For my husband and me, choosing to become parents was a decision that we took our time warming up to. As soon as that pee stick showed off its double racing stripes, a whole whack of other choices begged for our attention. I quickly fell down the rabbit hole of books, forums, websites, and of course the advice of medical professionals. They helped guide my way on everything from what foods to eat, to understanding the endlessly weird symptoms I was experiencing, and provided mouthwatering explanations of our baby’s growth all the way from “poppy seed” to “watermelon.” But as a mountain biker, I felt like there were a few burning questions that no amount of Googling could satisfy.

Of all the choices I made, riding is one I would choose again and again. My doctor, who isn’t a rider, asked me not to because of the risk of falling. The mountain biking mamas I talked to said their doctors were supportive. The internet said not to let my heart rate go over 120bpm … and then the next week I read 150bpm. With so much conflicting information, I decided to stick with the parenting advice that has resonated with me throughout my entire pregnancy, whether reading about delivery, breast feeding, or self-soothing: “You will know what to do.”


I am a confident rider. I’ve been racing mountain bikes for over a decade, and am used to spending long hours training during the week. I know my limits, and I know my weaknesses. After carefully weighing these factors, I decided that yes, I should absolutely ride. Exercise while pregnant is really important for both moms and babies, but for me, it was really hard to do. In the first trimester, I was tired, nauseated, and most often found pouting on the couch. But one day, I rallied, and carefully went for a spin while trying to remain hyper-conscious of everything I was feeling. It felt good. For the first time in a couple of weeks, the nausea went away. I felt clear-headed. I felt like myself. With so much changing—and about to change—the mental benefits of riding became just as important to me as the physical.


With a baby on board, I think it’s wise to make a few changes that will help you keep at it, but keep the risk to your little one as low as possible. For me, that meant leaving my heart rate monitor at home—I knew my heart rate would be unfamiliar to me with all the new blood circulating for two and my oxygen supply being diverted to more important things. But if I went by rate of perceived exertion, I could keep myself in check easily: if you can’t have a conversation, pull it back. I also resisted logging into my Strava account or other metrics apps—you don’t need to know down to the second how much longer it takes to get up that hill. Just get up the hill.

Ride with a Friend
Once I’d left my gadgets at home, I found the perfect replacement for my regular training buddy, Garmin, was the company of a friend. If I wound up needing help on the trail, I wanted to make sure I had someone I could count on. The other benefits are that “mommy brain”—or the tendency to forget things—is absolutely a real thing so more than once, I had to ask to borrow a gel or tool that somehow didn’t make it into my pack. Having a few riding friends I could rely on also made sure that I kept at it. It wasn’t until the second trimester that I had the energy to ask them to go for rides rather than just wait until someone asked me. My husband also turned into a new riding buddy, which was very special to me—he is new to mountain biking so not only did we find our paces had met in a mutually beneficial range, we found a whole new way to bond, and an entire new avenue for family fun in the future.

What to wear?
The other benefit to having a riding partner in your home is that you have twice the wardrobe to choose from. Thanks to a Bellaband, I was able to stay in my own chamois and baggies for the entire time I continued riding. Jerseys and my pack on the other hand became a tight squeeze towards the end of the second trimester, so my husband’s came in handy.

Should I adjust my bike?
Some moms who rode longer than I did installed riser bars or stems on their bikes to help keep them more upright. One mom I met was just finishing her weekly workout as the coach of the local high school team. She was decked out in her husband’s kit (with maternity cycling shorts underneath), had raised her cockpit a little to make room for her belly, and she was just three weeks shy of her due date. Since I didn’t ride that long, my geometry kept working for me, but I did have to remember to reset my suspension settings and tire pressure every week as my weight increased.


Watch Out For Relaxin
In addition to the risks associated with not exercising—in fact it’s recommended you exercise moderately for at least 30 minutes every day—there are a few things to keep in mind before you saddle up. First of all, the unintentionally-hilariously named hormone relaxin is now coursing through your body. It’s there to relax your muscles and ligaments to prepare for all the expansion coming your way which is good. But it also makes it easier to pull a muscle, or strain a joint. So easy does it—this isn’t the time to get a head start on your base miles, sign up for a race, or chase down QOMs.

Don’t Overheat
Next, you’ll want to keep an eye on the weather. Especially in the early months, it’s important to keep your core temperature down. Riding when it’s too hot out, or wearing too many layers for the temperature could put your baby at unnecessary risk. You’ll also have to quit your hot tub habit throughout pregnancy.

Stay Conscious
Related to this, keeping your pace at conversational levels will help keep your core temperature down, and also make sure your blood flow is not leaving you light headed. Your body will take care of your baby first, sending all oxygenated blood there, even before your brain, so make sure you’re not putting both of you at risk by going so hot and heavy you feel like you could faint. Keeping your glycogen stores up is also an important part of staying conscious, though I chose to give up my caffeinated gels and chews since some studies show too much caffeine can inhibit your baby’s growth.

Stay Hydrated
You’ll also want to make sure you’re staying hydrated, even more than before. The water you drink helps keep your amniotic fluid levels up, which is what protects your baby from the outside world. Try to drink at least a bottle every 45 minutes, with plenty before and after as well (and even more if it’s on the warmer side). Get used to frequent nature breaks.

What If I Crash?
Finally, the risk that keeps riding on the “not recommended” list is the chance of falling. This one is tough to argue—we’ve all had our just-riding-along moments. But keep in mind your baby is well-protected by a double water balloon effect thanks to your strong, muscular uterus and the amniotic fluids you’re keeping topped up with good hydration. In fact, it’s not until about week 33 that the amniotic fluids take up less space than your baby. On top of that, until about month five, your baby is surrounded by your pelvic bone, adding another layer of protection. Don’t forget to add in your own skin, abdominal muscles, and fat. It would take a fall that causes serious injury to mom to even begin to put the baby at risk.

Of course, the longer you ride in your pregnancy, the greater the risk of falling or losing your balance, even off the bike. It’s a fact of your changing centre of gravity. Further complicating this risk and defying all biological explanation, one of the symptoms you can look forward to as your pregnancy progresses is increased clumsiness.

If you do take a tumble, either on the bike or off, be sure to let your doctor or midwife know. You should feel your baby moving by about 30 minutes after a crash-free workout (sometimes exercise can lull them to sleep), and take note of any change in discharge, spotting, or resultant bruises/soreness.


You’re In Training
Exercising during pregnancy comes with many benefits. It is not a nine-month invitation to put your feet up because you’re headed towards the biggest athletic event of your life: a 6-20 hour marathon of intervals using the most powerful muscles in your body, and every ounce of your mental strength. That’s why riding was important to me—until I was pregnant, I only rode. I didn’t have a running habit. Hiking wasn’t for me. I don’t have access to a pool. And besides, I’m at my most efficient and confident when I’m on the bike.

Slow, Steady Weight Gain
Riding also helped keep my weight gain slow and steady. That’s healthiest for your baby, and it reduces the risk of gestational diabetes or preeclampsia. Not to mention, it also minimizes the risk of stretch marks.

Increased Energy
From the couch, it felt like my eyelids weighed five pounds each, and a sleepy fog clouded my entire head. From my bike, I felt almost weightless. I was chatty, laughing, pain-free, and feeling nearly symptomless. The feeling lasted for hours after I got home.

It Takes A Village
Riding also helped me stay connected to my friends and community, and that helped me stay happy and less frazzled as I slowly processed all of the many changes coming our way. It’s easy to stay at home and bury yourself in pregnancy books and worries. But it’s one thousand times more rewarding to get outside, breathe in the fresh air, and get excited for the day your little one is riding along with you.


As always, mountain biking should be fun. If it’s not, maybe it’s time to make some changes. My last ride pregnant was in week 28 (about halfway through month 7). I was the leader on my regular Friday morning group ride, but I was having trouble keeping up. I made errors I wouldn’t have the week before, and I could never figure out exactly where I should be on my bike because my centre of gravity always seemed to be in a new place. Rough trails were bothering my protruding belly, and it was tough to pedal without kneeing my baby bump. I spent more time worrying about what could go wrong, than enjoying the sunshine and the company of the group.

When we got back to the parking lot, I lifted my bike on the rack and with a great sense of certainty, I acknowledged that would be the last one. I wasn’t sad about it, and I wasn’t second guessing. It was a calm feeling telling me it was time to hang it up. I was even excited because it felt like I was just a little bit closer to being a mom, and I was ready to be in that place.

You’ll know, too. I’ll be honest, when I heard that particular advice, I found it hugely unsatisfying. I am one of those people who usually second guesses everything, and I didn’t fully trust myself not to push a little too far. But they were right. When you know, you know.

I had a lot of fun riding through pregnancy, and I’m grateful I had the support of my husband and friends to continue. I also found I connected to my sport in whole new ways. I did my first overnight bike-packing trip while I was about eight weeks along. I indulged in the convenience of a shuttle ride for the first time at week 11. And I rode a fat bike in the snow for the first time at 24 weeks. I learned to take my time (and more pictures), reflect on what riding really meant to me, and to others. And I got to imagine what riding will mean down the road when we go as a family. If you choose to ride throughout pregnancy, I wish you the happiest of trails.

Disclaimer: Kristen is not a doctor and recommends you talk to yours before bringing your own “baby on board” while pregnant.

Author Bio

Kristen Gross is a Canuck in Cali—she arrived in 2013 to the land of “always summer”. Before becoming a first-time mom in 2016, she raced XC in the pro category with career highlights including a fifth place finish in the BC Bike Race. Kristen is also a mountain bike skills instructor, sales rep for Rocky Mountain Bicycles, and runs her own freelance writing/communications business.