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Triathlete Blog

First Trimester Fitness

By January 22, 2010July 20th, 2015No Comments

Last week I talked about exercising through pregnancy – the why and the how. And also the changes that you and your body will encounter. I’ve now gone through an entire trimester of this thing called pregnancy. How did it go?

Disclaimer: I am not a doctor nor should my experience be construed as medical advice. Talk to your physician about guidelines for exercising in pregnancy.

The first trimester is 13 weeks of pregnancy. I found out I was pregnant in week 4. You may or may not know this but it’s worth explaining that by the time you miss your period you are already 4 weeks pregnant. You are not actually pregnant the first 2 weeks but since most people do not know the exact date conception occurs, pregnancy is counted from the start date of your last period. Looking back in my training log, it was pretty evident something was going on in week 3 because I went for a run and my heart rate was sky high compared to the pace. A week later, I realized what was going on. And started making changes to my training routine.

Someone asked if my doctor gave me permission to workout. Unless the doctor needed to restrict activity level because of a high risk factor, it seemed to me like the doctor was not otherwise going to be much help in giving guidelines for activity. In most cases, you do not even see the doctor until after 10 weeks. Some doctors do a consultation around 6 weeks but the first visit is usually around 10 to 12 weeks. At that point, you’re almost finished with one-third of your pregnancy! And, those are the most critical weeks for development. You could do a lot of things right, and also a lot of things wrong in that time. Bottom line: you have to take responsibility to educate yourself. Read books, look through websites and ask other athletes. Then, filter the information to make decisions for yourself.

During the past 13 weeks, I did some type of a workout on all but a few days. It’s important to go into pregnancy with the expectation that you will keep on doing what you do – just modified. When you start giving yourself permission to sit on the couch and skip workouts it becomes a slippery slope. Yes, you will be tired. Yes, you will be slow. And, yes, you will need to make some changes. But I never finished a workout regretting that I started in the first place. I always felt better at the end.

Here are 3 guidelines that helped me get through the first trimester: (1) Do your workout early in the day. From what I experienced, fatigue hits like a pile of bricks most days after 2 pm. Workouts after then will not happen. (2) Something is better than nothing. Even if you only have the energy to spin on your bike for 20 minutes, you will feel better. (3) Keep on keeping on. Keep expecting yourself to be who you have always been. If you have always been fit – you will continue to be so in pregnancy. Like you’ve always done, make the time for it and expect it from yourself.


In the first few weeks, swimming did not feel good. I had to switch all of my asthma meds and I noticed it most in the pool. Masters had also just started up – and I was feeling a love/hate relationship with it. I love swimming hard. I busted my ass last year to move up a lane in masters. Now, I could barely keep up. I hated that. Plus for the first few weeks I didn’t want to say anything about being pregnant. It took about 2 weeks for my lane mates to figure it out and once they did I got a lot of flack for pulling the pregnancy card (which incidentally can be pulled for just about anything). On days when I felt good, I might pick up the pace for some 50s or 25s. But I would never go hard or sprint. Nor did I do anything that involved holding my breath. No diving or jumping either. I did, however, do lots of pulling, paddles, kicking, fins, IM (I totally mastered the art of easy fly) and yes you can still flip turn.

When I did go to masters, it was so hard to just sit in a draft and not compete. So I started swimming alone more and found I really enjoyed it. I could go as slow as I wanted. I could do what I wanted. There was no keeping up or explaining to do. I could also swim in the kiddie pool which was kept at 82 degrees (for some reason my tolerance to cold water got really bad those first few weeks!). As I got more pregnant, I started swimming more, and swimming felt better and better. I did tons of kicking and lots of IM just to challenge the muscles in different ways. I didn’t time myself – but by week 12 when I occasionally looked at the clock I noticed that my 200 pace had dropped by over 30 seconds. And that is why I try not to look at the clock!


Biking has been on my trainer – of course, dead of winter here. The first few weeks I felt normal on the bike. My heart rate was a little elevated but I could still do a normal workout and actually put out normal watts. And, yes, I still use my tri bike and it still has a Power Tap on it. I wrote myself bike workouts so I always had a purpose – big gears, low cadence, high cadence, little “intervals” to mix things up. I also did a lot of on the bike work mixed up with off the bike strength. This helped me to break things up because I realized I just might be on my bike trainer for the next year or more!

Around week 10 I started noticing a drop off. My heart rate was going down and so were watts. I knew it would happen towards the end of the first trimester. You will lose some strength in pregnancy and your heart rate will go down. It was interesting to track, though, because as I physically started feeling better (less nauseous, less tired) my body was actually able to put out less work. It was interesting to see the changes finally setting in to my body. If anything, you will be absolutely awed by what is going on with your body – but more importantly what you still can do while most people are expecting you to just sit on the couch, eat and make a baby for 40 weeks.


The best way to describe running in pregnancy is like running at altitude. You know you have the fitness but the breathing capacity is just not there. I would be running with my heart rate low but it would sound or feel much more labored. Part of it is because you have not caught up to the changes in your blood and heart in the first trimester.

I decided to do a lot of my running on the treadmill (two words: bathroom upstairs). During weeks 5 to 7, my easy pace stayed the same as pre-pregnancy. By week 8, it had dropped about 20 seconds per mile. After that, it was a full 30 seconds per mile slower. Though it felt slow, I thought about it – my heart rate was in zone 1 so it wasn’t that slow really. It was just that I was used to running faster and now every time I ran it was like doing an easy recovery run – every.single.time. By week 12, I was a full 1-minute per mile slower than where I started (yet my breathing had gone back to normal). The hardest part was biomechanically running like that. Every runner knows their body has a default pace where they feel most biomechanically efficient. Running nearly 90 seconds slower than my default pace was hard on the body. I could only do that pace for about 45 minutes before I started to feel wrong.

Strength Training:

Early on, I was reading through a book called the Girlfriends Guide To Pregnancy. I’m sure it has some high points, but I read two things in it that scraped my pregnant core.

1 – There is no point in exercising because you are going to get fat anyways.
2 – Have you ever seen a pregnant woman with buff arms?

Dear author: You have never seen me or any of my athletic friends.

I strength train 2 to 3 times a week, never for more than 30 minutes at a time, never with heavy weights. You cannot grow stronger in pregnancy – but you can maintain your strength. The first 10 weeks I did not have to make any changes to my strength routine. By week 10, however, I noticed changes. Push ups were as “intense” as running according to heart rate. Lunges while holding the TRX also shot my HR up. I also had to make other accommodations – and knew more were to come. By week 14 you should not perform anything on your back (or supine position) because of the risk of lack of blood flow to the baby.

Many times I mixed in the strength work with the other work. I might run 15 minutes on the treadmill, hop off for 10 minutes of strength then go through that 3 times to keep workouts interesting. “Interesting” is the key – pregnancy can often feel like a monotone pace that you are stuck at. Mixing in strength work, writing creative “workouts” goes a long way – trust me.

How Long Is Too Long:

I kept workouts at 30 to 60 minutes. Sometimes I did two workouts a day but never for more than 75 to 90 minutes total. My thinking was that I would get the most “benefit” from keeping workouts short but frequent to keep feel for the sport. There was no point in slogging away at a long and slow pace. I was going to be slow enough as is! I know many women go much longer and it works for them. For me, I liked the short stuff, especially short runs – as in 30 minutes at a time. This meant I could run more often in the week and it was a blessing for constipation let me tell you.

Using a Heart Rate Monitor:

Yes, I did. Not because I was worried I would push hard because the heart rate monitor is a window into your body. You can tell when you are getting tired and dehydrated. You can tell when something is no longer safe for you. I used it with biking, running and strength training. While I did not follow the 140 bpm guideline (which is not really based on anything conclusive in the first place), I did make my own guidelines for biking and running for heart rate and felt more comfortable sticking to them. The only thing my doctor did say about working out was to ignore my heart rate and keep workouts conversational. She said that to me when I first met her – at 12 weeks pregnant.

Overheating & Hydration:

Overheating is a risk for the athlete in pregnancy. Some athletes use a rectal thermometer to be sure their internal temperature does not go above 101 degrees. If it does, there is an increased risk of birth defects in the first 9 weeks. I had two fans going on me at all times when exercising indoors. You also need to hydrate carefully. I normally drink a lot but was amazed at how much more I needed to drink when pregnant.

Eating For Fuel:

I read that the active athlete during pregnancy needs up to 800 more calories per day (compared to the 300 calories a day most women need). Of course, this depends on your activity level. The bottom line is that if you are going to continue to exercise in pregnancy, you need to remember to replace those calories you are burning. You do not exercise in pregnancy to burn calories – you exercise to stay fit and feel good.

Body Image & Weight Gain:

This is probably the hardest thing in pregnancy. You are exercising, you are eating right and you are…gaining weight! I am currently at a weight that I have NEVER been at in my life. For an athlete, seeing the numbers on the scale move up and up and being able to do nothing about it can be disconcerting. That’s just me being honest. But, at the same time, who cares. I mean, really. There are much bigger things to worry about in pregnancy than “oh my god I am so fat!” Please, get over yourself. I just keep telling myself that you have to give something up to get something incredible in return. There is a cost. That cost will be a few pounds. In terms of costs, that’s really NOTHING! You’ll read a lot of analogies about being pregnant – some compare it to renting out space. I liked that one, and agreed that my body is for rent for 40 weeks. And when that lease is up, I will get it back because I want to. Not because it will be easy or because I expect it but because I WILL WANT IT BACK that bad.

Remember Your Reasons:

As I was running around the indoor track the other day – at my pregnancy pace – I thought to myself about how awkward it felt to run so slowly but how awesome it was that I could still do what I loved – I love to move, I love to be fit. And that is all that counts. Before you embark on fitness in pregnancy, remember your reasons. If you are in sport because it’s a diet plan or permission to eat to without restraint, you might struggle with fitness in pregnancy. In Racing Weight, the author explains how those who participate in a sport for weight loss reasons are less likely to enjoy it and stick with it. It’s when you focus on the other benefits – health, social, fitness – that you are more likely to reap the rewards. Staying fit through pregnancy is the same thing. You will gain weight, you will get slow, you will be lifting weights with your belly popping through your shirt and think to yourself I look ridiculous!True, there is no pay off in terms of dieting or body image. However, the pay off in other terms is huge. You will gain less weight, you will stay healthier and your baby will be healthier. For as awkward as it feels to run slow, the benefits to me are worth it. My reasons for being involved in sport have always been about the movement, pleasure and fitness – and through pregnancy that will not change.

I am now into the second trimester. I no longer get up in the middle of the night to pee (AMEN!) but I can’t say that it has been a total relief of pregnancy feelings. So far, I have had a headache for four days straight…I thought this was supposed to get easier for a few months before the bottom really drops out? Ironically, the only thing that makes my headache go away is running or biking.

Keep on keeping on….