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  • Writer's pictureSophie Power

23 - 24 weeks - heart rate training and surviving the heat

23 weeks

So after Everest, holiday and a getting back to it week I feel ready to really focus. Well for 2 weeks before we have another little holiday! The issue is the weather isn’t playing ball. It’s forecast for 35 degrees all week (that’s 95 farenheit to my friends over the pond). Pregnancy is not the time to over heat so I’ve been adjusting my plan as I need to.

Running in the heat is like running up a hill – it’s harder so you have to adjust your pace! I’m learning so much from having all my training based on heart rate. Pregnancy isn’t an exact science - research hasn’t had much funding and you can’t really test on pregnant women. Which means almost all pregnancy advice tells us we can’t do something. Even if there’s no evidence we can’t – just because there’s no evidence we absolutely can. So advice often defaults to “sit on the sofa and eat cake” – which I’m pretty sure anyone reading my blog by now will know I think is the worst option for mum and baby!

So what’s out there in terms of advice on heart rate? The sit on the sofa (outdated) advice is to not let it go beyond 140bpm during pregnancy. Which would mean giving up running for me! But more recently most advice is that we can continue vigorous exercise as long as we can still hold a conversation and feel good. So no maxing out into our anaerobic zone but we can still feel comfortable getting a good workout in. Dr Stacey Sims argues our bodies can’t actually go anerobic whilst pregnant – they put a limit on us. And it feels like this is the case to me. Once my heart rate goes much above 160 for more than a few seconds something doesn’t feel right. What does feel right is holding 155-160bpm for intervals up to 5 minutes or so – I can still speak in short sentences and feel in control. I’m working hard, but I’m not out of breath. So these are my magic numbers.

Pre-pregnancy I would just listen to my body to work out my effort level but as my body changes I’m finding having these magic numbers really helpful. Giving me confidence I’m still working hard – my training is still effective – and also I’m not going into zones I shouldn’t be!

In the heat it’s particularly helpful – in the warm gym I have to reduce my pace for treadmill inclines by 10% for my target heart rate – without the data I might have pushed too hard or been disheartened that I felt less fit.

That 10% seems high so I start some research and read on the Runners World website that for every degree celcius increase in temperature above 15 degrees, pace for the same effort drops by 4 seconds per mile. So at 35 degrees that’s 80 seconds per mile! Looking at my treadmill session again today this holds true – I had to reduce my incline interval speeds to almost 12 min miling from 10.45 to give about the same heart rate. The gym wasn’t 35 degrees but unlike my home treadmill there wasn’t a fan so I definitely felt hotter.

I’m adjusting my outdoor runs too. I’m about to head for an easy run around 9.30am when hubby asks if I wanted a quick walk first. Just walking up the hill to the Downs is hard in the heat so I realise there is no way I can run!! So I switch for 4 easy treadmill miles on heart rate with the fan blasting in my face : )

Keeping cool makes such a difference to perceived exertion, even more so in pregnancy it feels. In 2016 I ran a race called Spartathlon in Greece – covering 153 miles within 36 hours (on fairly hilly road, in the heat). Every 3 miles or so there was a checkpoint where you could drink and eat but more importantly dunk your hat in cold water or fill it with ice. I quickly realised keeping my neck, head and wrists cool made my entire body feel cool and I’m using that experience in pregnancy! So I’m putting a bucket by my treadmill for my towel and wetting it before spin class (as well as getting there early to get the bike under the aircon). And I’m running as early as possible in the morning now to avoid the heat.

(the finish line of Spartathlon is kissing the feet of a statue)

I’m acutely aware of my ego in all of this and thinking of the bigger picture. I really hate to drive anywhere – I love to walk and of course its better for the environment. But I ended up driving the 3 miles to the hospital for a consultant appointment today. I can barely walk 50 metres without melting in this heat – it made no sense to spend almost 2 hours out in it walking there and back. Sometimes its just best to be sensible – pregnant or not - however hard that is for someone who loves to be active! Its lucky I was sensible though - the midwife taking my blood pressure remembered me as I’d run to her previous drive-thru session (which was rather unusual). I think if I’d run today she’d have put me on a watch list!

Controlling my ego in a group session is a harder task though – as is listening to my body when the adrenaline kicks in. This week I have my first spin class back and whilst my legs and lungs say go for it, my heart rate creeps above the magic 160 in longer intervals and I decide to pull back. It’s so hard when everyone’s wattage is on a big screen and my max is way off what it would be pre-pregnancy but I’m just conscious to think of the bigger picture. Without the need to recover so much between intervals I still end up with the highest totals though 😉 (apologies to all the guys in my class…. I promise I’ll slow down soon!).

It’s easier than I expected to watch a 100 mile trail race without any FOMO though! The Centurion Running North Downs 100 mile is an amazing race and I’d probably have been running it weren’t for being pregnant. I live a couple of minutes run off the route so it’s a local one and a beautiful course (as well as being fantastically organised). I decide to do my 10 mile run early to see the runners (and survive the heat myself). They had started at 6am and I pick up the route when they are about 12 miles in. It’s already hot by 8am and the humidity is sapping everyone’s energy. Runners look like they’ve done closer to 50 miles already, heads hanging and moods low. I can see why – I’m only running 10.30 min mile pace but it feels like I’m running 9s! This is one day I’m happy not to be racing! In fact I think my competitive drive for this pregnancy has now gone. I’m putting on weight much quicker now -4lb in the last 3 weeks and my bump is expanding nicely. I won’t be making any more gains, and will be unlikely to hold this level of fitness. But I’m really happy with where I am. It’s just about minimising the decline from here!

I've been asked about my training plans so here's what my week looks like - mostly worked around my diary and how I feel but it's usually 3/4 runs - 1-2 easy, a treadmill incline interval one and a long one. Then boxing (which is half circuits) and spin classes and 2 strength sessions.

24 weeks


What is still getting in my way is tiredness. The promised second trimester bounce has clearly missed me and I’m frustrated about my lack of productivity. I am just so tired in the evenings I can barely function – even just to put furniture ideas for our new home on a pinterest board! Evenings are my admin time – to run the family, the house project, to catch up with friends, to write and research. Much of which isn’t getting done. With extra sleep and couch time I reckon I’m losing 2 hours a day so I need to work out how to commit to 2 hours’ less stuff!

One thing I’m trying is taking more control of my energy to see if I can get any of that 2 hours back. Foodwise I’m starting the day with a green juice (also helping on the hydration levels) and focusing on getting more fruit and veg in by making sure I have some at lunch as well as dinner. No cheese toastie without a side of salad! Now I’m not feeling sick anymore I really have no excuse not to take more control of my diet – and late night ice cream can’t be helping me sleep well (especially as it wakes baby up for a kickfest). I’m also taking on extra salts and focusing on hydration at the moment with the heat. I find it easy to forget to drink outside workouts as it can feel a bit of a chore but if I’m teaching my 5 year old that he needs to drink so his pee isn’t yellow I should be monitoring mine too!

Sleepwise I’ve set one of those bedtime alarms. If I’m not getting anything done past 10 at night I should just go to bed – having prepped the school bags for the kids so I can sleep until they wake up. Hubby is happy to help nudge me on this one as he just wants to be left in peace to watch Marvel movies. I think he uses our Disney+ subscription far more than the kids…

Aaaarrrrrggggg another classic pregnancy symptom hits – the dreaded acid reflux. This occurs as relaxin relaxes all of our muscles - including those in our esophagus which stop stomach acid coming back into the throat. Relaxin is clearly not that smart. I didn’t have it at all in my first pregnancy and only very late into my second (around 7.5 months) so am wondering whether I have more relaxin this pregnancy (which might explain the early pelvic pain?) or it’s just more badly targeted. Either way it’s not fun and I’m missing my morning cup of tea!

I'm not helping myself though as I'm making full use of the Eat Out to Help Out Scheme (50% off food Monday-Wednesday) meant to encourage us out of our COVID shelters at home. Hubby and I are popping to town for cut price lunch each day and the richer food is not helping matters! On the plus side my gym has half price protein smoothies which seem to be reflux-friendly so I’m treating myself (though I have had to draw the line at just popping in for a smoothie and not a workout…)

The weight is starting to pile on quicker now – I’m 13 pounds up (some of that might be the 3 pizzas I’ve had this week though – I have crazy cheese cravings!). I now notice my bump all the time and it has started to get in the way. I manage to catch it on the bike in spin class by accident, forgetting I need to sit upright. My instructor found it rather amusing so has decided to remind me each time not to go into racing position when the rest of the class do. I’m bending my arms slightly on kettle bell swings to avoid the bump and downward dog stretching is definitely out for the acid reflux side effect but most of my weight training is unchanged for now.

I am feeling a bit swollen and heavy “down there” today which I make a note of to mention in my mid-run midwife appointment. Unfortunately I’m not sure I should have bothered. My appointment takes no more than 5 minutes, even though I’m fairly sure they are booked every 20 minutes and she’s running on time. She does a quick check of my blood pressure and baby heartbeat, books my next appointment in a month’s time then asks if I have any questions. I mention how I’m feeling and her quick response is that I need to not stand up for too long or lift anything. That’s it. No examination, no follow up questions, no thought for what the side effects of her “treatment” might be. I’m just shown out of the door.

If I was in my first pregnancy I’d probably start cutting right back on any exercise and stop my strength training. I’d be panicked I was doing real damage to myself or my baby. I’m grateful I have the confidence in my body that this doesn’t make sense – not without really working out whats going on.

There are so few touch points when you’re pregnant so each is such an important occasion to support the mother through her journey. Now there are so many amazing midwives out there – one of which I had last pregnancy – who treat each mother as an individual, sharing all their advice and encouraging mums to share their concerns. But I haven’t been asked once about my exercise or health in this pregnancy. Not once about my diet or weight gain. Not once given any positive advice to do better for my baby, just to check I’m not smoking, binge drinking or doing drugs. Maybe its because I’m in my third pregnancy she thinks I know what I’m doing now? That I don’t want to be lectured? Or because I don’t have any red flags on my file I can safely be left to drift through pregnancy?

I just hope first time mums don’t have the same experience. As a first time mum I didn’t know what questions to ask! – so it’s important medical professionals are active in giving support, though I’m aware they are stretched and working with new practises at this crazy time. I understand it’s hard to get across so much information in a short appointment and decide what is important – especially when you are usually meeting the mother for the first time. But we really do need to look at antenatal care in this country and ensure every mother is fully supported. Anyhows, rant over. As you might imagine I’m going to ignore her default advice to sit on the sofa and go and see my womens physio Emma to see what she thinks.

Luckily my appointment is mid-run so I ease off my frustration on the run home! Running is going really well this week. I had a fairly brutal incline treadmill session set with 8 minute intervals running at 10% incline but I just adjusted the pace to hit my heart rate target of a 160bpm maximum. I’m not sure I would have had the endurance a few weeks ago for this – somehow it feels like I’m getting fitter – or certainly stronger.

My long run (broken by that midwife appointment) is 9 miles easy which I do almost all as laps of the local park on the soft ground (we finally had some rain). I find myself thinking more about my running style – I’ve been exchanging a few emails with Shane Benzie ( who last year reviewed my technique and gave me ways to improve. He’s a movement specialist and has just written an amazing book about, well, running. So I’m trying to focus on running taller, which really seems to help my back and breathing – I need all the internal space I can get to fit baby in over the next few months so have to start practising now!

Last pregnancy I’d given up running by 22 weeks and here I’m still going strong at 24. With Cormac I had quite a bit of hip pain (not pregnancy related – I just never stretched enough) and with UTMB in my sights I wanted to protect my pelvic floor during pregnancy for a quicker recovery afterwards. [Note that was not driven by any medical guidance I just reckoned it might be the case]. So any runs I can do now really are gifts and I will embrace them no matter how slow or short they are.

I end the week being interviewed by Esther Newman, editor at Womens Running Magazine for their new podcast – all about ultrarunning, pregnancy and of course pelvic floors. We end up nattering for another hour afterwards, debating what needs to be done to support women in their running journey and how we can help. It’s become a personal crusade of mine to help other women – whatever their age or sporting goals. Part of it is through working as at trustee at Women in Sport but part is just trying to share my story and experiences honestly. It feels rather strange being so public about my life and this pregnancy – just 2 years ago I wasn’t really on social media! – but I’ve received so many messages and positive stories about how it has helped others. So I’ll just keep going!

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