I've had both the 310XT and the 910XT, and neither lasts more than 6 hours now. Using the heart rate monitor strap greatly impacts my battery life, for some rea

I've had both the 310XT and the 910XT, and neither lasts more than 6 hours now. Using the heart rate monitor strap greatly impacts my battery life, for some reason. I wish there was a way to tell how many cycles my batteries have left in them. I think it's time for an upgrade :)