Kritchevsky SB, Nicklas BJ, Visser M, Simonsick EM, Newman AB, Harris TB, Lange EM, Penninx BW, Goodpaster BH, Satterfield S, Colbert LH, Rubin SM, Pahor M. Angiotensin-converting enzyme insertion/deletion genotype, exercise, and physical decline. JAMA. 2005 Aug 10; 294(6):691-8.