Menstrual Cycle & Trail Training: How to Adapt Your Workouts?

Menstrual cycle and trail running training

Menstrual Cycle & Training: Listen, Understand, Adjust

The menstrual cycle and training remain a topic too rarely addressed in trail running. Between marketing hype, oversimplification, and on-the-ground reality, one question often arises: should you adapt your training to your cycle?

The answer requires nuance.

The Menstrual Cycle Influences… But Not As We Imagine

On paper, hormones vary:

  • Estrogens → potentially favorable effects (energy, vascular)
  • Progesterone → increased body temperature, ventilatory cost

Logically, one might expect significant variations in performance.

In reality, science shows something else: the effects exist… but remain minor and highly variable from one athlete to another.

Impact of menstrual cycle on trail training

No "Magic" Phase

Major scientific analyses show:

  • No clearly optimal phase
  • No systematically unfavorable phase
  • Very small differences on average

In other words: your body doesn't follow a universal plan.

Two athletes with the same cycle can experience entirely different things.

The Real Lever: Perceived Exertion

Where the cycle truly plays a role:

  • Fatigue
  • Pain
  • Discomfort
  • Motivation
  • Ability to handle intensity

It's not so much physiological performance that changes, but the ability to produce effort. This is a key distinction.

Adapting trail training to the menstrual cycle

What Science Says

Scientific studies on the menstrual cycle and athletic performance

The landmark meta-analysis by Kirsty McNulty (2020) compiles 78 studies and concludes:

  • Impact of the cycle on performance → trivial to small
  • No clearly optimal phase
  • High individual variability

More recent work confirms:

  • No clear effect on strength or endurance
  • Similar training adaptations between phases

However, a study by Guro Solli (2020) shows that:

  • Many athletes feel variations
  • Especially during menstruation
  • Linked to symptoms (pain, fatigue)

Scientific conclusion: the menstrual cycle influences perceived exertion more than raw performance.

Practical application of adapting training to the menstrual cycle

Practical Application: How to Adapt Your Training

What works in the field:

  • ✔️ Observe your cycle
  • ✔️ Note your sensations
  • ✔️ Adapt day-to-day
  • ✔️ Use RPE (Rate of Perceived Exertion) as a guide
  • ✔️ Adjust without rigidity

Concrete Examples of Adaptation

  • "Good" day: session maintained
  • "Average" day: intensity adjusted
  • "Tough" day: session lightened or moved

The goal: continuity + listening + adaptation

What to Avoid

  • ❌ Rigidly planning according to phases
  • ❌ Believing in a "perfect phase"
  • ❌ Ignoring symptoms
  • ❌ Pushing against your body's signals

Key Takeaways

  • ✔️ The menstrual cycle influences the body
  • ✔️ Its impact on performance remains small
  • ✔️ Responses are individual
  • ✔️ Perceived exertion becomes a key indicator
  • ✔️ Smart adaptation beats universal rules

— Antoine, Baptiste, and Etienne from TRL