Sitting: How can something feel so good yet be so bad for you? Harry Prapavessis PhD

What does sedentary behaviour look like? Much of our sitting is for work or school Examples – Sitting and using a computer for work or school – Sitting in a car to get to school or work – Sitting and studying – Sitting in class – Sitting and watching TV (Sedentary Behaviour Research Network, 2012)

How do we define sedentary behaviour? Any waking behaviour characterized by an energy expenditure ≤ 1.5 metabolic equivalents (METs) while in a sitting or reclining position (Canadian Society for Exercise Physiology, 2012) One MET is defined as 1 kcal/kg/hour and is roughly equivalent to the energy cost of sitting quietly. A MET also is defined as oxygen uptake in ml/kg/min with one MET equal to the oxygen cost of sitting quietly, equivalent to 3.5 ml/kg/min.

METS and other PA intensities (Owen et al., 2010)

Tremblay et al 2010

Sedentary Behaviour The truth about sitting down

Historical perspective – sitting and health First evidence that inactivity is bad for you was published in the Lancet by Morris et al in 1953 Included in their seminal work was an ecologic study of heart disease mortality and occupational physical activity

Morris et al (1953, Lancet ) Mortality (per 1,000,000) *The data here show a graded inverse relationship.

More recent evidence………..

Health Consequences of Sedentarism Compromises Risk factor for ……. Bone mineral density (Zwart et al., 2007) Vascular health (Demiot et al., 2007) Obesity (Hu et al., 2003) Some Cancers (Schmidt & Leitzmann, 2014)

Sedentary behaviour and health An overview of 27 systematic reviews on sedentary behaviour and health outcomes showed that irrespective of physical activity, time spent in sedentary behaviour is positively associated with – Numerous chronic diseases: fatal and non-fatal cardiovascular disease metabolic syndrome type 2 diabetes several types of cancers (Rezende et al., 2014)

How strong is the association? ► Findings: Irrespective of physical activity level, those who spent the most time sitting were more than two times more likely to have or develop diabetes. Almost twice as likely to die of cardiovascular disease One and a half times more likely to die over the course of the study

Hamburg et al. (2007): Reduced metabolic health after 5 days of bed rest in healthy young adults (Mean age = 30.7 years) Acute effects among young adults

A telomere, the highly repetitive end segment or terminator of a DNA chain that functions as a cap Telomeres stop chromosomes from fraying, clumping together and scrambling genetic code—lifespan is linked to their length (Haycock et al., 2014, BMJ) Scientists have found that the less time people spend sitting, the longer their telomeres (Sjogren et al., 2014, BJSM)

The Active Times The Active Times Become a fan Become a fan Posted: 09/29/ :32 am EDT Updated: 11/26/2014 5:59 am EST Sitting Is the New Smoking: Ways a Sedentary Lifestyle Is Killing You Sedentary living is the 'new smoking' and we're paying for it, study says CBC NewsCBC News Posted: Oct 24, :59 PM ET Last Updated: Oct 24, :33 PM ET Home» Home Life» Life Health & Fitness» Health & Fitness Fitness Sitting is the new smoking, and it’s time to quit ALEX HUTCHINSON Special to The Globe and Mail Published Sunday, Apr , 4:00 PM EDT Last updated Wednesday, Apr , 2:37 PM EDT

Fig. 2. Major contexts for sedentary behaviour and their distribution over a typical adult’s waking hours. (From Dunstan et al. 2010a, reproduced with permission of Touch Briefings, European Endocrinology, Vol. 6, p. 20, # 2010.)

How sedentary are Canadians? ► Canadian adults spend a whooping 9.7 hours of their daily waking hours being sedentary! (Colley et al., 2011)

Measuring free-living PI and PA Sensor->picks up the amplitude and frequency of movement->produces an electrical current of various magnitude (more intense the movement the greater the voltage) Sensor->picks up the amplitude and frequency of movement->produces an electrical current of various magnitude (more intense the movement the greater the voltage) Stores the information as activity counts- >converted to AEE/METS based on default or predetermined cut points Stores the information as activity counts- >converted to AEE/METS based on default or predetermined cut points

What about leisure-time exercise? Physical activity recommendations: minutes of moderate-to- vigorous exercise per day That’s only 2-4% of a 24h day! What about the remaining hours? “I run for 30 minutes every day….surely I can’t be at risk!”

Name of Presentation Owens et al 2010

The “active couch potato” 7:30-8:00am 8:00am-5:00pm 5:00-5:30pm 5:30-6:00pm 7:00-10:00pm Sedentary Sedentary Sedentary Active!!! (30min) Sedentary ► An individual who meets physical activity guidelines but spends most of the day being sedentary

Tremblay et al 2010

Canadian Sedentary Behaviour Guidelines There are none for adults?

15% adults accumulate 150 minutes of moderate to vigorous PA per week Grade-F

Why is such a poor grade? Exercise and physical activity are NOT considered important in our education system—no coherent and consistent curriculum that all primary and secondary students MUST follow Lack of knowledge and awareness in the medical community—medical model is about TREATMENT NOT PREVENTION Thrifty gene (conserve energy and store fat) interaction with obesogenic (move less) environment

Other reasons getting people to exercise more has failed…… Exercising at a moderate-vigorous intensity level is NOT enjoyable People do NOT see immediate benefits from exercise Exercise is OFTEN thought of as activity you do at a special facility People DON’T want to make time for exercise Exercise MAY lead to compensatory behaviour

Most Brits Will Not Exercise To Save Their Lives The majority of adults in the United Kingdom hate the idea of exercising so much that even the threat of premature death does not get them off their backsides, according to a new survey by The British Heart Foundation. Asked whether they would do more exercise if their lives depended on it, a paltry 38% said 'yes'.

Why getting people to sit less may be easier…….. Sitting less is NOT unpleasant (in most circumstances) Strategies for sitting less can be implemented at any time and almost any place Extra time doesn’t have to be made for sitting less Sitting less leads to more incidental PA Incidental PA is easier to do than MVPA for most people Sitting has the potential to become a health and safety issue in the workplace (policy and law)— Kathleen Renner 2007

Levine, 2007 *A calorie can be defined as the energy needed to raise the temperature of 1 gram of water from 14.5 to 15.5C NEAT

Name of Presentation

Improving your NEAT profile

A closer look at BREAKS Interrupt all sedentary behaviour with frequent breaks

Breaking up long periods of sitting Tremblay et al 2010

Name of Presentation

Breaks in sedentary time Lower – Waist circumference – Systolic blood pressure – Glucose – Insulin – Triglycerides Higher – HDL-cholesterol Healy et al. (2008)

Name of Presentation

The effectiveness of breaking up sedentary behaviour ► Dunstan et al. (2012)  Breaks improve glucose levels and insulin levels

PersonEnvironment Behavior B = f(P, E) Lewin 1943 INTERVENTION

To help minimize your sedentary time throughout the day, Apple Watch senses when you stand and move just a bit and gives you credit when you do. And if you’ve been sitting for almost an hour, it reminds you to get up. You close the Stand ring when you’ve stood for at least one minute in 12 different hours during the day. Using Technology…………………….

Intervention: 3 minute breaks after 30 minutes of sitting: Results: 47 minute reduction from 593 minutes of daily sitting (6% reduction).

Name of Presentation

Intervention

Challenge to UWO/OKA Why not become a world leader in promoting a sit less campus………..

Stair prompts that encourage stair use for health benefits have been shown increase stair use by a median of 50% (Soler et al., 2010) Campus signs

What about campus digital signs that promote sitting less and moving more?

Western could decrease car parking spaces, increase separated cycle paths, reconfigure traffic intersections to give active transport modes priority, and increase funding for active transport. Active transportation-riding instead of driving or taking the bus

Active transportation Do I wait minutes for the bus or do I use that time and walk to campus?

Key points to remember: Sedentary behaviour is a major health problem-we simply sit too much Sedentary behaviour vs PA behaviour are distinct (being a regular exerciser does not make up for the negative effects of too much sitting) Change the way you conduct your everyday business (stand more, engage in more incidental PA or non-exercise activity thermogenesis-NEAT) Guard against compensation Use your voice to promote a sit less campus and community (planning and policy) The Public Health Message should focus on reducing sedentary behaviour NOT increasing MVPA

Thank you! Don’t Just Sit There: Stand Up and USE YOUR LEGS More