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The role of walking in workplace physical activity promotion. Marie H Murphy PhD, FACSM Sport & Exercise Sciences Research Institute School of Sports Studies. Physical Activity and Health: current activity guidelines Why walking?
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The role of walking in workplace physical activity promotion Marie H Murphy PhD, FACSM Sport & Exercise Sciences Research Institute School of Sports Studies
Physical Activity and Health: current activity guidelines • Why walking? • Walking for short and long term health benefit – the evidence • Stairclimbing • Promoting workplace walking
“All parts of the body which have a function, if used in moderation and exercised in labours in which each is accustomed, become thereby healthy, well developed and age more slowly, but if unused and left idle they become liable to disease, defective in growth and age quickly” Hippocrates (460-370 BC)
Pre historic hunting and gathering high energy expenditure survival of the fittest 10,000 yrs ago domesticated animals rise in farming 1800-1900 Industrial revolution Increased urbanisation Post WWII auto transport labour saving devices in home and work less strenuous jobs 1950s television 1970s video 1980s computers 1990s internet / www / online shopping The decline in physical activity
1900 Measles Polio Diphtheria Tetanus Rubella, Influenza Diarrheal diseases Tuberculosis Pneumonia Food scarcity Vitamin /mineral deficiency 2000 Cardiovascular Disease Overweight and obesity Type 2 Diabetes Osteoporosis Cancer Risk altered by behaviours Physical Inactivity Smoking Diet MORBIDITY & MORTALITY
PA and Health: Evidence Coronary Heart Disease Physical activity > 2000kcal per week = 1/3 lower risk of MI (Kohl 2001) Cardiovascular Disease Dose-response relationship between walking and CVD up to a 32% risk reduction (Manson et al 2002) Stroke Physical inactivity responsible for 3-fold increase in stroke in middle age men (Wannamethee and Shaper 1992) Blood Lipids Physical Activity > 1200kcal per week raises HDL (good) cholesterol and lowers LDL (bad) cholesterol in hyperlipidemic (Kraus et al 2002) High Blood Pressure Physical activity normalises moderately elevated blood pressure (Fagard et al 2001)
PA and Health: Evidence Overweight and Obesity 45-60 mins per day prevents transition from overweight to obese (IASO 2002) Osteoporosis Weight bearing exercise slows and/or reverses decline in bone mineral loss (Dalsky et al 1998) and reduces osteoporotic fractures (Siris et al 2001) Type II diabetes Risk of developing diabetes decreases by 6% with each 500kcal per week of activity (Helmrich et al 1991) Cancer Lower cancer mortality among physically active- strongest relationship breast and colon cancers (Thune 2001)
PA and Health: Evidence Inactivity is physiologically abnormal Sedentary living is a contributory factor to 17 disease conditions and results in ¼ of all preventable deaths Booth et al (2000) J Appl Physiol 88:774-787 “There are few public health initiatives that have greater potential for improving health and well-being than increasing physical activity levels” Prof Sir Liam Donaldson CMO @ Dept of Health
Current Physical Activity Guidelines 30 mins of moderate intensity exercise 5 d.wk -1 OR 20 mins of vigorous intensity 3 d.wk -1 >accumulated in bouts of 10 min or more Haskell et al (2007) Med Sci Sports Exer 39 (8) 1423-1434
Translating Intensity * Age dependent # body weight dependent
Current Physical Activity Guidelines Physical activity guidelines have existed since 1978 Despite guidelines physical inactivity has now reached epidemic proportions 60-70% of adults do not meet current guidelines
What are the main barriers to physical activity among the sedentary majority?
Not ‘the sporty type’ Facilities Expense Not fit / healthy enough Age Lack of time Weather Lack of social support Perceived Barriers to Exercise
Walking • Socially acceptable- no age, gender or race barriers • Little/no skill, equipment or facility requirement • Low impact- low injury risk • Easily incorporated in lifestyle /useful for personal transport • Activity of CHOICE- • Dunn (1998) Project ACTIVE – • sedentary individuals asked to incorporate 30 mins of any additional activity into lifestyle ~ on average added 19-20 mins walking • Dunn et al (1998) Am J Prev Med 15 (4) 398-412 How much walking
Physiological demands of brisk walking • Major muscle groups - over half the body’s muscle mass • Low impact- 1 foot always in contact with ground- low risk of injury
Energy expenditure: • proportional to body mass • increases with • speed • slope • uneven terrain • arm movement Physiological demands of brisk walking
Walking not perceived as physical ‘exercise’ How intense is brisk walking?
28M 54F (mean age 48) walking in park- covertly observed Self selected speed (n=82) - 5.6 km.h -1 (3.5mph) Asked to ‘walk briskly’ (n=59) - 6.4 km.h -1 (4mph) Is walking intense enough to meet guidelines and elicit health benefits? Murtagh et al (2002) Preventive Medicine vol 35 p 324-328
Is walking intense enough to meet guidelines and elicit health benefits? 11 of these subjects walked in lab self selected pace = 59% of VO2 max, 67% of HR max ‘brisk walk’ pace = 69% of VO2 max, 78% of HR max Moderate = 50-70% VO2 max, 60-80% of HR max Brisk walking at self-selected pace- is moderate intensity / meets current physical activity recommendations Murtagh et al (2002) Prev Medicine vol 35 p 324-328
Workplace Options for PA promotion • Facility provision / Membership • Encouraging Active Transport • Promotion of ‘Lifestyle’ activities in and around worksite e.g. • -Walking • -Stairclimbing • Using lifestyle activity:- • Most cost effective • Better long terms adherence • Easy to incorporate into daily routines
Does walking work? Walking and CVD risk factors: Meta-analysis • 24 randomized clinical trials • 1128 subjects, 52 yrs, 83% women • On average 35 week programme, 4.4 days per week, 189 mins per week Murphy et al (2007) Prev Med 44: 377-385
Walking and CVD risk factors: meta-analysis VO2max +2.7 ml/kg/min 9% ↑ Weight -0.95 kg 1.4 % ↓ BMI -0.28 kg/m 21.1 % ↓ Body fat -0.63 % 1.9 % ↓ Systolic BP -1.1 mmHg not sig Diastolic BP -1.5 mmHg 3.4 % ↓ Murphy et al (2007) Prev Med 44: 377-385
Acute Effects At least some of the effects of physical activity are due to the acute effects derived from the most recent bout Such ‘last bout’ effects may be important for health What do we know about the acute effects (0-48 hours) of walking?
Acute Effects of Walking Walking 10 mins 4 times during the course of a day reduces blood pressure for up to 11 hours after the last walk Park et al (2005) J of Hypertension 24 (9) 1761-1770 Three 10 minute walks reduces the lipids circulating in the bloodstream after a meal Murphy et al (1999) Int J of Obesity vol 24 (10) 1303-1309 One 40 minute walks reduces inflammation known to increase risk of a cardiovascular event 24 hours after the walk Murtagh et al (2006) JPAH vol 3, 324-332
How much walking 30 mins minimum 10,000 steps per day from all walking sources Office-based employees typically accumulate 4000-6000 steps/dayTudor-Locke and Bassett (2004). Sports Medicine, 34: 1-8 15000-2000kcal per week Accumulation is as good as continuous Some is good…………………more is better
Stairclimbing • Independent of weather • Suitable for worksite environments where landscape limited • Low cost • No facilities • Inconspicuous • Ideal for accumulated approach • Large Muscle Groups – develops leg strength • Vigorous intensity
Does stairclimbing work • 15 females • 8 weeks progressive stairclimbing: • 1 ascent (195 steps in 135 seconds) per day in week 1 • 6 ascents per day by week 6,7 and 8 • Cadence 90 steps per minute Fitness improved by 17.1% 7.7% decrease in cholesterol Maximum time investment~ 13.5 minutes per day Boreham Kennedy and Murphy (2005) BJSM 39:590-593
Walking Can be low moderate or vigorous intensity Health Benefits Fitness benefits Suits sedentary Suites ‘most’ pre-existing health conditions Stairclimbing Vigorous for all ages – even those already active Health Benefits Fitness Benefits Requires reasonable baseline fitness Not suitable for some pre-existing health conditions Stairclimbing vs Walking Walking is a good start point or a ‘stepping stone’ to …….. Accumulated stairclimbing……. Mixed walking and stairclimbing (interval training)
Walking & Stairclimbing @ worksome practical suggestions Make active choices easy choices: • Map out 10, 20 and 30 minute routes inside + outside workplace • Train some staff as walk leaders • Pedometer challenges (weekly / monthly) • Make stairwells attractive (lighting paint, artwork, music) • Do a walkability audit of your workplace • Put water cooler, toilets or supplies on top floor • Role models / Senior executive ‘champions’ • Active Buddy system • Encourage meetings on the move • ½ hour approved absences • Email prompts • Inactivity monitors
Not ‘the sporty type’ Facilities Expense Not fit / healthy enough Age Lack of time Weather Lack of social support Walking Stairclimbing Accumulated approach Stairclimbing Walking / stairclimbing groups Perceived Barriers to Exercise
Conclusion • Walking and stairclimbing ideally suited to workplace physical activity promotion • Walking can be moderate or vigorous depending on age fitness and chosen terrain • Accumulating exercise is short bouts is as effective as continuous exercise for yielding health benefits • Increasing activity and increasing fitness will both (independently) enhance health and reduce disease risk Take home message: Some physical activity is good……………more is better
The role of walking in workplace physical activity promotion Marie H Murphy PhD, FACSM Sport & Exercise Sciences Research Institute School of Sports Studies