Exercise and the brain: a moderate weekly dose gave the best gains for thinking

Brisk walking most days of the week is a great fit for your brain. That is the takeaway from new research on exercise and the brain: a moderate amount of exercise gave older adults with mild memory problems the most reliable gains in thinking skills.

You do not need to go all out. In this research, the sweet spot was a steady, moderate routine, and doing a lot more did not add to the benefit.

How the study worked

Researchers pooled the results of many randomized trials of repeated exercise programs. The people in them were adults aged 60 or older with mild cognitive impairment, which means memory or thinking problems that you notice but that do not yet get in the way of daily life much. The work was a network meta-analysis, a way of comparing many studies and many types of exercise side by side, and it appeared in PeerJ on October 20, 2026. The certainty of the evidence ranged from low to moderate, and the authors call for future trials that test several exercise amounts directly.

What they found

The team looked at three mental skills, often grouped as executive function. They are working memory (holding information in mind), cognitive flexibility (switching between tasks) and inhibitory control (staying focused and holding back impulses).

For all three, the gains followed a curve instead of a straight line. Benefits grew as people exercised more, then leveled off. The most reliable gains showed up at moderate doses, about 300 to 1,000 METs-min per week (the exact range in the abstract is 300-1,000 METs⋅min/week). Higher amounts showed plateaus or small declines.

The type of exercise mattered a little too:

• Exercise paired with mental training, such as moving while doing a thinking task, gave the most consistent gains in working memory.
• Walking for aerobic exercise gave steadier effects on flexibility and focus.
• Comprehensive physical training, a mix of exercise types, did the same.

The authors also ran extra checks, and the results held up. Publication bias was minimal.

What is a MET-minute?

A MET-minute is a simple way to count both how hard and how long you move. Harder activities count for more each minute. A brisk walk is a classic example of moderate effort, so regular brisk walking across the week is a practical way to build a moderate weekly total.

What you can do today

Take a brisk walk today, at a pace where you can talk but not sing. Repeat it on most days this week. On one of those walks, add a little mental challenge, such as naming animals or foods from A to Z as you go.