Standing up for children's health and education: questioning the sedentary nature of classrooms

Professor Jo Salmon

Centre for Physical Activity & Nutrition Research

(C-PAN), Deakin University

The Biannual Fritz Duras Lecture,Dean’s Lecture Series, University of Melbourne

July 27, 2010

Overview

• Children’s health in Australia

• Sedentary behaviour (or time spent sitting): an alternative perspective

• Role of schools & teachers in reducing children’s sitting time

• As the pioneer of physical education in Australia & a former physician, Professor Fritz Duras (1896 – 1965) would have some interesting thoughts about current role of schools & education in children’s health in Australia

Boys Girls

2–3y 4–8 y 9–13 y 14–16y 2–3y 4–8y 9–13 y 14–16y

% Australian children overweight/obese, 2007

(CSIRO, 2008)

%

Childhood overweight/obesity: Worldwide trends & 2010 projections

%

Wang & Lobstein IJPO 2006

Trends in overweight/obesity among children in Australia: 1985-2005

Olds et al IJO 2010

Odds ratios for obesity in young adulthood

Whitaker et al, 1997

Obesity trends & Type 2 diabetes among children in Japan

Kitagawa T et al. Clin Pediatr 1998

Type 2 diabetes

Obesity

Typ

e 2

dia

bet

es i

nci

den

ce /

100

000

po

pu

lati

on

per

yea

r

8.0

7.0

6.0

5.0

4.0

3.0

2.0

1.0

8.0

7.0

6.0

5.0

19951995198519801975

Prevalen

ce of o

besity (%

)

Role of energy balance behaviours

Health behaviours present the

“greatest single domain of

influence” on health in the population

(McGinnis et al., Health Affairs, 2002)

Health

Genetics

Environ-ment

HealthBehavior

Medical care

Social

30%

5%15%

10% 40%

Physical activity

ChildhoodObesity & metabolic

health

Energy dense drinks & foods

Sedentary behaviour

Genetics

Sedentary behaviour (or time spent sitting): an alternative perspective

word sedentary derives from the Latin verb sedere, meaning to sit

a distinct group of sitting/lying behaviours that involve low energy expenditure to perform (≤1.8 METs)

EG: schoolwork, reading, watching TV, computer use, car travel

Changes in children’s discretionary and non-discretionary time

Change in electronic entertainment media environment

Median mins/day TV viewing 1949-2000

Marshall et al, 2006

Change in homework time 1981-1997, US

Hofferth & Sandberg, 2000

Hrs

/wee

k

Illustration of SB based on muscular activity

SITTING

4 STEPS GETTING OUTOF A CHAIR

STANDING

Hamilton et al Diabetes 2007

Screen-time & children’s health (Rey-López et al, 2008)

Objectively-assessed sedentary time & health(Sardinha et al Diab Care 2008)

Adj for sex, birth weight, pubertal status, fat mass

HOMA-IR by stratified quartiles of time spent sedentary (Actigraph), p<0.05 between Q1 & Q4 (n=147)

Patterns of sedentary time

0

1000

2000

3000

4000

5000

6000

TIME

AC

TIV

ITY

Mod-to-Vigorous PA

Sedentary (<100 counts per minute)

Light Intensity

Interruptions or breaks in sustained periods being sedentary

Acknowledgement: Genevieve Healy, UQ

Mean accumulated time spent sedentary across school day (Salmon, Healy, Hume, Ridley, Timperio, Dunstan, Owen, Crawford)

174±46 mins/day (48% of time)

51%48% (p<0.001)

SB & light PA : r = -0.78SB & MVPA: r = -0.55

mins

N=2,452 participants

Mean number sedentary breaks in school day

33±6 breaks/day10-12 yo = 34 breaks/day

5-6 yo = 31 breaks/day (p<0.001)

Breaks & light PA : r = 0.37Breaks & MVPA: r = -0.06

Associations with BMI z-score

Total sedentary time*

5-6 yo: r = -0.04 (ns)

10-12 yo: r = 0.01 (ns)

Sedentary breaks*

5-6 yo: r = -0.12 (p=0.001)

10-12 yo: r = -0.11 (p<0.001)

*partial correlations adj for light & MVPA

Sedentary breaks/day & weight status

p=0.01p=0.04

AOR (light, mvpa) for each additional break 5% less likely ov/ob

1PA defined > 3 METs (green line)SB defined as 1.0-1.8 METs (shaded area)

Hypothetical1 EE over a 12-hour day for 2 children - both meeting PA recommendations

How can we intervene to reduce children’s discretionary & non-discretionary sedentary time?

• What are the potential health & educational benefits?

“One boy’s day” ( Ackn: Barker & Wright, 1951)

Role of schools & teachers in reducing children’s sitting time & on educational outcomes

Strategies to reduce children’s TV viewing

Study settings Strategies Outcome

School-based Educational +++++++ -

Family-based Educational ++ 000 ~

Reinforcement/contingency ++

TV allowance unit ++++ ~

Computer software +

Active electronic games +

Primary-care Educational +00

TV allowance unit 0

Community/population Statewide campaign +

Educational 00

Lanningham-Foster et al. Changing the school environment to increase children’s PA Obesity 2008

3 conditions:

Traditional school

Activity permissive school

Standing classroom

Mahar et al Effects of a classroom-based program on physical activity and on-task behavior. MSSE 2006

Grieco et al. Physically active academic lessons, time on task & BMI. MSSE 2009.

Mean % of time on task for the inactive control condition (left) & the active condition (right) for normal weight, at risk & overweight children (n=97)

Liu et al Evaluation of a classroom-based physical activity promoting programme. Obes Rev 2008

10-min activity break every day during school class times

Hrs

/day

Erwin et al Promoting children’s health through physically active math classes. Health Promot Practice

Step rate (mean ± SE) during baseline and physical activity (PA) integration math classesStep rate (mean ± SE) during baseline and physical activity (PA) integration school days

Reed et al. Impact of active lessons on fluid intelligence & academic performance. JPAH 2010• PA integrated into core curricula (~30

mins/day, 3 days/wk, Jan-April 2008) n=155, 9yr olds

• Used non-invasive fluid intelligence cognitive measures & State-mandated academic achievement tests

• Children in active lessons performed better on Fluid Intelligence Test & on the Social Studies academic achievement test

Summary

• Active lessons can:– lead to increased PA across the school day– lead to increased time on task/concentration– lead to better fluid intelligence scores

• What about reducing overall sitting time in class?

• What about increasing number of interruptions/breaks to sitting in class?

• Not just school time important, family setting also key focus

Transform-Us! intervention for reducing sedentary behaviour & promoting physical activity

Salmon1, Hume1, Arundell1*, Brown1*, Hesketh1, Daly2, Dunstan3, Ball1, Crawford1, Pearson1, Cerin4, Moodie1, Bagley1*, Chin A Paw5

1Deakin Uni; 2Uni Melb; 3Baker/IDI; 4Hong Kong Uni; 5Vumc Netherlands; *PhD students

Aims

Examine efficacy of 18-mth intervention targeting reductions in SB & increases in PA alone & in combination among 8-9 yr olds compared with current practice

Examine health outcomes, mediators & perform economic evaluation

Participants & design

20 primary schools (within 50km Melbourne), ~600 children aged 8-9 yrs

All year 3 students in intervention schools will receive the intervention, those with active consent will participate in assessment

4 groups:SB-I reducing sedentary (sitting) time at school & home

PA-I increasing PA during school breaks & outside of school hours

SB+PA-I combination of above

C usual curriculum

Intervention strategies

SB-I PA-I SB+PA-ISchool environment- Curriculum

component18 key learning messages 18 key learning messages 18 key learning messages

- Class strategies Standing lessons (1/day)Active 2- min breaks after 30-min class time

- Standing lessonsActive breaks

- Physical environment

- Provision of sporting equipment and signage

Provision of sporting equipment and signage

Home environment- Homework (h/w)

tasks- Newsletters

Reduce sitting time while completing h/w Tips for reducing sitting time at home

h/w tasks incorporate PA Tips for increasing PA at home

h/w tasks incorporate PA and reductions in sitting timeTips to reduce sitting time and promote PA at home

SB-I: reduce sitting in class

Delivery of 9 key messages/yr

Teachers will modify the delivery of one class lesson per day (30-45 minutes) so children complete the lesson standing (eg, classroom activity stations)

On average, this will result in 150-mins less sitting per week

SB-I: interrupt sitting in class

Interrupt 90-120 min classroom teaching blocks every 30-mins with 2-min guided light-intensity activity break (eg, standing passing ball around while recalling key learning outcomes from current lesson)

Should equate to ~6 mins interrupted sitting time every 2 hrs (~ 60-minutes less sitting time per week)

SB-I: family setting

8 postcards/yr to parents with tips & key messages for reducing SB at home (eg, effective use of rules)

Homework assignments (eg, switch off TV for weekend)

TV allowance unit

PA-I: environmental cues & prompts

access to PA equipment (recess & lunch breaks)

Line markings

Signage

DID YOU KNOW IT TAKES 30 HOPS TO

GET TO THE LIBRARY FROM

HERE??

PA-I: key messages & active homework

Delivery of 9 key messages/yr

8 postcards/yr to parents with tips & key messages for encouraging child’s PA at home & in neighbourhood (eg, Kinect Australia website and free Infoline)

Active homework (eg, go for a walk in your street with mum or dad & count the number of letterboxes)

Yamax Digiwalker pedometer

Pilot study

2009, pilot study to test strategies to reduce children’s sitting time in class & at home

n=124 children, n=6 teachers, n=28 parents

Teachers delivered 2 standing lessons & interrupted sitting over 2-wks & gave 2 homework tasks designed to reduce sitting time & increase PA

Standing lessons

Talking easels

Standing homework

Walk around Australia

Interrupted sitting class time

Stand & Discuss

Interrupted sitting homework

Stand & spell/rise & read

Sedentary time in class (mins/day)*

*Actigraph accelerometer (sed time <100cpm)

Percent of time in sedentary, LPA, MVPA Weeks 1 & 3 during classtime

Week 1 Week 3

Children’s perceptions

“When you’re standing, you might fiddle with your legs, and you don’t hear what the teachers say” (Yr 4 child)

“I would like to do more standing lessons because if you sit down for too long you get all ‘blah’ and then you don’t focus as much” (Yr 4 child)

Teachers’ perceptions

“I try to get them …to move …around a bit and stuff, but to do stuff at the standing lesson …it was great fun, it was new for them, so they really enjoyed it.” (Yr 4 teacher)

“they (parents) loved the idea behind it, of getting kids …moving around in class a bit more” (Yr 4 teacher)

Study progress

July 2010, have parental consent for 589 children from 20 primary schools in Melbourne to participate in assessment components of intervention & 353 (60%) of these children have undergone a fasting blood sample test

PD with teachers commencing this week!

Reflection & future directions

Can have strong synergies between physical activity, health & education

Active lessons NOT intended to replace PE!!

Standing/active classrooms have previously been trialled (eg, Liu et al 2008; Lanningham-Foster et al

2008; Grieco et al 2009) effects on reduced sitting time & health are unknown

Interruptions to sustained periods of sitting at school & home untested

Focus on promoting PA, reducing SB or both?

Reductions in SB likely to result in increased light-intensity PA (unknown health implications)

Targeting discretionary & non-discretionary time more effective than targeting only one?

Organisational change & pedagogy in schools

Ideal child’s day would include much less sitting than is currently the case & would embed PA throughout the day

One boy’s day –Take 2!

Final word from Prof Duras:

• “So, rightly understood, the physician becomes somewhat of an educationist, and the teacher tries to treat his [or her] pupil with the understanding, the love and the patience of a good physician”

AcknowledgementsStarring: Jack, Henry & Helen Brown & Leo

the Golden Retriever as themselves!Cinematography: Peter Brown

Funding: National Health & Medical Research Council, National Heart Foundation of Australia and sanofi-aventis, Mazda Foundation

The Behavioural Epidemiology Team

David Dunstan, Neville Owen, Gen Healy & team

In memory: Leigh Brown

• Senior Lecturer, Medical Sciences, RMIT• Co-ordinated courses in the Bachelor of

Applied Science (Physical Education) & Bachelor of Applied Science (Human Movement) degrees

• Long history working with Sydney Swans FC