Heart Rate during Swimming

[TriJunk]

Hi all-

This is my first post here, so if for any reason this one is in the wrong section, I apologize in advance.  

I exercise quite a bit and typically average 5 hours per week running, 10 hours per week cycling, and 2-3 hours per week swimming (yes, I train for triathlon...).

That said, during the swim I have noticed that my Heart Rate does not increase much above 115 to 120 and it feels like my Heart is pumping very hard.  I check my pulse after 500m on my Carotid Artery and it seems to be a much stronger 'pulse' than when running or cycling.

I ask this question:  Is there possibly some sort of underlying issue going on with my health?  The 'Strong' pulse is strange to me, and I am concerned.  

I have no chest pain or anything like that.  My resting HR is right at 54 during the day and below 50 upon waking up in the morning.  My BP is low:  110 over 65 is a good average.

When running or cycling, I can easily get my HR up to mid 180's or low 190's if desired, although for endurance, I try to train no higher than 165 or so.

Any thoughts/ advice or ideas?

Thanks so much in advance.
Brett

[sony1215]

why it started pain after my first swim

[TriJunk]

Thanks.. that was a good read!

[Wisconsin2007]

Here's a relevant article:  http://host.madison.com/ct/news/local/article_060d8b8c-41a6-5dd7-ad38-2453dcebc1ea.html

[Wisconsin2007]

Tiring quickly would be pretty common, as I understand that the swimming portion of a triathlon is the most cardiovascularly intensive.

I don't have the knowledge to speculate why your heart rate would be that low if you were getting that tired.

And I don't mean to be alarmist, but in Wisconsin three triathletes have died during competition this year; all from heart issues, all during the swimming portion of the event.  So maybe it'd be worth talking to a doctor about this.

[TriJunk]

I am new to swimming, and might not be breathing properly, as I tend to tire quickly during this event.  Could a lack of oxygen lead to this issue?