After some trial and error, and speaking to various professionals and athletes, this is what I’ve learnt:
1. Control your heart rate
The unanimous advice I’ve had from every physiologist is to cap your heart rate at 20% below your maximum (~175bpm for me). I’ve been following guidelines to stay well below this during the first trimester, while the neural tube and other important parts are being formed. Now that I’m in the second trimester, I’m aiming to spend a little more time each week at the top end of that limit. The aim is to make sure that I don’t have too much of a break from high-intensity work by the time I’m back riding normally. My favourite pregnancy-friendly session so far has included a short hard effort (5-10s) to get my heart rate up to around 170pm, then 3 minutes at low power but holding a high heart rate. The number of reps depends entirely on how I’m feeling that day. It takes some practice to pitch it right, but as soon as it looks like my heart rate is rising too high or too quickly, I stop.
2. Little and often
When I first found out I was pregnant, I naively assumed I would be able to keep up with 20 hour training weeks until I had a bump getting in the way. Two weeks later, I could barely get out of bed. Not being used to achieving so little, I would use the good days to try and make up for the bad. I’d train for as long as physically possible, then wonder why I needed 3 days off to recover! I’ve since learnt that little and often works best for me. I aim for at least 1 hour of exercise (riding, walking, swimming) per day. My longest rides are around 4 hours, but usually with a planned stop to break it up a little.
3. Eating for 1 and 1/8
My nutritionist informed me that my 45g foetus, amazingly, does not require the same amount of food as a fully grown adult. Eating for two would be a lovely perk, but in reality, I only need a small amount extra, particularly early on when the baby is so small. However, what pregnant women do need more of is carbs, especially around training. Now I always make sure I bring more riding snacks than I think I’ll need and put an energy drink in my bottle, even if I’m only riding for an hour.
4. Pee stop planning
The Rapha bib tights with a buckle at the back for rapid pee stops are a lifesaver. Trust me on this one.
5. Be flexible
Make a vague training plan for each week, but allow for plans to change considerably. I’ve had weeks where I haven’t completed half of what I wanted to, and others where I’ve pleasantly surprised myself and exceeded my goals. I’d been promised that the second trimester would be this glorious period of time in which I’d be radiating energy and would have the strength to lift a car if I needed to. I remember waking up one day at around 14 weeks and thinking “wow, I don’t feel terrible today. This must be it!” and I got busy planning a return to normal training immediately. This lasted about 48 hours before I was back on the sofa feeling sorry for myself for a day. Somebody explained to me that random days full of fatigue are likely because the baby is doing some serious growing, so listen to your body and give it some rest when it asks for it.