Credit: Zach Fitzgerald

1. Step by Step: Brief History of Ambulatory Activity Measurement and its Application to Rehabilitation Sciences Credit: Zach Fitzgerald Catrine Tudor-Locke, PhD, FACSM

3. Assessment

4. Intervention

5. Practical Pedometry • Expected values • Standard protocols • Screening • Surveillance • Program evaluation • Step indices • Intervention tool

6. 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

8. Normative data 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

9. Normative data Tudor-Locke et al., International Journal of Obesity, 2001

10. Normative data Tudor-Locke et al., Medicine and Science in Sport and Exercise, 2004

11. Patterns Tudor-Locke et al., Annals of Behavioral Medicine, 2004

12. Breaking down the patterns Tudor-Locke et al., Research Quarterly for Exercise and Sport, 2001

13. Yamax pedometer- SW Series Raw Outputs: Steps Derived Outputs: Steps/day Steps/min Cost: US$17-22 Yamax Corporation, Tokyo, Japan

14. ActiGraph Raw Outputs: Steps Activity Counts Time in intensity categories Energy expenditure ActiGraph, LLC,; Pensacola, FL Cost: US$249/unit + Cable/software

15. NL-1000 Raw Outputs: Steps Distance Time in MVPA Cost: US$50 New-Lifestyles, Inc., Lee Summit, MO

16. activPAL Professional Outputs: Steps Time in sitting, standing, ambulating Transitions Sit/stand bouts Energy expenditure Cost: Initially $US1450 Software, docking station, unit $US950 additional units PAL Technologies, LTD, Glasgow

17. A step is not a step is not a step

18. Effect of censoring – whole sample Tudor-Locke et al., Medicine and Science in Sport and Exercise, 2009

19. What I Do and Do Not Know Now What I know now Commercial items Patents Change Buyer beware Choose, rationalize, and justify your own choice What I don’t know The best instrument for all situations How well they translate Obsolescence Future

20. 2005-2006 NHANES (20+ year olds) Tudor-Locke et al., Medicine and Science in Sport and Exercise, 2009

21. Hour-by-hour time patterns Tudor-Locke et al., Journal of Physical Activity and Health, 2011

22. Expected values for special populations Tudor-Locke et al., Preventive Medicine, 2009

23. Translating recommendations

24. Accept earlier notions 10,000 steps/day!

25. Inspiration • 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

26. Seems Reasonable for Healthy Adults • Assembled from published literature, healthy adults take between 7,000-13,000 steps/day (Tudor-Locke and Myers, 2001)

27. Too High for Sedentary Individuals • 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

28. Translating recommendations: 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)

29. Translating recommendations • 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)

30. Tudor-Locke et al., Preventive Medicine, 2011

31. Translating recommendations: laboratory study Tudor-Locke et al., Canadian Journal of Applied Physiology, 2005

32. Meta-analysis of change in steps/day in pedometer-based programming Bravata et al., JAMA, 2007

33. 12,500+ steps/day Highly Active Graduated Step Index 10,000-12,499 steps/day Active 7,500-9,999 steps/day Somewhat Active 5,000-7,499 steps/day Low Active Sedentary Lifestyle Tudor-Locke and Bassett, 2004

34. Figure 1: Predicted steps/day for 5, 10, 20, 30, 40, 50 and 60 min/day of moderate to vigorous physical activity (MVPA) in 20+ year old females (□) and males (●): NHANES 2005-2006 (n = 3,523). Tudor-Locke et al., Preventive Medicine, 2011

35. Figure 2: Accelerometer-determined mean and 95% confidence intervals of time (min/day) spent in moderate-to-vigorous physical activity (MVPA) by incremental steps/day category in 20+ year old participants: NHANES 2005-2006. Tudor-Locke et al., Preventive Medicine, 2011

36. 10,000+ steps/day Highly Active At least 3,000 steps at moderate+ intensity, over and above daily activities 7,500-9,999 steps/day Active 5,000-7,499 steps/day Low Active 2,500-4,999 steps/day Sedentary Lifestyle Limited Activity <2,500 steps/day BasalActivity Graduated Step Index Adapted from Tudor-Locke and Bassett, 2004 and Tudor-Locke et al., 2009

37. U.S. • Australia • Belgium • Brazil • Canada • France • England How Many Steps are Enough: Consensus Makers • Ireland • Puerto Rico • Japan • New Zealand • Scotland

38. At least 6,000 daily steps in moderate-to-vigorous physical activity At least 15,000 steps/week in moderate-to-vigorous physical activity, e.g., 3,000 daily steps in moderate-to-vigorous physical activity most days of the week Boys 6-11 years Girls 6-11 years Steps/day Adolescents 12-19 years Pre-school children 4-6 years Adults 20-65 years Healthy older adults 65+ years Arrows indicate that higher is even better Individuals living with disability and/or chronic illness Additional benefits can come from adding in vigorous intensity activity Tudor-Locke et al., IJBNPA, 2011

39. Criterion-referenced Normal weight Overweight/obese Frequency Steps/day

40. Optimal Cutting Score True Normal Weight True Over Weight/ Obese False Over weight/ Obese False Normal Weight Criterion-referenced cut points Tudor-Locke et al., JPAH, 2008

41. BMI-referenced cutpoints: adults • International sample Australia, Canada, France, USA and Sweden • 3,127 adults 18 to 94 years (976 males, 2,151 females) • Best estimated cutpoints for normal vs. overweight/obesity ranged from 11,000 to 12,000 steps/day for males and 8,000 to 12,000 steps/day for females (consistently higher for younger age groups). Tudor-Locke et al., JPAH, 2008

42. Cadence

43. Alternative Terms for Cadence • Step frequency • Step rate • Stride frequency • Stride rate • Walking tempo • Steps/min • SPM • Steps.min-1

44. Synthesis of 7 treadmill/track/corridor studies Cadence (steps/minute) r=.97 Speed (miles/hour) METs (ml/kg/min) Metabolic Equivalent (MET); 1 MET=3.5 ml oxygen consumption per kg per minute Tudor-Locke et al., IJBNPA, 2011

45. Cadence (steps/min) 24-hour time clock Tudor-Locke et al., in progress

46. Tudor-Locke and Rowe, Sports Medicine, 2011

47. Tudor-Locke and Rowe, Sports Medicine, 2011