In a thought-provoking episode of The Diary of a CEO, Dr. Stacy Sims, a renowned expert in exercise science and nutrition, shared invaluable insights into how women can tailor their fitness routines and nutrition to align with the natural fluctuations of their menstrual cycle. Here’s a breakdown of the key takeaways, based on Dr. Sims’ extensive research and expertise.

1. Exercise and Nutrition Across the Menstrual Cycle

Dr. Sims emphasizes the importance of adjusting both nutrition and exercise based on where you are in your menstrual cycle. This cyclical approach, known as cycle syncing, can enhance performance, reduce the risk of injury, and improve overall health.

Follicular Phase (Day 1–14): This phase, which starts from the first day of menstruation to ovulation, is characterized by higher energy levels due to rising estrogen. It’s the optimal time for higher-intensity workouts such as strength training and HIIT (High-Intensity Interval Training). Nutrition-wise, protein intake should remain consistent, with 20–25 grams of protein recommended before strength workouts and 15 grams of protein with 30 grams of carbs before cardio.

Luteal Phase (Post-Ovulation to Menstruation): After ovulation, the body shifts into the luteal phase, where progesterone increases, and energy tends to dip. Women may experience symptoms like fatigue, bloating, and increased appetite. During this phase, it’s ideal to switch to moderate-intensity exercises such as yoga, walking, or swimming. Dr. Sims suggests higher carb intake before and after HIIT workouts to fuel the body, along with 35 grams of protein post-exercise. This helps in balancing energy levels and muscle recovery.

2. The Role of Protein and Meal Timing

Dr. Sims underscores the importance of protein throughout the cycle, particularly around workouts. Here’s the breakdown of how to fuel your body at various times:

Before Exercise:

For strength exercises, consume 15 grams of protein before hitting the gym.

For cardio, combine 15 grams of protein with 30 grams of carbohydrates to provide sustained energy.

After Exercise:

It’s crucial to get 35 grams of protein within 45 minutes after exercise to support muscle repair and growth, along with carbs to restore glycogen levels.

3. Supplementation for Women’s Health

Dr. Sims also discusses several key supplements that can support women’s health, particularly for those who are active:

Vitamin D: Dr. Sims recommends Vitamin D3 (functional form) rather than D2 (storage form) for optimal absorption. This helps support bone health, immune function, and overall well-being.

Omega-3 Fatty Acids: Particularly for women in their late 30s, fish oil supplements (rich in Omega-3) can help manage inflammation and support heart and brain health.

Iron: Women, especially those with heavy menstrual periods, may be prone to iron deficiency. Dr. Sims advises keeping ferritin levels between 50–100 and recommends carbonyl glyconate as a highly absorbable form of iron.

4. Adapting Nutrition to the 28-Day Cycle

Dr. Sims delves deeper into how nutrition should change throughout the 28-day menstrual cycle. Here’s the breakdown:

Days 1–6 & 12–13 (Immune Robust Phase): During these days, the body is generally more resilient. This is a great time to push yourself in workouts, particularly in terms of strength and high-intensity training.

Post-Ovulation (Day 14 onwards): Following ovulation, the body’s energy requirements shift. Women should increase their carb intake before and after high-intensity workouts, as carbs help fuel the body during this phase. Protein intake remains important for muscle recovery.

5. Meal Timing and Optimal Eating Windows

Dr. Sims also advises that meal timing can significantly impact metabolic health and recovery. A simple tip she offers is to stop eating by 6 or 7 pm. This helps optimize digestion and improves sleep, both of which are critical for overall recovery and performance.

6. Cold Plunge for Inflammation

Lastly, Dr. Sims highlights the benefits of cold plunges for reducing inflammation, especially for women with conditions like endometriosis. Cold therapy can help in post-workout recovery, reduce soreness, and promote muscle healing by decreasing inflammation.

Final Thoughts

Dr. Sims’ insights offer a science-backed framework for women to optimize their nutrition and exercise routine throughout the month. By adjusting protein intake, workout intensity, and supplementation according to the phases of the menstrual cycle, women can unlock their full fitness potential and improve overall well-being.