You opened your laptop at 9am, fired up your AI assistant, and spent the next eight hours being wildly productive. You wrote code, summarized docs, drafted three emails, generated test cases, and reviewed AI output like a benevolent but increasingly frantic quality inspector. It’s 6pm and You haven’t stopped, but completely, thoroughly, inexplicably exhausted.
Congratulations. You are not alone.
“At first, employees felt energized, their productivity soared. But over time, the workday quietly stretched longer to a prompt during lunch, one last query before leaving the office, while the number of breaks decreased.”
Nobody asked these workers to do more. No manager added items to the sprint. The AI just made more possible, so more got done, silently, incrementally, until fatigue started eroding the very decision quality that made them valuable in the first place.
Researchers called this “workload creep.” The rest of us might call it a “Tuesday”.
Meet your new enemy: “AI brain fry”
Researchers at Boston Consulting Group surveyed nearly 1,500 U.S. workers and discovered a delightful new condition to add to the modern worker’s lexicon. They call it “AI brain fry” defined as mental fatigue from the excessive use or oversight of AI tools beyond one’s cognitive capacity. Symptoms include mental fog, headaches, a persistent “buzzing” sensation, difficulty focusing, and slower decision-making that gets worse as the day goes on.
14%
of high-oversight AI users experience “brain fry”
3
AI tools is the magic number – a 4th one tanks productivity
77%
of workers say AI actually added to their workload
Sources: BCG Henderson Institute (2026), Upwork/Harvard Business School survey
The cruelest irony? The people hit hardest are often your best, most motivated engineers – the ones who actually experiment with AI tools, adopt them eagerly, and push their workflows to the limit. They’re not burning out from boredom. They’re frying from enthusiasm.
As Illia Smoliienko, a software leader writing in Fast Company, put it: developers started writing code faster and getting answers in seconds – yet reported feeling more exhausted than before. AI hadn’t reduced the work. It had changed its nature. You’re no longer the doer. You’re the one checking, comparing, and choosing. You are, effectively, the AI’s manager. And managing is exhausting.
“Eventually, managing tools and constantly switching between them becomes more draining than performing the original tasks themselves.”
– Fast Company
The Ferrari problem
BCG’s Matthew Kropp offered a metaphor that will resonate with anyone who’s ever juggled four AI tabs simultaneously: managing multiple AI agents is like handing a brand-new driver a Ferrari. You can go really fast but losing control is very easy.
The promise of AI was always that the machines would do the grunt work so humans could focus on the meaningful stuff. The bottleneck was never compute power. It was always human attention, and human attention doesn’t scale on demand. If your team is moving faster but feeling worse, you don’t have a productivity problem. You have a workflow design problem. And that one, at least, is still a very human job.
This post is based on “How AI is quietly exhausting you – and what to do about it” by Illia Smoliienko, Fast Company (April 2026), with supporting data from BCG Henderson Institute, UC Berkeley, and Upwork/Harvard Business School research.
