As I write this I’m just weeks away from delivering my third child. I’ve run through all of my pregnancies to varying degrees and because I know how hard it can be to find reliable information on running while pregnant I want to share with you what I’ve learned over the 26 months of my pregnancies.
So today I bring you the first of three installments of my guide to running while pregnant. This post chronicles the first trimester and tells you what you might experience with your running during that period.
Because every woman’s pregnancy experience is different, I know I can’t cover everything and might miss something important to you. I encourage you to ask questions and offer suggestions for other topics to cover. And as always, if you experienced something different or disagree let us know that too!
Now on to The First Trimester!
Weeks 1 – 4 (Blissful Ignorance)
The first two weeks, you’re technically not pregnant. You are getting ready to ovulate and then ovulating. But around 2 weeks in, fertilization occurs and the little zygote starts burrowing into the uterine lining and starts to release some exciting hormones. You probably won’t notice anything different, unless perhaps you race or do a really hard effort during this time.
I ran a marathon when I was unknowingly 3 weeks pregnant with my second child. I could not for the life of me understand why I was running so much slower than the pace felt. I thought for sure I was running around 7:15, but was running more like 7:30+ over the last 10 miles. When I was about 4 weeks pregnant this time, I did a speed workout and my lungs burned at a pace that should have been more than doable. I thought I was just out of shape from taking time off to nurse an injury. I was wrong!
Once implantation occurs, those hormones trigger your body to make more blood, which in turn taxes your cardiovascular system more than normal. But it’s a subtle difference in those early weeks and probably only detectable when we’re really pushing ourselves.
My training logs for my first month of my 3rd pregnancy:
Weeks 5-9 (OMG! I’m Gonna Die!)
This is when the fun really starts! At 5 weeks you might feel a little extra breathless on the run – it might be hard to hold a conversation with your running buddies as you huff and puff.
If you are one of the lucky ones who experiences morning sickness, (which is in reality all day and night sickness), it will likely hit you between weeks 6 and 8. If you make it to week 8 and still feel pretty good, consider yourself one lucky lady! Morning sickness is no joke. Besides the constant nausea and bizarre food aversions (I seriously ate next to no fruits or vegetables for 3 weeks this time. Gross!) you might also suffer from very severe exhaustion.
While the baby is a mere speck at this point, the hormones are wreaking havoc on your body.Your body could probably run pretty close to your PRs right now, if somehow you felt like doing it. But it is really hard to muster up the energy to get out of bed, let alone get out the door for a run, let alone run hard!
And there’s something else that makes running difficult during these weeks: you might be experiencing anxiety about miscarriage or something going wrong with the pregnancy. It can feel scary to push yourself physically when you know such a fragile process is going on inside your body, and it’s hard to justify that track workout when the speck inside you is so dependent on you taking care of yourself. No matter what any doctor or book says, no matter how many friends-of-friends ran 10k prs at 6 weeks pregnant or continued to run megamiles, it’s all different when it’s your health and the health of your baby at stake.
For me, all physical signals said STOP. LAY IN BED! And it was hard to ignore them with motherhood on the line. That being said, all scientific evidence points to exercise as being not only not harmful to the developing embryo, but also downright good for both of you.
Every day is different. One day you might not be able to get out of bed and the next you might feel like busting out a track workout. Take each day for what it brings you and roll with it!
How much you do during these weeks is up to you and your doctor. You needn’t worry about overheating (unless you’re running in some crazy hot weather) or how high your heart rate is. The main thing is to stay hydrated and stay within an effort level that feels comfortable. That doesn’t mean you have to run easy 24/7, but when you do push it you probably want to avoid running so hard you get out of breath, nauseous or need to bend over with your hands on your knees after intervals. I felt good keeping things at about a tempo effort when I did workouts and races during this time and throughout my pregnancy. I did several track workouts during the first trimester and was about 1:00/mile slower on 800’s, etc. and I also felt like 2 – 2.5 miles of intervals was about all I could handle, when I usually did 3 – 5 miles of intervals when not pregnant.
Especially during this month, every day is different. One day you might not be able to get out of bed and the next you might feel like busting out a track workout in between going to work and cleaning the house. It’s weird how bad one day can be and the next day is not so bad. Take each day for what it brings you and roll with it!
My training logs for my second month of my 3rd pregnancy:
Week 5 (no log, but according to daily mile I ran 50 miles before finding out I was pregnant at the end of the week!)
Week 6 (no log again, but managed 47 miles)
Week 7 (no log. Fell off the cliff: 35 miles)
Weeks 10 – 13 (Feeling Alive Again)
As the first trimester winds down you will one day feel sudden relief from the morning sickness and the fatigue. For me, I typically felt one level better around 10 weeks. During this pregnancy I had a horrible puke-filled day at 10w3d, but on 10w4d I felt good enough for a 4th place finish in a local 5k and haven’t puked since.
By week 12, I felt good enough to start running a little more all three times. This third time I ramped all the way back up to 45-50 miles per week around week 13 and held steady until about 20 weeks! Also, the risk of miscarriage goes way down once a heartbeat is detected after 10 weeks. As a result, your anxiety will probably ease up and make running more enjoyable in that regard as well.
This is the beginning of the good times of the pregnancy when running usually feels pretty great.
My training logs for my third month of my 3rd pregnancy:
Want more? Read our 2nd Trimester: What to Expect from Running When You’re Expecting
What was your experience running through the first trimester? Did you experience morning sickness? Do you have any questions or concerns about running during the first trimester?