My hump, my hump, my lovely lady lumps…
Um, ya – thanks Fergie…
Nevertheless – if you are a lady, you have some special anatomy! So I thought my first blog post should highlight some of what physically makes a woman’s body different from a man’s. Many of these differences are the very things that will serve as the basis for future posts!
The fancy name for the variations between a woman’s and a man’s body is known sexual dimorphism. Well, specifically sexual dimorphism refers to the phenotype differences between the sexes, or the differences in the characteristics we can “see”.
Let’s start with the obvious: external genitalia. Men have a penis and testicles and women have a vagina! Vagina, vagina, vagina! Women also have more breast tissue (including glands and milk ducts). On the inside our reproductive organs are also different; women have ovaries and a uterus, while men have testes. There are also some other important bits we will talk more about later. Great – you all remember what you learned in your grade 6 sex ed. class. Oh right – and men tend to have more body hair!
Now fast forward to high school biology. You also know that girls tend to hit puberty about 2 years before boys, but that the average male tends to be taller and heavier than the average female. Men also tend to be stronger: some studies estimate that women only have between 50-60% of the upper body strength of men, but closer to 70% of their lower body strength. Olympic weightlifting records are also substantially different even in similar weight categories – for the “snatch” at a weight of 62 or 63kg (males and females respectively) the record lift is 153 kg for men and 115kg for women.
Our skeletons are also a little different, most notably in the pelvis – a woman’s pelvis tends to be shorter but wider (hello childbirth!), and since the pelvic ring is wider, the acetabula (the “socket” part of the hip joint) are wider apart too. Women also tend to have a higher percentage of body fat (~20-25%) than our male counterparts (10-15%) – don’t groan, we’re supposed to! Where we store our fat is also a little different; think breasts, upper arms, bum, and thighs for women but bellies for men!
In addition to fat storage, there are also differences in how women mobilize and metabolize fat. I’m not going to get into the details, but you can bet estrogen likely plays a role… which brings me to hormones!
Female hormones vary from a male’s in kind and quantity – but this is the beauty in our design. Physiologically we are designed to carry out some very special functions: menstruation, pregnancy and lactation. Luteinizing hormone, follicle-stimulating hormone, estrogen, progesterone, prolactin, relaxin… these are all players in our game. And it’s also my opinion that these hormones actually play a far greater role than in just our reproductive health; so, even if you haven’t carried a baby and don’t plan to, these chemical messengers matter to you. I think our endocrine system isn’t that well understood and I have a hunch the system is probably even more complex than we might imagine… I think these hormones also affect the tissues our bodies are made up of (ex. muscle, connective tissue, etc.).
Now there’s a bunch of differences just touched on here – it’s the tip of the iceberg. And as you were reading along you might have felt a prickle when reminded about the differences in muscle mass, strength and body fat especially. But please, please, please don’t look at these numbers and consider yourself part of the “lesser” sex!
I personally refuse to believe there are flaws in our human body designs. Let’s find more ways to celebrate what makes up a lady!