Physical activity and public health

Dose-response of pa and health(hand-out)

Pekka Oja

MPH courseSchlosshofen, 12 January 2008

IntensityFrequencyDurationMode

>60 % VO max3-5/week15-60 minaerobic, continuous

50-75 % VO maxevery day> 30 minvaried, intermittent

Health-enhancingFitness-related

Physical activity

. .2 2

Other resistance training total amount

Lifestyle activity for health M.Murphy: (2004)

• Increasing evidence shows that lifestyle physical activities improve fitness and health of previously inactive people.

• Encourageing, if not yet convinsing, evidence that lifestyle activities are better than traditional exercises in supporting sustained activity behaviour.

Fitness/health dose response

Health

Activity/Fitness

A

B

C

Nonexercise physical activity and mortality in Chinese women

Matthews et al. Am J Epidemiol 165,2007

• 67143 Chinese women

• 40-70 y• free of heart disease,

stroke, cancer• 5,7 y follow-up

• all-cause, CVD, cancer, other cause mortality

• physical activity at baseline– exercise– nonexercise

• housework• walking• cycling• stairclimbing

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Matthews, C. E. et al. Am. J. Epidemiol. 2007 165:1343-1350; doi:10.1093/aje/kwm088

Risk for all-cause mortality, by exercise and nonexercise physical activity, the Shanghai Women's Health Study, 1997-2004

Effects of walking on coronary heart disease

Manson et al 1999:

• 72 488 female nurses, 40-65 years old in 1986

• 8-year follow-up

• incidence of new coronary events– non-fatal Myocardial Infarction– death from coronary causes

0

0,1

0,2

0,3

0,4

0,5

0,6

0,7

0,8

0,9

1

<3.2 (easy or casual)

3.2-4.6(average)

>4.7 (brisk or very brisk)

Age-adjusted

Multivariate

Risk of coronary eventsRelative Risk

Walking PaceManson et al. 1999

Walking and cardiovascular risk factorsA meta-analysis

Murphy et al. Prev Med 44, 2007

24 studies– RCT’s– Walking the only

interventio– Min of 4 weeks

intervention– CV risk factors

measured pre and post

– Subjects sedentary but healthy at baseline

– Subjects 18- y

CV risk factors

– VO2max

– Body weight– Body fat– BMI– SBP– DBP

Walking and cardiovascular risk factorsA meta-analysis

Murphy et al. Prev Med 44, 2007

variable n Wighted mean TE p

VO2max 24 2.73 <0.001

Body weight 27 -0.95 <0.001

Body fat 18 -0.63 0.035

BMI 16 -0.28 0.015

SBP 14 -1.06 0.316

DPB 12 -1.54 0.026

0

2

4

6

8

10

Stairclimbing at work

25 flights per day effective

Treatment Upper 50% Treatment

VO max2

.

%

(l/min)

30 men12 weeksControl using liftsTreatment using stairs

Control

Source: Fardy & Ilmarinen 1975

NS

NS

*

Nordic walking and fitnessKukkonen-Harjula et al. Scand J Med Sci Sports 17,2007

• Randomised study• 121 non-obese

sedentary women, 50-60 y

• 2 groups: walking with or without poles

• Intervention– 13 weeks– 4 times/week– 40 min/session– 52-54 % HRR

• Outcomes– Cardiorespiratory

fitness– Neuromuscular fitness

Nordic walking and fitnessKukkonen-Harjula et al. Scand J Med Sci Sports 17,2007

• HR and lactate at submaximal work decreased equally in both groups

• Both groups improved VO2max similarly

• Leg strength improved more in regular walking group

”Back to the dogs”Tatschl et al. Am J Prev Med 30, 2006

68-year-old Caucasian woman• suffered

– hypertension– hypercholesterolemia– depression – tinnitus

• status– gained 12 kg in 13 years– BMI 28

• physical activity– walked 2-3 times/week

got a golden retriever as gift• status

– lost 7 kg ->BMI 25,5– cholesterol down– in good mood– tinnitus remains

• physical activity– 3 hours daily with dog

• what can a dog do?”Most probably, the woman’s

reduction in weight and cholesterol and regression of the depression were consequences of dog ownership…”

+30 min4 km5000 steps

7 km9000 steps

10 km13000 steps.

+30 min

Daily walking steps for health

Insufficientdaily steps

Sufficientdaily steps

Optimal daily steps

Note: about 5000 steps needed for necessary daily chores

Cycling and all-cause mortalityAndersen et al. Arch Intern Med 160, 2000

• Prospective cohort study

• 13 375 women, 17 265 men, 20-93 y

• Mean follow-up 14,5 y

• All-cause mortality• Cycling

– All cycling– Cycling to work– Changes in cycling

Relative risk of cycling (yes/no)

00,10,20,30,40,50,60,70,80,91

No Yes

MenWomen

• N=8,466 men, 2,389 deaths, p<0.001

• 6,510 women, 1,398 deaths, p<0.01

• Both adjusted for LTPA

• (data from CCPPS)

Cycling

RR of mortality

Changes in cycling over 5 years and subsequent mortality: Copenhagen City Heart Study

00,10,20,30,40,50,60,70,80,91

decreased increased

• Changes in cycling habits among 3291 men and women

• 618 death

Commuting activity and healthHamer & Chida, PrevMed 2007

• Meta analysis• Prospective

epidemiological studies

• 8 studies, 173146 participants

• Health end points– Mortality– Incident CHD, stroke,

hypertension, diabetes

• Overall RR 0.89 (0.81-0.98)

• Women RR 0.87 (0.77-0.98)

• Men RR 0.91 (0.80-1.04)

Is housework good for health?Lawlor et al. JECH 56, 2002

• Brittish Women’s Heart and Health Study

• 2341 women, 60-79 y• national cross-sectional

survey

• health– subjective– CHD– hypertensio– cancer– falls– depression

• physical activity– vigorous exercise– brisk walking– heavy house work

Is housework good for health?Lawlor et al. JECH 56, 2002

Adj OR (95% CL) Adj OR (95% CL) Adj OR (95% CL)

n brisk walking heavy housework

exercise

subjective health, poor

730 0.3 (0.2-0.4) 0.5 (0.4-0.6) 0.3 (0.2-0.4)

CHD 297 o.4 (0.2-0.7) 0.7 (0.5-0.9) 0.6 (0.4-0.9)

hypertension

523 0.8 (0.5-1.1) 1.1 (0.9-1.3) 0.9 (0.6-1.1)

cancer 213 1.3 (0.8-1.9) 0.7 (0.5-0.9) 1.0 (0.7-1.6)

falls 386 0.6 (0.4-0.9) 0.7 (0.6-0.9) 0.9 (0.6-1.2)

depression 400 0.9 (0.7-1.3) 0.8 (0.6-1.0) 0.9 (0.7-1.2)

How effective are lifestyle physical activities for function and health?

• moderate-intensity pa concept = HEPA• daily life-activities: all-cause mortality, hypertension

↓• walking

– brisk walking: CHD and risk factors ↓, function ↑– stair climbing: function ↑– nordic walking ~ brisk walking– 10 000 steps: promising– dog walking ?

• cycling: all-cause mortality ↓, function ↑, accidents ↓ • commuting pa: MI, stroke, type 2 diabetes, colon

cancer, CV risk factors ↓, function ↑ • domestic work: need more studies

Fitness and risk factorsDuncan et al. Arch Int Med 2005;165: 2362-2369

Randomised trial 492 sedentary adults 5 groups

• Control, physician advice• Moderate intensity/low frequency• Moderate intensity/high frequency• Hard intensity/low frequency• Hard intensity/high frequency• All ex. Groups walking 30 min/session

6 and 24 months intervention Outcomes: VO2max, HDL-C, TotC/HDL-C

Copyright restrictions may apply.Duncan, G. E. et al. Arch Intern Med 2005;165:2362-2369.

Mean {+/-} SEM change in maximum oxygen consumption (IMGf1.gif" BORDER="0">O2max) (measured in liters per minute) from baseline to 6 months (A) and

from baseline to 24 months (B) according to treatment condition

ObesitySlentz et al. Arch Intern Med 2004;164:31-39

RCT 120 men and women, 40-65 years, sedentary

overweight with mild to moderate dyslipidemia 4 groups

• Control• High amount/vigorous (~32 km jogging/week)• Low amount/vigorous (~19 km jogging/week• Low amount/moderate (~19 km walking/week

8 months intervention Outcomes: body weight, body composition, waist

circumference

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Slentz, C. A. et al. Arch Intern Med 2004;164:31-39.

Effects of exercise amount and intensity on mean changes in body weight (A), fat mass (B), percent lean body mass (C), and lean body mass (D)

Life expectancyFranco et al. Arch Intern Med 2005; 165: 2355-2360

Prospective cohort study 2336 men 2873 women, 28-62 years Follow-up 12 years Physical acitivity

• Low daily METs• Moderate daily METs • High daily MEDTs

outcome: life ecpectancy at 50 years of age

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Franco, O. H. et al. Arch Intern Med 2005;165:2355-2360.

Effect of physical activity level on life expectancy (LE) at age 50 years

Conclusions

• Vigorous pa > moderate intensity pa– Fitness– CHD risk factors– Obesity– Life expectancy– Type 2 diabetes

• New evidence invites exercise & sport as HEPA