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Obesity occurs when energy intake exceeds energy expenditure. Humans expend energy through purposeful exercise and through changes in posture and movement that are associated with the routines of daily life [called nonexercise activity thermogenesis (NEAT)]. To examine NEAT's role in obesity, we recruited 10 lean and 10 mildly obese sedentary volunteers and measured their body postures and movements every half-second for 10 days. Obese individuals were seated, on average, 2 hours longer per day than lean individuals. Posture allocation did not change when the obese individuals lost weight or when lean individuals gained weight, suggesting that it is biologically determined. If obese individuals adopted the NEAT-enhanced behaviors of their lean counterparts, they might expend an additional 350 calories (kcal) per day.
(A) Time allocation for different postures for 10 obese and 10 lean sedentary subjects. Data are shown as mean þ SEM. Significant differences between lean and obese are indicated: *, P 0 0.001; **, P 0 0.0005. There were no statistically significant differences between females (n 0 10) and males (n 0 10): Females stood 470 T 35 min/day and males stood 429 T 40 min/day. (B) Relationship between total body movement and body fat content. Body fat, determined from dual x-ray absorptiometry, is expressed as a percentage (left) and mass (right) plotted against the total 10-day accelerometer output [accelerometer units (AU)] for 20 (10 obese and 10 lean) sedentary subjects. The open diamonds are data for females and the filled diamonds are data for males. There was no significant relationship between fat-free mass and accelerometer output (fig. S1). The relationship between NEAT by doubly labeled water adjusted by weight versus accelerometer output is shown in fig. S2. (C) (Left) Total daily energy expenditure and (right) NEAT in 10 obese and 10 lean sedentary subjects. The uppermost segments of the bars for obese individuals (vertical arrows) represent the additional energy that could be expended if these subjects were ambulatory for the same amount of time as lean subjects. BMR, basal metabolic rate; TEF, thermic effect of food. There was no significant difference in sleeping time between the lean group (423 T 15 min) and the obese group (434 T 17 min). The energy expenditure data and standard deviations appear in table S2. The relationship between NEAT measured with doubly labeled water and NEAT measured with the instruments is shown in fig. S3.
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References and Notes
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tive Grant no. 162-11-09. We would like to thank K.
Jones, I. Hora
´
cek, I. Mackie, C. Mainstone, F. Catzeflis,
N. Czaplewski, G. Morgan, Tin Nwe, N. Crumpler,
A. Roca, and R. Stanyon for samples, technical sup-
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Supporting Online Material
www.sciencemag.org/cgi/content/full/307/5709/580/
DC1
Materials and Methods
Figs. S1 to S3
Tables S1 to S7
References and Notes
10 September 2004; accepted 24 November 2004
10.1126/science.1105113
Interindividual Variation in
Posture Allocation: Possible Role
in Human Obesity
James A. Levine,
*
Lorraine M. Lanningham-Foster,
Shelly K. McCrady, Alisa C. Krizan, Leslie R. Olson, Paul H. Kane,
Michael D. Jensen, Matthew M. Clark
Obesity occurs when energy intake exceeds energy expenditure. Humans
expend energy through purposeful exercise and through changes in posture
and movement that are associated with the routines of daily life [called non-
exercise activity thermogenesis (NEAT)]. To examine NEAT’s role in obesity,
we recruited 10 lean and 10 mildly obese sedentary volunteers and measured
their body postures and movements every half-second for 10 days. Obese
individuals were seated, on average, 2 hours longer per day than lean
individuals. Posture allocation did not change when the obese individuals lost
weight or when lean individuals gained weight, suggesting that it is
biologically determined. If obese individuals adopted the NEAT-enhanced
behaviors of their lean counterparts, they might expend an additional 350
calories (kcal) per day.
Obesity is epidemic in high-income countries.
In the United States alone poor diet and
physical inactivity are associated with 400,000
deaths per year (1) and obesity-related medical
expenditures in 2003 approximated $75 billion
(2).Obesityisalsoanemergingproblemin
middle- and low-income countries, where the
health and fiscal costs are likely to be dev-
astating (3).
As the impact of obesity on health
escalates, so too does the need to understand
its pathogenesis. Weight gain and obesity
occur when energy intake exceeds energy
expenditure. We are interested in a specific
component of energy expenditure called
NEAT and the role it might play in human
obesity. NEAT is distinct from purposeful
exercise and includes the energy expenditure
of daily activities such as sitting, standing,
walking, and talking.
We have previously shown that when
humans overeat, activation of NEAT helps to
prevent weight gain (4). To better understand
NEAT and its role in obesity, we separated
NEAT into the thermogenesis associated with
posture (standing, sitting, and lying) and that
associated with movement (ambulation).
To investigate whether the obese state has
an effect on NEAT, we first developed and
validated a sensitive and reliable technology
for measuring the postural allocation of
NEAT in human volunteers (5, 6). This
physical activity monitoring system uses
inclinometers and triaxial accelerometers to
capture data on body position and motion
120 times each minute. By combining these
measurements with laboratory measures of
energy expenditure, we can summate NEAT
and define its components (7).
To compare body posture and body
motion in lean and obese people, we re-
cruited 20 healthy volunteers who were self-
proclaimed Bcouch potatoes.[ Ten participants
(five females and five males) were lean Ebody
mass index (BMI) 23 T 2 kg/m
2
^ and 10
participants (five females and five males)
were mildly obese (BMI 33 T 2kg/m
2
)(8)
(table S1). We deliberately selected mildly
obese subjects who were not incapacitated
by their obesity and who had no joint
problems or other medical complications
of obesity. The volunteers agreed to have all
of their movements measured for 10 days
andtohavetheirtotalNEATmeasuredwith
the use of a stable isotope technique (9).
They were instructed to continue their usual
daily activities and occupations and not
to adopt new exercise practices. Over the
10-day period, we collected È25 million
data points on posture and movement for
each volunteer.
Our analysis revealed that obese partic-
ipants were seated for 164 min longer per
day than were lean participants (Fig. 1A).
Correspondingly, lean participants were
upright for 152 min longer per day than
obese participants. Sleep times (lying) were
almost identical between the groups. Total
Endocrine Research Unit, Mayo Clinic, Rochester, MN
55905, USA.
*To whom correspondence should be addressed.
E-mail: Jim@Mayo.edu
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28 JANUARY 2005 VOL 307 SCIENCE www.sciencemag.org
584
body movement, 89% of which was ambu-
lation, was negatively correlated with fat
mass (Fig. 1, B and C). Notably, if the obese
subjects had the same posture allocation as
the lean subjects, they would have expended
an additional 352 T 65 (TSD) (range, 269 to
477) calories (kcal) per day (Fig. 1C).
To investigate whether these differences
in posture allocation are a cause or conse-
quence of obesity, we asked seven of the
original obese volunteers (four females and
three males, BMI 33 T 2 kg/m
2
) to undergo
supervised weight loss over a period of 8
weeks. The average weight loss was 8 kg.
Likewise, we recruited nine of the original
lean volunteers and one additional lean
volunteer (six females and four males, BMI
23 T 2 kg/m
2
) to undergo supervised over-
feeding over a period of 8 weeks. The av-
erage weight gain was 4 kg. After these
weight perturbations, we studied posture
allocation in these subjects for another 10
days. Interestingly, both the obese subjects
losing weight and the lean subjects gaining
weight maintained their original posture
allocation (Fig. 2). Thus, it appears that
interindividual differences in posture alloca-
tion are biologically determined.
It should be emphasized that this was a
pilot study and that the results need to be
confirmed in larger studies. Nevertheless, the
current data may be important for under-
Fig. 1. (A) Time allocation for different postures for
10 obese and 10 lean sedentary subjects. Data are
shown as mean þ SEM. Significant differences
between lean and obese are indicated: *, P 0 0.001;
**, P 0 0.0005. There were no statistically significant
differences between females (n 0 10) and males (n 0
10): Females stood 470 T 35 min/day and males
stood 429 T 40 min/day. (B)Relationshipbetween
total body movement and body fat content. Body
fat, determined from dual x-ray absorptiometry, is
expressed as a percentage (left) and mass (right)
plotted against the total 10-day accelerometer
output [accelerometer units (AU)] for 20 (10 obese
and 10 lean) sedentary subjects. The open diamonds
are data for females and the filled diamonds are data for males. There was
no significant relationship between fat-free mass and accelerometer
output (fig. S1). The relationship between NEAT by doubly labeled water
adjusted by weight versus accelerometer output is shown in fig. S2. (C)
(Left) Total daily energy expenditure and (right) NEAT in 10 obese and 10
lean sedentary subjects. The uppermost segments of the bars for obese
individuals (vertical arrows) represent the additional energy that could be
expended if these subjects were ambulatory for the same amount of time
as lean subjects. BMR, basal metabolic rate; TEF, thermic effect of food.
There was no significant difference in sleeping time between the lean
group (423 T 15 min) and the obese group (434 T 17 min). The energy
expenditure data and standard deviations appear in table S2. The rela-
tionship between NEAT measured with doubly labeled water and NEAT
measured with the instruments is shown in fig. S3.
Fig. 2. (A) Posture allocation in seven obese sedentary subjects who underwent caloric restriction
(8). (Left) Posture allocation data at baseline and after weight loss of 8 T 2 kg. (Right) The time the
subjects spent standing/ambulating at baseline is plotted against the time the subjects spent
standing/ambulating after weight loss. (B) Posture allocation in 10 lean sedentary subjects who
underwent experimental weight gain (8). (Left) The posture allocation data for baseline and after
weight gain of 4 T 2 kg. (Right) The time the subjects spent standing/ambulating at baseline is
plotted against the time the subjects spent standing/ambulating after weight gain. Data are shown
as mean þ SEM.
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www.sciencemag.org SCIENCE VOL 307 28 JANUARY 2005
585
standing the biology of obesity and how best
to treat it. The propensity of obese persons to
sit more than lean individuals has several
potential explanations. Rodent studies sup-
port the concept that there are central and
humoral mediators of NEAT (10, 11). For
example, we have shown that a neuropeptide
associated with arousal, orexin (12), in-
creases NEAT in rats when injected into
the paraventricular nucleus (PVN) of the
hypothalamus. Preliminary data suggest that
PVN injections of orexin also cause dose-
dependent increases in standing posture
allocation in rats (13). Thus, there may be
central and humoral mediators that drive the
sedentary behavior of obese individuals. The
negative relationship between fat mass and
movement (Fig. 1B) raises the intriguing
possibility that body fat releases a factor that
slows physical activity in obesity. However,
these data also demonstrate that posture
allocation is not the mechanism by which
NEAT is modulated with short-term over-
feeding. One hypothesis is that this occurs
through modulation of energy efficiency;
this is an area worthy of future investigation.
These data may also have implications
for obesity intervention. One could argue
that obese individuals have a biologically
determined posture allocation and therefore
are destined to become obese. If this were
true, obesity would have been as common 50
years ago as it is today. However, obesity
rates have increased and continue to do so
(14). We speculate that obese and lean
individuals respond differently to the envi-
ronmental cues that promote sedentary be-
havior. If the obese volunteers adopted the
NEAT-enhanced behavior of their lean
counterparts, they could expend an addition-
al 350 kcal per day. Over a year, this alone
could result in a weight loss of È15 kg, if
energy intake remained unchanged. Herein
lies the rationale behind nationwide ap-
proaches to promote NEAT in small incre-
ments (15). For example, in Rochester,
Minnesota, in 1920 before car use was com-
monplace the average walk to and from work
was 1.6 miles (16). If walking this distance
to work were reinstituted by our obese
subjects, all of whom currently drive to
work, an extra 150 kcal per day could be
expended. We will need to use similar
measures to promote NEAT as an impetus
to create an active and dynamic environment
in which, for example, dancing supersedes
television as a leisure activity. Approaches
that succeed in getting people out of their
chairs and moving could have substantial
impact on the obesity epidemic.
References and Notes
1.A.H.Mokdad,J.S.Marks,D.F.Stroup,J.L.
Gerberding, JAMA 291, 1238 (2004).
2. E. A. Finkelstein, I. C. Fiebelkorn, G. Wang, Obes. Res.
12, 18 (2004).
3. World Health Organization, Obesity: Preventing and
Managing the Global Epidemic (Geneva, Switzerland,
1997).
4. J. A. Levine, N. L. Eberhardt, M. D. Jensen, Science
283, 212 (1999).
5. J. A. Levine, P. A. Baukol, K. R. Westerterp, Med. Sci.
Sports Exerc. 33, 1593 (2001).
6. J. A. Levine, E. L. Melanson, K. R. Westerterp, J. O.
Hill, Eur. J. Clin. Nutr. 57, 1176 (2003).
7. J. A. Levine, E. L. Melanson, K. R. Westerterp, J. O. Hill,
Am. J. Physiol. Endocrinol. Metab. 281, E670 (2001).
8. Materials and methods are available as supporting
material on Science Online.
9. D. A. Schoeller, C. A. Leitch, C. Brown, Am. J. Physiol.
251, R1137 (1986).
10. J. A. Levine, J. Nygren, K. R. Short, K. S. Nair, J. Appl.
Physiol. 94, 165 (2003).
11. K. Kiwaki, C. M. Kotz, C. Wang, L. Lanningham-Foster,
J. A. Levine, Am. J. Physiol. 286, E551 (2004).
12. J. G. Sutcliffe, L. de Lecea, Nature Med. 10, 673
(2004).
13. C. M. Kotz, personal communication.
14. J. O. Hill, H. R. Wyatt, G. W. Reed, J. C. Peters,
Science 299, 853 (2003).
15. More information about promoting NEAT in small
increments can be found at www.smallstep.gov and
www.americaonthemove.org.
16. L. Lanningham-Foster, L. J. Nysse, J. A. Levine, Obes.
Res. 11, 1178 (2003).
17. We thank the volunteers, dietitians, food technicians,
nursing staff, and the Mass Spectrometer Core at the
General Clinical Research Center, A. Oberg for
assistance with statistics, and P. Baukol for techni-
cal support. Supported by NIH grants DK56650,
DK63226, DK66270, and M01 RR00585, by T. S. and
D. B. Ward, and by the Mayo Foundation.
Supporting Online Material
www.sciencemag.org/cgi/content/full/307/5709/584/
DC1
Materials and Methods
Figs. S1 to S4
Tables S1 and S2
References
20 October 2004; accepted 7 December 2004
10.1126/science.1106561
Sequence-Directed DNA
Translocation by Purified FtsK
Paul J. Pease,
1
*
Oren Levy,
2
*
Gregory J. Cost,
1
Jeff Gore,
3
Jerod L. Ptacin,
1
David Sherratt,
5
Carlos Bustamante,
1,3,4
.
Nicholas R. Cozzarelli
1,2
.
DNA translocases are molecular motors that move rapidly along DNA using
adenosine triphosphate as the source of energy. We directly observed the
movement of purified FtsK, an Escherichia coli translocase, on single DNA
molecules. The protein moves at 5 kilobases per second and against forces up
to 60 piconewtons, and locally reverses direction without dissociation. On
three natural substrates, independent of its initial binding position, FtsK
efficiently translocates over long distances to the terminal region of the
E. coli chromosome, as it does in vivo. Our results imply that FtsK is a
bidirectional motor that changes direction in response to short, asymmetric
directing DNA sequences.
DNA translocases are adenosine triphosphate
(ATP)–driven machines required for DNA
replication, recombination, and transfer
within and between cells (1–6). FtsK is a
membrane-bound and septum-localized E.
coli translocase that coordinates cell division
with chromosome segregation (7). At times,
the product of chromosome replication is a
circular dimer rather than two monomers.
These dimers are resolved by the XerCD
site-specific recombinase at a site near the
terminus of replication, termed dif (8).
Recombination between the distant dif sites
requires FtsK. In addition, at the time of cell
division some DNA may remain in the septal
region, and FtsK appears to act as a pump to
clear this region of DNA (9, 10). FtsK may
also promote disentanglement of chromo-
some termini by means of an interaction with
topoisomerase IV (11).
Translocases move along DNA or move
the DNA if the translocase is anchored. In
either case, translocases must be able to move
in a specific direction relative to the DNA.
Translocase directionality could be determined
by strand polarity for single-strand tracking
enzymes, nonrandom orientation of trans-
locase binding through localized accessory
factors or binding sites, or DNA sequences
that affect the enzyme during translocation. In
E. coli, provocative genetic experiments
showed that lambda-phage DNA inserted
near dif disrupted chromosome dimer reso-
lution in a manner dependent on insertion
orientation (9). Thus, DNA sequences could
be directing FtsK toward dif so that it can
activate XerCD recombination.
1
Department of Molecular and Cell Biology,
2
Biophysics
Graduate Group,
3
Department of Physics,
4
Howard
Hughes Medical Institute, University of California,
Berkeley, CA 94720–3204, USA.
5
Division of Molecular
Genetics, Department of Biochemistry, University of
Oxford, OX1 3QU, UK.
*These authors contributed equally to this paper.
.To whom correspondence should be addressed.
E-mail: ncozzare@socrates.berkeley.edu (N.R.C.);
carlos@alice.berkeley.edu (C.B.)
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... 44 Dzięki temu wspomniani absolwenci lepiej adaptują się do wymogów życia społecznego: łatwiej znajdują pracę, posiadają wyższy status społeczny, wiodą bardziej aktywne i niezależne życie w dorosłości. 45 Prof. Bartkowski podkreśla, że po ukończeniu szkoły młode osoby z niepełnosprawnością w większości przypadków nie znajdują pracy, przede wszystkim z powodu swoich kwalifikacji. W ten sposób uruchamia się proces trwałej dezaktywizacji zawodowej. ...
... Przyrost tkanki tłuszczowej a zmiany aktywności NEAT po 8 tygodniach podawania pokarmu przekraczającego zapotrzebowanie kaloryczne o 1000 kcal dziennie u 16 szczupłych ochotników prowadzących siedzący tryb życia (28). (B) Specjalna bielizna z czujnikami pozycji i aktywności (45). (C) Czas trwania poszczególnych komponentów aktywności NEAT u 10 osób szczupłych i 10 otyłych prowadzących siedzący tryb życia podczas diety na utrzymanie wagi (45). ...
... (B) Specjalna bielizna z czujnikami pozycji i aktywności (45). (C) Czas trwania poszczególnych komponentów aktywności NEAT u 10 osób szczupłych i 10 otyłych prowadzących siedzący tryb życia podczas diety na utrzymanie wagi (45). (D) Czas trwania poszczególnych komponentów aktywności NEAT u osób szczupłych przed i po wzroście masy ciała oraz u osób otyłych przed i po spadku masy ciała (45). ...
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Full-text available
Analiza stanu istniejącego oraz określenie naukowych i praktycznych przesłanek proponowanych scenariuszy zmian w zakresie planowanych przestrzeni do nauki w szkołach podstawowych w zakresie wyposażenia pomieszczeń w meble wspierające rozwój kompetencji proinnowacyjnych u uczniów, w tym ułatwiające pełniejsze włączenie uczniów z różnego rodzaju dysfunkcjami (fizycznymi, neurologicznymi) w proces nauczania wspomnianych kompetencji. Analiza przygotowana przez Instytut Wzornictwa Przemysłowego Sp. z o.o. dla Ministerstwa Przedsiębiorczości i Technologii. Podsumowanie Współczesna rola szkoły jako instytucji kształcącej kreatywność i postawy proinnowacyjne uczniów winna być rozumiana w kontekście holistycznego podejścia do zdrowia człowieka zgodnie z definicją zdrowia Światowej Organizacji Zdrowia. Rolą szkoły jest wspieranie osiągnięcia przez ucznia teraz i w przyszłości pełnego dobrostanu fizycznego, umysłowego i społecznego, w tym samorealizacji własnych, osobistych celów, dążeń i planów w kontekście celów, dążeń i planów społeczności, w której żyje. Zdrowie fizyczne winno być rozumiane w dużej części jako podstawa, bez której wszelkie działania w sferze psychicznej, intelektualnej czy emocjonalnej tracą na efektywności. Na lata szkolne przypada czas najbardziej dynamicznego rozwoju fizycznego, a przebieg tego procesu w dużym stopniu determinuje zdrowie osobnicze: obecne i przyszłe. Projektując wyposażenie współczesnej szkoły oraz planując działania programowe w zakresie edukacji proinnowacyjnej trzeba brać pod uwagę szereg zjawisk zachodzących w rozwijającym się organizmie oraz w grupach rówieśniczych, jakim są klasy rocznikowe uczniów. Najważniejsze z nich to: 1. Proces wzrastania przejawiający się zmianami wymiarów ciała i jego części; 2. Dynamika (tempo) wzrastania ciała i jego poszczególnych części i jej zmienność w czasie i w zależności od etapów rozwoju, powodująca zmiany proporcji ciała 3. Proces dojrzewania, w tym dojrzewania płciowego, wpływający na dynamikę wzrastania, przemiany fizjologiczne, ale także na procesy psychiczne; 4. Nieprawidłowości rozwojowe oraz czynniki ryzyka i okresy zwiększonej podatności na ich wystąpienie; 5. Procesy zachodzące na poziomie populacji, jak trend sekularny dzieci i młodzieży przejawiający się w postaci osiągania większych ostatecznych wymiarów ciała, akceleracji (przyspieszenia) rozwoju i dojrzewania oraz odwrócenie pewnych etapów rozwoju. Najważniejsze problemy dotyczące wyposażenia szkół związane z tym, że jest ono adresowane i użytkowane przez uczniów znajdujących się w okresie intensywnego wzrastania i dojrzewania dla którego charakterystyczne jest duże zróżnicowanie międzyosobnicze oraz dynamiczne zmiany zachodzące w czasie (uczeń rozpoczynający naukę we wrześniu, kończąc ją w czerwcu może być zupełnie innym człowiekiem pod względem fizycznym i psychicznym). Znajomość zaburzeń stanu zdrowia występujących u dzieci w wieku szkolnym ułatwia, ale i nakłada na szkołę obowiązek podejmowania działań profilaktycznych. Najczęstsze z zaburzeń to choroby układu ruchu o etiologii przeciążeniowej, jak bóle kręgosłupa, czy stany zapalne w obrębie dłoni i nadgarstka, skoliozy idiopatyczne oraz nadwaga i otyłość. Popularną "ławkę szkolną" należy rozpatrywać w kategorii stanowiska pracy i zgodnie z zasadami ergonomii, w oparciu o adaptowane wyniki badań biomechanicznych prowadzonych na osobach dorosłych, wykorzystać stanowiska umożliwiające pracę w różnych pozycjach: siedzącej, siedząco-stojącej czy siedząco leżącej. Kluczowe jest zapewnienie możliwości i promowanie częstych zmian pozycji pracy, zapobieganie hipokinezie i długotrwałemu pozostawaniu w wymuszonej, statycznej pozycji. Koncepcją mogącą wesprzeć dotychczasowe wysiłki mające na celu zahamowania epidemii nadwagi i otyłości u dzieci, która znakomicie się wpisuje w koncepcję szkoły nowego typu, jest zwiększenie wydatku energetycznego w postaci termogenezy nie związanej z ćwiczeniami (non-exercise activity thermogenesis, NEAT). Istniejące wymagania normatywne dotyczące stanowiska pracy ucznia i wyposażenia szkół są spójne z ideą szkoły wspomagającej rozwój kompetencji kreatywnych i umożliwiają co do zasady promocję zmian pozycji pracy, jak i projektowanie zróżnicowanych funkcjonalnie siedzisk i stołów. Brak jest natomiast uregulowań normatywnych dedykowanych dla dzieci i młodzieży dotyczących stanowiska pracy z monitorami ekranowymi stacjonarnymi i przenośnymi. Praktyka wskazuje, że dzieci pracują z komputerami w pozycjach nadmiernie obciążających układ ruchu, co może przyczyniać się do powstawania schorzeń i dolegliwości o etiologii przeciążeniowej. Problematyka pracy z urządzeniami cyfrowymi jest złożona ze względu na bardzo szybki rozwój technologii informatycznych i pojawianie się urządzeń i funkcji dotychczas nieistniejących, niemniej jednak problem w świetle współczesnej wiedzy o fizjologii i biomechanice człowieka jest poważny, narasta i nie może być pomijany. Podsumowując należy podkreślić, że koncepcja szkoły wspierającej rozwój kompetencji kreatywnych i postaw proinnowacyjnych, w której nauczanie oparte jest o tworzenie środowiska inspirującego spontaniczną aktywność własną uczniów, dynamicznie dostosowującego się do tematyki zajęć, sprzyja równocześnie zdrowiu i potrzebom przynależnym okresowi rozwoju fizycznego dziecka dzięki ograniczeniu długotrwałej hipokinezy, umożliwieniu dynamicznej zmiany pozycji pracy, zachęcaniu do spontanicznego ruchu i multisensorycznej stymulacji psychofizycznej. Sprzyja także integracji dzieci z różnego rodzaju niepełnosprawnościami lub znajdujących się w różnym fizjologicznym stadium rozwoju psychofizycznego, z uwagi na umożliwienie dostosowania środowiska pracy w aspekcie przestrzennym i funkcjonalnym do zróżnicowanych potrzeb. Projektowane wyposażenie, oprócz zapewnienia walorów ergonomicznych i prozdrowotnych powinno zapewnić możliwość pracy zespołowej, możliwość wyrażenia i prezentacji własnych pomysłów, odpowiedni poziom stymulacji za pomocą bodźców sensorycznych oraz otoczenie zapewniające poczucie bezpieczeństwa. Istotnym zagadnieniem jest koszt sprzętu, przy czym można wyróżnić dwa rodzaje podejścia: preferowanie wysokiej jakości produktów, o wysokiej trwałości, co oznacza także stosunkowo wysoką cenę lub preferowanie produktów tanich, świadomie nie zapewniających wieloletniej trwałości, z krótką gwarancją, które mogą być często wymieniane na nowe, zgodne z najaktualniejszymi trendami, dzięki czemu możliwe jest dynamiczne reagowanie na zmieniające się potrzeby użytkowników i nie ma potrzeby wieloletniego przechowywania nieużywanych sprzętów. W przypadku współczesnej szkoły opartej na paradygmacie nowoczesnego podejścia do nauczania, w którym wyposażenie szkoły jest narzędziem systemu nauczania można, po przeprowadzeniu analiz ekonomicznych, rozważyć koncepcję oferującą większą elastyczność w dostosowywaniu wyposażenia szkoły do szybko zachodzących w programach edukacyjnych i nadążaniu za przemianami cywilizacyjnymi. Projektowanie wyposażenia i wnętrz placówek edukacyjnych, aranżacja przestrzeni, wybór odpowiednich mebli i urządzeń jest zadaniem wymagającym szerokiej wiedzy z zakresu przebiegu i celu procesu pedagogicznego, auksologii (rozwoju fizycznego, psychicznego i ruchowego dzieci i młodzieży), zdrowia publicznego, biomechaniki, ergonomii, psychologii (w tym psychologii koloru), architektury wnętrz,, wzornictwa przemysłowego, technologii i wielu innych. Z uwagi na złożoność problemu celowe i wskazane jest powoływanie do tego typu zadań zespołów multidyscyplinarnych i oraz specjalistycznych zespołów doradczych.
... Almost anyone can identify with the discomfort of sitting for prolonged periods, feelings of being antsy, jittery, squirmy, restless and/or fidgety, and the relief provided by movement (Levine et al., 2005). Several slang terms are also associated with similar conditions and feelings, including being "cooped up, " "stir crazy, " or having "cabin fever." ...
... Nevertheless, the authors note that, "core affective valence may have a direct, immediate impact on behavior through behavioral urges" (Brand and Ekkekakis, 2018). The second problem is that this theory was created to explain the complex behaviors of exercise and regimented physical activities -as opposed to the greater spectrum of physically active behaviors, including spontaneous physical activity (Levine et al., 2005). The third issue is that the model represents sedentary behaviors as typically contrasting with physical activity; restraining forces pulling against propelling forces to alternate from one behavior to the other (e.g., flipping a single switch). ...
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To better explain daily fluctuations in physical activity and sedentary behavior, investigations of motivation are turning from social cognitive frameworks to those centered on affect, emotion and automaticity, such as the Affect and Health Behavior Framework (AHBF), Integrated Framework and Affective-Reflective Theory (ART). This shift has necessitated: (a) re-examination of older theories and their constructs, such as drives, needs and tensions and (b) an inspection of competing theories from other fields that also attempt to explain dynamic changes in health behaviors. The Dynamical Model of Desire, Elaborated Intrusion Theory and others commonly share with AHBF the idea that human behavior is driven strongly by desires and/or the similar concepts of wants, urges, and cravings. These affectively-charged motivation states (ACMS) change quickly and may better explain physical activity behavior from one moment to the next. Desires for movement predominantly derive from negative but also positive reinforcement. Data from clinical populations with movement dysfunction or psychiatric disorders provides further evidence of these drivers of movement. Those with Restless Legs Syndrome, akathisia, tic disorders and exercise dependence all report strong urges to move and relief when it is accomplished. Motor control research has identified centers of the brain responsible for wants and urges for muscular movement. Models elaborated herein differentiate between wants, desires, urges and cravings. The WANT model (Wants and Aversions for Neuromuscular Tasks) conceptualizes desires for movement and rest as varying by magnitude, approach or avoidance-orientation (wants versus aversions) and as occupying independent dimensions instead of opposite ends of the same axis. For instance, one hypothetically might be in a state of both high desire for movement and rest simultaneously. Variations in motivation states to move and rest may also be associated with various stress states, like freezing or fight and flight. The first validated instrument to measure feelings of desire/want for movement and rest, the CRAVE Frontiers in Psychology | www.frontiersin.org 1 November 2020 | Volume 11 | Article 568390 Stults-Kolehmainen et al. Desire, Urge and State Motivation Scale (Cravings for Rest and Volitional Energy Expenditure) is already shedding light on the nature of these states. With these advances in theory, conceptual modeling and instrumentation, future investigations may explore the effects of desires and urges for movement and sedentary behavior in earnest.
... As a case in point, older adults typically reduce their energy intake over time [16], primarily driven by a lack of hunger, which is termed "the anorexia of aging" [17]. Conversely, positive energy balance (energy intake exceeding expenditure), could potentially facilitate adiposity accumulation [18,19]. Furthermore, older adults consistently under-consume protein [17,20], and exhibit a higher saturated fatty acid to polyunsaturated fatty acid intake ratio, as well as a specific deficiency in omega-3 fatty acids like alpha-linolenic acid [16,20,21], with both dietary patterns strongly associated with cardiovascular disease mortality [22,23]. ...
... Interestingly, high self-reported standing time has been associated with a reduced risk of obesity in middle-aged women (55-65 years) [32]. Acutely displacing sedentary time in younger adults with standing marginally increases energy expenditure [18,33], suggesting that a reduced obesity risk with a high standing time may primarily be due to a reduced energy intake. Accordingly, sustained postural transition in rodents results in a reduced energy intake [34], which appears to be exclusively dependent on an osteocyte strain detection mechanism (termed "the gravitostat"), activated as an effector in response to increased loading through the lower limbs [35]. ...
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Displacing Sedentary Behaviour (SB) with light intensity physical activity (LIPA) is increasingly viewed as a viable means of health enhancement. It is, however, unclear whether any behavioural compensations accompany such an intervention. Therefore, the aim of this study was to identify any dietary changes that accompany SB displacement. We hypothesised that SB displacement would improve dietary quality. Thirty-five elderly females (73 ± 5 years) were randomly allocated to one of three groups: (1) sedentary behaviour fragmentation (SBF) (n = 14), (2) continuous LIPA (n = 14), or (3) control (n = 7). Habitual diet (four-day food diary) and physical behaviour (accelerometery) were assessed at weeks 0 and 8. Out of 45 nutrients examined, only glucose exhibited a group × time interaction (p = 0.03), mediated by an exclusive reduction following SBF (−31%). SBF was also the sole experimental group to increase nutrients promoting bone health (SBF: 17%, LIPA: −34%. control: 21%), whereas both experimental groups consumed more nutrients promoting anabolism (SBF: 13%, LIPA: 4%, control: −34%) (z-scores). New ambulators (n = 8) also consumed more nutrients promoting bone health (16%)/anabolism (2%) (z-scores), including significantly increased Zinc intake (p = 0.05, 29%). Displacing SB with LIPA improves dietary quality in older females. Furthermore, SB fragmentation appears advantageous for various dietary outcomes.
... Our data show reduced hip circumference following both interventions. Given that LIPA raises energy expenditure (Carter et al., 2015;Lerma et al., 2016), a chronically sustained LIPA increase likely created a negative energy balance (Levine et al., 2005), beneficially reducing what we will assume were fat deposits around the hips. Furthermore, AGR also exhibited a trend to decrease over time. ...
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Rationale: The COVID-19 pandemic is limiting outdoor and community-based activities, especially for older adults owing to the requirement for self-isolation, potentially increasing prolonged sedentary behavior (SB). Given a poor tolerance for intense exercise, SB displacement with light intensity physical activity (LIPA) is a promising health enhancing alternative. Therefore, the aims of this study were to investigate the effects of two different types of SB displacement on health outcomes in older adults and any differential impact of associated LIPA pattern. Method: 28 older women (age: 73 ± 5 years, height: 1.60 ± 0.07 m, weight: 67 ± 10 kg, and BMI: 26.1 ± 3.6 kg/m2) underwent overnight fasted dual energy x-ray absorptiometry (DEXA) imaging, blood sampling, and functional assessments before being randomly allocated to one of two groups: (1) single continuous bout of 45–50 min LIPA daily (n = 14); or (2) SB fragmentation (SBF; ~48 min LIPA daily, 2 min LIPA for every 30 min of SB; n = 14). Compliance was systematically monitored using tri-axial accelerometery. All measures were taken at weeks 0 and 8. Results: Physical behavior significantly altered (decreased SB/increased LIPA; p < 0.05) and to a similar extent in both groups. We observed a significant reduction in serum triglycerides [p = 0.045, effect size (ɳp2) = 0.15; SBF: −0.26 ± 0.77 mmol/L, LIPA: −0.26 ± 0.51 mmol/L], improved 30 s sit-to-stand (STS) count (p = 0.002, ɳp2 = 0.32, 2 ± 3 STS) and speed (p = 0.009, ɳp2 = 0.35, −10 ± 33%), as well as increased average handgrip strength (p = 0.001, ɳp2 = 0.45, 6 ± 12%), and gait speed (p = 0.005, ɳp2 = 0.27, 0.09 ± 0.16 m/s) in both groups. Interestingly, SBF caused a greater increase in peak handgrip strength (8 ± 14%), compared to LIPA (2 ± 10%; p = 0.04, ɳp2 = 0.38). Conclusion: SB displacement induced significant improvements in fasting triglycerides, gait speed, as-well as STS endurance/speed in older women. Frequent vs. continuous SB displacement also caused greater increases in handgrip strength. While both SB displacement protocols display promise as efficacious home-based interventions for self-isolating older adults, our results would suggest a physical functioning advantage of the SBF protocol for certain outcomes.
... Last but not least, some studies have suggested the association of obesity and overweight with sedentary behavior. 11,12 Sedentary behavior is known as sitting or lying down during waking hours and using very little energy-less than 1.5 times the metabolic rate. 13 In-patients with schizophrenia have more sitting time (around 2.3 h/day) compared to healthy controls with corresponding age, gender, and BMI. ...
Article
Purpose To assess the influence of lifestyle factors, antipsychotic medications, and psychosis symptoms on obesity in a group of male patients with schizophrenia in Lebanon. Design/Methods A cross‐sectional study conducted between May and July 2018 enrolling 149 male patients with chronic schizophrenia. Results We found that 59.1% of the patients were obese/overweight. Older age and higher negative and total positive and negative syndrome scale scores were significantly associated with lower body mass index values. Practice Implications This study shed light on some factors associated with obesity in male patients with schizophrenia, which may be targeted for the prevention and management of obesity. Some interventions were proposed such as focusing on patients' physical health, psychiatric treatment, and maintaining a healthy diet and a healthy lifestyle.
... El gasto energético de las actividades diarias como pararse, caminar, moverse de un lado a otro, son actividades que no son consideradas como ejercicio planeado en la vida diaria de una persona (Levine et al., 2005). El NEAT (Non-Exercise Activity Thermogenesis) es la representación de un movimiento espontáneo durante el día, ya que el movimiento ambulatorio, consiste en estar parado o caminando básicamente y representa mayor gasto de calorías por día, lo cual puede ayudar al control del peso. ...
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