...It wreaks havoc with people’s sleep cycles. Heart attacks increase 24 percent in the week after the U.S. “springs forward” in March. There’s even an uptick during the week in November when the clocks “fall back.” ... Very interesting. When I took my blood pressure at 10:00 this morning, my heartrate was 81 - within normal limits (60-100) but much higher than my usual pulse in the 50s or 60s. I didn't record the 10:00 numbers but took BP at noon when my heartrate had dropped to 72. Still a little high for me but definitely better than 81.