Next Article in Journal
Investigation of Waste Steel Fiber Usage Rate and Length Change on Some Fresh State Properties of 3D Printable Concrete Mixtures
Previous Article in Journal
A Study of a Noncontact Identification Method of Debonding Damage in External Thermal Insulation Composite Systems Based on Nonlinear Vibration
Previous Article in Special Issue
Generative AI for Architectural Façade Design: Measuring Perceptual Alignment Across Geographical, Objective, and Affective Descriptors
 
 
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Article

Brain Booster Buildings: Modelling Stairs’ Use as a Daily Booster of Brain-Derived Neurotrophic Factor

by
Mohamed Hesham Khalil
* and
Koen Steemers
Neurocivitas Lab, Department of Architecture, University of Cambridge, Cambridge CB2 1PX, UK
*
Author to whom correspondence should be addressed.
Buildings 2025, 15(20), 3730; https://doi.org/10.3390/buildings15203730
Submission received: 10 September 2025 / Revised: 6 October 2025 / Accepted: 14 October 2025 / Published: 16 October 2025
(This article belongs to the Special Issue BioCognitive Architectural Design)

Abstract

This paper establishes the Brain Booster Buildings framework, the first model to demonstrate how daily stair use can elevate brain-derived neurotrophic factor (BDNF), a vital molecule for lifelong neurogenesis and brain health in humans. Through a novel framework of the associations between metabolic equivalents (METs) data and BDNF response studies, we establish that stairs are generally higher in METs than any indoor activity. We further explain how architectural parameters (riser height, floor number, pace) predictably modulate exercise intensity during stair use. We identify two implementable patterns: moderate-intensity continuous use (≥20 min, 1–3 floors) and high-intensity interval training (6 min, carrying loads while using stairs in a building with three floors or less, or using stairs in a building with ≥3 floors, load-free). Based on BDNF responses to comparable exercise intensities, 6 min of high-intensity stair climbing is predicted to increase serum BDNF by up to 40%. Since people spend ~90% of their time indoors while neurogenesis declines fourfold throughout the adult lifespan, affecting mood, stress resilience, and memory, vertical architecture emerges as a vital, accessible, and cost-effective infrastructure that boosts BDNF for neurogenesis, plasticity, and brain health. We conducted scenario-based modelling using the Brain Booster Buildings framework to estimate how the use of stairs in residential, office, educational, hospital, and commercial buildings may boost BDNF levels based on established intensity–BDNF relationships. The framework provides architects, policymakers, and clinicians with evidence-based estimated specifications to use buildings as daily brain boosters.

1. Introduction

Mood, memory, and stress represent growing major health challenges, yet interventions often overlook the simplest environmental elements accessible to almost everyone. While pharmaceutical and behavioural treatments dominate clinical approaches, emerging evidence suggests that stairs can offer untapped neurobiological benefits. This paper establishes the Brain Booster Buildings framework, demonstrating how stair use, a ubiquitous yet underutilised building feature, may sustainably elevate brain-derived neurotrophic factor (BDNF) to support brain health and functions. BDNF is vital for mood regulation, resilience to chronic stress, brain health, and lifelong neuroprotection [1,2,3,4,5,6,7,8,9,10,11]. Boosting BDNF can be sustainably achieved through short, repeated bouts of moderate-to-high-intensity physical activity [12,13,14,15].
BDNF is a central molecular mediator of human neuroplasticity and neurogenesis, which is boosted through physical activity [16,17,18,19]. After decades of researching how to enhance adult hippocampal neurogenesis (AHN) in the brains of rats and mice through running wheel-based voluntary physical activity, AHN has finally been evidenced to persist in the human brain as well until the tenth decade of life [20,21,22,23], where ~700 new neurons are generated daily in each of the left and right hippocampus, but the decline is fourfold throughout the lifespan [24]. Exploring how to boost BDNF in humans for AHN, stress resilience, mood regulation, memory consolidation, and cognitive function has become a vital necessity.
While urban environments can afford walking and cycling activities (e.g., moderate-to-vigorous intensity walking and cycling) [25], air pollution in urban environments can impair the increase in BDNF [26,27]. Indoors, however, the energy costs of activities inside buildings often cluster between 1.0 and 1.3 metabolic equivalents (METs) for passive postures, such as lying quietly, habitual television watching, and standing, while indoor walking is unlikely to exceed 2.3 METs, as stated in the latest 2024 Adult Compendium of Physical Activity [25]. This problem becomes critical, especially when people spend around 90% of their time indoors [28], and the number of hours spent indoors has increased since then over the past couple of decades (by 1 h and 39 min in a typical day in the US between 2003 and 2022) [29], with a notable acceleration during and since COVID-19 [30,31].
However, direct evidence of BDNF responses specifically to stair climbing remains limited, and this framework relies on extrapolation from studies of walking and cycling at comparable intensities [32]. This hypothesis is supported by recent evidence showing that 20 min of activity at 3.5 METs can significantly increase BDNF levels immediately [33]. Still, the mechanism by which stair use can increase BDNF is not fully understood. Thus, this paper establishes the first theoretical framework, the Brain Booster Buildings framework, which explains and estimates how stair use can increase BDNF levels in blood serum as an acute change following brief daily stair use.

2. Materials and Methods

Based on a conceptual framework (Figure 1), we achieved the aim of this study by accomplishing the following objectives:
  • Explore the associations between metabolic equivalents (METs) and both stairs and stair use parameters. This objective is accomplished through a narrative literature review using search terms ‘stair *’, ‘metabolic equivalents’, and METs in the Scopus database and Google Scholar for studies published between 1995 and 2025. We only included English-language studies on healthy adults to avoid any confounding variables at this stage. Studies must report acute METs explicitly, and with objective measures. They must report the number of flights or floors if not reporting METs associated with carrying loads upstairs. The first objective is to establish an association between the predictive outcome of METs and both staircase parameters (e.g., number of floors) and stair use type (e.g., ascending stairs, descending stairs, or both).
  • Explain the potential association between staircase parameters (e.g., number of floors and riser height) and the METs outcome to inform architectural design.
  • Explore the association between physical activity intensities (low intensity < 3 METs, moderate intensity = 3–6 METs, and high intensity > 6 METs) and acute changes in BDNF levels. Due to the lack of meta-analyses, this objective was achieved through a narrative review of the acute changes in BDNF in response to different types of activity.
  • Establish the ‘Brain Booster Buildings’ theoretical framework that can estimate increases in BDNF levels according to the recommended duration of stair use to inform policymakers and lifestyle medicine.
  • Conduct scenario-based modelling using the Brain Booster Buildings framework to estimate the BDNF changes in three scenarios (1, 3, and >3 floors) for each building type (residential, educational, office, hospital, and commercial).

3. Staircase Affordances for Metabolic Equivalents (METs)

A promising approach to how voluntary physical activity can boost BDNF levels in humans, and potentially promote neurogenesis, is by examining environmental affordances for metabolic equivalents (METs), which account for the intensity and duration of physical activity achieved through the use of an environment [32]. For adults and older adults, sedentary behaviours are defined within the range of 1.0–1.5 metabolic equivalents (METs), light-intensity physical activity as 1.6–2.9 METs, moderate-intensity physical activity as 3.0–5.9 METs, and vigorous-intensity physical activity as ≥6.0 METs [25,34]. Those ranges are used as standards in research for public health by the World Health Organisation [35].
The Adult Compendium of Physical Activity defines household walking as 2.3 METs [25], which is significantly below the moderate-intensity physical activity threshold (3 METs). On the contrary, stair use is defined as higher in METs also as per the Adult Compendium for Physical Activity, where descending stairs is defined as 3.5 METs, while ascending stairs is defined as 4.5 METs for a slow pace (4.0 METs for older adults), 6.8 METs for a general pace, and 9.0 METs for a fast pace [25,34].
A summary of the literature found on stair-use-based METs is presented in Table 1, which shows more nuanced differences.
A study by Teh & Aziz [36] in an 11-storey building showed that ascending and descending 11 stories (180 steps at a 15 cm riser height) are defined as 9.6 and 4.9 METs, respectively. Participants took 99 ± 14 steps per minute to ascend and 103 ± 9 steps per minute to descend. Secondly, in a 5-storey building, ascending five floors (at 10 cm riser height) by young adults has a METs value of 6.18 ± 1.08 [37], while a higher riser (100 steps at 17.3 cm riser height) was equivalent to 7.55 ± 1.32 METs by a group of a similar age range [38]. Comparing the two studies reveals that riser height is the primary factor in determining METs, not just the number of floors. In the study by Al Kandari et al. [38], it took participants 2 min on average to reach the fifth floor, where METs increased to around 7.6 METs by the fifth floor. This shows that the impact of the pace of climbing stairs on METs is the second critical factor, as introduced per the Compendium earlier since it took participants in the study by Teh & Aziz [36] the same duration (around 2 min) to climb a 27 m building compared to the 17.3 m height building in the study by Al Kandari et al. [38]. After 10 min of rest, descending from the fifth floor was equal to around 3 METs. It increased until reaching approximately 3.6 METs at the end of continuously descending the five floors [38], which is similar to the 3.5 METs reported in the Adult Compendium of Physical Activity [25]. However, it also shows that the time varies based on the number of floors ascended. Thirdly, Yue et al. [39] studied METs in two groups of young adults (<60 years) and older adults (≥60 years old) who climbed up and down two flights of stairs four times in a 3-storey building. They found that it took young adults 1.96 ± 0.29 min to complete the task, whereas it took older adults 2.96 ± 0.14 min, which can be classified as a slow pace in both groups. It corresponded to 3.8 ± 0.68 METs in young adults and 2.9 ± 0.73 METs in older adults. This study demonstrates that pace and the maximum number of floors influence the final MET value while confirming that age also affects METs.
Defining stair ascendance through METs depends on the number of floors and gender differences. In the study by Al Kandari et al. [38], males and females began near resting levels (1.74 and 1.40 METs, respectively). By the 1st floor, both reached 3.47 METs. On the 2nd floor, males reached 5.80 METs while females were slightly lower at 4.81. By the 3rd floor, this reversed: females climbed to 6.73 METs, surpassing males at 6.28. The difference widened at the 4th floor, with females reaching 7.45 METs and males 6.55. On the 5th floor, both sexes converged around 7.6 METs. Despite similar peak METs, females consistently showed higher heart rate reserve percentages, meaning they worked harder relative to their capacity. Notably, females reached effective training intensity by the 3rd floor, whereas males typically needed to climb all five floors or increase their pace to reach a comparable effort. This illustrates how stair climbing intensity increases floor by floor, with meaningful sex-specific differences.
Accordingly, we were able to synthesise a few studies to theoretically estimate prospective ascending-and-deadening-associated METs based on the number of floors, as shown in Figure 2 and Figure 3, respectively. We were also able to estimate the change in METs based on the stair riser height by synthesising another couple of studies, as illustrated in Figure 4.
Figure 2. Predicted stair ascent METs based on reported METs in Teh & Aziz [36] and Al Kandari et al. [38] where riser height is 15 cm and 17.3 cm, respectively, after re-estimating the floor number in Teh & Aziz [36] based on the total height to fit on the same axis.
Figure 2. Predicted stair ascent METs based on reported METs in Teh & Aziz [36] and Al Kandari et al. [38] where riser height is 15 cm and 17.3 cm, respectively, after re-estimating the floor number in Teh & Aziz [36] based on the total height to fit on the same axis.
Buildings 15 03730 g002
Figure 3. Predicted stair descent METs based on reported METs in Teh & Aziz [36] and Al Kandari et al. [38] where riser height is 15 cm and 17.3 cm, respectively, after re-estimating the floor number in Teh & Aziz [36] based on the total height to place on the same plot graph.
Figure 3. Predicted stair descent METs based on reported METs in Teh & Aziz [36] and Al Kandari et al. [38] where riser height is 15 cm and 17.3 cm, respectively, after re-estimating the floor number in Teh & Aziz [36] based on the total height to place on the same plot graph.
Buildings 15 03730 g003
Table 1. Summary of available literature on METs and stair use without carrying loads.
Table 1. Summary of available literature on METs and stair use without carrying loads.
Subject Physical CharacteristicsStairs CharacteristicsStair UseTotal DurationMETs
AgeWeight (kg)Height (m)Pace (Steps·Min−1)Riser Height (cm)Total StepsFloors/Flights (Above Ground)
Staircase
Teh & Aziz [36]M: 44.8 ± 13.9
F: 43.2 ± 12.9
M: 66.2 ± 10.6
F: 54.4 ± 7.2
M: 1.68 ± 0.5
F: 1.58 ± 0.5
Brisk pace -
Ascent:
M: 99 ± 14
F: 90 ± 14
Descent:
M: 103 ± 9
F: 110 ± 17
1518011 floors
(22 flights)
Ascent and descentAscent:
116 ± 18 s
Descent:
106 ± 14 s
Ascent:
M: 9.9
F: 9.2
Descent:
M: 4.6
F: 5.1
Yue et al. [39]Young adults
M: 28.7 ± 7.5
F: 25.9 ± 7.7
Older adults
M: 72.7 ± 7.1
F: 71.1 ± 6.0
Young adults
M: 63.2 ± 9.2
F: 54.6 ± 9.9
Older adults
M: 63.7 ± 8.0
F: 56.4 ± 8.4
Young adults
M: 1.72 ± 0.08
F: 1.58 ± 0.08
Older adults
M: 1.64 ± 0.06
F: 1.52 ± 0.05
Preferred or normal speed2 flightsAscent and descent
× 4 times
(Ascent and descent)
Young adults:
1.96 ± 0.29 min
Older adults:
2.96 ± 0.14 min
(Ascent and descent)
Young adults:
3.8 ± 0.69
Older adults:
2.9 ± 0.73
Cho et al. [37]31.0 ± 4.967.9 ± 12.9169.3 ± 6.9Railing use is allowed105 floorsAscent6.18 ± 1.08
Al Kandari et al. [38]M: 33.6 ± 10.53
F: 30.93 ± 19.69
M: 82.27 ± 13.04
F: 67.93 ± 10.99
M: 1.72 ± 0.05
F: 1.59 ± 0.08
Natural pace17.31005 floors
(est. 10 flights)
Ascent and descentAscent:
2 min
Descent:
2 min
Ascent:
M: 7.55 ± 1.32
F: 7.58 ± 0.99
Descent:
M: 3.19 ± 2.78
F: 3.62 ± 0.61
Figure 4. Predicted stair ascent METs based on riser height when time is constant (2 min) in the studies by Cho et al. [37] and Al Kandari et al. [38].
Figure 4. Predicted stair ascent METs based on riser height when time is constant (2 min) in the studies by Cho et al. [37] and Al Kandari et al. [38].
Buildings 15 03730 g004

4. Physical Activity, METs and BDNF

We can estimate the impact of each of the two possible types of stair-use-based voluntary physical activity on BDNF, moderate-intensity continuous exercise (MICE) and high-intensity interval training (HIIT), based on current evidence on acute changes in BDNF in response to physical activity of various intensities among young adults (Table 2). As we mentioned earlier, for adults and older adults, sedentary behaviours are defined within the range of 1.0–1.5 metabolic equivalents (METs), light-intensity physical activity as 1.6–2.9 METs, moderate-intensity physical activity as 3.0–5.9 METs, and vigorous-intensity physical activity as ≥6.0 METs [25,34]. Those ranges are used as standards in research for public health by the World Health Organisation [35].
MICE is a specific type of cardiovascular exercise performed at moderate intensity for a sustained duration (usually 20–60 min) without breaks. Its intensity ranges from about 55–70% of the maximum heart rate [40], 60–65% of maximal oxygen consumption (VO2max), or 65% of the maximum power output [41]. For example, 20 min of moderate-intensity physical activity (3.5 METs) in a gardening activity increased BDNF [33]. A single bout of 30 min of walking at a moderate speed (40–60% heart rate reserve) by both pregnant and non-pregnant women also significantly increased BDNF [42]. On the contrary, other studies found that prolonged lower-intensity walking for less than 5 h (such as an 18-hole golf round, Nordic walk, or 6 km walk) failed to significantly increase BDNF [43,44], as also shown in a systematic review of BDNF increase through walking [14].
HIIT involves repeated bouts of high-intensity effort (greater than 6 METs) alternated with recovery periods (rest). HIIT’s work intervals can be around 85–95% of HRmax [45], or VO2max of 85–100% (2–6 min) or 100–115% (10–60 s) workout, alternating with recovery intervals at 50–60% VO2max [46,47]. The duration of a HIIT-based stair use can be estimated based on the available evidence of BDNF response to a HIIT-based cycling activity. In a study by Gibbons et al. [48], just six 40 s work bouts performed at ~100% VO2peak and separated by 20 s of light pedalling (total session time ≈ 6 min, high-intensity work time = 4 min) produced a four- to fivefold rise in both plasma and serum BDNF in young, healthy adults. A stair-use-based HIIT to boost the brain by increasing BDNF is estimated to be effective as short as 6 min, but arguably not more than 20 min, since a shorter bout (20 min) of HIIT was found to be more effective than a 30 min bout [49].
Table 2. The impact of walking and cycling of various intensities on acute changes in BDNF among young adults.
Table 2. The impact of walking and cycling of various intensities on acute changes in BDNF among young adults.
StudySample Size (Young Adults up to 35 yrs)Sample CharacteristicsBDNF (Serum/Plasma)PA Intensity and DurationDelta (BDNF Δ (Baseline → Final)—Moderate Intensity (3–6 METs)Delta (BDNF Δ (Baseline → Final)—High Intensity (>6 METs)
Within-person
Gibbons et al. [48]12 (6 males; 6 females)Aerobically fit and healthy;
30 ± 10 years; BMI < 25
Plasma and serum90 min light-intensity + 6 min high-intensityPlasma = +250%
Serum = +40%
Marquez et al. [50]26 malesActive and healthy; 28 ± 5 years;serumHIIT:
0 → 6 min: ~+900 pg/mL
0 → 20 min: ~+3900 pg/mL
Cont.:
0 → 6 min: ~+1700 pg/mL
0 → 20 min: ~+1800 pg/mL
Between-person
Hutchinson et al. [42]30 females30.2 ± 4.3 years; BMI 18.5–29.9serumModerate intensity walking
40–60% heart rate reserve (HRR) for 30 min (excluding 2 min. warmup
~+300 pg/mL (pregnant women)
~+1700 pg/mL (non-pregnant women)
Goulet et al. [51]13 malesActive and healthy; 22 ± 3 years; 79.2 (9.3) kgserum180 min. Moderate intensity walking (in a 32 °C environment)~+1000 pg/mL (similarly in the old adults group)

5. The Brain Booster Buildings: A Theoretical Framework

Based on the evidenced association between METs and BDNF [33], and extrapolating from walking and cycling studies to stair climbing at comparable intensities, we propose a theoretical framework that estimates how stair design and use may support BDNF elevation and, potentially, neuroplasticity. This Brain Booster Buildings framework demonstrates that vertical architecture can be engineered to deliver neurogenic stimuli by converting daily stair use into a lifestyle medicine that can boost BDNF in the human brain, as explained in Table 3 and conceptually illustrated in Figure 5 and Figure 6.
For stair use to be classified as MICE, it requires continuous ascent and descent of 1 to 3 stories above the ground floor for a minimum of 20 min, possibly while performing daily moderate-intensity chores, for applicability. A busy morning, meal-prepping lunchtime, or cleaning at a 2-storey house can easily help reach >3.0 METs in at least 20 min. To support this, architects are recommended to separate functionally related spaces across different floors and to reduce spaciousness in spaces next to stairs to reduce low-intensity interruptions of effective voluntary physical activity that can increase BDNF.
A building does not have to have five floors for stair use to allow HIIT-based use. While ascending one floor is defined as 3.5 METs compared to 7.5 METs after reaching the fifth floor [38], the Adult Compendium of Physical Activity reports that moving household items upstairs while carrying boxes or furniture starts from 5.5 METs [25]. One study was found to report the METs associated with carrying loads upstairs. A study by Li et al. [52] on young to middle-aged Chinese adults found that carrying groceries or loads (5–20 lb) in an apartment or at home with moderate effort was equivalent to 5.3 (0.6) and 5.6 (0.9) kcal/min, respectively. The latest Adult Compendium for Physical Activity defines carrying loads of similar weight to 5.5–6.0 METs [25], which is quite similar to the reported values [52].
Collectively, these stair design variables can facilitate increasing BDNF through indoor voluntary physical activity in different building types, as explained in Table 4, Table 5, Table 6, Table 7 and Table 8, which can support neuroplasticity and AHN in humans throughout life, sustain cognitive function, and support mental health.

6. Discussion

Stair use can be vital for the human brain, and everyday stair use is likely to boost BDNF that is responsible for nurturing all essential brain functions including neurogenesis. The framework introduced in this paper is applicable for all building types, useful for different lifestyles, and provides useful guidelines for architects and policymakers where stairs no longer should only be used for emergencies or skipped for the elevator. At homes and in workplaces, schools, hospitals, shopping malls, and more building types, the staircase is often present and it offers cost-free brain-boosting therapy on a daily basis.
The Brain Boosting Buildings framework developed in this paper provides a predictive framework for both METs and BDNF changes. While this framework has developed predicted associations for riser height and number of floors, it emphasises that stair use remains the most important factor for the human brain. Still, architects can make stair use appealing by enhancing visibility, daylight, staircase design, visual aesthetics, and the spatial experience itself.
This framework also supports the recent recommendations on designing buildings with stairs to reduce the risk of mortality. Stair use at home is a low-cost intervention for reducing disease risk in public health [53], and the presence of stairs at home also reduces the risk of mortality [54]. Climbing more than five flights of stairs daily (approximately 50 steps) lowers the risk of atherosclerotic cardiovascular disease (ASCVD) types by 20% [55].
Stair use can also help meet the recommended minimum weekly physical activity. The British Heart Foundation (BHF) recommends 150 min of moderate-intensity physical activity per week [56]. In the United Kingdom, the National Health Service (NHS) provides a 75 min equivalent of vigorous-intensity physical activity per week [57]. The American College of Sports Medicine (ACSM) provides similar recommendations: to achieve a minimum of 30 min of moderate-intensity physical activity five times per week or 20 min of vigorous-intensity three times per week [58].
While useful in all building types, stairs can be most effective for homes for the ageing populations where neurogenesis may be at a greater risk of decline. Multi-storey homes are considered beneficial for older adults who retire, suggesting that a multi-storey house can be a more suitable choice than a bungalow [59]. For instance, when bringing coffee, grabbing a snack, moving from a pantry to a kitchen or from a kitchen to a dining area, collecting laundry, moving objects from one room to another, or performing daily chores, staircases can help increase BDNF multiple times throughout the day. On another hand, homebodies who have poorer cognitive function and higher risk of depressive and anxiety symptoms [60,61] arguably can likely benefit from using stairs.
At the workplace, we show that stair use requires an active and non-brief use of stairs. Even though stair climbing in the form of exercise snacking is preferred over HIIT-based stair use among employees [62], and while exercise snacking itself has health benefits [63,64,65,66,67], we doubt that brief intermittent bouts (1 min each) per day can sufficiently boost BDNF unless future research provides evidence. We hypothesise that people at work may need to use the stairs for at least 6 min continuously, and in special cases, to potentially estimate a significant increase in BDNF. Still, future research can explore whether single intermittent stair use bouts (exercise snacking) can also increase BDNF levels, which are expected to remain at a low intensity.
In hospitals and educational buildings, there are tailored opportunities for brain-boosting building use through stair use, combined with walking in some cases, whereas commercial building uses may not benefit significantly from space utilisation due to frequent stops and the use of escalators instead of stairs. The Brain Booster Buildings framework supports efforts to encourage the use of stairs by NHS staff [68,69] and healthy hospital visitors [70], while also promoting the motivation of students to use stairs in university buildings [71,72].
In a common modern culture that often skips the stairs for the elevator or escalator, when one has the physical ability to use the stairs, it becomes a trade-off and an opportunity to boost essential molecules needed for the brain to thrive. Architects, policymakers, and researchers can greatly benefit from the framework established in this paper. Stair use should no longer be in the case of emergencies. Stair use can be a lifestyle prescription given to many as a cost-free option by policymakers, and architects can have an active role in making it an effective and appealing experience [73,74,75,76]. Future research should consider the interdisciplinary nature of this framework. We urge future researchers to conduct further experiments that can explain the nuanced differences in BDNF outcomes and help provide more tailored brain-boosting building use prescriptions in the future. Future research can quantify stair-specific dose–response relationships for BDNF across different ages and health profiles and test the parametric effects of geometry and layout in occupied buildings.

7. Conclusions

This paper presents novel scenario modelling using the Brain Booster Buildings framework established early in this paper. It emphasises that stair use represents a daily, cost-free opportunity for nurturing the human brain. The framework synthesises established MET values for stair climbing with BDNF responses observed in comparable-intensity walking and cycling studies. Based on these extrapolations, stair use is estimated to increase BDNF from as little as 6 min in buildings with more than three stories, or within 20 min of moderate intensity in buildings with fewer than three stories. This paper highlights that architects have a responsibility to design stair use experiences that are both effective in boosting BDNF and appealing to building users. This is especially important, given that arguably 90% of our time is spent indoors. The Brain Booster Buildings framework positions multi-storey buildings and high-rise architecture as accessible, cost-free infrastructure. Every voluntary physical activity becomes an opportunity for neurosustainability.

Author Contributions

Conceptualisation, M.H.K.; methodology, M.H.K.; validation, M.H.K. and K.S.; writing—original draft preparation, M.H.K.; writing—review and editing, M.H.K. and K.S.; visualisation, M.H.K.; supervision, K.S.; project administration, M.H.K. All authors have read and agreed to the published version of the manuscript.

Funding

This research received no external funding.

Data Availability Statement

The original contributions presented in this study are included in the article. Further inquiries can be directed to the corresponding author.

Acknowledgments

Special thanks to the support of Cambridge Commonwealth, European & International Trust, and the Jameel Education Foundation for funding the doctoral thesis of M.H.K. and for offering research funds that covered the open access publication fees for this article.

Conflicts of Interest

The authors declare no conflicts of interest.

References

  1. Martinowich, K.; Lu, B. Interaction between BDNF and serotonin: Role in mood disorders. Neuropsychopharmacology 2008, 33, 73–83. [Google Scholar] [CrossRef] [PubMed]
  2. Polyakova, M.; Stuke, K.; Schuemberg, K.; Mueller, K.; Schoenknecht, P.; Schroeter, M.L. BDNF as a biomarker for successful treatment of mood disorders: A systematic & quantitative meta-analysis. J. Affect. Disord. 2015, 174, 432–440. [Google Scholar] [CrossRef] [PubMed]
  3. Jin, Y.; Sun, L.H.; Yang, W.; Cui, R.J.; Xu, S.B. The role of BDNF in the neuroimmune axis regulation of mood disorders. Front. Neurol. 2019, 10, 515. [Google Scholar] [CrossRef] [PubMed]
  4. Taliaz, D.; Loya, A.; Gersner, R.; Haramati, S.; Chen, A.; Zangen, A. Resilience to chronic stress is mediated by hippocampal brain-derived neurotrophic factor. J. Neurosci. 2011, 31, 4475–4483. [Google Scholar] [CrossRef]
  5. Leschik, J.; Gentile, A.; Cicek, C.; Péron, S.; Tevosian, M.; Beer, A.; Radyushkin, K.; Bludau, A.; Ebner, K.; Neumann, I.; et al. Brain-derived neurotrophic factor expression in serotonergic neurons improves stress resilience and promotes adult hippocampal neurogenesis. Prog. Neurobiol. 2022, 217, 102333. [Google Scholar] [CrossRef]
  6. Ihara, K.; Yoshida, H.; Jones, P.B.; Hashizume, M.; Suzuki, Y.; Ishijima, H.; Kim, H.K.; Suzuki, T.; Hachisu, M. Serum BDNF levels before and after the development of mood disorders: A case–control study in a population cohort. Transl. Psychiatry 2016, 6, e782. [Google Scholar] [CrossRef]
  7. Bekinschtein, P.; Oomen, C.A.; Saksida, L.M.; Bussey, T.J. Effects of environmental enrichment and voluntary exercise on neurogenesis, learning and memory, and pattern separation: BDNF as a critical variable? In Seminars in Cell & Developmental Biology; Academic Press: Cambridge, MA, USA, 2011; Volume 22, pp. 536–542. [Google Scholar]
  8. Li, Y.; Li, F.; Qin, D.; Chen, H.; Wang, J.; Wang, J.; Song, S.; Wang, C.; Wang, Y.; Liu, S.; et al. The role of brain derived neurotrophic factor in central nervous system. Front. Aging Neurosci. 2022, 14, 986443. [Google Scholar] [CrossRef]
  9. Chen, S.-D.; Wu, C.-L.; Hwang, W.-C.; Yang, D.-I. More insight into BDNF against neurodegeneration: Anti-apoptosis, anti-oxidation, and suppression of autophagy. Int. J. Mol. Sci. 2017, 18, 545. [Google Scholar] [CrossRef]
  10. Sahay, A.; Scobie, K.N.; Hill, A.S.; O’Carroll, C.M.; Kheirbek, M.A.; Burghardt, N.S.; Fenton, A.A.; Dranovsky, A.; Hen, R. Increasing adult hippocampal neurogenesis is sufficient to improve pattern separation. Nature 2011, 472, 466–470. [Google Scholar] [CrossRef]
  11. Toda, T.; Parylak, S.L.; Linker, S.B.; Gage, F.H. The role of adult hippocampal neurogenesis in brain health and disease. Mol. Psychiatry 2019, 24, 67–87. [Google Scholar] [CrossRef]
  12. Azevedo, K.P.M.d.; de Oliveira, V.H.; Medeiros, G.C.B.S.d.; Mata, Á.N.d.S.; García, D.Á.; Martínez, D.G.; Leitão, J.C.; Knackfuss, M.I.; Piuvezam, G. The effects of exercise on BDNF levels in adolescents: A systematic review with meta-analysis. Int. J. Environ. Res. Public Health 2020, 17, 6056. [Google Scholar] [CrossRef]
  13. Fernández-Rodríguez, R.; Alvarez-Bueno, C.; Martínez-Ortega, I.A.; Martínez-Vizcaíno, V.; Mesas, A.E.; Notario-Pacheco, B. Immediate effect of high-intensity exercise on brain-derived neurotrophic factor in healthy young adults: A systematic review and meta-analysis. J. Sport Health Sci. 2022, 11, 367–375. [Google Scholar] [CrossRef]
  14. Khalil, M.H. The Impact of Walking on BDNF as a Biomarker of Neuroplasticity: A Systematic Review. Brain Sci. 2025, 15, 254. [Google Scholar] [CrossRef]
  15. Feter, N.; Alt, R.; Dias, M.G.; Rombaldi, A.J. How do different physical exercise parameters modulate brain-derived neurotrophic factor in healthy and non-healthy adults? A systematic review, meta-analysis and meta-regression. Sci. Sports 2019, 34, 293–304. [Google Scholar] [CrossRef]
  16. Khalil, M.H. The BDNF-interactive model for sustainable hippocampal neurogenesis in humans: Synergistic effects of environmentally-mediated physical activity, cognitive stimulation, and mindfulness. Int. J. Mol. Sci. 2024, 25, 12924. [Google Scholar] [CrossRef]
  17. Liu, P.Z.; Nusslock, R. Exercise-mediated neurogenesis in the hippocampus via BDNF. Front. Neurosci. 2018, 12, 52. [Google Scholar] [CrossRef] [PubMed]
  18. Rossi, C.; Angelucci, A.; Costantin, L.; Braschi, C.; Mazzantini, M.; Babbini, F.; Fabbri, M.E.; Tessarollo, L.; Maffei, L.; Berardi, N.; et al. Brain-derived neurotrophic factor (BDNF) is required for the enhancement of hippocampal neurogenesis following environmental enrichment. Eur. J. Neurosci. 2006, 24, 1850–1856. [Google Scholar] [CrossRef] [PubMed]
  19. Ribeiro, D.; Petrigna, L.; Pereira, F.C.; Muscella, A.; Bianco, A.; Tavares, P. The impact of physical exercise on the circulating levels of BDNF and NT 4/5: A review. Int. J. Mol. Sci. 2021, 22, 8814. [Google Scholar] [CrossRef]
  20. Moreno-Jiménez, E.P.; Flor-García, M.; Terreros-Roncal, J.; Rábano, A.; Cafini, F.; Pallas-Bazarra, N.; Ávila, J.; Llorens-Martín, M. Adult hippocampal neurogenesis is abundant in neurologically healthy subjects and drops sharply in patients with Alzheimer’s disease. Nat. Med. 2019, 25, 554–560. [Google Scholar] [CrossRef] [PubMed]
  21. Moreno-Jiménez, E.P.; Terreros-Roncal, J.; Flor-García, M.; Rábano, A.; Llorens-Martín, M. Evidences for adult hippocampal neurogenesis in humans. J. Neurosci. 2021, 41, 2541–2553. [Google Scholar] [CrossRef]
  22. Tobin, M.K.; Musaraca, K.; Disouky, A.; Shetti, A.; Bheri, A.; Honer, W.G.; Kim, N.; Dawe, R.J.; Bennett, D.A.; Arfanakis, K.; et al. Human hippocampal neurogenesis persists in aged adults and Alzheimer’s disease patients. Cell Stem Cell 2019, 24, 974–982. [Google Scholar] [CrossRef]
  23. Boldrini, M.; Fulmore, C.A.; Tartt, A.N.; Simeon, L.R.; Pavlova, I.; Poposka, V.; Rosoklija, G.B.; Stankov, A.; Arango, V.; Dwork, A.J.; et al. Human hippocampal neurogenesis persists throughout aging. Cell Stem Cell 2018, 22, 589–599. [Google Scholar] [CrossRef]
  24. Spalding, K.L.; Bergmann, O.; Alkass, K.; Bernard, S.; Salehpour, M.; Huttner, H.B.; Boström, E.; Westerlund, I.; Vial, C.; Buchholz, B.A.; et al. Dynamics of hippocampal neurogenesis in adult humans. Cell 2013, 153, 1219–1227. [Google Scholar] [CrossRef]
  25. Herrmann, S.D.; Willis, E.A.; Ainsworth, B.E.; Barreira, T.V.; Hastert, M.; Kracht, C.L.; Schuna, J.M.; Cai, Z.; Quan, M.; Tudor-Locke, C.; et al. 2024 Adult Compendium of Physical Activities: A third update of the energy costs of human activities. J. Sport Health Sci. 2024, 13, 6–12. [Google Scholar] [CrossRef] [PubMed]
  26. Khalil, M.H. Urban physical activity for neurogenesis: Infrastructure limitations. Front. Public Health 2025, 13, 1638934. [Google Scholar] [CrossRef] [PubMed]
  27. Bos, I.; Jacobs, L.; Nawrot, T.; de Geus, B.; Torfs, R.; Panis, L.I.; Degraeuwe, B.; Meeusen, R. No exercise-induced increase in serum BDNF after cycling near a major traffic road. Neurosci. Lett. 2011, 500, 129–132. [Google Scholar] [CrossRef]
  28. Klepeis, N.E.; Nelson, W.C.; Ott, W.R.; Robinson, J.P.; Tsang, A.M.; Switzer, P.; Behar, J.V.; Hern, S.C.; Engelmann, W.H. The National Human Activity Pattern Survey (NHAPS): A resource for assessing exposure to environmental pollutants. J. Expo. Sci. Environ. Epidemiol. 2001, 11, 231–252. [Google Scholar] [CrossRef]
  29. Sharkey, P. Homebound: The long-term rise in time spent at home among US adults. Sociol. Sci. 2024, 11, 553–578. [Google Scholar] [CrossRef]
  30. Shi, H.; Goulias, K.G. Long-term effects of COVID-19 on time allocation, travel behavior, and shopping habits in the United States. J. Transp. Health 2024, 34, 101730. [Google Scholar] [CrossRef]
  31. Morris, E.A.; Speroni, S.; Taylor, B.D. Going nowhere faster: Did the COVID-19 pandemic accelerate the trend toward staying home? J. Am. Plan. Assoc. 2025, 91, 361–379. [Google Scholar] [CrossRef]
  32. Khalil, M.H. Environmental affordance for physical activity, neurosustainability, and brain health: Quantifying the built environment’s ability to sustain BDNF release by reaching metabolic equivalents (METs). Brain Sci. 2024, 14, 1133. [Google Scholar] [CrossRef]
  33. Park, S.A.; Lee, A.Y.; Park, H.G.; Lee, W.L. Benefits of gardening activities for cognitive function according to measurement of brain nerve growth factor levels. Int. J. Environ. Res. Public Health 2019, 16, 760. [Google Scholar] [CrossRef]
  34. Willis, E.A.; Herrmann, S.D.; Hastert, M.; Kracht, C.L.; Barreira, T.V.; Schuna, J.M.; Cai, Z.; Quan, M.; Conger, S.A.; Brown, W.J.; et al. Older Adult Compendium of Physical Activities: Energy costs of human activities in adults aged 60 and older. J. Sport Health Sci. 2024, 13, 13–17. [Google Scholar] [CrossRef]
  35. Bull, F.C.; Al-Ansari, S.S.; Biddle, S.; Borodulin, K.; Buman, M.P.; Cardon, G.; Chaput, J.-P.; Chastin, S.; Chou, R.; Dempsey, P.C.; et al. World Health Organization 2020 guidelines on physical activity and sedentary behaviour. Br. J. Sports Med. 2020, 54, 1451–1462. [Google Scholar] [CrossRef] [PubMed]
  36. Teh, K.C.; Aziz, A.R. Heart rate, oxygen uptake, and energy cost of ascending and descending the stairs. Med. Sci. Sports Exerc. 2002, 34, 695–699. [Google Scholar]
  37. Cho, K.H.; Song, W.; Kim, J.; Jung, E.J.; Jang, J.; Im, S.H.; Kim, M. Energy expenditures for activities of daily living in Korean young adults: A preliminary study. Ann. Rehabil. Med. 2016, 40, 725–733. [Google Scholar] [CrossRef] [PubMed]
  38. Al Kandari, J.R.; Mohammad, S.; Al-Hashem, R.; Telahoun, G.; Barac-Nieto, M. Practical use of stairs to assess fitness, prescribe and perform physical activity training. Health 2016, 8, 1402–1410. [Google Scholar] [CrossRef]
  39. Yue, A.S.; Woo, J.; Ip, K.W.; Sum, C.M.; Kwok, T.; Hui, S.S. Effect of age and gender on energy expenditure in common activities of daily living in a Chinese population. Disabil. Rehabil. 2007, 29, 91–96. [Google Scholar] [CrossRef]
  40. Norton, K.; Norton, L.; Sadgrove, D. Position statement on physical activity and exercise intensity terminology. J. Sci. Med. Sport 2010, 13, 496–502. [Google Scholar] [CrossRef]
  41. Ramos, J.S.; Dalleck, L.C.; Tjonna, A.E.; Beetham, K.S.; Coombes, J.S. The impact of high-intensity interval training versus moderate-intensity continuous training on vascular function: A systematic review and meta-analysis. Sports Med. 2015, 45, 679–692. [Google Scholar] [CrossRef] [PubMed]
  42. Hutchinson, K.A.; Mohammad, S.; Garneau, L.; McInnis, K.; Aguer, C.; Adamo, K.B. Examination of the myokine response in pregnant and non-pregnant women following an acute bout of moderate-intensity walking. Front. Physiol. 2019, 10, 1188. [Google Scholar] [CrossRef]
  43. Kettinen, J.; Tikkanen, H.; Hiltunen, M.; Murray, A.; Horn, N.; Taylor, W.R.; Venojärvi, M. Cognitive and biomarker responses in healthy older adults to a 18-hole golf round and different walking types: A randomised cross-over study. BMJ Open Sport Exerc. Med. 2023, 9, e001629. [Google Scholar] [CrossRef] [PubMed]
  44. Yasuoka, Y.; Nakamura, T.; Umemoto, Y.; Kinoshita, T.; Hoekstra, S.P.; Hoshiai, K.; Ohko, H.; Abo, M.; Tajima, F. An 18-hole round of golf acutely elevates serum Interleukin-6 and brain-derived neurotrophic factor concentration-a pilot study. J. Phys. Fit. Sports Med. 2022, 11, 1–7. [Google Scholar] [CrossRef]
  45. Weston, K.S.; Wisløff, U.; Coombes, J.S. High-intensity interval training in patients with lifestyle-induced cardiometabolic disease: A systematic review and meta-analysis. Br. J. Sports Med. 2014, 48, 1227–1234. [Google Scholar] [CrossRef]
  46. Buchheit, M.; Laursen, P.B. High-intensity interval training, solutions to the programming puzzle: Part I: Cardiopulmonary emphasis. Sports Med. 2013, 43, 313–338. [Google Scholar] [CrossRef]
  47. Lasso-Quilindo, C.A.; Chalapud-Narvaez, L.M.; Garcia-Chaves, D.C.; Cristi-Montero, C.; Yañez-Sepulveda, R. Effect of 4 Weeks of High-Intensity Interval Training (HIIT) on VO2max, Anaerobic Power, and Specific Performance in Cyclists with Cerebral Palsy. J. Funct. Morphol. Kinesiol. 2025, 10, 102. [Google Scholar] [CrossRef] [PubMed]
  48. Gibbons, T.D.; Cotter, J.D.; Ainslie, P.N.; Abraham, W.C.; Mockett, B.G.; Campbell, H.A.; Jones, E.M.W.; Jenkins, E.J.; Thomas, K.N. Fasting for 20 h does not affect exercise-induced increases in circulating BDNF in humans. J. Physiol. 2023, 601, 2121–2137. [Google Scholar] [CrossRef]
  49. Li, Q.; Zhang, L.; Zhang, Z.; Wang, Y.; Zuo, C.; Bo, S. A shorter-bout of HIIT is more effective to promote serum BDNF and VEGF-A levels and improve cognitive function in healthy young men. Front. Physiol. 2022, 13, 898603. [Google Scholar] [CrossRef]
  50. Marquez, C.M.S.; Vanaudenaerde, B.; Troosters, T.; Wenderoth, N. High-intensity interval training evokes larger serum BDNF levels compared with intense continuous exercise. J. Appl. Physiol. 2015, 119, 1363–1373. [Google Scholar] [CrossRef]
  51. Goulet, N.; McCormick, J.J.; King, K.E.; Notley, S.R.; Goldfield, G.S.; Fujii, N.; Amano, T.; Kenny, G.P. Elevations in serum brain-derived neurotrophic factor following occupational heat stress are not influenced by age or common chronic disease. Temperature 2023, 10, 454–464. [Google Scholar] [CrossRef]
  52. Li, Y.; Liu, J.; Quan, M.; Zhuang, J.; Cao, Z.-B.; Zhu, Z.; Li, Y.; Herrmann, S.D.; Ainsworth, B.E. Energy costs of household and eldercare activities in young to middle-aged Chinese adults. J. Phys. Act. Health 2022, 19, 404–408. [Google Scholar] [CrossRef] [PubMed]
  53. Michael, E.; White, M.J.; Eves, F.F. Home-based stair climbing as an intervention for disease risk in adult females; a controlled study. Int. J. Environ. Res. Public Health 2021, 18, 603. [Google Scholar] [CrossRef] [PubMed]
  54. Sanchez-Lastra, M.A.; Ding, D.; Dalene, K.E.; del Pozo Cruz, B.; Ekelund, U.; Tarp, J. Stair climbing and mortality: A prospective cohort study from the UK Biobank. J. Cachexia Sarcopenia Muscle 2021, 12, 298–307. [Google Scholar] [CrossRef]
  55. Song, Z.; Wan, L.; Wang, W.; Li, Y.; Zhao, Y.; Zhuang, Z.; Dong, X.; Xiao, W.; Huang, N.; Xu, M.; et al. Daily stair climbing, disease susceptibility, and risk of atherosclerotic cardiovascular disease: A prospective cohort study. Atherosclerosis 2023, 386, 117300. [Google Scholar] [CrossRef]
  56. British Heart Foundation. Staying Active. Available online: https://www.bhf.org.uk/informationsupport/support/healthy-living/staying-active#:~:text=It’s%20recommended%20that%20you%20do,when%20running%2C%20swimming%20or%20cycling (accessed on 9 June 2025).
  57. National Health Service. Physical Activity Guidelines for Adults Aged 19 to 64. 2024. Available online: https://www.nhs.uk/live-well/exercise/physical-activity-guidelines-for-adults-aged-19-to-64/#:~:text=In%20general%2C%2075%20minutes%20of,running (accessed on 9 June 2025).
  58. American College of Sports Medicine. ACSM’s Guidelines for Exercise Testing and Prescription, 12th ed.; Lippincott Williams & Wilkins: Philadelphia, PA, USA, 2025. [Google Scholar]
  59. Baker, N.; Steemers, K. Healthy Homes: Designing with Light and Air for Sustainability and Wellbeing; Riba Publishing: London, UK, 2019. [Google Scholar]
  60. Khalil, M.H.; Steemers, K. Housing environmental enrichment, lifestyles, and public health indicators of neurogenesis in humans: A pilot study. Int. J. Environ. Res. Public Health 2024, 21, 1553. [Google Scholar] [CrossRef]
  61. McCormick, B.P.; Brusilovskiy, E.; Snethen, G.; Klein, L.; Townley, G.; Salzer, M.S. Getting out of the house: The relationship of venturing into the community and neurocognition among adults with serious mental illness. Psychiatr. Rehabil. J. 2022, 45, 18. [Google Scholar] [CrossRef]
  62. Stork, M.J.; Marcotte-Chénard, A.; Jung, M.E.; Little, J.P. Exercise in the workplace: Examining the receptivity of practical and time-efficient stair-climbing “exercise snacks”. Appl. Physiol. Nutr. Metab. 2023, 49, 30–40. [Google Scholar] [CrossRef] [PubMed]
  63. Weston, K.L.; Little, J.P.; Weston, M.; McCreary, S.; Kitchin, V.; Gill, A.; Niven, A.; McNarry, M.A.; Mackintosh, K.A. Application of exercise snacks across youth, adult and clinical populations: A scoping review. Sports Med.-Open 2025, 11, 27. [Google Scholar] [CrossRef]
  64. Islam, H.; Gibala, M.J.; Little, J.P. Exercise snacks: A novel strategy to improve cardiometabolic health. Exerc. Sport Sci. Rev. 2022, 50, 31–37. [Google Scholar] [CrossRef]
  65. Jones, M.D.; Clifford, B.K.; Stamatakis, E.; Gibbs, M.T. Exercise snacks and other forms of intermittent physical activity for improving health in adults and older adults: A scoping review of epidemiological, experimental and qualitative studies. Sports Med. 2024, 54, 813–835. [Google Scholar] [CrossRef]
  66. Yin, M.; Zheng, H.; Bai, M.; Huang, G.; Chen, Z.; Deng, S.; Lyu, M.; Deng, J.; Zhang, B.; Li, H.; et al. Effects of Integrating Stair Climbing-Based Exercise Snacks Into the Campus on Feasibility, Perceived Efficacy, and Participation Perspectives in Inactive Young Adults: A Randomized Mixed-Methods Pilot Study. Scand. J. Med. Sci. Sports 2024, 34, e14771. [Google Scholar] [CrossRef]
  67. Jenkins, E.M.; Nairn, L.N.; Skelly, L.E.; Little, J.P.; Gibala, M.J. Do stair climbing exercise “snacks” improve cardiorespiratory fitness? Appl. Physiol. Nutr. Metab. 2019, 44, 681–684. [Google Scholar] [CrossRef] [PubMed]
  68. Blake, H.; Lee, S.; Stanton, T.; Gorely, T. Workplace intervention to promote stair-use in an NHS setting. Int. J. Workplace Health Manag. 2008, 1, 162–175. [Google Scholar] [CrossRef]
  69. Jude, E.B.; Purohit, A.; Puri, S.; Heald, A.H.; Tentolouris, N. Stairway to health: Stair vs. elevator usage and its impact on the health of NHS Staff. J. Public Health 2025, 1–6. [Google Scholar] [CrossRef]
  70. Tzikas, A.; Koulierakis, G.; Athanasakis, K.; Merakou, K. Nudging Hospital Visitors Towards Stair Use, in Greece. J. Prev. 2025, 46, 189–199. [Google Scholar] [CrossRef]
  71. Bachert, P.; Hildebrand, C.; Erley, N.; Jekauc, D.; Wäsche, H.; Kunkel, J.; Woll, A. Students on stairs: A participatory approach using decisional cues in the form of motivational signs to promote stair use. J. Am. Coll. Health 2022, 70, 2152–2158. [Google Scholar] [CrossRef]
  72. Berardi, V.; Rosenberg, B.D.; Srivastava, S.; Estrada-Rand, N.; Frederick, J. Stair versus elevator use in a university residence hall setting. J. Am. Coll. Health 2023, 71, 997–1002. [Google Scholar] [CrossRef]
  73. Jennings, C.A.; Yun, L.; Loitz, C.C.; Lee, E.Y.; Mummery, W.K. A systematic review of interventions to increase stair use. Am. J. Prev. Med. 2017, 52, 106–114. [Google Scholar] [CrossRef] [PubMed]
  74. Mustafa, F.A.; Ali, J.S. Active Design: Architectural Interventions for Improving Occupational Health Through Reducing Sedentary Behavior-A Systematic Review. Am. J. Health Promot. 2023, 37, 93–102. [Google Scholar] [CrossRef] [PubMed]
  75. Crozier, A.J. Step up: Exploring the impact of social prompts on stair use in a university setting. Psychol. Sport Exerc. 2019, 41, 99–106. [Google Scholar] [CrossRef]
  76. Caputo, E.L.; Feter, N.; Alt, R.; da Silva, M.C. How do different interventions impact stair climbing? A systematic review and meta-analysis. Glob. Health Promot. 2022, 29, 74–82. [Google Scholar] [CrossRef] [PubMed]
Figure 1. A conceptual framework for boosting brain-derived neurotrophic factor (BDNF) through the use of stairs in buildings. Illustrated by Mohamed Hesham Khalil.
Figure 1. A conceptual framework for boosting brain-derived neurotrophic factor (BDNF) through the use of stairs in buildings. Illustrated by Mohamed Hesham Khalil.
Buildings 15 03730 g001
Figure 5. A conceptual illustration of how stair-use can increase BDNF in a 2-storey building without a walkable space. Estimated at 3 ± 0.3 m floor height.
Figure 5. A conceptual illustration of how stair-use can increase BDNF in a 2-storey building without a walkable space. Estimated at 3 ± 0.3 m floor height.
Buildings 15 03730 g005
Figure 6. A conceptual estimate of stair use duration respective to the number of floors to predict a significant change in BDNF levels. Estimated based on a 3 ± 0.3 m floor height.
Figure 6. A conceptual estimate of stair use duration respective to the number of floors to predict a significant change in BDNF levels. Estimated based on a 3 ± 0.3 m floor height.
Buildings 15 03730 g006
Table 3. Estimated BDNF increase through stair-use-based voluntary physical activity; estimated based on a 3 ± 0.3 m floor height and young adult subjects.
Table 3. Estimated BDNF increase through stair-use-based voluntary physical activity; estimated based on a 3 ± 0.3 m floor height and young adult subjects.
Stair-Use Activity TypeStair-Use DurationNumber of Floors for the Stair-Use Activity TypeEstimated BDNF Δ (in Blood Serum) *
MICE≥20 minContinuously ascend and descend 1–3 floors while performing daily chores.~+1000 to 1700 pg/mL (20 min)
HIIT6–20 minAscend < 3 stories while carrying loads (e.g., boxes, bags) or ≥ 3 floors without carrying, descend load-free, and repeat.~+900 pg/mL (6 min)
~+3900 to 5370 pg/mL (20 min)
* BDNF estimations are extrapolated from walking and cycling studies at comparable intensities.
Table 4. Modelled scenarios of brain-boosting stair use in residential buildings. Estimated based on 3 ± 0.3 m floor height and young adult subjects.
Table 4. Modelled scenarios of brain-boosting stair use in residential buildings. Estimated based on 3 ± 0.3 m floor height and young adult subjects.
Residential BuildingSpatial Activity Pattern ExampleDuration and ComponentsActivity TypeBrain Boosting Opportunity
1 floor (e.g., Bungalow)Walking within home.Light intensityRisk factor if relying on the building to boost BDNF. No vertical structure + limited horizontal space.
2 floors (e.g., ground + basement)Performing laundry or daily chores: 10 trips up/down stairs over 20 min while sorting, loading, and folding clothes, or cleaning the house.≥20 min stairs use (continuous while performing activities).MICEBasement stairs provide minimal but sufficient vertical infrastructure to use when combined with daily activities.
3 floors (e.g., townhouse, standalone)(a) Morning routine: bedroom (3rd) → kitchen (2nd) → garage (1st) repeated during chores, meal preparation.
(b) Carrying groceries or boxes upstairs.
(a) ≥20 min stairs use (continuous while performing activities).
(b) 6 min stairs use while carrying loads.
(a) MICE
(b) HIIT
Natural circulation integrates the stairs-based BDNF-boosting activity into daily routines.
>3 floors (apartment building)Taking groceries/packages from the lobby to a high-floor apartment, 2–3 trips.6 min stair use while carrying loads.HIITHigh capacity but elevator competition reduces actual use.
Table 5. Modelled scenarios of brain-boosting stair use in office buildings. Estimated based on 3 ± 0.3 m floor height and young adult subjects.
Table 5. Modelled scenarios of brain-boosting stair use in office buildings. Estimated based on 3 ± 0.3 m floor height and young adult subjects.
Office BuildingSpatial Activity Pattern ExampleDuration and ComponentsActivity TypeBrain Boosting Opportunity
1 floorWalking to printer, break room, colleague’s desk, restroom, parking lot.Light intensityThe 1-storey office layout allows movement but intensity is too low.
3 floors(a) Employee stairs for meetings: 1st floor office → 3rd floor conference → 2nd floor colleague, 3–4 times/day.
(b) Carrying boxes/packages upstairs.
(a) —
(b) 6 min stair use while carrying loads
(a) Light intensity
(b) HIIT
(a) Exercise snacking (single intermittent bouts) are brief and unlikely to reach a moderate intensity threshold.
(b) Some staff can benefit from stair use if their job description includes carrying packages, etc.
>3 floors(a,b) Stairs from 1st to 6th floor for bringing coffee, downstairs to bring papers, upstairs for a meeting.
(c) Carrying packages upstairs.
(a) ≥20 min if intermittent
(b) 6 min (cont.)
(c) 6 min
(a) MICE
(b,c) HIIT
Each ascent can be a sufficient brain booster but strong elevator preference limits use.
Table 6. Modelled scenarios of brain-boosting stair use in educational buildings. Estimated based on 3 ± 0.3 m floor height and young adult subjects.
Table 6. Modelled scenarios of brain-boosting stair use in educational buildings. Estimated based on 3 ± 0.3 m floor height and young adult subjects.
Educational BuildingSpatial Activity Pattern ExampleDuration and ComponentsActivity TypeBrain Boosting Opportunity
1 floor (e.g., elementary school)Walking between classroom, cafeteria, gym, library; outdoor movement between buildings.Light-to-moderate intensityExtensive walking space but insufficient intensity; outdoor opportunities available. Outdoor physical activity can be compensatory.
3 floors (e.g., middle and high schools)Class changes: 2nd floor classroom → 3rd floor lab → 1st floor cafeteria, walking hallways.≥20 minMICE (walking + stairs)Instructed circulation can create BDNF-boosting opportunities.
>3 floors (e.g., university buildings)(a) Ground floor lecture → 6th floor seminar, walking hallways to the classroom.6 minHIIT (ascent + either walking or descent)Students often carry backbacks that can increase the intensity.
Table 7. Modelled scenarios of brain-boosting stair use in hospital buildings. Estimated based on 3 ± 0.3 m floor height and young adult subjects.
Table 7. Modelled scenarios of brain-boosting stair use in hospital buildings. Estimated based on 3 ± 0.3 m floor height and young adult subjects.
Hospital BuildingSpatial Activity Pattern ExampleDuration and ComponentsActivity TypeBrain Boosting Opportunity
1 floor (e.g., outpatient clinic)Nurse walking between exam rooms, supply closet, reception, lab throughout shift.Light intensitySubstantial movement opportunity but insufficient intensity for BDNF elevation.
≥3 floors (e.g., community hospital, medical centre)(a) Healthcare worker: e.g., medication room (2nd) → patient rooms (3rd) → supply (1st), walking very long corridors.
(b) Medical staff carrying medical equipment upstairs, pushing a wheelchair patient, trolley or stretcher.
(a) ≥20 min (cont.)
(b) 6–20 min
(a) low or MICE
(b) MICE or HIIT
(a) Healthcare workers naturally accumulate movement; stairs add intensity, but the non-continuous use prevents reaching a MICE or HIIT type.
(b) Some medical staff can reach a MICE or HIIT activity if they carry medical equipment upstairs or push a wheelchair patient, trolley or stretcher.
Table 8. Modelled scenarios of brain-boosting stair use in commercial buildings. Estimated based on 3 ± 0.3 m floor height and young adult subjects.
Table 8. Modelled scenarios of brain-boosting stair use in commercial buildings. Estimated based on 3 ± 0.3 m floor height and young adult subjects.
Commercial BuildingSpatial Activity Pattern ExampleDuration and ComponentsActivity TypeBrain Boosting Opportunity
1, 3 or >3 floorsShoppers browse stores across a large footprint.Light-to-moderate intensityExtensive walking space available, but browsing shops and using escalators reduce the activity intensity.
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.

Share and Cite

MDPI and ACS Style

Khalil, M.H.; Steemers, K. Brain Booster Buildings: Modelling Stairs’ Use as a Daily Booster of Brain-Derived Neurotrophic Factor. Buildings 2025, 15, 3730. https://doi.org/10.3390/buildings15203730

AMA Style

Khalil MH, Steemers K. Brain Booster Buildings: Modelling Stairs’ Use as a Daily Booster of Brain-Derived Neurotrophic Factor. Buildings. 2025; 15(20):3730. https://doi.org/10.3390/buildings15203730

Chicago/Turabian Style

Khalil, Mohamed Hesham, and Koen Steemers. 2025. "Brain Booster Buildings: Modelling Stairs’ Use as a Daily Booster of Brain-Derived Neurotrophic Factor" Buildings 15, no. 20: 3730. https://doi.org/10.3390/buildings15203730

APA Style

Khalil, M. H., & Steemers, K. (2025). Brain Booster Buildings: Modelling Stairs’ Use as a Daily Booster of Brain-Derived Neurotrophic Factor. Buildings, 15(20), 3730. https://doi.org/10.3390/buildings15203730

Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.

Article Metrics

Back to TopTop