The role of walking in workplace physical activity promotion

Marie H Murphy PhD, FACSMSport & 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)

The decline in physical activity

Pre historic hunting and gatheringhigh energy expenditure survival of the fittest

10,000 yrs ago domesticated animalsrise in farming

1800-1900 Industrial revolutionIncreased urbanisation

Post WWII auto transportlabour saving devices in home and workless strenuous jobs

1950s television1970s video1980s computers1990s internet / www / online shopping

MORBIDITY & MORTALITY

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 InactivitySmoking

Diet

PA and Health: EvidenceCoronary Heart DiseasePhysical activity > 2000kcal per week = 1/3 lower risk of MI (Kohl 2001)

Cardiovascular DiseaseDose-response relationship between walking and CVD up to a 32% risk

reduction (Manson et al 2002)

StrokePhysical inactivity responsible for 3-fold increase in stroke in middle

age men (Wannamethee and Shaper 1992)

Blood LipidsPhysical Activity > 1200kcal per week raises HDL (good) cholesterol

and lowers LDL (bad) cholesterol in hyperlipidemic (Kraus et al 2002)

High Blood PressurePhysical activity normalises moderately elevated blood pressure

(Fagard et al 2001)

PA and Health: Evidence

Overweight and Obesity45-60 mins per day prevents transition from overweight to obese (IASO

2002)

OsteoporosisWeight 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 diabetesRisk of developing diabetes decreases by 6% with each 500kcal per

week of activity (Helmrich et al 1991)

CancerLower 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 deathsBooth 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 -1OR

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

% of

VO2 max

% HR max

METS kcals /min

Feeling

Moderate 40-60% 55-70% 3-7* 5-8# WarmerBreathingConversation

Vigorous 60-85% 70-90% 5-10* 7-12# Warm/HotHeavy breathingConversation difficult

* 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?

Perceived Barriers to Exercise

Not ‘the sporty type’

Facilities

Expense

Not fit / healthy enough

Age

Lack of time

Weather

Lack of social support

How much walking

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

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

Physiological demands of brisk walking

Energy expenditure:

• proportional to body mass

increases with

-speed

-slope

-uneven terrain

-arm movement

Walking not perceived as physical ‘exercise’

How intense is brisk walking?

Is walking intense enough to meet guidelines and elicit health benefits?

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)

Murtagh et al (2002) Preventive Medicine vol 35 p 324-328

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

Murtagh et al (2002) Prev Medicine vol 35 p 324-328

Brisk walking at self-selected pace- is moderate intensity / meets current physical activity recommendations

Is walking intense enough to meet guidelines and elicit health benefits?

•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

Workplace Options for PA promotion

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

Does walking work?

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/day Tudor-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 16 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

Stairclimbing vs WalkingWalking 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

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

Perceived Barriers to Exercise

Not ‘the sporty type’

Facilities

Expense

Not fit / healthy enough

Age

Lack of time

Weather

Lack of social support

Walking

Accumulated approach

Walking / stairclimbing groups

Stairclimbing

Stairclimbing

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, FACSMSport & Exercise Sciences Research Institute

School of Sports Studies