Exercise Equipment Interference

This is a weird one! I changed from my iPod to my iPhone for listening to music while I work out at the gym. I use a cardio program on the treadmill which periodically asks me to hold the heart monitor handgrips so that it can adjust speed and grade percentage to maintain the proper heart rate for my age. I have found that the heart monitor function on the LifeFitness brand treadmill goes bonkers whenever I use a data function on my phone (checking email, etc.). I am not holding the grips but the heart rate digital readout suddenly jumps to hummingbird levels! The machine responds by suddenly jumping out of the program and going super slow and flat grade to keep the user from having a heart attack. This happens on all the machines. Bummer. Probably no fix possible on phone side, but the makers of these machines are going to need to build in shielding for these new generation devices.