The Exercise & Nutrition Scientist: The Truth About Exercising On Your Period! Women Were Right About Menopause! These 4 Supplements Give Women Optimal Health!

There are inherent physiological differences between men and women, rooted in biology from birth, which impact physical characteristics and performance.

Men and women have inherent biological differences from birth that impact physical characteristics and performance.

From birth, men are inherently equipped with a greater number of fast-twitch muscle fibers which contribute to a higher anaerobic capacity and the ability to generate more power as they mature. Conversely, girls are born with more mitochondria, which is indicative of endurance-type fibers that are beneficial for long, slow activities.

Hormonal differences between the sexes lead to significant physiological and body composition variations.

The essential fat percentage in women is higher, sitting around 12%, to support reproductive health, while men have lower body fat percentages, typically in the 4 to 8% range, which is necessary for nerves and survival. Women carry about 20% body composition as a healthy norm, compared to men who are usually around 15%.

Stacy Sims highlights the historically male-centered focus in healthcare and science, exemplified by the use of standard dosages for medications like [restricted term], which do not account for the differences in body composition and metabolism between a 180 pound man and a 120 pound woman.

Women who engage in warrior fasts see a rapid onset of adverse effects, including impaired blood sugar control and increased fat storage, whereas men do not see these effects. Apart from body composition, women are characterized by having smaller hearts and lungs relative to body size, which results in lower oxygen carrying capacity.

Men, favored by higher [restricted term] levels, possess thicker bones that do not degrade as significantly as women's do due to fluctuations in estrogen and progesterone, which impa ...

Stacy Sims highlights the notable differences in how women should approach eating and training at various points in their menstrual cycle, emphasizing the need for a personalized approach based on hormonal fluctuations rather than relying on sports science research primarily based on male data.

The menstrual cycle produces fluctuations in female sex hormones that dramatically impact physiology.

Women experience physiological changes throughout their menstrual cycle that have direct implications on their stress resilience, training intensity, and overall performance which Sims identified during her academic and PhD research.

During the low hormone follicular phase, women have heightened stress resilience and can more effectively tolerate higher training loads.

The follicular phase, lasting from day one to around ovulation on days 12 or 13, is characterized by low hormone levels. Here, Sims mentions that women's immune systems are robust, allowing them to handle higher amounts of carbohydrates and protein without negative effects. Women are more glucose sensitive, enabling better fuel utilization during training. Early research indicated that this phase allows women to push harder in workouts for better adaptations.

In the luteal phase after ovulation, progesterone rises, reducing [restricted term] sensitivity and heat tolerance, necessitating modified training.

After ovulation, during the luteal phase, there's a rise in progesterone, which increases [restricted term] resistance and core body temperature, leading to reduced heat tolerance. Sims suggests changing acclimatization strategies during this phase. She explains that the presence of progesterone leads to conserving glucose for the uterine lining and increased protein needs for tissue development and muscle turnover. Consequently, adapting training by incorporating more carbohydrates around high-intensity workouts and a 12% increase in protein intake post-ovulation is advised.

Monitoring one's menstrual cycle can enable women to leverage their natural hormonal changes.

Through cycle tracking and understanding individual patterns, women can optimize their performance by syncing training and dietary intake with their hormonal changes.

Tracking physical and mental energy levels can guide appropriate training intensity and volume.

Sims urges the tracking of cycle length, bleed pattern, and daily energy levels to identify periods when high-intensity training may not be optimal, thus focusing on recovery or technique. For instance, cognitive and physical strength are generally higher after menstruation starts, with peak strength aro ...

Stacy Sims discusses the significant physiological changes that affect women’s health as they transition through puberty, reproductive years, perimenopause, and postmenopause. Each phase is characterized by different hormonal profiles that require tailored approaches to training and diet.

The hormonal shifts of perimenopause can significantly disrupt a woman's physiology and body composition.

Declining estrogen and progesterone lead to increased [restricted term] resistance, blood lipid abnormalities, and the accumulation of visceral fat.

Sims detailed how changes in estrogen and progesterone ratios, beginning around age 35 until menopause at approximately age 52, can alter body composition and metabolism. Missteps in the liver and mitochondria can result from increased [restricted term] resistance during perimenopause, leading to high blood glucose levels since the body becomes uncertain whether to store or utilize glucose. She further explained that the decrease in estrogen results in a reduction of gut microbiome diversity which impacts serotonin production and the parasympathetic nervous system. A decline in the liver's ability to process fat leads to higher levels of circulating free fatty acids. Reduced anti-inflammatory responses and impaired utilization of these acids lead to the storage of fatty acids as visceral fat, resulting in abdominal adiposity.

Additionally, a greater amount of body fat is linked with a higher incidence of vasomotor symptoms, like hot flashes, while more lean mass can reduce the incidence of [restricted term] resistance.

Perimenopausal women experience sleep disturbances, mood changes, and a decreased ability to maintain or build muscle.

Sims highlighted that common symptoms of perimenopause include sleep disruption and mood changes. The decline in estrogen not only affects mood but also leads to a decreased capability to maintain or build muscle.

Adopting targeted lifestyle interventions can mitigate the symptoms of the menopausal transition.

High-intensity interval training, resistance training, and strategic dietary changes help preserve metabolic health and body composition.

Sims advocates for resistance training to mobilize abdominal fat and increase lean mass. She also stresses the need for a higher protein intake as individuals age, due to increased protein resistance affecting muscle protein synthesis, bone, and nerve regeneration. High-intensity work, consistent resistance training with weights, and exercises like plyometrics are crucial. Focusing on high-quality training with less volume, Sims suggests short, sharp high-intensity cardio or power-based resistance training, combined with cardio exercise two to four times a week ...

Stacy Sims discusses the critical need for recognizing and addressing sex differences in exercise and nutrition strategies. Existing protocols, which are largely based on male data, do not account for the unique biological processes women experience.

Women have different caloric and macronutrient requirements compared to men, particularly around the menstrual cycle

The female hypothalamus is more sensitive to calorie restriction

According to Sims, the female hypothalamus is sensitive to nutrient density. This sensitivity affects the storage of muscle and liver glycogen. In response to calorie restriction, the female hypothalamus can trigger a metabolic downturn and muscle loss. During times of low calorie intake, the body might conserve energy, leading to potential amenorrhea or loss of menstrual cycle. Conversely, adequate calorie intake can ensure better endocrine function, including thyroid activity and menstrual cycle regularity.

Providing a small amount of pre-workout carbohydrate and protein

Sims suggests that for women about to engage in strength training or cardio, consuming around 15 grams of protein, and an additional 30 grams of carbs when it’s cardio, can help maintain blood glucose levels and muscle protein synthesis. This intake supports muscle mitochondria in using free fatty acids rather than storing them. After exercising, consuming 35 grams of protein within 45 minutes can optimize muscle protein synthesis for women in their reproductive years.

Sims explains that the hypothalamus of a woman detects nourishment and fuel during exercise differently from men, and this perception is linked to how carbohydrates consumed are utilized by the body.

Strategic supplementation can address common female health and performance concerns

Iron is critical because it allows blood cells to carry oxygen, and its deficiency can cause severe fatigue. While iron-rich foods are part of the diet, vitamin C enhances its absorption. Additionally, to manage the body’s availability of iron, especially since hepcidin levels increase with inflammation after training, it's recommended to supplement iron before training or at night, away from training times.

Sims also dispels misconceptions about creatine, emphasizing the importance of appropriate dosing. She suggests that women should take three to five grams of creatine daily withou ...