I was listening to a recent episode of HBR Ideacast from Harvard Business Review on designing work around circadian rhythms… and it had me thinking about something I had not paid attention to unless talking to shift workers.
Not because the idea was completely new but because it made me realise how much of our working world is built on a quiet assumption:
Everyone should perform well at the same time of day.
And when you say it out loud like that, it sounds a bit ridiculous.
The episode of the podcast explains something we all kind of know but rarely act on:
We each have a built-in biological clock, our circadian rhythm that determines when we feel sharp, sluggish, creative, or… completely useless in a meeting.
Some of us are:
- Morning “larks”
- Evening “owls”
- Or somewhere in between
And here’s the kicker: these patterns aren’t just preferences they’re biologically ingrained and relatively stable over time.
So when workplaces force everyone into the same 9–5 rhythm, we’re not creating alignment… We’re creating friction.
It’s Not Just Energy, It’s Decision-Making, Mood, and Performance
One part of the episode really stuck with me: performance doesn’t just dip slightly outside your peak it changes qualitatively.
At your peak:
- You’re sharper
- More focused
- Better at solving problems
At your low point:
- You’re slower
- More impulsive
- More irritable (we’ve all been there…)
Now think about that in a workplace context.
How many:
- Difficult conversations
- Performance reviews
- Strategic decisions
…are happening when someone is at their worst time of day?
That’s not a people problem.
That’s a design problem.
Light, Environment, and the Hidden Factor We Ignore
One of the more interesting rabbit holes I went down after the podcast was how light exposure plays into all of this. I’ve known about trying to get sunlight in during the day, that’s mainly because I live in Ireland and even when there its raining I try to go out for a short 20min walk at lunchtime even in December.
Our circadian rhythms are heavily influenced by light, especially natural light. It’s what signals our body when to wake, focus, and wind down.
Research shows that exposure to natural light in workplaces is linked to:
- Better sleep
- Improved mood
- Increased workplace performance
There’s even a growing conversation around circadian lighting, (yes its a marketing description also) designing lighting systems that mimic natural daylight patterns to support energy and alertness throughout the day.
So this isn’t just about when we work. It’s also about where and how we work.
What This Means for HR and Leaders (Without Overhauling Everything)
Here’s the good news, you don’t need to redesign your entire organisation/team tomorrow.
What stood out across the research is that small, intentional changes can unlock real benefits.
A few ideas that feel both practical and low-risk:
1. Stop Assuming Your Rhythm Is the “Right” One
Leaders often unintentionally impose their own schedule preferences on teams.
If you’re a morning person, it’s easy to believe mornings = productivity.
That’s not true for everyone.
2. Design for Overlap, Not Uniformity
Create core collaboration windows (e.g. 10am–3pm), and allow flexibility outside of that.
This gives you:
- Enough overlap for teamwork
- Enough flexibility for individual peak performance
3. Match Tasks to Energy (Not Just Time Slots)
- Peak energy → deep work, strategy, problem-solving
- Mid energy → meetings, collaboration
- Low energy → admin, routine tasks
And yet… most calendars are the exact opposite.
The Experiment I’m Genuinely Keen to Try
The “Alternating Meeting” Experiment
- Week 1: Team meeting at 9am
- Week 2: Same meeting at 3pm
- Repeat for a month
Then observe:
- Who speaks more?
- When do better ideas emerge?
- When does the meeting feel… less painful?
You don’t need a big transformation to start learning. You just need to test it.
A Few More Practical Ideas I’ve Picked Up
- “No-meeting mornings” once or twice a week
- Let people self-identify their peak hours
- Rotate timing for recurring meetings
- Be mindful of light exposure and workspace design
- Accept that not all hours are equal
Even small alignment improvements can create a real “circadian business advantage” better output without longer hours.
Try This (A Simple 2-Week Experiment)
Step 1: Ask your team:
“When during the day do you feel most focused?”
Step 2: Change just one thing:
- Move a meeting
- Add a no-meeting block
- Let people shift start times
Step 3: Watch:
- Engagement
- Energy
- Output quality
That’s your data.
Final Thought
We’ve spent decades optimising work around time.
But the real opportunity might be optimising around energy.
Because when people are working with their biology instead of against it:
- Work gets better
- People feel better
- Leaders make better decisions
And honestly… that feels like a pretty good place to start.
References & Further Reading
- Harvard Business Review (2026). Tapping Into Your Team’s Circadian Rhythms
- Harvard Business Review — HBR Ideacast Podcast. The Case for Designing Work Around Circadian Rhythms
- Crown Lighting Group. The Role of Circadian Lighting in the Workplace
- Psychology Today. Exposure to Natural Light Improves Workplace Performance
- MyShyft. The Circadian Business Advantage: Leveraging Biological Rhythms for Workplace Success
