Women's cycle

Understanding your menstrual cycle

The menstrual cycle is a complex hormonal process that typically spans 21 to 35 days, orchestrating changes throughout the body to prepare for potential pregnancy. Understanding the four distinct phases—menstruation, follicular, ovulation, and luteal—empowers you to optimize health, productivity, and physical performance throughout the month. Hormonal fluctuations during the cycle influence not only reproductive function but also energy levels, mood, appetite, exercise capacity, and cognitive abilities ^[1].

The four phases explained

Menstruation (days 1-5)

During menstruation, estrogen and progesterone levels drop, triggering the shedding of the uterine lining. Many women experience fatigue, cramps, and lower energy. This phase often brings mental clarity and introspection, making it ideal for planning and reflection rather than high-intensity activities.

Follicular phase (days 1-13)

The follicular phase overlaps with menstruation initially, then continues as estrogen rises. This hormone stimulates follicle development in the ovaries, boosting energy, confidence, and motivation. Research indicates exercise performance may be slightly reduced during the early follicular phase compared to other phases, with the largest differences observed between early and late follicular phases ^[1]. Many women feel their strongest and most capable during the late follicular phase.

Ovulation (day 14)

Ovulation marks the cycle's peak, with estrogen and testosterone reaching their highest levels. This is when many women experience maximum energy, social confidence, and physical performance. However, research suggests the ovulatory phase may carry an increased risk of certain injuries due to hormonal effects on ligament laxity and neuromuscular control ^[2].

Luteal phase (days 15-28)

After ovulation, progesterone rises while estrogen declines. This phase often brings increased appetite, fluid retention, and mood changes. Some women experience premenstrual symptoms. The luteal phase requires more recovery time and may benefit from increased protein intake and stress management ^[3].

Cycle tracking and health insights

Large-scale studies using mobile tracking data from over 12,000 participants confirm that menstrual cycle characteristics are important indicators of women's health ^[4]. Cycle length and regularity vary significantly by age, with the most regular cycles typically occurring between ages 35-39. Tracking your cycle can help identify irregularities that may signal underlying health conditions.

Practical applications

Rather than viewing the menstrual cycle as an obstacle, many athletes and health professionals advocate for cycle syncing—aligning training, nutrition, and social activities with hormonal changes. The International Society of Sports Nutrition recommends tracking hormonal status against training and recovery metrics to determine individual patterns and needs ^[3]. This personalized approach honors your body's natural rhythms rather than applying one-size-fits-all strategies.