Protein Matters: How Much Protein Do Women Really Need? How Your Menstrual Cycle Affects Muscle Growth and Performance?

Protein is often called the building block of life, and for good reason. It plays a crucial role in muscle repair, immune function, and overall health. But how much protein do you really need, and why is it so important?

Why Protein is Essential

Protein is involved in almost every function of your body, including:

• Muscle Growth & Repair – Helps rebuild muscle tissues after exercise- some amino acids like leucine, are especially important because they help trigger muscle growth.

• Metabolism & Weight Management – Increases satiety and boosts calorie burning.

• Immune Function – Supports the production of antibodies and enzymes.

• Hormonal Balance – Essential for producing hormones like insulin and growth factors.

  
  

The general recommendation for protein intake is 0.8 g per kg of body weight per day, but research suggests that women, especially active ones, need more—around 1.6 g/kg/day or higher, depending on activity level and goals.

However, protein needs aren’t the same every day.

A woman’s menstrual cycle affects how her body uses protein, meaning her intake and workout routine should adjust throughout the month for optimal performance and recovery.

How Protein Needs Change During the Menstrual Cycle

1. Follicular Phase (Days 1–14, starts with menstruation)

   • What happens? Estrogen levels rise, energy levels increase, and the body becomes more efficient at using carbs for fuel.

   • Protein needs: Moderate (1.4–1.6 g/kg/day). The body can build and repair muscle more easily during this phase.

   • Best workouts: Strength training, high-intensity workouts (HIIT), endurance activities (running, cycling). Energy levels are higher, so this is the best time for intense training.

2. Ovulation (Around Day 14)

   • What happens? Estrogen peaks, leading to high energy and strength, but also an increased risk of injury due to ligament looseness.

   • Protein needs: Similar to the follicular phase (1.5–1.7 g/kg/day). Focus on recovery.

   • Best workouts: Moderate strength training, low-impact cardio, mobility exercises. Avoid excessive high-impact activities to reduce injury risk.

3. Luteal Phase (Days 15–28, before menstruation)

   • What happens? Progesterone increases, protein breakdown rises, and the body relies more on fat for energy. Many women experience fatigue, cravings, and bloating.

   • Protein needs: Higher (1.6–2.0 g/kg/day) due to increased protein oxidation and muscle breakdown. More protein helps maintain muscle and prevent fatigue.

   • Best workouts: Moderate-intensity strength training, yoga, pilates, walking. If energy is low, focus on mobility and recovery rather than intense workouts.

Why Adjusting Protein & Workouts Matters

• Eating more protein during the luteal phase can help combat muscle breakdown and cravings.

• Strength training is most effective during the follicular phase, while lighter workouts may be better in the luteal phase when energy dips.

• Proper protein intake ensures muscle maintenance, better recovery, and hormonal balance throughout the cycle.

By aligning protein intake and workouts with the menstrual cycle, women can optimise energy, performance, and muscle health while reducing fatigue and injury risk.

References

1. Beals, K. A., & Flanagan, S. D. (2020). The impact of menstrual cycle phase on exercise metabolism. European Journal of Applied Physiology. Retrieved from PubMed

2. Ivarsson, A., et al. (2020). Protein needs of premenopausal female athletes: A systematic literature review. Nutrients. Retrieved from MDPI

3. McNulty, K. L., et al. (2021). The effects of menstrual cycle phase on athletic performance: A systematic review. International Journal of Environmental Research and Public Health. Retrieved from PubMed Central

4. Julian, R., et al. (2023). Influence of menstrual cycle phases on exercise metabolism. Frontiers in Sports and Active Living. Retrieved from Frontiers