When should you stop working out if you are pregnant? Since labor and delivery is a very intense physical event, I would say it is smart to continue working out up until the end if possible, to keep your stamina up (one exception being if you are told by your practitioner to rest, of course :) ). Even a couple weeks of skipping workouts can have a big effect on your stamina. However, I do think that workouts can and should look a bit different towards the end of pregnancy than at other times.
About midway through my pregnancy, I decided to plan to start tapering my work outs starting around 36 weeks. Even a couple weeks before that mark, I pretty much had to make them easier because I simply did not have the energy I previously did. Around that time, I also came across a number of stretches that I started to incorporate in my workout (normally I spend little to no time during a workout stretching). It worked out well because the stretches provided for more downtime during the workout, but were also productive towards my goal of getting my body ready for birth.
My last workout (which was actually just about 6 hours before I went into labor) I remember thinking to myself, "How long can I keep up exercising?! I just wanna quit!". I was battling so much fatigue that workouts were feeling like a huge chore (normally I enjoy them). I decided that night that I would keep up my 3 day a week workout schedule, knowing that I would be happy in the end that I was consistent with getting my body ready for delivery. Little did I know that would be my very last workout before little man came!
I wanted to share with you a sample of the type of workout I was doing towards the end of my pregnancy. As I have mentioned before, I am not a medical professional, and this might not be the right workout for you, so talk to your medical professional. Certainly, I would not advocate starting this kind of workout if you haven't worked out your whole pregnancy and are now at the 8th or 9th month. However, this could be a jumping off point for you if you need some inspiration and have already done similar workouts in your pregnancy so far. If you are looking to learn more, these are some resources that helped my refine my workouts towards the end of pregnancy: here are 3 exercises recommended for a strong birth and here are recommended daily stretches to help the body prepare for birth. Overall, this is similar to what I normally do for a workout, but it has more stretches, focuses more on core and cardio (almost no strength component) and avoids core exercises that put too much strain on the rectus abdominus, which can encourage the formation of diastasis recti (a split in the ab muscles that is common in pregnant women which can lead to a host of other health issues).
This workout involved some equipment you might not have at home (I was working out at a gym), but can be modified for a home-based workout. This workout took me almost an hour to do, with more rest times between sets than I normally take
10 fast walk on the treadmill
Wall sits (60 sec), side planks (45 sec each side), bridge (60 sec), pelvic rocking [aka pelvic tilts] (60 sec) - repeat 3 times
Lunges with weights (20 reps), squats with weights (15 reps), transverse tightening (20 reps) - repeat 3 times
Leg adductor machine (10 reps with a heavy weight), air squats (20 reps) - repeat 3 times
Jump rope (90 jumps), side planks (30 sec ea side), psoas release (60-90 seconds) - repeat 4 times
8 minutes on the Stairmaster, moderately fast pace (According to my personal trainer certified hubby, the stairmaster is one of the best workouts for your body. I can attest its also easily one of the hardest!)