A rolling stone gathers no moss. This simple saying also makes sense when it comes to dementia prevention. This has now been confirmed by a large number of scientific studies. New findings show that there is far more scope in the daily exercise routine than previously assumed.
Not surprisingly, the link between a sedentary lifestyle and the risk of dementia is increasingly becoming the focus of dementia prevention. In 2020, the “Lancet Commission on Dementia Prevention, Intervention, and Care” listed 12 modifiable risk factors that could contribute to the development of dementia, including physical inactivity [1].
The current World Health Organization (WHO) dementia guidelines also recommend that even adults with normal mental capacity should engage in physical activity to reduce the risk of cognitive decline [2].
But what is the right amount of exercise? How secure is the scientific research situation in this area and what should be paid attention to when other physical limitations already make manageable daily activity a major challenge?
Regular walking against dementia: The current state of science
Already in the past, numerous prevention studies have investigated the relationship of different sports activities, such as endurance training, strength training or stretching exercises on the risk of dementia. Clear dose-response relationships between the intensity of the activity and the possibility of being protected from the disease have been demonstrated.
According to a recent assessment in Lancets medical journal, 6,000 to 8,000 steps would be the desirable physical activity dose to reduce all-cause mortality. Furthermore, 10,000 steps per day is considered the “optimal” number of steps that could prevent a large number of non-communicable chronic diseases such as type 2 diabetes, obesity, hypertension, and cancer, and improve people’s quality of life [3].
Also, the current guidelines advise scheduling at least 150 to 300 minutes of moderate-intensity physical activity or 75 to 150 minutes of high-intensity physical activity per week [4].
10,000 steps per day? 5 hours of exercise per week? That’s not always feasible. But medical guidelines are generally rather rigid, and it takes quite a while for new scientific findings to find their way into the recommendations. Knowledge stops Dementia has therefore made it its task to sift through the latest study results on this topic as well, from which extended advice on dementia prevention with the help of exercise can already be derived without risk or side effects.
Can very low-intensity physical activity also help to prevent dementia?
Elderly people in particular, but also those affected by other diseases that restrict their ability to move, face a dilemma if they want to prevent dementia as efficiently as possible. After all, personal circumstances must allow for a fairly demanding exercise program in the first place. For this very reason, it is of particular interest to find out what role very low levels of physical activity play in dementia prevention.
A Korean study from 2021 investigated exactly this and found an answer to this question with more than 60,000 participants: 66.4% of the study participants had a low physical capacity. Yet, in this group, engaging in very light physical activity was associated with about a 10% lower risk of dementia compared to participants who were exclusively sedentary [5].
Furthermore, the study showed a clear, almost linear correlation between physical activity intensity and risk reduction of dementia. The metabolic equivalent MET was used to estimate the intensity of the various physical activities. The abbreviation MET comes from the English and stands for Metabolic Equivalent of Task. The group of people with the highest physical activity (with more than 1,000 MET-minutes per week) showed a 28%, the moderately active group (with 500-999 MET-minutes per week) a 20%, the slightly active group (with 300-499 MET-minutes per week) a 14% and the least active group (with 1-299 MET-minutes per week) a 10% reduction in disease risk compared to non-active participants [5].
Accordingly, ANY physical activity, even if performed at a lower intensity, would be effective in reducing physical inactivity and thus reduce the risk of dementia.
Counting steps can help prevent dementia – how long and how fast should we walk each day?
A new study published in the journal JAMA Neurology in September 2022 [6]also addresses this important topic. It shows very clearly that not only the number of steps per day, but also the step frequency, i.e. the number of steps per minute, is directly related to a lower risk of dementia.
The study looked at more than 78,000 people between the ages of 40 and 79 who wore a pedometer on their wrist 24 hours a day, 7 days a week.
The researchers then compared the pedometer data with the diagnosis of dementia made seven years later. The evaluation considered age, ethnicity, education, gender and socioeconomic status, as well as numerous lifestyle variables such as diet, smoking, alcohol consumption, medication use, sleep problems and other factors.
The results showed that a minimal amount of physical activity of about 3,800 steps per day would reduce the risk of developing dementia by 25%.
According to the study, the optimal number of steps is 9,800 steps per day and would reduce the risk of dementia by 50%, which is very close to the wildly spread popular goal of 10,000 steps per day.
Here, again, a clear dose-response is thus evident; even with lower step counts, some protection against dementia would thus be expected. Thus, dementia prevention in the population could be improved by increasing daily activity, and counting steps with a pedometer is a simple and effective way to achieve the right “exercise dose”.
10,000 steps a day are not feasible? This is what you can do instead
In the study described above [6] ), the walking performance of the participants was also analyzed. For those who walked for 30 minutes a day, it was shown that a step frequency of about 112 steps per minute could reduce the risk of developing dementia by 62%.
112 steps per minute is therefore the figure to which all those should pay attention for whom 10,000 steps a day are not feasible, and who nevertheless want to keep their brains as fit as possible. A total of 30 minutes of walking should be integrated into the day if possible, but these do not have to be completed in one piece. How you divide up your units is up to you. Thus, the study represents another important contribution to recommendations for dementia prevention. Counting steps is also a simple way to monitor performance, which is now possible with many wearable devices, including smartwatches and even cell phones.
But with all this, of course, it should not be forgotten that even 112 steps per minute can be achieved only by people without significant walking disability. Therefore, it is recommended to look for alternatives in case of such severe limitations. These can include forms of exercise such as cycling (even on a safe exercise bike) or even rowing and playing ball. Ultimately, all exercise protects against dementia to a significant degree and should be part of the daily routine as much as possible. As has been shown, even low levels of engagement produce measurable reductions in dementia risk.
Why is walking in particular so important for our (mental) health?
Genetically, we have been “programmed” to walk. Our ancestors, who lived as hunter-gatherers, covered long distances on foot in search of food. The upright posture and bipedal walking were important evolutionary milestones that made this locomotion possible. Seen in this light, walking is part of human nature. It is also no longer a secret that walking is a natural and effective way to increase NEAT (non-exercise thermogenesis/heat production) and thereby increase calorie consumption, which has a very positive effect on health and longevity.
The results of the studies make it all the clearer how far the “modern” lifestyle is from our biological nature and that we have been behaving in a way that is no longer “species-appropriate” for a long time. In other words, returning to nature and to the natural and appropriate way of life for the human species – which includes walking long distances every day – is in fact the greatest secret to preventing all “modern” diseases, not just dementia!
Conclusion
A sedentary lifestyle (or better, an immobile lifestyle) is clearly a risk factor for dementia. Exercise is therefore strongly recommended as a preventive measure. Recent studies have shown that even mild physical activity can play a role in reducing dementia risk. Therefore, even elderly people who cannot perform intense physical activities due to their frailty and concomitant diseases benefit from adapted physical exercises or even slow walks. In this way, the risk of dementia can already be slightly reduced. Counting steps is a simple way to ensure a good and efficient level of physical activity and thus prevent cognitive deterioration. 9800 steps per day at any speed or 30 minutes at a step rate of 112 steps per minute can reduce dementia risk by more than 50%. A pedometer (included in most smartwatches or even cell phone apps) makes it easy to monitor this data. For those who are unable to walk for other reasons, other forms of exercise are available. Just don’t rest too much!
References:
- ↑ Livingston G, Huntley J, Sommerlad A, Ames D, Ballard C, Banerjee S, Brayne C, Burns A, Cohen-Mansfield J, Cooper C, Costafreda SG, Dias A, Fox N, Gitlin LN, Howard R, Kales HC, Kivimäki M, Larson EB, Ogunniyi A, Orgeta V, Ritchie K, Rockwood K, Sampson EL, Samus Q, Schneider LS, Selbæk G, Teri L, Mukadam N. Dementia prevention, intervention, and care: 2020 report of the Lancet Commission. Lancet. 2020 Aug 8;396(10248):413-446. doi: 10.1016/S0140-6736(20)30367-6. Epub 2020 Jul 30. PMID: 32738937; PMCID: PMC7392084.
- ↑ World health Organization, Risk reduction of cognitive decline and dementia 2019 https://www.who.int/publications/i/item/risk-reduction-of-cognitive-decline-and-dementia
- ↑ Paluch AE, Bajpai S, Bassett DR, et al; Steps for Health Collaborative. Daily steps and all-cause mortality: a meta-analysis of 15 international cohorts. Lancet Public Health. 2022;7(3):e2
- ↑ World Health Organization. WHO guidelines on physical activity and sedentary behaviour. https://www.who.int/publications/i/item/9789240015128
- ↑ M Yoon, PS Yang, MN Jin, HT Yu, et al.Association of physical activity level with risk of dementia in a nationwide cohort in Korea JAMA Netw Open. 2021 Dec; 4(12): e2138526.
- ↑ Del Pozo Cruz B, Ahmadi M, Naismith SL, Stamatakis E. Association of Daily Step Count and Intensity With Incident Dementia in 78 430 Adults Living in the UK. JAMA Neurol. 2022 Oct 1;79(10):1059-1063. doi: 10.1001/jamaneurol.2022.2672. Erratum in: JAMA Neurol. 2022 Sep 9;: PMID: 36066874; PMCID: PMC9449869.
