INDIANAPOLIS (AP) One month after Indiana University Health's new sports cardiology performance lab opened, two new machines are getting their first real workout during the NFL's scouting combine in Indianapolis.

Doctors can simulate game-time conditions in elite athletes, giving them a better idea how hearts react to stress. The machines allow physicians to put larger athletes who tend to be in better shape than most of the general public on a wider, tougher treadmill and on a specialized bike.

The new machines allow doctors to measure much more than traditional electrocardiograms. The tests can monitor levels of expired oxygen, breaths per minute, and how big the breaths are per minute.

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''Football players work in intervals, so we'll do sprints at 12 to 15 mph for about 10 seconds and then we let them stop for about 30 seconds and do it again,'' said Dr. Michael Emery, the medical director for the Center for Cardiovascular Care in Athletics.

All combine invitees go through an initial heart evaluation, and if there are any concerns, they are sent to Methodist Hospital for additional exams.

Four players over the first two days of the combine went to the lab, though they were not identified because of federal privacy laws. None was found to have any significant heart problems.

Emery said there have been only seven people who have used the lab since it opened, but he has bigger plans for the facility, one of fewer than 10 in the nation to work with elite athletes.

Emery expects pro, college and high school athletes as well as weekend warriors with heart issues to come to the facility to get more detailed answers. Insurance, Emery said, covers most expenses if there is a referral.

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