Swap the task, don't push through

In one study, about forty people spent a working day on either hard or easy mental tasks. By the end, the hard-work group had more glutamate, a chemical brain cells use to signal each other, in the prefrontal cortex, the front of the brain that plans and weighs options. They also chose less effort and quicker rewards more often. Evidence: worth trying

That's one study, one day, lab tasks, and other researchers have questioned how it was measured. The mechanism is interesting, not settled. It's also not the old willpower tank, which failed its big tests. The idea here is narrower: a build-up in one part of the brain, not a reserve you ration.

The takeaway is mine, and nobody has tested it: when hard work stops moving, grinding on gets you worse work and worse choices. Switch to email, filing, calls that need no thought. Anything that needs judgement waits. Evidence: worth trying