Exercise for brain health: This is the exact amount of exercise required per week to sharpen memory, increase brain power |

In an age when brain fog, forgetfulness, and digital overload are common, science keeps pointing to one simple, powerful medicine, exercise. Beyond building muscles or burning calories, regular movement can physically reshape the brain and sharpen memory. According to the World Health Organization (WHO), over 1 in 4 adults globally are not active enough, leading not only to physical but also mental decline. And that’s where neuroscientists like Dr Wendy Suzuki, a leading brain researcher at New York University, bring clarity: exercise isn’t just good for the body, it literally changes the brain’s structure and performance.

Dr Wendy Suzuki’s research, as shared on The Diary Of A CEO podcast, reveals something remarkable: every drop of sweat strengthens the brain. In her lab studies, even participants who moved their bodies for 45 minutes, two to three times a week, showed measurable improvements in memory, mood, and focus. This happens because exercise increases blood flow to the brain and stimulates the hippocampus, the region responsible for learning and memory.

Over time, consistent workouts make the hippocampus stronger and thicker, almost like growing “mental muscles.” This means clearer thinking, faster recall, and a sharper sense of focus in everyday tasks.For those not used to exercise, Suzuki’s team discovered a very hopeful number: two to three 45-minute aerobic sessions a week. That’s enough to begin changing how the brain functions. These sessions can include cycling, brisk walking, swimming, or dancing, anything that raises the heart rate and keeps it there steadily.Within a few weeks, participants reported better memory retention and a noticeable lift in mood. The beauty of this discovery is that the brain responds to movement much faster than expected, it doesn’t need months to notice improvement; even a few weeks can make a real difference.While two or three sessions are a great start, Suzuki’s second study revealed something even more exciting. Among regular exercisers, the more they moved, the greater the brain benefit. Those who increased activity up to six or seven days a week experienced continuous improvements in hippocampal growth, prefrontal function (decision-making and planning), and mood.

In practical terms, this means around 4-5 total hours of aerobic exercise per week is an ideal target for sharper memory and stronger cognitive control. That could be 45 minutes daily for five days, or longer, lighter walks mixed with occasional intense workouts.

Aerobic workouts stand out because they flood the brain with oxygen and trigger the release of brain-derived neurotrophic factor (BDNF), a kind of “fertilizer” for brain cells. BDNF helps neurons grow stronger and connect better, improving learning and recall.Regular exercise also lowers the levels of stress hormones like cortisol, which can otherwise shrink brain regions responsible for memory. In other words, every jog, spin class, or dance session helps the brain defend itself against ageing and stress while staying alert and adaptable.

One of Suzuki’s most heartwarming findings is how mood improvement precedes cognitive gains. When exercise lifts emotional state, by releasing endorphins and serotonin, the brain becomes more ready to absorb and store information. Happiness, it turns out, sharpens focus.This might explain why many people find their most creative or clearest thoughts appear after a workout. The emotional uplift primes the brain to remember and problem-solve better, creating a powerful loop of motivation.

Perhaps the most comforting insight from Suzuki’s research is that there’s no wasted effort. Even short bursts of physical activity, climbing stairs, dancing while cooking, or a brisk 15-minute walk, contribute to brain growth. The key is consistency, not perfection.Over time, these small moments of movement add up, helping the brain become, as Suzuki puts it, “big, fat, and fluffy,” meaning healthy, resilient, and full of life.Disclaimer: This article is meant for informational purposes only and is not a substitute for professional medical advice. Anyone with existing health conditions should consult a certified healthcare provider before starting or changing an exercise routine.