It's not so they can stretch and work out. Photo / Getty Images
Large increases in "athleisure" (street/sports clothing) sales are being seen around the world - a trend most welcomed by the mums of today, who have been using Lycra to cover up the perils of the daily grind for years.
But behind all those bright coloured camel toes lie many reasons why you see so many mums wearing Lycra.
1. You're basically a professional athlete these days anyway
A simple outing to the park or to the supermarket can result in a sprint session across a car park or down an aisle, a climb to the top of a rope ladder to retrieve a child that could climb up but not down, or some other sort of unexpected wrestling event on the ground.
Unlike the pretty summer dress or shorts you might have worn in your previous life, Lycra is not going to reveal your bum or boobs unless something has gone very, very wrong with your purchases or the strength of your child.
Kids are obsessed with bums and boobs and poos and wees. Even just standing around with your child can result in a hemline being lifted too high or a neckline pulled too low as your child points to some previously private body part to ridicule you in public.
Lycra doesn't move when you move and it won't reveal bits of you that you don't want other people to see. Hell, you don't even want to see those bits yourself anymore.
3. It dries quickly
Sometimes you need your clothes washed multiple times a day. But that's not going to happen. With Lycra, you can just grab a wet wipe as you drive and hope that whatever was smeared on you will be off and the wet mark dry before you get to your destination.
4. It's hard to stain
Note that says hard - not impossible. Kids find a way to do even the most difficult things. You've learned the lesson. Wear white and it gets berry or coffee stains.
Black will get baby spew or snot on it. No mum needs their exterior looking as filthy as she feels on the inside. Lycra doesn't absorb much and what gets on it brushes off easily.
5. It's okay to look slightly dishevelled in it
Everyone who has been exercising looks a little scruffy. No one needs to know that you haven't quite made the walk you intended on. Maybe you even stopped intending to go walking.
That's okay because, every morning you do enough exercise getting your little darlings: fed, dressed, to the toilet, to clean their teeth, to stop eating the toothpaste, to stop putting the toothbrush in the toilet, to stop fighting with each other, to put socks on, to put shoes on, to put their shoes back on when they took them off, to get out of your driver's seat and into their car seat, to get belted into said car seat after a 10-minute physical showdown that has you sweating and your Fitbit heart rate monitor reading "108 FAT BURN".
I compete in an endurance event every fricken' morning. This IS my exercise - Lycra and dishevelled appearance (and mental instability) is completely justified.
Just kidding. It's been about 10. Longer? No judgment here. When you're in Lycra, your hair just looks messy because you're so sporty.
7. You don't have any real clothes left
All your nice stuff was for work or going out and things have changed. What you used to wear doesn't fit the same and even if it does, your lifestyle has changed so much that it isn't really suitable.
Plus, you had a clear-out a year ago and just haven't got around to replacing anything.
8. You feel like you look bad in everything else now anyway
Nothing feels or looks quite right anymore and you don't know what you should be wearing or how to wear it.
Your wardrobe full of stuff just DOESN'T MAKE SENSE. Life doen't make sense.
And, your worst fears were confirmed the last time you tried to wear a nice dress after your four-year-old laughed and said "you look funny" before asking you "why is your tummy so big?"