Forearm exercise screening test for mitochondria myopathy

Jensen TD et al. A forearm exercise screening test for mitochondrial myopathy. Neurology 2002; 58:1533-1538. Authors comapred 12 patients with MM to 10 with mucular dystrophy and 12 normal controls. All subjects performed intermittent handgrip exercise (squeeze one second, rest one second) for 3 minutes. Blood samples were collected from median cubital vein before during and after exercise to measure oxygen saturation and lactate levels. MM patients did not have the normal oxygen desaturation seen in other subjects. The lactate test did not show a significant change. The authors propose this as a sensitive and specific screening test for MM, almoot as good as muscle biopsy.