Podcast Summary: HBR IdeaCast

Episode: The Case for Designing Work Around Circadian Rhythms

Date: April 7, 2026
Host: Alison Beard & Adi Ignatius
Guest: Stefan Volk, Professor at University of Sydney Business School

Overview

This episode of HBR IdeaCast explores why leaders should pay attention to their own and their team's circadian rhythms—the natural, biological cycles that influence our daily peaks and troughs of energy—and how aligning work schedules accordingly can significantly improve both well-being and performance. The guest, Professor Stefan Volk, shares insights from his research and practical advice for organizations seeking to leverage individual differences in chronotype (morning/evening preferences) for better collaboration, productivity, and health.

Key Discussion Points & Insights

1. What are Circadian Rhythms and Chronotypes?

• Definition and Science

  • Circadian rhythms are internal body clocks synchronized to the planet's 24-hour light-dark cycle ([03:43]).
  • The "circadian clock" is a brain mechanism above the optic nerves, responsible for regulating sleep and wake cycles via hormones like melatonin.
  • The 2017 Nobel Prize in Medicine was awarded to the discoverers of the circadian clock ([03:43]).

• Chronotypes: Morning vs. Evening People

  • Chronotypes describe when individuals feel most alert or sleepy; people are loosely divided into morning types, evening types, and intermediates.
  • Majority of children are morning types; teenagers move toward eveningness; adults become more distributed ([03:43]).

  "An extreme morning person and an extreme evening person could share a bed, would never see each other because they have such opposed rhythms." — Stefan Volk [04:50]

2. Effects on Productivity and Emotional States

• During Peak vs. Trough

  • At circadian peak: greater alertness, cognitive function, self-control ([05:53]).
  • At circadian trough: reduced self-control, more moodiness, impulsivity; higher potential for conflict and poor decisions, especially relevant for leaders ([05:53]).

  "When we are at our circadian trough...we are more moody, we are more impulsive, and as a result, we can be more impatient, more irritable, even more aggressive." — Stefan Volk [06:23]

3. Why Leaders Should Care

• Assumptions & Biases

  • Leaders often mistake their own rhythm for the norm (“morning bias”), failing to recognize team diversity ([07:04]).
  • Underappreciation of differences leads to missed opportunities for leveraging strengths, scheduling errors, and even unfair performance evaluations ([07:04], [18:39]).

  "People that are more morning types ... assume that others are also more productive in the morning. And that is obviously not the case." — Stefan Volk [07:16]

• Impact on Teams

  • Scheduling sensitive conversations or collaboration during individuals' troughs increases risk for conflict and miscommunication ([09:16]).

4. Can People Shift Their Rhythms?

• Biological Constraints

  • The circadian system is not easily trainable or adaptable. It changes extremely slowly; chronotype in adulthood shifts only about 7 minutes per decade ([10:26]).
  • Attempts to "become" a morning person usually lead to sleep deprivation and related negative consequences ([10:26]).

  "People that try to become morning people simply cut down on sleep. And when you cut down on sleep, it has a whole range of ... negative consequences in relation to your performance, in relation to your health, and in relation to your moods and emotions." — Stefan Volk [11:45]

5. Distributed Teams, Flexibility, and Hybrid Work

• Flexplace vs. Flextime
  • The pandemic advanced flexible workplaces but not necessarily flexible hours; most teams still stick to traditional core hours ([12:31]).
  • The guest suggests hybrid schedules with a core period for collaboration (e.g., 10-3) and flexible hours before/after for individual work ([12:31]).

6. Discovering Your Chronotype

• Self-Assessment
  • Easiest method: Note when you naturally wake up on weekends without an alarm ([13:36]).
  • Chronobiology offers validated questionnaires for teams and individuals, useful as a starting point for conversations and planning ([13:36]).

7. Practical Approaches for Leaders & Teams

Optimizing Individual Work ([16:39])

• Tackle the most challenging or unpleasant tasks during your peak.
• Avoid spending peak hours on low-value, routine tasks like email ("morning inbox problem" [17:01]).

Adjusting Team/Organizational Practice ([18:39], [19:54])

• Culture is Set from the Top: Leader's rhythm often drives the schedule, sometimes unfairly benefiting those with matching types.

• Awareness and conversations about rhythms foster fairness and adjustments even if wholesale change isn’t possible.

• Schedule key meetings/brainstorming sessions during late-morning, when most people’s alertness overlaps ([22:25]).

  "The beauty of the team is that you can really leverage these differences and coordinate them in a very productive way as much as possible." — Stefan Volk [21:32]

• For cross-type work, find a middle-ground time (e.g., noon for a morning-leader and evening team member).

When Team Members Must Work Outside Their Peak ([23:39])

• Recognize that work outside peak will be slower, harder, and more draining; rotate assignments when possible, build in recovery.

• Double-check work and offer more support during troughs.

  "If you do this constantly, people are much quicker burning out or developing other health problems. ... We have to allow for recovery." — Stefan Volk [23:54]

Concrete Organizational Examples ([25:12])

• Trivago: CEO blocks off mornings for solo, challenging work—no meetings.
• Citigroup: Teams scheduled based on cross-border time zone compatibility, boosting performance and happiness.
• Sectors like aviation/transportation have leveraged shift alignment for decades; benefit extends to knowledge work.

Notable Quotes & Memorable Moments

• "All the important things happen in the morning, right? Like it starts in school with exams... important meetings all usually happen ... during the first half of the day, when the morning people are having an advantage while evening people are at a disadvantage." — Stefan Volk [14:12]

• "Trying to become a morning person simply cuts down on sleep ... that has a whole range of negative consequences in relation to your performance, your health, and your moods and emotions." — Stefan Volk [11:45]

• "At the fringes of the day, in early morning, in the late evening, you're more likely to lose a substantial fraction of your team." — Stefan Volk [22:28]

Timestamps for Key Segments

• [03:43] — Circadian rhythms explained; why they matter for work
• [05:53] — How peaks and troughs affect performance and mood
• [07:04] — Leaders’ own bias and the importance of team rhythm awareness
• [10:26] — Why you can’t “train” yourself to shift chronotypes
• [12:31] — Hybrid work: Flexplace vs. actual flextime
• [13:36] — How to discover your own and your team’s chronotype
• [16:39] — Applying insights: How to structure personal and team work
• [22:25] — Scheduling team collaboration for maximum effectiveness
• [25:12] — Real-world organizational examples

Actionable Takeaways for Leaders

• Start team conversations about chronotypes; use free questionnaires for discovery.
• Schedule challenging and important work for individual/team peak times.
• Avoid meetings during early afternoons—energy dips are biological, not just “lunch-related.”
• Build organizational flexibility wherever possible: consider core overlapping hours and flexible extension time.
• Recognize bias (especially if you’re a leader), and avoid penalizing diverse work rhythms.
• When off-peak work is necessary, rotate assignments and prioritize recovery.

Closing Thoughts

This episode provides a science-backed argument for rethinking traditional work schedules and being intentional about leveraging natural differences in team rhythms. When leaders and organizations design for, rather than against, circadian diversity, they can unlock both better performance and improved employee well-being.

Guest: Stefan Volk, University of Sydney Business School & author of Tapping into your Team’s Circadian Rhythms ([27:09])