Treadmill work out and HR. changes.

Hi.  I have just got my first treadmill in March to try to get into shape.  I am a 41 yrs old Female ~ 30#s over weight.   Since Feb. I've been very aware of my heart beat and mild pains in my chest every few minutes, with a few bad episodes leaving me feeling with a sunken feeling in my chest for a couple of months.   If they get to bothering me now, I get on my treadmill and try to forget about them.   Thinking at times maybe it's just me.  
I get on it at least two times a day for 20 minutes at 2 mph. and inclined at the 3-4 level.  My HR used to climb from 70 to 145 within a few minutes and then gradually go back to the 70's range.
Now it is going from 72 to 116 (feeling weak/ light headed) to 52 for awhile and then go back to the 100's range again and visa versa.  Is this normal?   This has just been the last couple of days.
I have a workout room on the 3rd floor of our house, but the walk upstairs will raise my HR from 70's to 145????, or cutting grass will go from 70's to 160 within minutes.  I don't get it.  Does most people have these kinds of changes while on a treadmill.  I can understand the changes from 70's to 116; but, I can't understand the drop (50's) in the middle part of the workout.  
Any comment would be helpfull.  Will be seeing my Dr. this week.  Just hoping to get any advise.  Thank you;
Amy

[erijon]

Your heart rate should increase with the level of activity. When you level out your maximum stress then your heart rate should stablize. After your peak stress, your heart rate should drop after exercise approx 12 -20 bpm in the first minute and continue to drop until it is back to normal. I personally try to maintain 140 bpm which is 85% of my maximum heart rate (220 - age), which is the reccommended level for peak cardiac health. My heart rate will go up to 140 -150 depending on how fast I push my stress level. I try to do a gradual warm up where I start at 2.5 MPH and 0 incline and by 5 minutes I work up to 4.0 mph and 5 degrees of incline which I will maintain for 35 -40 minutes and I will then take 10 - 15 mins to gadually work my way back to 2 mph and 0 incline by dropping a few tenths every minute. This is really easy once you get used to it. I'm a 50 year old male who has lost 60 pounds so far but still has about 50 to go. I wish I could go faster but I have severe OA in my knees and I just am not stable enough to run anymore.  I never miss a day as I have come to enjoy the work out. If I can do it, anyone can!

I don't think the kind of heart rate swings you're talking about are normal and I would reccommend that you see your doctor and get his ok to start an exercise regiment and also let him give you guidlines specific to your situation. You should always see a doctor before starting a new exercise routine and you really need to mention the swings in your heart rate as well.

Hope this helps,

Jon

[Me967]

Jon;  Thank you for your post.  
I have an appt. tomorrow AM.  I walked for a while today and it did not happen again.  I have been having some issues so I don't push my stress level on the treadmill.  I start at 0 incline and 1 mph for 2 minutes (HR ~72) then I incline it to 1 for a minute, then 2 for a minute or two, then go to 3.  On the speed I don't ha ha take it over 2.5mph.  But I raise it the at the same time as the incline every few minutes.  At peak; it peaked at 124 for a minute or two and then dropped again until it leveled out between 97-100.  I stayed there for about 15 minutes then reduced the speed and incline over the same 5 minutes as I did at the start.  When I totally slow down my HR goes up to 107-110.  ha ha ha.  Don't get it.  Stays there for about 10 minutes.  Maybe it's just practice makes perfect.  Just wanted to say thanks, and I will bring this up to her tomorrow.  By the way that's a really sweat car you have.  My picture is a Daytona 500 Pace car.  I Love it.

Thanks again;  Amy

[Me967]

Just thought I would let you know I went to the Dr. today and was told that if the drop was only once or twice it could be the handle bars on the treadmill and not to worry about it.  She also said (with the pills that I'm on) I will not be able to get my HR up and not to pay any attention to the HR.  If I feel light headed to just slow down, that if I was working up a sweat I was still getting a cardio workout.  Next week I have a echocardiogram and stress test; anyhow, I just thought I would pass that along to you.  

Sounds like your doing great by the way on your work out routine.  
Thanks again;  Amy