 From a couple of different sources that this can be a little more challenging, we think. So just take that into account. Make sure your calves, you do the best you can to kind of keep them cool now in the summer. This has been Jim Soffer with the University of Minnesota. A message from Little Falls Radio and local physicians of knowing the signs about heart attacks. Every 40 seconds, someone in the U.S. has a heart attack. That's nearly 800,000 Americans each year. A heart attack occurs when blood flow to the heart is blocked.