Presentation by Dr. Bob Ross at the Striking a Balance . . . Weigh in with Knowledge, Research, Practice - Symposium

1. Striking a Balance... Weigh in with Knowledge, Research,
Practice Symposium, Canadian Diabetes Association
Ottawa, September 30th, 2013.
The Other 23 1/2 Hours in the Day –
Beyond Physical Activity
Robert Ross
PhD, FACSM, FAHA
School of Kinesiology and Health Studies
Medicine, Division of Endocrinology and Metabolism
Queen’s University
Kingston, Ontario, Canada

2. No Conflicts of Interest to Declare

3. The Issue for today’s session
Sedentary living is real…
….but is it a Unique Public Health Problem?

4. Slide courtesy David Dunstan

5. Slide courtesy David Dunstan

6. Physical Activity
Sedentary

7. A Typical Canadian Day?
Slide courtesy David Dunstan

8. Accelerometer
‘Actigraph’

10. Physical Activity of Canadian Adults: Accelerometer Results
from the 2007-2009 Canadian Health Measures Survey
Colley et al Health Reports 22 (1) March 2011

11. Accelerometer Data for a Single Day
Moderate/vigorous-intensity Activity
Light-intensity Activity
Sedentary
Time of Day

12. Accelerometer Data for a Single Day
Moderate/vigorous-intensity Activity
95% of waking hours
Light-intensity Activity
Sedentary
Time of Day

13. The Other 23 1/2 Hours in the Day –
Beyond Physical Activity
Two Questions:
Is Sedentary time associated with
health outcomes?
Is Sedentary time associated with
health outcomes independent of
physical activity?

14. A 2-week reduction of ambulatory activity (walking) is associated with
a 17% reduction in Insulin sensitivity in 10 healthy young men.
Krogh-Madsen et al J Appl Physiol 108: 1034-1040, 2010.
Explored whether a decrease in daily steps from ~10,000 to 1,300 was
associated with a decrease in insulin sensitivity in young men.
17%

16. Key Point
2-hr glucose (mmol/l)
Sedentary
LPA
Sedentary time (A) by accelerometers was
detrimentally associated with 2-hr glucose
independent of moderate-to-vigorous-intensity
activity.
MVPA
Healy et al. Diabetes Care

17. Age-adjusted All-cause Mortality
Sitting time and Mortality from All Causes, Cardiovascular
Disease, and Cancer in 17,013 Canadians (18-90 yr) followed
for an average of 12 yrs
Katzmarzyck P., et al. Med Sci Sport Exerc 41:998,2009.

18. Television Watching in Relation to Risk of Obesity
Association between TV watching,
and Type 2 Diabetes in Women
Obesity and Type 2 Diabetes in Women
Independent of exercise watching TV was associated with significantly
elevated risk of obesity and type 2 diabetes, whereas light to moderate activity
was associated with substantially lower risk.
Hu F. et al. JAMA 289:1785-1791, 2003.

19. Associations between TV time and Sitting time
With Metabolic Syndrome in 1,958 Older Adults
Gardiner PA., et al. JAGS 59:788-796, 2011.
3.00 h/d
2.00 h/d
1.14 h/d
Take home Message?
1. Decrease sitting time
2. Increase physical activity time
6.65 h/d
3.43 h/d
4.99 h/d

20. Does Minimal Intensity Exercise Improve Insulin
Sensitivity in 18 Young (21 yr) Sedentary Subjects?
Duvivier et al. PLoS One 8(2): e55542, 2013.
6 hrs
14 hrs
13.5 hrs
8 hrs
Duration of each condition = 4 days
30 min

21. Does minimal intensity exercise intensity lower
Insulin Sensitivity in Sedentary Subjects?
Duvivier et al. PLoS One 8(2): e55542, 2013.

23. High levels of MVPA are
Associated with reduced Cardiometabolic in
Children Regardless of Sedentary Time.
Type of Sedentary time (eg screen time) may
Be more important that overall Sedentary Time.
Appl Physiol Nutr Metab 38: 477-483, 2013.

24. Excess TV viewing: a special component
of sedentary time?

25. Moderate to Vigorous Physical Activity and Sedentary Time
and Cardiometabolic Risk factors in Children and Adolescents
Ekelund U. et al. JAMA 307(7):704-712,2012
14 studies ; 20,871 ; 4-18 yr
Higher MVPA time in children and adolescents is
Associated with lower Cardiometabolic Risk Factors
Regardless of Sedentary Time

26. SUMMARY

27. Sedentary Lifestyle:
the Smoking of the 21st Century?
Prevalence
Hazard ratio*
Population
Attributable Risk
Global Deaths per Year
5,3 million
5,1 million
35%
26%
Smoking
8,7%
1,57
9,0 %
1,28
Inactivity
Smoking
Inactivity
Smoking
Inactivity
Smoking
Inactivity
Comparison of global burden between smoking and physical inactivity (*from meta-analyses).
Adapted from Wen CP, Wu X The Lancet 2012;380:192-3

28. 150 minutes per week of
moderate (brisk walking) in
bouts of 10 minutes or more.

29. Cardiorespiratory Fitness
Increase physical activity = Increase in cardiorespiratory fitness
~20%
Before
~5 times - 30 min/day
150 minutes /week
After
~4 Weeks

30. Effect of Fatness (BMI) and Fitness on
Cardiovascular Disease (CVD) Mortality
RR of CVD Mortality
Wei M et al. JAMA 1999; 282:1547-53
4.5
3
Fit
Unfit
1.5
0
Normal Weight
Overweight
Obese
“Fit” – top 80 percent – 30 minutes per day of physical activity

31. Association of CRF and PA with Risk of
Developing Hypertension (HTN) in Men
HR
PA
High
Middle
Low
Sport
WJR
Sedentary
WJR = walker/jogger/runner
Sport = other activities (such
as cycling, swimming,
racquet and ball sports)
CRF
Chase et al. Am J Hypertension 2009; 22(4): 417

32. Effect of Acute Exercise on Insulin Sensitivity in
Men and Women
Perseghin et al. N Eng J Med. 335: 1996.
Insulin Sensitivity
(mg/kg, FFM)
18
*
14
20%
10
6
2
0
Baseline Acute
( 1 Day )
* Acute > Baseline

33. A Typical Canadian Day?
Slide courtesy David Dunstan

35. Excess TV viewing: a special component
of sedentary time?

36. www.csep.ca

37. How much Daily Recreational Screen Time?
2 Hours….or less!

38. The Issue of today’s lecture
Sedentarism is real…
….but is it a Unique Public Health Problem?

40. Increasing physical activity behavior in today’s
environment poses a challenge…

41. Importance of Self-Monitoring – Role for Pedometers
Accumulate 15-30 minutes per day
2000 extra steps / day
Goal: 10,000 steps / day

42. Is Exercise the same as Physical Activity?
Exercise is a subset of physical activity
Exercise = ‘structured’ or leisure time activity
Physical activity = ‘unstructured’ leisure and non-leisure activity

43. Walking, Walking Pace and Risk of CHD in Women
Lee et al. JAMA 285(11): 1447, 2001.
Relative Risk
Do Not Walk
Easy
< 3.2 km / hr
50% Reduction
Normal
3.2 – 4.8 km / hr
Brisk
> 4.8 km / hr
Total Walking Time
Do Not Walk
1 to 59 min / wk
1.0 to 1.5 hr / wk
> 2 hr / wk
Walking Pace

44. FREE GYM!

45. Thank You
Merci
rossr@queensu.ca