late teens and as such he has avoided exercise. Recently, he has attended the local gym to try and lose weight, but attempts at exercise have been dampened by the pain. He does note that if he perseveres with exercise, the pain settles. He has noticed passing dark urine in the evenings following a prolonged bout of exercise. Which of the following clinical tests would be most useful in aiding the diagnosis in this patient?