RT Journal Article SR Electronic T1 Why does the heart rate response to exercise predict adverse cardiac events? JF Heart JO Heart FD BMJ Publishing Group Ltd and British Cardiovascular Society SP 577 OP 578 DO 10.1136/hrt.2005.079400 VO 92 IS 5 A1 H C Routledge A1 J N Townend YR 2006 UL http://heart.bmj.com/content/92/5/577.abstract AB The physiological mechanisms responsible for determining heart rate during exercise are complex, and further research into “chronotropic incompetence” is clearly required