Acute effects of movement

Last week, we looked at how regular exercise, over time, might help shape the brain in an advantageous way, time by influencing brainwaves and neurochemicals.

This week, we're shifting the focus to the more immediate, short-term effects. 

We’ll look at how breaking up long hours of sitting at the office can support better focus and brain function. And we’ll also look at how just one session of exercise can directly impact the brain’s activity and performance.

Today’s insights are mainly drawn from three different scientific articles:

“Acute effect of breaking up prolonged sitting on cognition: a systematic review” Ting-Yu Chueh et al, 2022

“A scoping review of effects of acute exercise on executive function: evidence from even related potentials” Zhidong Cai et al, 2025

“Effect of frequent interruptions of prolonged sitting on self-perceived levels of energy, mood, food cravings and cognitive function” Audrey Bergouignan et al, 2016

Today's newsletter

• Takeaways:

• Breaking up the long hours of sitting:

• Short frequent breaks:

• Acute effects of exercise:

• What can we learn from these studies?

Takeaways:

🥇 Frequent short activities is beneficial for mood, energy and gravings

Breaking up your long sitting workdays with short 5-minute walks each hour can lead to better mood, more energy, and fewer cravings throughout the day.

⚡ Exercise sharpens your brain's attention system

After moderate-intensity exercise, the brain's P3 signal, which reflects focus and decision-making, becomes stronger and faster. This suggests your brain is more alert and ready to process important information.

Breaking up the long hours of sitting:

The main study of today, is a systematic review, that explored whether interrupting prolonged sitting with short bouts of physical activity, can enhance cognitive performance in healthy individuals.

The researchers analyzed seven randomized crossover trials involving 168 participants in the ages of 18 to 80.

Overall, the findings were mixed, and there was a high degree of heterogeneity across the included studies.

However, three of seven included studies showed clear benefits from interupting prolonged sitting;

1) Moderate-intensity walking for three minutes every 30 minutes improved attention and inhibitory control in young adults
2) Long, low-intensity breaks (10–30 minutes every hour) improved attention, working memory, and cognitive flexibility in adults with obesity
3) Combining an initial 30-minute bout of moderate-intensity exercise with light walking breaks spread throughout the day, enhanced working memory in older adults.

The review suggests that the intensity, frequency, and duration of the activity breaks matter.

Moderate-intensity movement tends to be more effective than light activity, and shorter but more frequent breaks seem more beneficial than longer, infrequent ones.

Interestingly, simply standing or doing very light exercises like calf raises did not lead to cognitive improvements.

The authors argue that the mechanisms behind the cognitive benefits include improved regulation of norepinephrine and glucose.

Using small breaks with physical activity may help prevent the cognitive dulling associated with extended periods of sedentary behavior by stabilizing blood glucose and enhancing cerebral blood flow.

While I want to stress that identifying trends from such a diverse review with a relatively small amount of studies should be done with caution, the findings might still suggest a potential benefit to our mental energy and performance from interrupting prolonged periods of sitting.

This potential benefit is nicely illustrated in the following study.

Short frequent breaks:

This second study that I want to include today, explored how breaking up sitting time with short periods of physical activity impacts energy, mood, food cravings, and cognitive function in sedentary adults.

Thirty participants completed three conditions: 

1) Uninterrupted sitting (SIT)
2) One 30-minute morning walk (ONE)
3) 5-minute walks each hour (MICRO).

Both ONE and MICRO improved self-perceived energy and vigor. However, only MICRO significantly enhanced mood, reduced fatigue, and lowered food cravings by the end of the day.

Although cognitive performance remained unchanged across all conditions, these findings do suggest that breaking up prolonged sitting with shorter and somewhat frequent periods of physical exercise, improves the feeling of mental energy.

Acute effects of exercise:

With the last study, I want to look into the potential acute benefits of a longer bout of physical activity. Physical activity that more closely resembles an exercise session rather than simply the breaking up of sedentary periods.

This review looks at how a single session of physical activity can affect executive function, which is the set of mental skills that help us plan, focus, stay organized, manage our emotions, and make decisions.

To understand this, the researchers examined brain signals called event-related potentials, which are measured using EEG

The review included 52 studies and found that:

- After exercise, the P3 brain signal became stronger in most studies. This signal is linked to attention and decision-making, so a stronger P3 suggests the brain is more focused and better at processing important information. Some studies also found it happened faster, meaning quicker mental responses. 

- Other brain signals, like N2 and N1, also showed some improvement.
- N2 is related to detecting conflict or making decisions when something unexpected happens.
- N1 reflects early attention; how quickly the brain notices a new sound, image, or event.

- These positive effects on the brain are short-lived and tend to peak about 15–30 minutes after exercising.

What can we learn from these studies?

Although the research is still a bit limited and mixed, the overall pattern suggests that breaking up long periods of sitting could boost brain performance and support mental vitality.

In today’s typical work environments, many of us spend most of the day sitting.

I know I definitely feel the slow drain, the numbing and tired feeling, when I sit for hours without moving.

Personally, I perform much better on days when I manage to get up, move around, or fit in some short activity breaks.

Maybe the same could work for you?

Try breaking up those long periods of sitting at your desk. It seems that smaller and more frequent activities of moderate effort might be the best.
See if it makes a difference in your mental energy and focus.

Meanwhile, it seems clear that an actual exercise session leads to real cognitive improvements.

The acute effects are short lived though, so it might be difficult to implemented exercise as a routine where you try to use the immediate benefits.

_{Disclaimer: The above is mainly based on the 4 articles mentioned in the beginning of this newsletter, and aims to provide key takeaways and a condensed overview of its content. While the essence is drawn from the original articles, some parts have been simplified or rephrased to enhance understanding. Please note that we at, OptiMindInsights or any other potential writers or contributors to our summaries, do not accept responsibility for any consequences arising from the use of these summaries and/or newsletters as a whole. The information provided should not be considered a substitute for personal research or professional advice. Readers are encouraged to consult the original articles for detailed insights and references. The summary does not include references, but they can typically be found within the original publication. Always exercise due diligence and consider your unique circumstances before applying any information in your personal or professional life. We refer to the creative commons for reproducibility rights.}