Stacy Sims, PhD: The ‘Everything’ Guide for Female Athletes — How to Navigate Your Menstrual Cycle, the Menopause Years, Cortisol and Stress, Nutrition Needs, and More

September 7, 2016


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Stacy Sims, PhD, joins the show for a second time to talk all about women, and how female athletes can maximize their potential by understanding their bodies, and how women function differently than men. Stacy recently released a new book co-authored with Selene Yeager titled ROAR: How To Match Your Food And Fitness To Your Female Physiology For Optimum Performance, Great Health, And A Strong, Lean Body For Life (available on kindle or paperback). Listen to our previous with with Stacy all about hydration.

On this episode:

Men vs. women

  • The basic differences
  • Women: type 1 fibers more efficient for burning fat and sparing glucose. But in recovery burn more carbs and metabolism back to baseline faster than men’s.
  • More prone to catabolism—hormones

Menstrual Cycle & Support

  • What happens during a cycle, the phases, hormone fluctuations, ovulation, etc, and how this ties in with performance, training, racing.
  • Estrogen and progesterone
  • 1st phase – your prime time! Why you’re most like a man on Day 1 and that first week of cycle, stronger and it feels easier. Women also access carbs “more easily” during this time
  • 2nd phase – high-hormone phase, PMS, and generally not able to perform as well. Reduced reaction time, coordination off, etc. Women burn more calories during this time (5-10% increase in metabolism).
  • Fat vs carb burning in 1st vs 2nd phase
  • Other issues during the 2nd phase/luteal phase:
    • Loss of plasma volume up to 8%
    • Higher progesterone which has a catabolic effects (more protein and BCAAs especially leucine)
      • Mitigates CNS fatigue
    • Metabolism changes
    • Not as effective at cooling (run hotter), so add more ice and cold drinks
    • Bloating, cramping, GI issues, mood, etc.
    • Most at risk for hyponatremia during luteal phase, no more than 27 oz/hr
    • Is there any reason to believe that being LCHF during the high-hormone phase to mitigate PMS issues?
    • Value of leucine
    • Value of fish-oil during the luteal phase to mitigate PMS and menstruation symptoms
  • Why and how things “get better” on Day 1—although, the day you feel great again will vary for women due to cramping and other issues associated with the onset of menstruation
  • Cramping is not your hormones
  • Estrogen spares carbs
  • To get into fat-burning you actually need a bit more carb
  • Low-hormone (first phase) you can stick to limited fueling with your workouts
  • Risks of oral contraceptives 25
  • Carbs for women: 130-140 grams a day MINIMUM
    • Ketosis only really works for men
    • Ancestral reasoning

Amenorrhea, missing periods and stress

  • Female athlete triad vs. RED-S—not just the three factors, what is RED-S?
  • Missing periods even if BF is reasonable, up to 30%.
  • What are root causes:
    • Inadequate nutrition and energy availability and/or hypo-caloric diets that don’t meet needs as athlete
    • High-stress and high cortisol, stress can be from many things not just exercise
  • The science (hormonal response) of what happens with too low carb and/or hypocaloric
  • Risks of intermittent fasting (IF) for women: IF can lead to high cortisol > adrenal fatigue
  • Cautioning against fasted workouts if you are a woman
    • Fasted training directly increases cortisol, and this can backfire leading to insulin resistance
    • Fuel before esepcially with amino acids
    • Fuel can be a small snack if not hungry like 100-150 calories
  • Study mention by Tawnee: Light IF like 12-14 hour overnight actually improved women in the luteal phase. But that longer fasts like up to 24-48 hour or alternating fasting led to negative outcomes and actually decreased glucose tolerance
  • However: lowering carb intake to avoid typical Western diets isn’t a bad thing, meanwhile increase fats/proteins to avoid too low calories; just avoid too low carb

Peri- and post-menopausal athletes

  • The top things we need to know about our later years
    • Estrogen drops off
    • Changes in diet and training needs
      • Two easy days after every hard day
    • Train the high-end to maintain power output
    • Thirst sensation even more dampened
    • More intolerant to carbs and fructose
  • Risk of eating fructose, sugar and high GI foods/drinks
    • Not as easy to store excess energy from fructose as fat so instead remain as FFAs in blood—metabolic havoc and IR
    • Harder to convert fructose to glucose
  • More sensitive to carbs and carb intolerant, due to less estrogen and DHEA
  • Also not as good at fat burning nor retaining/building muscle
  • Body composition changes in the post-menopausal woman
  • Hormones and sleep issues—60% of Post women complain of insomnia issues, what’s the deal?
  • Melatonin: progesterone and other hormone’s effect on melatonin—and this can go for all women
  • Sleep supplements: Tart cherry juice (get the liquid form)

Weight & Nutrition

  • On carb quality and Tawnee’s one “bone to pick” with Stacy on carb recommendations that include grains, gluten, wheat…. are these the best choices for women if GI issues are a potential or real issue?
  • Sports nutrition guidelines
  • When to take nutrition and/or focusing on the right pre- and post-fueling vs. when can we go without specific fueling?
  • Eating for your physiology: Are you an ectomorph, mesomorph, endomorph or combo? And how to eat for your body type

Comments (11)

  • kt says:

    I’d love to know what brand of tart cherry juice Stacy recommends? There are so many out there now ranging in price from $3/bottle all the way up to $40/bottle! What should I be looking for when choosing a tart cherry juice?

  • Kathy Dreiblatt says:

    Wow, Tawnee! As a female athlete turning 53 TOMORROW, this is ABSOLUTELY BRILLIANT!!! And just what I needed to hear! This is one of your most groundbreaking episodes, ever! Thank you!

  • Kathy Dreiblatt says:

    I am so confused, Tawnee. Didn’t you used to always tout lo-carb “fat burning” diet?????? Wasn’t that a huge issue you talked about on the podcast?

    • admin says:

      Hi Kathy, Yes we do want people to get off carb and sugar addictions and overly relying on carbs in an unhealthy manner. But take a look at my reply to Jennifer also in the comments section, and hopefully I can provide more insight to avoid confusion!

  • […] was listening to Stacy Sims discussion last night with Endurance Planet about the most talked about women’s topic, mentrual cycle and menopause – how it […]

  • Jennifer says:

    I am a bit confused as well. Seemed like high fat low carb is not the way for endurance female athletes? I just switched over to high fat low carb and have been feeling better than ever but am confused about this new info now. I thought the goal of a fat adapted athlete was not to feel hungry all the time. I can finally go hours without eating during a competition but maybe I’m doing more harm than good? Would be interesting to have Stacy Simms and Phil Maffertone on the podcast together! Love all this info and the chance to hear from all of these amazing researchers. A highlight of my week!

    • admin says:

      Hi Jennifer, I totally understand where you are coming from – it’s not easy, and can seem confusing, but there is valid reasoning here and a way to clear up the confusion 🙂 You are not wrong by adjusting your carbs to be more fat adapted and not “hangry” all the time, but chronically too low carb for women can be problematic. I’ll be doing a webinar on this over at on Sept. 29 and talking more specifics on carb needs.

  • Michael says:

    Tawnee – you and stacy mentioned a fermented buckwheat recipe … where can i find it?

  • Jo says:

    Hi, After hearing this podcast, I bought Roar. It recommends as a Mesomorph, ore-training, I should have almond milk with 5 BCAA’s. I’m not sure what form the BCAA’s are exactly and what the measurement of 5 indicates. Any ideas?

    In the podcast, it is also discussed that you can eat for the body type you want to be rather than the one you are. I put on muscle very easily and want to slim down the bulky muscle. Which body type should I then be eating for.. one with less protein..?

  • […] ourselves on our unique physiology and if you want to do so, I highly recommend listening to THIS podcast and reading THIS book.  Dr. Stacy Sims puts it best when describing female […]

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