Dr. Stacy Sims (Part 1): Understanding Hormones, Supplements & Exercise

**Sarah Grynberg** (0:00)
Welcome to my three-part series with Dr. Stacy Sims. Stacy is an internationally renowned exercise physiologist and nutrition scientist, recognized globally for her groundbreaking work on female physiology, hormones, and performances. She has worked with elite athletes, written bestsellers like Raw and Next Level, and is redefining how women train, recover, and fuel their bodies. This is episode one, where we'll dive into hormones, supplements, and exercise, exploring what really happens in the female body, how our needs shift across stages, and the practical strategies that can help us work with our biology instead of against it. Stay tuned because in episode two, we'll go deeper into diet, alcohol, and injury prevention and management.

**Stacy Sims** (0:56)
If you are like, I need to supplement, you need to talk to your doctor and find out what's the best kind of supplement to use, and do it for a couple of menstrual cycles, just the first day of your bleed, every other day for about 10 to 12 days, and see how that makes you feel.

**Sarah Grynberg** (1:19)
I'm Sarah Grynberg, and this is A Life of Greatness.
Through my years of studying and researching the connection between human behavior, personal growth and transformation, I have discovered the keys to unlocking greatness within others. In this podcast, I share stories and experiences from my own teachings, along with conversations with inspiring guests to help you learn the simple tips, habits, practices and strategies to cultivate an extraordinary existence. My hope is that this episode gives you a new sense of power over your body and the knowledge to make choices that will truly serve you long term. Stacy, welcome back to A Life of Greatness. It's so good to have you here again.

**Stacy Sims** (2:08)
Thanks for having me. I'm looking forward to chatting.

**Sarah Grynberg** (2:11)
We are going to deep dive into a lot more topics than we did last time, because there's obviously so much to talk about with you. I wanted to start by asking you, what made you an expert on hormones and knowing the right supplements to take?

**Stacy Sims** (2:28)
That's a good question. I think it was more self-discovery, having the opportunity to be around the research experts and finding out what some of the holes in the research was, then being able to go answer them. Then I'm always the person from when I was a little kid that asked why. Why does it work this way? Why does it work for one person and not the other? Digging down into the molecular aspects of nutrition really, and trying to figure out how a hormone will make a cell respond to certain things or not others, and how supplements can help boost that and augment that signal or not.
It was just really the incredible desire to know why on the basic level, how things are happening and then bringing it up to the whole body. It's just been self-discovery and inquisition through my entire life that is now come out. Now people are like, hey, wait, you're the expert we want to talk to. I'm like, okay, I'll tell you why.

**Sarah Grynberg** (3:30)
We're hearing so much about hormones these days. I feel like it's really everywhere. Can you talk to us about firstly what hormones are and why they fluctuate and what different stages of life you would find and we'll obviously hone in on women. What different stages you would find that you would have fluctuation in hormones?

**Stacy Sims** (3:56)
Yeah, so hormones are really messenger compounds that will tell a cell to do a certain thing or not to do a certain thing.
When we talk about hormones, most of us think about sex hormones like testosterone, estrogen, progesterone, but we also have things like follicle stimulating hormone for women, which is what helps the egg develop. We have luteinizing hormone, which is another really important hormone that drives our progesterone pulse, our FSH pulse. For men, it helps drive testosterone, it helps control our other hormones, our appetite hormones, which are in response to are we hungry or not. So hormones are these little messenger signals that go all around the body. When we're talking specifically about sex hormones, which is how this whole conversation within women's health, and in some regards, men's health has come around too, we see there is an incredible shift around puberty. So for girls, we start to see a shift around age eight, nine, and then boys a little bit later. And this is when we have a divergence where your body really has gotten the signal to start producing more testosterone in boys or starting to prepare the body to be able to drop an egg for fertilization and getting into our reproductive years in girls. So we see that every system of the body has some kind of signal receptor to these hormones. So we see in boys, it's the acceleration of lean mass and bone development. We see it also helps change the way that the brain is. So we see differences in in aggression and the way that they respond to their environment. In girls, we're seeing an increase in body fat, a change in biomechanics where center of gravity drops. The hips widen to allow for a uterus that's growing, the shoulder girdle widens to allow for that balance. When our hips widen, we see changes in mood and the development of different brain structures. So they're very important in just total development. And then from a day to day perspective, for women, we have different pulses. So if we see a picture of a menstrual cycle in a textbook or a graph, it represents just a general trend, but it doesn't actually represent what's happening in the body. We don't have a linear progression. We don't have a standard line of a hormone. We have pulses throughout the day. So cortisol is a hormone and we know that it comes up and it goes down and it is in response to different stresses throughout the day. So it's a necessary hormone. We see that estrogen, progesterone and testosterone, as well as luteinizing hormone, all have a similar pulse throughout the day. So it's not this linear thing where we go and get tested and go, oh, today your XYZ hormone is this level. It's at this time of day, this is what it is. So we compare time of day because of these different pulses. We see a serious significant shift in the way that this pulse responds when we start to hit perimenopause. So the body is not producing as much of a robust amount of estrogen. We can't really dictate how much follicle stimulating hormone is coming because it depends on how much egg is responding to that FSH. So we're seeing these different pulses and different strengths of the pulse. And so that's why we start having all these perturbations in perimenopause as our ovaries are starting to wind down, which is why we say it's the reverse of puberty. So when we're talking about hormone and hormone health and about, quote, balancing hormone, I think there's this misstep that people think that if we have a steady level of estrogen and a steady level progesterone and a steady level of testosterone, we're going to be OK. But in fact, we have to look at how our circadian rhythm plays into different pulses, how our stress affects those pulses, how our age, where we are, what kind of training we're doing. All of these things affect our daily impact on how our hormones are responding.