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Interindividual Variation in Posture Allocation: Possible Role in Human Obesity

February 2005
Science 307(5709):584-6

DOI: 10.1126/science.1106561

Source
PubMed

Authors:

James Levine

University of Bristol

Lorraine Lanningham-Foster

Iowa State University

Shelly K Mccrady

Mayo Foundation for Medical Education and Research

Alisa C Krizan

Show all 8 authorsHide

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.

…

(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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References and Notes

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Taxonomic and Geographic Reference,D.E.Wilson,

D. M. Reeder, Eds. (Johns Hopkins Univ. Press, Baltimore,

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32. The research was funded and supported by federal

funds from the National Cancer Institute, NIH, under

contract no. N01-CO-12400, and the Darwin Initia-

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-

port, and advice.

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

^ and 10

participants (five females and five males)

were mildly obese (BMI 33 T 2kg/m

)(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

) 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

) 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.

R EPORTS

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,

Oren Levy,

Gregory J. Cost,

Jeff Gore,

Jerod L. Ptacin,

David Sherratt,

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.

Department of Molecular and Cell Biology,

Biophysics

Graduate Group,

Department of Physics,

Howard

Hughes Medical Institute, University of California,

Berkeley, CA 94720–3204, USA.

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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Innowacyjne meble szkoły dla innowatora

Book

Full-text available

Sep 2018

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.

Motivation States for Physical Activity and Sedentary Behavior: Desire, Urge, Wanting, and Craving

Article

Full-text available

Nov 2020

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.

Displacing Sedentary Behaviour with Light Intensity Physical Activity Spontaneously Alters Habitual Macronutrient Intake and Enhances Dietary Quality in Older Females

Article

Full-text available

Aug 2020

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.

The Effects of Displacing Sedentary Behavior With Two Distinct Patterns of Light Activity on Health Outcomes in Older Adults (Implications for COVID-19 Quarantine)

Article

Full-text available

Dec 2020

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.

Factors associated with overweight and obesity in Lebanese male patients with schizophrenia

Article

Nov 2020
PERSPECT PSYCHIATR C

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.

Capítulo 8. Hábitos saludables que pueden prolongar la vida. Libro Bienestar y Salud Social.

Chapter

Full-text available

Aug 2020

Edna Judith Nava-González

Promover la modificación de hábitos de estilo de vida, son necesarios para beneficiarnos de sus efectos metabólicos positivos, incluida la reversión de riesgos cardiovasculares y enfermedades crónicas a futuro. La dificultad para lograr cambios drásticos en la alimentación y la actividad física, por ende el control del peso, el consumo moderado de alcohol y evitar fumar, son difíciles de mantenerlos a lago plazo, y es necesario llevar en- foques basados en cambios conservadores más fáciles de conseguir y mantener.

Sedentary Lifestyle: Overview of Updated Evidence of Potential Health Risks

Article

Nov 2020

One-third of the global population aged 15 years and older engages in insufficient physical activities, which affects health. However, the health risks posed by sedentary behaviors are not well known. The mean daily duration of sedentary behavior is 8.3 hours among the Korean population and 7.7 hours among the American adult population. Sedentary lifestyles are spreading worldwide because of a lack of available spaces for exercise, increased occupational sedentary behaviors such as office work, and the increased penetration of television and video devices. Consequently, the associated health problems are on the rise. A sedentary lifestyle affects the human body through various mechanisms. Sedentary behaviors reduce lipoprotein lipase activity, muscle glucose, protein transporter activities, impair lipid metabolism, and diminish carbohydrate metabolism. Furthermore, it decreases cardiac output and systemic blood flow while activating the sympathetic nervous system, ultimately reducing insulin sensitivity and vascular function. It also alters the insulin-like growth factor axis and the circulation levels of sex hormones, which elevates the incidence of hormone-related cancers. Increased sedentary time impairs the gravitostat, the body's weight homeostat, and weight gain, adiposity, and elevated chronic inflammation caused by sedentary behavior are risk factors for cancer. Sedentary behaviors have wide-ranging adverse impacts on the human body including increased all-cause mortality, cardiovascular disease mortality, cancer risk, and risks of metabolic disorders such as diabetes mellitus, hypertension, and dyslipidemia; musculoskeletal disorders such as arthralgia and osteoporosis; depression; and, cognitive impairment. Therefore, reducing sedentary behaviors and increasing physical activity are both important to promote public health.

"Active Consulting" During and Post COVID-19: Opportunities for Clinicians to Move More

Article

Full-text available

Oct 2020
Ir Med J

Exercise Therapy for the Overweight Adult

Chapter

Dec 2006

EGZERSİZ DIŞI AKTİVİTE TERMOJENEZİ VE OBEZİTE İLİŞKİSİ (The relationship between Non-Exercise Activity Thermogenesis (NEAT) and obesity)

Chapter

Full-text available

Sep 2020

Halil İbrahim Ceylan

Obesity and the Environment: Where Do We Go from Here?

Article

Full-text available

Mar 2003
Science

The obesity epidemic shows no signs of abating. There is an urgent need to push back against the environmental forces that are producing gradual weight gain in the population. Using data from national surveys, we estimate that affecting energy balance by 100 kilocalories per day (by a combination of reductions in energy intake and increases in physical activity) could prevent weight gain in most of the population. This can be achieved by small changes in behavior, such as 15 minutes per day of walking or eating a few less bites at each meal. Having a specific behavioral target for the prevention of weight gain may be key to arresting the obesity epidemic.

Tracmor system for measuring walking energy expenditure

Article

Full-text available

Oct 2003
EUR J CLIN NUTR

Walking is an important mode of exercise and is likely to represent a major component of nonexercise activity thermogenesis. The question arises, how best to quantify walking-energy expenditure (EE) in free-living individuals. The triaxial accelerometer for movement registration (Tracmor) is a valid measure of body displacement and so we wanted to evaluate this tool for quantifying walking-EE. In this study, we test the hypothesis that walking-EE, measured in a Room Calorimeter, can be predicted from Tracmor output using a regression equation derived from a brief Tracmor/treadmill/Metabolic Cart protocol. First, 11 healthy subjects completed a 40-min procedure whereby they wore a Tracmor unit and walked on a treadmill at 0, 1, 2 and 3 mph while EE was measured using a Metabolic Cart. This allowed a regression equation to be defined for each subject to convert Tracmor output to EE. Each subject then entered a Room Calorimeter wearing the Tracmor Unit and walked at two self-selected velocities ('slow', 'fast') while EE was measured. 'Tracmor/regression equation' predictions of walking-EE were compared with Room Calorimeter measurements of walking-EE for the two velocities. The 'Tracmor/regression equation' prediction of EE for walking slowly was 6.36+/-1.67 kJ/min, and for walking fast it was 11.0+/-2.60 kJ/min. Room Calorimeter measurements were 6.43+/-1.85 and 10.9+/-3.03 kJ/min, respectively. The intraclass correlation coefficient for slow-paced walking was 0.93 (P<0.001), and for fast-paced walking it was 0.82 (P<0.005). When combined with laboratory measures of EE, the Tracmor accelerometer provides useful data on walking-EE and is applicable to free-living individuals.

Mesozoic and early Cenozoic terrestrial ecosystems

Article

Jan 1992

16019

Classification of Mammals Above Species Level

Article

Jan 1997

Labor Saved, Calories Lost: The Energetic Impact of Domestic Labor-saving Devices

Article

Oct 2003
Obes Res

As the prevalence of obesity has increased, so has sedentariness. Progressive sedentariness has been attributed to greater use of labor saving devices, such as washing machines, and less nonexercise walking (e.g., walking to work). However, there is a paucity of data to support this conclusion. In this study, we address the hypothesis that domestic mechanization of daily tasks has resulted in less energy expenditure compared with performing the same tasks manually. Energy expenditure was measured in four groups of subjects (122 healthy adult men and women total) from Rochester, Minnesota. Energy expenditure was measured using indirect calorimetry while subjects performed structured tasks such as cleaning dishes and clothes, stair climbing, and work-associated transportation, and these values were compared with the respective mechanized activity. Energy expenditure was significantly greater and numerically substantial when daily domestic tasks were performed without the aid of machines or equipment (clothes washing: 45 +/- 14 vs. 27 +/- 9 kcal/d; dish washing: 80 +/- 28 vs. 54 +/- 19 kcal/d; transportation to work: 83 +/- 17 vs. 25 +/- 3 kcal/d; stair climbing: 11 +/- 7 vs. 3 +/- 1 kcal/d; p < 0.05). The combined impact of domestic mechanization was substantial and equaled 111 kcal/d. The magnitude of the energetic impact of the mechanized tasks we studied was sufficiently great to contribute to the positive energy balance associated with weight gain. Efforts focused on reversing sedentariness have the potential to impact obesity.

Obesity: Preventing and Managing the Global Epidemic: Report of a WHO

Article

Jan 2000

Doubly labeled water method: In vivo oxygen and hydrogen isotope fractionation

Article

Jan 1987
Am J Physiol

The accuracy and precision of the doubly labeled water method for measuring energy expenditure are influenced by isotope fractionation during evaporative water loss and CO2 excretion. To characterize in vivo isotope fractionation, we collected and isotopically analyzed physiological fluids and gases. Breath and transcutaneous water vapor were isotopically fractionated. The degree of fractionation indicated that the former was fractionated under equilibrium control at 37 degrees C, and the latter was kinetically fractionated. Sweat and urine were unfractionated. By use of isotopic balance models, the fraction of water lost via fractionating routes was estimated from the isotopic abundances of body water, local drinking water, and dietary solids. Fractionated water loss averaged 23% (SD = 10%) of water turnover, which agreed with our previous estimates based on metabolic rate, but there was a systematic difference between the results based on O2 and hydrogen. Corrections for isotopic fractionation of water lost in breath and (nonsweat) transcutaneous loss should be made when using labeled water to measure water turnover or CO2 production.

Validation of the Tracmor triaxial accelerometer system for walking

Article

Oct 2001
MED SCI SPORT EXER

Walking is likely to contribute substantially to nonexercise activity thermogenesis. The Tracmor triaxial accelerometer system (Maastricht, The Netherlands) is the most widely validated system for detecting body movement in free-living subjects. The aim of this study was to validate the Tracmor triaxial accelerometer system for estimating the energy expenditure of walking. Experiments were conducted in healthy subjects. First, baseline variability for Tracmor output was determined for subjects standing still. Second, Tracmor output was compared for walking on a treadmill and on level ground. Third, both Tracmor output and energy expenditure were compared for walking on a treadmill and walking on level ground. Finally, the effect of gradient on Tracmor output and energy expenditure was compared for subjects walking on a treadmill. The data demonstrated excellent reproducibility for comparing Tracmor output for standing (CV < 2%). There were excellent log-linear relationships between velocity and Tracmor output walking on a treadmill (r = 0.998) and on level ground (r = 0.999). Tracmor output and the energy expenditure of walking were inseparable for the two modalities of walking. However, the variance in response was such that to reliably derive the relationship between Tracmor output and energy expenditure, separate regression equations are needed for each subject. Finally, the Tracmor accelerometer did not detect the increased energy expenditure of walking that occurs as gradient increases. The Tracmor triaxial accelerometer provides reproducible and reliable data on the body motion associated with walking regardless of whether a subject walks on a treadmill or level ground. Tracmor units can be used to predict the energetic cost of walking provided that separate regression equations are derived for each subject to convert Tracmor output to energy expenditure.

Effect of hyperthyroidism on spontaneous physical activity and energy expenditure in rats

Article

Jan 2003
J APPL PHYSIOL

Thyroid hormone excess is associated with increased energy expenditure. The contributions of increases in spontaneous physical activity and nonexercise activity thermogenesis (NEAT) to this effect have not been defined. To address the hypothesis that hyperthyroidism is associated with increased spontaneous physical activity and NEAT, we rendered rats hyperthyroid by using continuous infusion of high-dose triiodothyronine for 14 days and measured the effects on physical activity and NEAT. On day 14, in the hyperthyroid group the mean +/- SD triiodothyronine concentration was 755 +/- 137 (range 574-919) ng/dl and in the control group 59 +/- 0.5 (58-59) ng/dl. Over the 14-day treatment period, mean spontaneous physical activity increased in the hyperthyroid rats from 24 +/- 7 to 36 +/- 6 activity units (AU)/min; P < 0.001 but did not increase in the controls (23 +/- 7 vs. 22 +/- 4 AU/min). Also, over the 14-day period, daily NEAT increased in the hyperthyroid rats from 8.1 +/- 2.8 to 19.7 +/- 5.0 kcal/day (P < 0.001) but did not increase in the controls (8.7 +/- 3.5 cf 9.4 +/- 1.7 kcal/day; not significant). In conclusion, hyperthyroidism is associated with increased spontaneous physical activity and NEAT.

Orexin A (hypocretin 1) injected into hypothalamic paraventricular nucleus and spontaneous activity in rats

Article

May 2004
AM J PHYSIOL-ENDOC M

In humans, nonexercise activity thermogenesis (NEAT) increases with positive energy balance. The mediator of the interaction between positive energy balance and physical activity is unknown. In this study, we address the hypothesis that orexin A acts in the hypothalamic paraventricular nucleus (PVN) to increase nonfeeding-associated physical activity. PVN-cannulated rats were injected with either orexin A or vehicle during the light and dark cycle. Spontaneous physical activity (SPA) was measured using arrays of infrared activity sensors and night vision videotaped recording (VTR). O(2) consumption and CO(2) production were measured by indirect calorimetry. Feeding behavior was assessed by VTR. Regardless of the time point of injection, orexin A (1 nmol) was associated with dramatic increases in SPA for 2 h after injection (orexin A: 6.27 +/- 1.95 x 10(3) beam break count, n = 24; vehicle: 1.85 +/- 1.13 x 10(3), n = 38). This increase in SPA was accompanied by compatible increase in O(2) consumption. Duration of feeding was increased only when orexin A was injected in the early light phase and accounted for only 3.5 +/- 2.5% of the increased physical activity. In a dose-response experiment, increases in SPA were correlated with dose of orexin A linearly up to 2 nmol. PVN injections of orexin receptor antagonist SB-334867 were associated with decreases in SPA and attenuated the effects of PVN-injected orexin A. Thus orexin A can act in PVN to increase nonfeeding-associated physical activity, suggesting that this neuropeptide might be a mediator of NEAT.