pregnancy and max hr

[vigg]

Hi, I'm new here.
This has probably been griped about before numerous times, but I'm about 8 weeks pregnant and was warned during my first prenatal appointment that I should keep my hr at 140 or under. Having read that the 140 max was a pretty archaic guideline, I respectfully asked my MD to be a little more objective, especially considering that I, like most of you out there, can comfortably maintain a much higher hr for an extended amount of time. Her reposnse was that, after estimating my base hr was about 50, I really should keep my hr below 120 (yikes!). So much for objectivity.

I realize she's an md and all, but her concept of cardiovascular fitness seems a little scewed. There's absolutely nothing wrong with me physically, and when I pressed the topic she said go ahead and cycle, just avoid breathlessness (which sounds like perfectly good advice), but she sure does wish I would just walk for fitness for the next 8 months instead. This whole exchange has made me most uneasy. I will probably consult another OB for my own sanity, but has anyone out there had some experience with this?

Also, any experience or info about appropriate duration of a ride? My OB's concept of frequency/duration of exercise is 20 minutes 3x per week.

I had already slowed down considerably, and was trying to be as responsible as possible by "discussing exercise with my doctor.." But the response I got feels like a slap in the face.

[RoadRaven]

Hi there Vigg, having been pregnant before I got cycling, I can offer you no personal experience/stories.

I suggest you go to a local gym and ask them to recommend a sports doctor... or ask around a few obs/gynos...

I think calculating just by a text book may be inaccurate, but I would hesitate to offer much more in the way of advice when it yours and your baby's health at stake.

I think we have a few nurses and midwives here - hopefully they may have more specific thoughts.

Congrats on the new human you are growing too. I loved being pregnant.

[Lise]

Hi, vigg, welcome, and congratulations!

I cannot be of much help here, because I would've told you about the same thing as your doc. I'm a midwife, and I spend most of my time begging pregnant women to stop eating donuts and drinking whole milk and soda, and to walk a little, please, just walk around the block! Sigh. So I have no experience with the very fit pregnant women. RR's suggestions are good.

An exercise physiologist, trainer, or even physical therapist who works with pregnant women might have some research/info you can bring back to your doc. She's trying to give you the best info she has.

Best wishes, and take care,

Lise

[doc]

I'm always envious of pregnant women who can exercise. I couldn't do anything at all while pregnant. I would immediately puke. Do a search on this website because this topic has come up many times before. But avoiding breathlessness is a very good guide. You should avoid being anaerobic. If you remain aerobic, you should be good to go for as long as you like.

[btchance]

I'd also watch carefully to make sure you don't overheat. As far as what you can do physically, I would go with what your body feels comfortable with. For example, I had two close friends who were pregnant at the same time, due within a month of each other, and they both were horse trainers. One had to quit by 4 months because it physically hurt her. The other was riding up until she delivered.

Otherwise, I would talk to another ob/gyn. I've heard numerous different recommendations, but from my understanding the main thing is to remain aerobic (which the threshold will lower during pregnancy I believe) and to stay cool. I hope you can find the answers you want.

[RoadRaven]

bt raises a good point about body temperature.

When you're growing a new life, your blood volume increases because you are catering for the child's life oxygen supply as well. The extra blood volume raises your core temperature as a matter of course. So def watch how hot you get.

I did low impact aerobics (video/telly - 1/2hour 3-4 times a week) right up til the week 4 of my 5 babies were born. Well worthwhile from my perspective in terms of aerobic fitness during labour, as well as overall fitness for recovery afterwards.

[doc]

Oh my gosh of course. Staying cool is critical. Studies have clearly shown that elevated temperatures (1st trimester I think) significantly increase the risk of birth defects. By which they mean temps over 101. Avoiding sauna, steam room, or whirlpool use is recommended.

[Jennifer]

vigg-

Congratulations!

I just had a baby, and while my MW was very laid back and realistic about the my almost everything (sushi, traveling, etc) she also felt pretty strongly about me not overdoing the excercise. She gave me a max HR of 135. I gave up riding around 5 months because I was more concerned about falling, and it wasn't really very comfortable. I did remain really active throughout. yard work, gardening, etc.

You may find in a month or two that the HR restriction doesn't really bother you that much. I thought it was rediculous at first, but once I hit about three months, it was no concern. 130-145 was as high as I could do comfortably anyway.

[vigg]

Thanks for the input everyone. I found an OB who is also a triathlete who, I assume, will be able to speak more specifically about issues such as frequency/duration/intensity of workouts and rides, instead of just handing me the number 140 and sending me on my way. Another thing my current OB told me was absolutely NO running (why? I don't know..). I don't want to be too hopeful that this new OB will tell me everything I want to hear, but I think I can count on advice that will be more specific to my current level of fitness.
Also found a good book that I have already ordered: Exercising Through Your Pregnancy by James Clapp. It's highly recomeneded by women athletes who are or who have been pregnant, so it looks like I've managed to find some guidance.
Thanks, Vigg

[winky-girl]

Vigg: Please give us an update when you come back from the new ob. I have just started riding and am trying to get pregnant. So advice for the future will be helpful.

[ChocolatePizzaR]

I teach indoor cycling, and taught class 2 days before I delivered my second child. Riding while pregnant is certainly do-able, and I'm convinced that being fit made delivery easier.

Re: max HR... As you said, the 140 figure is out of date. Staying aerobic (and cool) is key. The catch is that everyone crosses their anaerobic/lactate threshold at a different point. For some, it may be at 85% of MHR, for others at 92% and for still others, it might be at 78%. I believe the best way to know is to pay attention to your breathing. As long as you can comfortably breathe thru your nose, you should be alright. (BUT I'm not a doctor, so please please please confirm this with him/her!)

The hardest part for me early on was keeping my intensity moderate. I didn't *feel* different, so it took conscious effort to not push myself. I had to remember that if there was anything wrong with my child when he was born, I'd always have regrets. (I know it's kind of a morbid way to think about it, but it worked for me.)

I think the "no running" thing has to do with the ligaments, but I'm not sure.

Best of luck!

[Jennifer]

you can run while pregnant.

although later it turns into more of a waddle-jog

[vigg]

The new ob said the same thing - 140 bpm max. I told her how easily my hr shoots up to 160 or so just going up a slight hill, but then plummets back downward once the hill levels off, and she said that was probably alright, but why not just lower the gear? Yes, these MD's know a heck of a lot more about human physiology than I do, but this 140 max sounds like a concrete, simplistic effort on their part to protect their collective butt.
Anyone who is as confused as I am about all this (you know, there are a number of sources claiming the 140 max is ultra-conservative bunk, but just check with the doc to be sure it's OK to exceed it, then the doc says "oh no, stay below 140...") should pick up a book by James Clapp "Exercising Through Your Pregnancÿ." I admit he seems a little overzealous about his agenda, but he does cite ample studies that refute many of the current guidelines, including the degree of danger of overheating the baby, or depriving it of oxygen. And because the body undergoes so may changes throughout the pregnancy and even during the course of each excercise session, the 140 max is almost irrelevant. Does this mean I'm going to go all out? No, but now I at least have a physiological explanation for why my heart rate shoots up so readily on hills, with no real change in my perceived exertion. I won't get into it here, but I will certainly stop worrying that I'm hurting the baby if I'm above 140 for 30 second intervals here and there.
As for conception, much of the word out there about excessive exercise impeding your ability to conceive is speculative. Exercise, for the most part, improves fertility, provided one's overall lifestyle is healthy and periods are regular. I'm an impatient person, and had assumed that maybe I didn't get pregnant right away because I was exercising too much, but in retrospect, it took us only two cycles of concious effort (if you know what I mean) to get pregnant. It just felt like forever at the time. Good luck to you!
Vigg

[Grog]

Yes, these MD's know a heck of a lot more about human physiology than I do, but this 140 max sounds like a concrete, simplistic effort on their part to protect their collective butt.

You bring up a good point. From what I heard, insurance premiums for obstetricians in the US are skyrocketing, especially in your state and California. The number of people that sue their ob. for the slightest problem around/during/after childbirth is EXTREMELY high, so maybe that explains a conservative stance on the part of many of them (even if it doesn't necessarily make sense scientifically).

[Lise]

Yup. Illinois is a terrible state in which to practice obstetrics, too.

And still, I wish more of my patients were worried about getting in enough exercise!

Good luck, Vigg--wishing you well through the whole nine months! Lise