Walking performance and cardiovascular response: associations with age and morbidity--the Health, Aging and Body Composition Study.
                             
                            
                            
                                
                            
                            
                                
                            
                            
                            
                                
                                    
                                            
    Newman AB, Haggerty CL, Kritchevsky SB, Nevitt MC, Simonsick EM. Walking performance and cardiovascular response: associations with age and morbidity--the Health, Aging and Body Composition Study. J Gerontol A Biol Sci Med Sci. 2003 Aug; 58(8):715-20.