1. Department of Physiology and Biophysics, School of Medicine, University of California at Irvine, Irvine, California;
2. Division of Kinesiology, Laval University, Quebec, Canada;
3. Division of Exercise Physiology; Department of Medicine, Columbia University, College of Physicians and Surgeons, New York, New York;
4. Department of Medicine, Columbia University, College of Physicians and Surgeons, New York, New York; and
5. Division of Molecular Genetics, Departments of Pediatrics and Medicine, Columbia University, New York, New York