Podcast 132: Dr. Stacy Sims on Nutritional Differences Between Men & Women

Dr. Stacy Sims joins the WHOOP Podcast to discuss the impact food has on performance and why women should think about nutrition differently than men do.

When it comes to performing at your best, we all know that exercise and nutrition are essential. But, few studies, coaches and products are taking into account one of the most significant factors at play: Your biological sex. Here at WHOOP, we’ve been looking at the role hormones have in everything from sleep, to recovery, to even digestion. On this week’s podcast, we talk to Dr. Stacy Sims – a leading researcher and author who specializes in female physiology – about the role food has in performance, how women should think about nutrition differently than men, and how womens’ hormonal cycles affect their training. Dr. Sims sits down with WHOOP VP of Performance Kristen Holmes and WHOOP VP of Data Science and Research Emily Capodilupo for this discussion. Enjoy!  

Dr. Stacy Sims Podcast Quotes and Highlights

4:32 - Women Are Not Small Men. Check out Stacy’s TedX Talk. 6:27 - Data Differences. “If you’re a female athlete or you’re a woman who exercises for a purpose and you’re working really hard and not seeing results, it’s probably because most of the stuff we know and do, if not all of the stuff we know and do, is based on male data.” 7:25 - Nutrition. “Regardless of what diet belief you might have, it comes down to fueling for the stress. It doesn't matter if you’re a strength athlete, an endurance athlete, team sport [athlete], you need to fuel for the training stress. We don’t train and get fit during the training. What happens during training is we’re breaking everything down and your body is under an incredible load of stress. If you’re also adding in a non-fueling or poor-fueling stress on top of that, it’s above and beyond the stress needed for exercise adaptation.” 9:17 - The Underfueled Female Athlete. “One of the biggest things with recreational female athletes is they’re underfueling and they’re in a low energy state. The backlash of that is they don’t lose weight, they don’t build lean mass, they have poor sleep. Most of the time they think ‘I’m not training hard enough and I’m eating too much.’ It becomes a vicious cycle.” 10:41 - Signs of Underfueling. Stacy says extreme “to the core” fatigue, both physical and mental, and poor sleep are signs that you might not be fueling your body properly. Pro Cyclist Tayler Wiles on Fatigue's Effect on Her Body 12:20 - Intermittent Fasting and Meal Timing. Stacy explains why she’s not a believer in intermittent fasting. “We’re so unconditioned to meal timing. Whereas if you were to eat a proper dinner and then stop and then not eat again until breakfast, that’s a good fast,” Stacy says. “A lot of people can hold [intermittent fasting] for about 3 months, and they’re off the deep end. … 3 months is about as far as I've seen women can hold an intermittent fast without having repercussions.” Stacy also explains the psychological differences between men and women and why women might not respond as well to fasting. “For women and men, it’s a different story,” Stacy says. 16:54 - Dieting as a Couple. Emily and Stacy discuss how couples often take on the same diet together, but get different results. “You need to eat differently,” Stacy says of men and women. 18:39 - Iron Deficiencies. Stacy explains why women over the age of 35 can start to deal with iron deficiency and what they can do about it. 20:33 - Sugar. “There’s a time and place for it,” Stacy says. “A little bit is fine. … It’s not as bad as people think, but in the States it is because I feel like everything has sugar added and that’s where you need to be careful.” Stacy points out that maple syrup and honey are excellent sources of sugar. 25:12 - Sports Drinks, Gels & Bars. “Marketing is stronger than science in the sports nutrition world, especially when you’re talking about the myth of needing salt tablets and electrolyte replacement. Even in Ironman, if you’re eating properly and you’re fueling properly, you don’t need to replace stuff. You’re not going to sweat out all the sodium in your body. Your body has plenty of sodium stores.” 28:11 - Gaining a Better Understanding of Female Performance. Stacy notes that few performance studies before 2004 even included women. “The vast majority of research that our training is based on actually doesn’t really apply to [women] or we don’t understand how it maybe needs to be modified to apply,” Emily adds. Connect with Stacy: Drstacysims.com, Instagram, LinkedIn