Development of Step-Count Cut Points for School-Day Vigorous Physical Activity

Background. No study has established step-count cut points for varying amounts of accelerometer-assessed vigorous physical activity (VPA) accrued during the school day in children. The purpose of this study was to establish step-count cut points for discriminating children meeting VPA in 5 minutes, 10 minutes, 15 minutes, and 20 minutes per 7-hour school day. Methods. Participants were a convenience sample of 1,053 children (mean age = 8.4 (1.8) years) recruited from 5 schools from the Mountain West region of the USA. Data within students were observed across multiple semesters totaling 2,119 separate observations. Step counts and time in VPA were assessed using ActiGraph wGT3X-BT triaxial accelerometers that were worn during the entirety of a 7-hour school day for one school week. Average censored step counts and minutes in VPA were calculated across 3 to 5 days. Receiver operating characteristic (ROC) curves were employed to derive step counts via calculation of the maximum Youden J statistic. Results. Area-under-the-curve (AUC) scores ranged from AUC = 0.81 (95% CI: 0.78–0.83; p<0.001) for meeting at least 5 minutes of VPA to AUC = 0.94 (95% CI: 0.88–1.00, p<0.001) for meeting at least 20 minutes of VPA. Approximately 3,460 steps best discriminated children meeting at least 5 minutes of VPA (sensitivity = 74.0%, specificity = 74.0%, and accuracy = 74.1%) and approximately 5,628 steps best discriminated children meeting at least 20 minutes per day of VPA (sensitivity = 85.7%, specificity = 95.1%, and accuracy = 95.1%). Conclusion. Step counts can discriminate with reasonable accuracy children that meet at least 5 minutes of school-day VPA and with strong accuracy children that meet 20 minutes of school-day VPA.

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Step-count guidelines referenced on 60-minutes of moderate/vigorous physical activity

Motriz Revista de Educação Física ◽

10.1590/s1980-65742015000100012 ◽

2015 ◽

Vol 21 (1) ◽

pp. 92-99

Author(s):

Fabio Eduardo Fontana ◽

Michael Pereira da Silva ◽

Ripley Marston ◽

Kevin Finn ◽

Jere Gallagher

Keyword(s):

Physical Activity ◽

Diagnostic Accuracy ◽

Vigorous Physical Activity ◽

Roc Curves ◽

Sixth Grade ◽

Step Count ◽

Step Counts ◽

Sixth Grade Students ◽

Good Diagnostic Accuracy ◽

Full Day

The purpose of this study was to establish step-count guidelines for sixth-grade students and assess the ability of step-counts to discriminate between students achieving and not achieving 60-minutes of moderate to vigorous physical activity daily. 201 sixth-grade students completed the study. They wore a pedometer and an accelerometer at the waist level for one full day. ROC curves were used to establish step-count guidelines and determine the diagnostic accuracy of step-counts. Sixth grade students need 12,118 steps/day to reach adequate daily levels of physical activity. The AUC indicated good diagnostic accuracy of step-counts. Suggested step-count guidelines can be a useful tool for identifying children who need to increase their daily levels of physical activity. The step-count cutoff proposed in this study is adequate for discriminating between sixth grade students reaching and not reaching recommended levels of physical activity.

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Establishing school day pedometer step count cut-points using ROC curves in low-income children

Preventive Medicine ◽

10.1016/j.ypmed.2016.02.018 ◽

2016 ◽

Vol 86 ◽

pp. 117-122 ◽

Cited By ~ 8

Author(s):

Ryan D. Burns ◽

Timothy A. Brusseau ◽

You Fu ◽

James C. Hannon

Keyword(s):

Low Income ◽

Roc Curves ◽

Step Count ◽

Cut Points ◽

Low Income Children ◽

School Day

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A Pilot Study Comparing Pedometer Counts with Reported Physical Activity in Elementary Schoolchildren

Pediatric Exercise Science ◽

10.1123/pes.16.4.355 ◽

2004 ◽

Vol 16 (4) ◽

pp. 355-367 ◽

Cited By ~ 18

Author(s):

Greet Cardon ◽

Ilse De Bourdeaudhuij

Keyword(s):

Physical Activity ◽

Pilot Study ◽

Vigorous Physical Activity ◽

Step Count ◽

Regression Equations ◽

Moderate Correlation ◽

Daily Step ◽

Step Counts ◽

Daily Step Count

In this study pedometer counts were recorded for 6 consecutive days for 92 children (mean age = 9.6 years; range 6.5–12.7) and were compared with the number of minutes per day in which the participants engaged in moderate-to-vigorous physical activity (MVPA). Diaries filled out with the assistance of one of the children’s parents were used to determine minutes of MVPA. The average daily step count was significantly higher in boys than in girls, although the average daily MVPA engagement in minutes did not vary significantly between genders. Based on the regression equations, 60 min of MVPA was equivalent to 15,340 step counts in boys, 11,317 step counts in girls, and 13,130 step counts when results for both genders were combined. A moderate correlation (r = .39, p < .001) was found between pedometer step counts and reported minutes of MVPA. According to the present study findings, however, predictions and promotion of daily MVPA engagement in children based on pedometer counts per day should be made with caution.

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Moderate to Vigorous Physical Activity and Step Count Compilation for Elementary-Aged Youth Participating in Summer Camp Activities

Journal of Park and Recreation Administration ◽

10.18666/jpra-2021-11092 ◽

2022 ◽

Author(s):

Zachary Wahl-Alexander

Keyword(s):

Physical Activity ◽

Weight Gain ◽

Summer Camp ◽

Vigorous Physical Activity ◽

Excess Weight ◽

Step Count ◽

Summer Camps ◽

Step Counts ◽

Residential Camp

The summer months have recently been identified as a time of the year when children gain excess weight. Despite contrary beliefs, youth are more susceptible to weight gain and fitness losses during this time. Summer camps have been identified as a possible solution to reduce declines in overall health during these months. The purpose of this study was to establish expected step counts and moderate to vigorous physical activity (MVPA) values for a variety of activities in one residential camp. Participants included 188 campers (M age = 8.7). Sessions included a variety of invasion, target, net/wall and fitness activities. Step counts and MVPA were tracked across 51 days, incorporating 839 activity sessions using a NL–1000 (New Lifestyle Inc., Lee Summit, MO, USA) accelerometer to track campers’ activity. Means and steps/minute were calculated for each activity. Invasion games represented the greatest opportunity for campers to engage in physical activity. Findings are useful for researchers and practitioners to evaluate physical activity and MVPA at camp settings.

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Abstract MP40: A Steps/Day Translation of the Moderate-to-Vigorous Physical Activity Guideline for Children and Adolescents

Circulation ◽

10.1161/circ.127.suppl_12.amp40 ◽

2013 ◽

Vol 127 (suppl_12) ◽

Author(s):

Marc A Adams ◽

William D Johnson ◽

Catrine Tudor-Locke

Keyword(s):

Physical Activity ◽

Children And Adolescents ◽

Vigorous Physical Activity ◽

Area Under The Curve ◽

Physical Activity Guideline ◽

Accelerometer Data ◽

Predictive Values ◽

Medical Practitioners ◽

Cut Points ◽

Practical Applications

Background: An evidence-based steps/day translation of U.S. federal guidelines for youth to engage in ≥60 minutes/day of moderate-to-vigorous physical activity (MVPA) would help health researchers, medical practitioners, and lay professionals charged with increasing youth’s physical activity (PA). The purpose of this study was to determine the number of free-living steps/day (both raw and adjusted to a pedometer scale) that correctly classified children (6-11 years) and adolescents (12-17 years) as meeting the 60-minute MVPA guideline using the 2005-2006 National Health and Nutrition Examination Survey (NHANES) accelerometer data, and to evaluate the 12,000 steps/day recommendation recently adopted by the President’s Challenge Physical Activity and Fitness Awards Program. Methods: NHANES children (n=915) and adolescents (n= 1,302) were included in this analysis. Receiver Operating Characteristic (ROC) curve plots and classification statistics (i.e., false positive and negatives, positive and negative predictive values) revealed candidate steps/day cut points that discriminated meeting/not meeting the MVPA threshold by age group, gender and different accelerometer activity cut points. The Evenson cut point and two Freedson age-specific (3 and 4 METs) cut points were used to define minimum MVPA, and optimal steps/day were examined for raw steps and adjusted to a pedometer-scale to facilitate translation to lay populations. Results: For boys and girls (6-11 years) with ≥ 60 minutes/day of MVPA, a range of 11,500-13,500 raw steps/day for children was the optimal range that balanced classification errors. For adolescent boys and girls (12-17) with ≥60 minutes/day of MVPA, 11,500-14,000 raw steps/day was optimal. Translation to a pedometer-scaling reduced these minimum values by 2,500 step/day to 9,000 steps/day. Area under the curve was ≥84% in all analyses. Conclusions: A persistent question in the physical activity literature has been “How many steps/day are enough?” No single study has definitively identified a precise and unyielding steps/day value for youth. Considering the other evidence to date, we propose a reasonable ‘rule of thumb’ value of ≥ 11,500 steps/day for both children and adolescents (and both genders), accepting that more MVPA is better. For practical applications, 9,000 steps/day appears to be a more pedometer-friendly value. These steps/day values provide a marker that medical practitioners and lay professionals can use in clinical settings to estimate and increase youth’s moderate-to-vigorous physical activity.

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The Effect of Feedback and Information on Children’s Pedometer Step Counts at School

Pediatric Exercise Science ◽

10.1123/pes.19.1.29 ◽

2007 ◽

Vol 19 (1) ◽

pp. 29-38 ◽

Cited By ~ 20

Author(s):

Zoe Butcher ◽

Stuart Fairclough ◽

Gareth Stratton ◽

David Richardson

Keyword(s):

Physical Activity ◽

Elementary Schools ◽

Step Count ◽

Intervention Period ◽

Short Term ◽

Step Counts ◽

School Time ◽

School Based ◽

School Day ◽

Activity Information

This study examined whether feedback or feedback plus physical activity information could increase the number of pedometer steps taken during 1 school week. One hundred seventy-seven students (mean age 9.124 ± 1.11 years) in three elementary schools participated. Schools were randomly assigned to control (CON), feedback (FB), or feedback plus information (FB+I) groups. Children wore pedometers during school time for 5 consecutive weekdays. The total steps of the groups were recorded at the end of each school day, with students in the FB and FB+I groups free to view their step counts. In addition, the FB+I group received information and ideas about how they could increase their daily steps. The CON group received no step-count feedback or information. Students in the FB+I group achieved significantly more steps per minute (17.17 ± 4.87) than those in the FB (13.77 ± 4.06, p = 0.003) and CON (12.41 ± 3.12, p = 0.0001) groups. Information, as well as step-count feedback, increased elementary students’ school-based physical activity (number of steps) in the short term. A longer intervention period is necessary to assess the sustained impact of this type of approach.

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Comparison of Pedometer and Accelerometer Measures of Physical Activity in Preschool Children

Pediatric Exercise Science ◽

10.1123/pes.19.2.205 ◽

2007 ◽

Vol 19 (2) ◽

pp. 205-214 ◽

Cited By ~ 53

Author(s):

Greet Cardon ◽

Ilse De Bourdeaudhuij

Keyword(s):

Physical Activity ◽

Preschool Children ◽

Vigorous Physical Activity ◽

Step Count ◽

Activity Levels ◽

Accelerometer Data ◽

Strongly Correlated ◽

Daily Step ◽

Step Counts ◽

Daily Step Count

In this study, daily step counts were recorded for 4 consecutive days in 129 four- and five-year-old children. To compare daily Yamax Digiwalker step counts with minutes of engagement in moderate to vigorous physical activity (MVPA), concurrent accelerometer data were collected in a random subsample (n = 76). The average daily step count was 9,980 (± 2,605). Step counts and MVPA minutes were strongly correlated (r = .73, p < .001). The daily step count of 13,874, equating to 1-hr MVPA engagement, was reached by 8% of the children. Daily step counts in preschool children give valid information on physical activity levels—daily step counts in preschoolers are low.

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Abstract P178: Pedometer Feedback Intervention Increases Time Spent in Moderate-to-Vigorous Physical Activity in Cardiac Rehabilitation Patients

Circulation ◽

10.1161/circ.127.suppl_12.ap178 ◽

2013 ◽

Vol 127 (suppl_12) ◽

Author(s):

Cemal Ozemek ◽

Wonwoo Byun ◽

Katrina Riggin ◽

Scott Strath ◽

Leonard Kaminsky

Keyword(s):

Physical Activity ◽

Cardiac Rehabilitation ◽

Vigorous Physical Activity ◽

Activity Level ◽

Step Count ◽

Intensity Level ◽

Activity Levels ◽

Daily Step ◽

Light Physical Activity ◽

Step Counts

Introduction: Pedometer feedback with step goals has previously been demonstrated to be effective in increasing daily steps in cardiac rehabilitation patients. These monitors allow the individual to track steps taken during a day, which may influence the frequency or duration of structured physical activity that is intended to achieve a step goal. However, it is not known whether an increase in step counts by pedometer feedback with step goals also increases time spent in recommended intensity levels for improved health, specifically moderate-to vigorous physical activity (MVPA), in cardiac rehabilitation patients. Hypothesis: Pedometer feedback with weekly step goals will increase time spent in MVPA, mediated by an increase in step counts in cardiac rehabilitation patients. Methods: A total of 31 (22 men and 9 women, age 62 ± 9 years) patients participated in a 12-week maintenance cardiac rehabilitation, pedometer based step goal intervention. Prior to the intervention, each subject’s one week baseline average daily step count was measured and 10% of this value was used to increase step goals during the intervention. Each week the step goal was met, the following week’s goal was appropriately increased. However, if the step goal for the week was not achieved, the step goal would not increase until the goal was fulfilled. Additionally, daily step counts and time spent in MVPA and light physical activity were assessed at baseline (without pedometer feedback) and for each intervention week (with pedometer feedback) using a Kenz Lifecorder PLUS monitor (Nagoya, Japan). Average time spent in light physical activity (activity level of 1-2) and MVPA (activity levels ≥3), were determined according to activity intensity level defined by the manufacturer’s analyses program. Results: The average step count for the baseline week was 5546 ± 2679 steps/day which significantly increased to 8348± 3613 steps/day by week 12 (p<0.01). The average time spent in MVPA also significantly increased (p<0.01) from 19 ± 16 min/day at baseline to 38 ± 23 min/day at week 12. In addition, there was a significant increase (p<0.05) in time spent in light physical activity from baseline (42 ± 18 min/day) to week 12 (51 ± 24 min/day). Conclusion: Findings of this study demonstrate that a 12-week pedometer feedback-based intervention was effective in increasing time spent in MVPA in maintenance cardiac rehabilitation patients. Cardiac rehabilitation facilities can utilize pedometer feedback and goal setting to promote increases in time spent in recommended activity levels previously associated with improved health outcomes.

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How Well iPhones Measure Steps in Free-Living Conditions: Cross-Sectional Validation Study (Preprint)

10.2196/preprints.10418 ◽

2018 ◽

Author(s):

Shiho Amagasa ◽

Masamitsu Kamada ◽

Hiroyuki Sasai ◽

Noritoshi Fukushima ◽

Hiroyuki Kikuchi ◽

...

Keyword(s):

Physical Activity ◽

Linear Trend ◽

Living Conditions ◽

Step Count ◽

Spearman Correlation ◽

Free Living ◽

Convenience Sample ◽

Step Counts ◽

Steps Per Day ◽

Free Living Conditions

BACKGROUND Smartphones have great potential for monitoring physical activity. Although a previous laboratory-based study reported that smartphone apps were accurate for tracking step counts, little evidence on their accuracy in free-living conditions currently exists. OBJECTIVE We aimed to investigate the accuracy of step counts measured using iPhone in the real world. METHODS We recruited a convenience sample of 54 adults (mean age 31 [SD 10] years) who owned an iPhone and analyzed data collected in 2016 and 2017. Step count was simultaneously measured using a validated pedometer (Kenz Lifecorder) and the iPhone. Participants were asked to carry and use their own iPhones as they typically would while wearing a pedometer on the waist for 7 consecutive days during waking hours. To assess the agreement between the two measurements, we calculated Spearman correlation coefficients and prepared a Bland-Altman plot. RESULTS The mean step count measured using the iPhone was 9253 (3787) steps per day, significantly lower by 12% (1277/10,530) than that measured using the pedometer, 10,530 (3490) steps per day (P<.001). The Spearman correlation coefficient between devices was 0.78 (P<.001). The largest underestimation of steps by the iPhone was observed among those who reported to have seldom carried their iPhones (seldom carry: mean −3036, SD 2990, steps/day; sometimes carry: mean −1424, SD 2619, steps/day; and almost always carry: mean −929, SD 1443, steps/day; P for linear trend=.08). CONCLUSIONS Smartphones may be of practical use to individuals, clinicians, and researchers for monitoring physical activity. However, their data on step counts should be interpreted cautiously because of the possibility of underestimation due to noncarrying time.

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Calibration and Cross-Validation of Accelerometer Cut-Points to Classify Sedentary Time and Physical Activity from Hip and Non-Dominant and Dominant Wrists in Older Adults

Sensors ◽

10.3390/s21103326 ◽

2021 ◽

Vol 21 (10) ◽

pp. 3326

Author(s):

Jairo H. Migueles ◽

Cristina Cadenas-Sanchez ◽

Juan M. A. Alcantara ◽

Javier Leal-Martín ◽

Asier Mañas ◽

...

Keyword(s):

Physical Activity ◽

Older Adults ◽

Cross Validation ◽

Sedentary Time ◽

Vigorous Physical Activity ◽

Area Under The Curve ◽

Cut Points ◽

Metabolic Equivalents ◽

Sample Characteristics ◽

Accelerometer Cut Points

Accelerometers’ accuracy for sedentary time (ST) and moderate-to-vigorous physical activity (MVPA) classification depends on accelerometer placement, data processing, activities, and sample characteristics. As intensities differ by age, this study sought to determine intensity cut-points at various wear locations people more than 70 years old. Data from 59 older adults were used for calibration and from 21 independent participants for cross-validation purposes. Participants wore accelerometers on their hip and wrists while performing activities and having their energy expenditure measured with portable calorimetry. ST and MVPA were defined as ≤1.5 metabolic equivalents (METs) and ≥3 METs (1 MET = 2.8 mL/kg/min), respectively. Receiver operator characteristic (ROC) analyses showed fair-to-good accuracy (area under the curve [AUC] = 0.62–0.89). ST cut-points were 7 mg (cross-validation: sensitivity = 0.88, specificity = 0.80) and 1 count/5 s (cross-validation: sensitivity = 0.91, specificity = 0.96) for the hip; 18 mg (cross-validation: sensitivity = 0.86, specificity = 0.86) and 102 counts/5 s (cross-validation: sensitivity = 0.91, specificity = 0.92) for the non-dominant wrist; and 22 mg and 175 counts/5 s (not cross-validated) for the dominant wrist. MVPA cut-points were 14 mg (cross-validation: sensitivity = 0.70, specificity = 0.99) and 54 count/5 s (cross-validation: sensitivity = 1.00, specificity = 0.96) for the hip; 60 mg (cross-validation: sensitivity = 0.83, specificity = 0.99) and 182 counts/5 s (cross-validation: sensitivity = 1.00, specificity = 0.89) for the non-dominant wrist; and 64 mg and 268 counts/5 s (not cross-validated) for the dominant wrist. These cut-points can classify ST and MVPA in older adults from hip- and wrist-worn accelerometers.

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