Deep Dive: Chronotype Considerations in Coaching

Reading time: ~5 minutes
Prerequisite: Chapter 2.11 (Sleep Optimization)


The Big Picture

Not everyone is wired for the same sleep schedule. Chronotype—your natural tendency toward morning or evening activity—is largely genetic. Understanding this helps you personalize coaching rather than forcing everyone into the same mold.


What Is Chronotype?

Chronotype reflects your circadian preference:

Chronotype Natural Sleep Time Wake Time Peak Performance
Morning ("Lark") 9-10 PM 5-6 AM Early morning
Intermediate 10:30-11:30 PM 6:30-7:30 AM Mid-morning
Evening ("Owl") 12-2 AM 8-10 AM Late afternoon/evening

Key Point: This is biology, not laziness. Evening types aren't "sleeping in." Their bodies are wired differently.


Why It Matters

Social Jetlag

When chronotype mismatches life demands (work, school), people experience "social jetlag": chronic sleep deprivation and circadian disruption. This associates with:
- Higher obesity rates
- Worse metabolic health
- Increased depression
- Lower performance

Exercise Timing

Research suggests training at chronotype-appropriate times may improve performance and adherence. Morning types do better with morning workouts; evening types with afternoon/evening.

Meal Timing

Late chronotypes eating late may have worse metabolic outcomes, not because eating late is inherently bad, but because it conflicts with their biology (which already tends toward metabolic patterns associated with health risks).


Coaching Applications

1. Assess Chronotype

Simple question: "If you had no obligations, when would you naturally sleep and wake?"

Or use the Morningness-Eveningness Questionnaire (MEQ).

2. Adapt Recommendations

Don't force morning routines on evening types. Instead:

Recommendation Morning Type Evening Type
Exercise time Early morning Late afternoon/evening
Heavy meals Earlier in day May naturally prefer later
Wind-down routine Earlier start (8 PM) Later start (10 PM)
Bright light Upon waking (easy) Need to prioritize morning light

3. Address Social Jetlag

For clients whose chronotype conflicts with obligations:
- Gradual schedule shifts (15 min at a time)
- Strategic light exposure (bright morning light shifts earlier)
- Consistent weekend schedules (don't "catch up" with huge sleep-ins)
- Advocate for flexibility when possible


Limits

Chronotype Is Somewhat Malleable

While largely genetic, chronotype can shift slightly with:
- Age (we become more morning-oriented)
- Light exposure patterns
- Social demands

Don't Use Chronotype as an Excuse

Some clients will use "I'm an evening type" to justify poor sleep habits. True evening chronotype doesn't mean staying up until 2 AM on screens. It means a slightly later natural rhythm.


What This Means for Coaches

  • Personalize timing advice: One sleep schedule doesn't fit all.
  • Morning light helps everyone: Even evening types benefit from bright morning light.
  • Work with biology: Fighting chronotype creates friction; working with it improves adherence.
  • Weekend consistency matters: Huge sleep-ins disrupt circadian rhythm for everyone.

Key Takeaway

Chronotype reflects genuine biological variation in circadian preference. Working with rather than against a client's natural rhythm improves adherence and outcomes, though strategic light exposure can help shift timing when needed.


References

  1. Roenneberg T, et al. Social Jetlag and Obesity. Curr Biol. 2012.
  2. Adan A, et al. Circadian Typology: A Comprehensive Review. Chronobiol Int. 2012.
  3. Facer-Childs E, Brandstaetter R. Circadian phenotype and exercise timing. Br J Sports Med. 2015.
  4. Horne JA, Östberg O. A self-assessment questionnaire (Morningness-Eveningness Questionnaire). Int J Chronobiol. 1976.