Pregnancy Hormones 101: Relaxin....
Relaxin……What is it?
Relaxin is a hormone, released (in low levels) as part of your monthly cycle, but in pregnancy it is found in abundance.
What does it do?
It allows the smooth muscle/ligaments in your body to become lax and stretch out easily to accommodate your growing baby, and allows everything to stretch in labour so that pushing something the size of a watermelon, out of something the size of the lemon, is in fact, doable! So it’s a pretty good thing we have it!
So why do I need to know about it?
Well, relaxin doesn’t just affect the smooth muscles in the tummy, it affects the whole body! This includes the pelvis and hips. This means that caution does need to be taken when exercising, listen to your body and know what your own limits are.
Let’s get science-y for a minute for a few relaxin facts;
- Relaxin is a vasodilator, this means it allows blood vessels to relax and increases blood flow.
- It is produced by the corpus luteum in your monthly cycle and in pregnancy it is created by the placenta.
- It is strongly linked to hypermobility in pregnancy and because of its affect on the pelvic area it is linked to SPD (Symphesis Pubis Dysfunction – more on this in another post).
So whilst you may be thinking, excellent I’m more bendy now, which may be beneficial with certain activities ;) You need to exercise caution in your training. Here are a few things to think about when training:
- Avoid single leg, unilateral exercises (i.e. pistols)
Because relaxin makes the pelvic ligaments so lax, the pelvis is very mobile during pregnancy. Working on one side of the body at a time can put a lot of pressure and strain on the joints and can result in pain.
So amend these movements, do pistols to a box if they feel comfortable. If not, try working both sides together. Do weighted/bodyweight squats, squat holds, box step ups…..
- Avoid inner thigh exercises specifically. The head of these muscles are attached to the symphasis pubis (pubic bone area of pelvis) and can pull on the joint when engaged.
Instead, try using a slingshot or resistance band and do glute bridges, or side lying leg raises. This is good because it is an outward isometric hold which strengthens the outer side of the hip and balances out the tighter inner thigh muscles.
- Foam Roll:
The sacrum muscles and ligaments can actually become tight as the relaxin loosens the other parts of the pelvis and allows it to widen. The sacro-iliac (sciatic area…. Known as the top of your bum) can become painful as it works hard to stabilize the mobile pelvis. So roll out these muscles daily to ease any pain and keep you moving well enough to keep training.
Remember to maintain your stretching routine before and after training just as you would outside of pregnancy. Recommended stretches coming this week in another post, specifically for back pain in pregnancy!!
If you find yourself suffering with really painful pelvis and hips…. try sleeping on your side with a pillow between your legs, it prevents muscle strain on those supporting muscles… I do this and i am not pregnant (just feeling old).
Also, spend time in the water. All that buoyancy takes your weight and voila… a rest for the muscles. Be it in a pool or a bath.
Don’t hesitate to hit up a physiotherapist for this problem either. In the NHS your Midwife can refer you though most places not will take self referrals. In the UAE, you can try Family Medicine and they can refer you.
So go forth and train, just remember your body’s changing state and adapt your training accordingly. Consult an Antenatal and Postnatal qualified trainer to assist you if you are stuck, it’s literally their job and they know it well.
The Fit Midwife xxx