In the news today:Identifying inappropriate sinus tachycardiaI have recently been under investigation for palpatations, rapid heart rate, dizziness. This has worsened over the last 6 months. I had an overactive thyroid a few years ago which gave me the same symptoms but this is fine. I had a 24 hour heart monitor that showed that even when I felt fine and wasn't vigourously exercising I had sinus tachycardia of up to 140 bpm. I was worried because on days when my heart felt really bad, the beats oer min must have been much higher. I have been put on beta blockers for a trial (which I am about to start). I am finding exertion harder in the last 2 weeks and get more breathless. I always thought of myself as reasonably fit (28yrs old). My legs also feel a bit wobbly and weaker. Can anyone tell me what else I can do to help my heart rate? Is it inappropriate sinus tachycardia? Can I exercise and will this help? Has anyone else the same symptoms?