350 likes | 575 Views
Pedometers and Public Health. Catrine Tudor-Locke, PhD, FACSM Associate Professor of Health Promotion Walking Research Laboratory Department of Exercise and Wellness Arizona State University. Internal Mechanism. Hardware Pedometer. Software Guidelines Protocols
E N D
Pedometers and Public Health Catrine Tudor-Locke, PhD, FACSM Associate Professor of Health Promotion Walking Research Laboratory Department of Exercise and Wellness Arizona State University
Hardware Pedometer Software Guidelines Protocols Detailed program templates Mass Distribution isNot the Answer
Practical Pedometry • Expected values • Standard protocols • Screening • Surveillance • Program evaluation • Step indices • Intervention tool
Summary of validity evidence • Review of 25 articles since 1980 • median r=.86 with different accelerometers • median r=.82 with time in observed activity • median r=.68 with different measures of energy expenditure • median r=-.38 with self-reported sitting time • median r=.33 with self-reported physical activity Tudor-Locke et al., Sports Med 2002
Free-living: Pedometer vs. accelerometer Tudor-Locke et al., MSSE 2002
Effects of walking speed Speed (m/min) Le Masurier, Keup, Tudor-Locke Medicine and Science in Sport and Exercise, 2004
Can we use pedometers with older adults? • 26 nursing home residents and 28 similarly aged community dwelling older adults • Self-selected walking at slow, normal, fast paces • Pedometers underestimated actual steps taken in dependent older adults by 74% (slow) to 46% (fast). • The percent error for the independent older adult sample ranged from 25% (slow) to 7% (fast). Cyarto, Myers, and Tudor-Locke Medicine and Science in Sport and Exercise, 2004
Pedometer vs. dual-mode CSA • Motor vehicle travel on paved roads • total distance traveled was 32.6 km or 20.4 miles • Any steps detected during motor vehicle travel were considered error • the CSA detected approximately 17-fold more erroneous steps than the pedometer • approximately 250 vs 15 steps for the total distance traveled, P < .05 Le Masurier and Tudor-Locke MSSE 2003
Can we use pedometers with obese people? • 16 normal weight, 8 overweight, 11 obese • Self-selected walking at slow, normal, fast paces • Percent error (NS) • normal weight= 2.64.2% • overweight=1.72.8% • obese=4.04.3% Elsenbaumer and Tudor-Locke, Medicine and Science in Sport and Exercise, 2003
Distributions Tudor-Locke et al., Medicine and Science in Sport and Exercise, 2004
Patterns Tudor-Locke et al., Annals of Behavioral Medicine, 2004
Breaking down the patterns Tudor-Locke et al., Research Quarterly for Exercise and Sport, 2001
Legend 1=8-10 year olds 2=14-16 year olds 3= Healthy younger adults (approx. 20-50 years) 4= Healthy older adults (>50 years) 5= Individuals living with disabilities and chronic illnesses Tudor-Locke, Research Digest, 2002
Sedentary lifestyle index Tudor-Locke et al., International Journal of Obesity, 2001
How Many Steps Are Equivalent to Current Public Health Recommendations?
The Evidence • 3,800-4,000 steps in 30 minutes extrapolated from distance walked data at different paces set externally (Welk et al., 2000) • 3,100 steps during unsupervised 30 minute walk (intensity not reported) included in a typical day of activity (Wilde et al., 2001) • 3,400 steps during 30 minute group continuous group walk at self-selected pace (Tudor-Locke et al., 2001)
Controlled Conditions Tudor-Locke et al., Canadian Journal of Applied Physiology, in press
Field conditions: Self-select moderate pace • 3,600 steps in 30 minutes of self-paced moderate intensity walking (ICC=.96) • No difference in steps taken based on gender Tudor-Locke et al., in progress
The latest…. • Dose Response to Exercise in Women (DREW) • 8kcal/kg/week = 100% of public health recommendations • Free-living activity 4600 steps/day • 5500 steps/session, 3 days/week Jordan et al., Medicine and Science in Sports and Exercise, 2005
Modeling change • Baseline = 5000 steps/day • 30 minute walk, 3 days/week = 6200 steps/day (60 min/3 days =7500/steps/day) • 30 minute walk, 5 days/week = 7100 steps/day (60min/5days = 9200 steps/day) • 30 minute walk, 7 days/week = 8000 steps/day (60 min/7days =11000 steps/day)
Pedometer-based Interventions • Yamanouchi et al. (1995) RCT • First to look at 10,000 step/day goal • Dieting patients (living in hospital) with type 2 diabetes took 19,200 steps/day and lost 17lbs over 6-8 weeks compared to control group that averaged 4,000 steps/day and lost 9 lbs
Seems Reasonable for Healthy Adults • Assembled from published literature, healthy adults take between 7,000-13,000 steps/day (Tudor-Locke and Myers, 2001) • 73% of participants who reported 30 minutes of moderate activity also achieved 10,000 steps (Welk et al., 2000)
However…. • Even with a prescribed walk, 38-50% of sedentary women reached 10,000 steps on any single day (Wilde et al., 2001) • Only half of healthy older exercisers ever achieved 10,000 steps on any single day, despite the fact that they participated in exercise class or informal walking for exercise on most days of observation (Tudor-Locke et al., 2002)
Further… • When all accumulated minutes are considered, guidelines can be achieved within as little as 8000 steps/day (Tudor-Locke et al., 2002) • Although individuals achieving >10,000 steps/day are more likely to achieve guidelines, that alone is not a guarantee of meeting them (Le Masurier et al., 2003)
And…. • Iwane et al. (2000) described experiences implementing a 10,000 step/day program in a manufacturing work place • 730 volunteered to participate out of 2474 workers (approximately 30%) • 306 remained in program after 4 weeks (42% drop out) • Only 83 remained after 12 weeks (89% drop out from beginning of program)
8-10 year olds in the U.K. take 12,000-16,000 steps/day (Rowlands et al., 1999) 6-12 year olds in the U.S. take 11,000-13,000 steps/day (Vincent et al., 2002) 14-16 years olds in the U.S. take 11,000-12,000 steps/day (Wilde, 2002) Too Low for Children
International sample (USA, Sweden, Australia) 995 girls, 959 boys, 6-12 years Criterion referenced analysis approach 12,000 steps/day for girls 15,000 steps/day for boys BMI-referenced cutpoints Tudor-Locke et al., Preventive Medicine, 2004
Assembled from published literature: 3,500-5,500 steps/day for individuals living with disabilities and chronic illnesses (Tudor-Locke and Myers, 2001) Proposed sedentary lifestyle index is <5,000 steps/day (Tudor-Locke et al., 2001) Achieving 10,000 steps/day requires a 2-3 fold increase in daily activity Too High for Sedentary Individuals
>12,500 steps/day highly active >10,000 steps/day active 7,500-9,999 steps/day somewhat active 5,000-7,499 steps/day low active <5,000 steps/day sedentary Preliminary guidelines for adults Tudor-Locke & Bassett, Jr., Sports Medicine, 2004