Sitting too much is not the same as exercising too little. Travis Saunders, CSEP-CEP, PhD (c)

Transcription

1 Sitting too much is not the same as exercising too little Travis Saunders, CSEP-CEP, PhD (c)

2 Who am I? PhD Candidate in Human Kinetics at the Children s Hospital of Eastern Ontario Research Institute and the University of Ottawa Studying the impact of acute and chronic sedentary behaviour on chronic disease risk in children and youth Also a CSEP-CEP, and a proud New Brunswicker

3 Learning Outcomes At the end of this session, you will be able to: 1. Describe what sedentary behaviour is 2. Distinguish between sedentary and non-sedentary behaviours 3. Identify the general association between sedentary behaviour and chronic disease

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5 What is sedentary behaviour? Image:

6 How does it differ from physical activity? Image:

7 What is Sedentary Behaviour? Any waking activity with an energy expenditure 1.5 METs Sedentary Light PA Moderate PA Vigorous PA Metabolic Equivalents

8 Spot the sedentary behaviours Image:

9 Spot the sedentary behaviours Image:

10 Spot the sedentary behaviours

11 Spot the sedentary behaviours Image:

12 Spot the sedentary behaviours Image:

13 Spot the sedentary behaviours

14 Spot the sedentary behaviours Image:

15 What is Sedentary Behaviour? Any waking activity with an energy expenditure 1.5 METs Sedentary Light PA Moderate PA Vigorous PA Metabolic Equivalents

16 Who is Physically Active? A person meeting Canada s Physical Activity Guidelines = Active A person not meeting the Guidelines = Inactive

17 Can an active person also be very sedentary?

18 Sedentary Behaviour Physical Activity Both Sedentary & Active? Sedentary & Inactive Sedentary & Active Inactive, Not Sedentary Active, Not Sedentary

19 Both Sedentary & Active? From Dunstan et al (Touch Briefings)

20 Active, Sedentary, or Both? Adult woman Cashier at grocery store Takes public transit to work Doesn t like going to the gym Watches 1 half-hour show before bed Not Active, Not Sedentary

21 Active, Sedentary, or Both? Adult man 45 minute run every morning Drives to work Works a desk job Drives home Eats frozen dinner Watches TV until falling asleep

22 How Sedentary Are We?

23 How Sedentary Are Canadian Adults? Sedentary Light PA Moderate PA Vigorous PA 9.5 Hours Colley et al (Health Reports)

24 How Sedentary Are Canadian Kids? Sedentary Light PA Moderate PA Vigorous PA 8.5 Hours Colley et al (Health Reports)

25 How Sedentary Are Canadian Kids? Canadian children and Youth average 6 hours/day of screen time on weekdays Over 7 hours per day on weekends.

26 Questions?

27 Why should we care about chronic sedentary behaviour?

28 Question If a person is physically active, does it matter how much time they spend sitting? What would be a problem of sitting too much? Are there any problems related to sitting too little?

29 Morris Bus Study: Active or Not Sedentary? Morris JN, Heady JA, Raffle PAB, Roberts CG, Parks JN. Coronary heart disease and physical activity of work. Lancet 1953;ii: ; Image:

30 Morris Bus Study: Active or Not Sedentary? Hamilton et al, 2007 (Diabetes)

31 What is Sedentary Behaviour? Sedentary Light PA Moderate PA Vigorous PA Metabolic Equivalents

32 Risk of Death Sedentary Time and Risk of Death % 36% 54% 0 25% 50% 75% 100% % Time Spent Sitting Katzmarzyk et al., MSSE. 41(5):

33 Deaths per 10,000 person-years Sedentary Time and Risk of Death Active Inactive p< p= <25% 25% 50% 75% >75% Time Spent Sitting (%) Katzmarzyk et al, 2009 (MSSE)

34 Risk of Cardiovascular Events (Hazard Ratios) Sedentary Behaviour and CVD % 110% <2 hours/day 2-4 hours/day >4 hours/day Screen Time Stamatakis, 2011 (J Am Coll Cardiol)

35 Sedentary Behaviour and Mortality Systematic Review: there is strong evidence for a relationship between sedentary behavior and mortality from all causes and from CVD, but no evidence for the relationship between sedentary behavior and mortality from cancer. Proper, 2011 (Am J Preventive Med)

36 Sedentary Behaviour and Mortality Life Table Analysis: Compared TV viewing with time persons may be who associated watch no with TV, a those loss of life who that spend is comparable a lifetime average to other of major 6 h/day chronic disease watching risk TV factors can expect such as to physical live 4.8 inactivity years less. and obesity. On average, every single hour of TV viewed after the age of 25 reduces the viewer's life expectancy by 21.8 minutes. Veerman, 2011 (British J Sports Med)

37 Sedentary Behaviour and Mortality = Regardless of physical activity

38 Sedentary Behaviour and Chronic Disease Systematic Review: In general, consistent fındings exist with respect to engaging in high levels of sedentary behavior and increased risk for diabetes and site-specifıc cancers; including ovarian, colon, and endometrial cancer Thorp, 2011 (Am J Preventive Med)

39 Sedentary Behaviour and Chronic Disease Systematic Review: elevated Based on levels the fındings, of sedentary there is behavior a reasonable were consistently level of evidence to conclude associated associations with weight between gain sedentary behavior in both and men health and outcomes in women. are Importantly, not mediated these by time associations remained spent physical following activity further adjustment for physical activity. Thorp, 2011 (Am J Preventive Med)

40 Sedentary Behaviour in Children Systematic Review: During childhood and/or adolescence, engagement in sedentary behavior was consistently shown to predict obesity and increased BMI in adulthood. These relationships were independent of BMI during childhood/adolescence and time spent in physical activity Thorp, 2011 (Am J Preventive Med)

41 Sedentary Behaviour in Children Systematic Review: 232 studies including 983,840 participants met inclusion criteria and were included in the review. Watching TV for more than 2 hours per day was associated with unfavourable body composition, decreased fitness, lowered scores for self-esteem and pro-social behaviour and decreased academic achievement. Tremblay, 2011 (Int j Beh Nutr and Phys Act)

42 Prevalence of MetS (%) Sedentary Behaviour in Children Screen Time(Hours/day) Mark et al, 2008 (JPH)

43 Less Sedentary Behaviour = Less Body Weight Epstein, 2008 (Arch Intern Med)

44 Less Sedentary Behaviour = Less Body Weight Epstein, 2008 (Arch Intern Med)

45 Less Sedentary Behaviour = Less Body Weight No change in physical activity levels Epstein, 2008 (Arch Intern Med)

46 Sedentary Behaviour in Children Systematic Review: Meta-analysis was completed for randomized controlled studies that aimed to reduce sedentary time and reported change in body mass index (BMI) as their primary outcome. In this regard, a meta-analysis revealed an overall significant effect indicating an overall decrease in mean BMI associated with the interventions Tremblay, 2011 (Int j Beh Nutr and Phys Act)

47 Questions?

48 Does it matter how you accumulate sedentary behaviour?

49 Breaks In Sedentary Time Dunstan et al, 2010 (Touch Briefings)

50 Benefits of Breaks in Sedentary Time Independent of total sedentary time and moderateto-vigorous intensity activity time, increased breaks in sedentary time were beneficially associated with waist circumference, BMI, triglycerides, and 2-h plasma glucose. Healy, 2008 (Diabetes)

51 Questions?

52 90 second stretch break

53 Why should we care about acute sedentary behaviour?

54 5 Days of Bed Rest = Reduced Metabolic Health Hamburg, 2007 (ATVB)

55 % Increase 5 Days of Bed Rest = Reduced Metabolic Health Fasting Insulin Insulin Resistance Triglycerides Hamburg, 2007 (ATVB)

56 Impact of 1 Day of Sitting 14 Healthy Adults 2 Conditions 1. Standing for an entire day 2. Sitting for an entire day Stephens, 2011 (Metabolism)

57 1 Day of Sitting = Reduced Insulin Sensitivity Whole-body insulin action 39% Reduction 1 Day Standing 1 Day Sitting Stephens, 2011 (Metabolism)

58 My thesis Does 1 day of sitting increase cardiometabolic risk in healthy children and youth aged 10-14?

59 1 Hour of Video Games=Increased Food Intake Net surplus of 163 kcal Chaput, 2011 (Am J Clin Nutr)

60 Caloric Intake (kcals) Mental Work = Increased Food Intake Calories Sitting Quietly Reading-Writing Test Questions Chaput, 2008 (Psychosomatic Medicine)

61 What are the physiological mechanisms behind sedentary behaviour?

62 Physiological Mechanisms Lipoprotein Lipase Hamilton, 2007 (Diabetes)

63 Physiological Mechanisms GLUT4 Megeney, 1993 (Am J Phys Endo & Metab)

64 Physiological Mechanisms GLUT4 Megeney, 1993 (Am J Phys Endo & Metab)

65 Ways to Reduce Sedentary Behaviour

66 Is Sitting Required, Or Simply the Default? vs

67 Is Sitting Required, Or Simply the Default? vs

68 Is Sitting Required, Or Simply the Default? vs

69 Is Sitting Required, Or Simply the Default? $25!

70 Is Sitting Required, Or Simply the Default? Findings: Time Sitting Reduced by 90 Minutes/day Steps/day Increased by 2700 steps Waist Circumference Reduced by 5cm John, 2011 (J Phys Act & Health)

71 Is Sitting Required, Or Simply the Default? Drive Medical Pedal Exerciser $23 on Amazon.com

72 Ways to reduce screen time Watch specific shows - avoid channel surfing Shut off on evenings and weekends Set screen time limits for kids Some software options may help

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74 Take Breaks During commercial breaks Drink lots of water Software may help here as well

75 Assessing Sedentary Behaviour Unfortunately, no great tools at the moment Accelerometers are ideal, but costly (~$500/each) Self-report questionnaires have lots of error, but are very affordable (e.g. IPAQ) Software may be useful here as well

76 Remember It s not about standing all the time, it s about sitting less

77 Learning outcomes revisited 1. Sedentary behaviour is any behaviour with a low energy expenditure ( 1.5 METs) 2. Sedentary behaviours and non-sedentary behaviours are distinguished by their level of energy expenditure 3. In general, people who sit more die sooner

78 Conclusions 1. Sedentary behaviour is an important and extremely prevalent risk factor for chronic disease in both children and adults 2. Sedentary time can be reduced using relatively simple and inexpensive interventions 3. Reductions in sedentary time are likely to result in reduced risk for multiple chronic diseases

79 Sedentary Behaviour Research Network

80 Obesity Panacea

81 Healthy Active Living & Obesity Research at CHEO www. Haloresearch.ca

82 Thanks!