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Catrine Tudor-Locke

Publications and source records attributed to Catrine Tudor-Locke.

At least 19 recordsLinked to original sources
PubMed2006

Relationship between objective measures of physical activity and weather: a longitudinal study.

BACKGROUND: The weather may be a barrier to physical activity but objective assessment of this hypothesis is lacking. Therefore we evaluated the effect of temperature, rain or snow, and wind speed on the daily physical activity of adults. METHODS: This report contains data from 25 males (BMI (mean +/- SD): 28.7 +/- 3.83 kg/m2) and 177 females (BMI: 29.2 +/- 5.92 kg/m2) enrolled in an intervention to increase physical activity. Steps/day of the participants was measured by pedometer. Weather data were obtained from Environment Canada. A total of 8,125 observations were included in a mixed linear model analysis. RESULTS: Significant weather related variables (at the 5% level) impacting steps/day included: seasonal effects related to the interaction between weekday and month; mean temperature, total rainfall, interactions between gender, BMI and total snow, interactions between maximum wind speed and BMI, and the amount of snow on the ground. The estimated magnitudes for the various effects were modest, ranging from approximately 1% to approximately 20%. Thus for an average individual taking approximately 10,000 steps/day, weather-dependent changes in physical activity could reach 2,000 steps/day. CONCLUSION: We conclude that weather had modest effects on physical activity of participants in an intervention to increase their activity. It should be stressed that these effects may be different for less or more motivated people. With this in mind, we suggest that the effect of weather on physical activity in the general population needs to be objectively assessed to better understand the barrier it poses, especially as it relates to outdoor recreation or work activities.

Journal Article↗
PubMed2006

Reliability of pedometer-determined free-living physical activity data in college women.

This study examined stability and reliability of free-living physical activity assessed by pedometer in 69 young female college students (M age = 18.7 years, SD = 1.2, range: 18-25 years; body mass index = 23.2 kg/m2, SD = 0.6) for two complete weeks (Week 1 and Week 2) separated by 12 weeks. During Week 1, participants took an average of 8880 steps/day, SD = 3219, range: 1858-19480; during Week 2 9088 steps/day, SD = 3299, range 1736-16837; t (68) = -.568, p = .572. In both weeks, only Sunday differed significantly (repeated measures analysis of variance; Week 1: p < .0001; Week 2: p < .01) from all other days of the week. The computed intraclass correlation between weeks was moderate (.72). Group mean pedometer-determined physical activity was stable across 2 weeks separated by 12 weeks in this young, healthy sample of women. Individuals within these groups held their rank order to a moderate extent over time. These findings provide important evidence of the reliability of pedometer-determined physical activity data and are of practical importance to study design.

Adolescent↗
PubMed2006

Pedometer-assessed physical activity in young adolescents.

The purpose of this study was to evaluate the physical activity (PA) patterns of children. Forty-four 7th-grade students (19 boys, 25 girls) recorded pedometer data for 2 consecutive weeks. Separate 2 x 3 repeated measures analyses of variance were used to examine differences in total steps/day between boys and girls and between after-school activity participants and nonparticipants. The relative contribution of physical education (PE) and after-school activity (ASA) to weekday steps/day was evaluated as a proportion, for example (steps taken in PE class/total daily steps taken on a PE class day) * 100. The total sample mean was 11,392 steps/day, SD = 4112; for boys, M = 12,490 steps/day, SD=3910, versus girls, M = 10,557 steps/day, SD=4142; F=(1, 42) 4.365, p = .043. The sample population averaged 2046 steps, SD=945, during PE class; boys=2379 steps, SD=1115, versus girls=1782, SD=703; t (42) = 2.15, p = .038, d = .65, which represented 18% of the total steps/day on PE days. In comparison, the participants accumulated an average of 5366 steps, SD=2590; ASA for boys=5897 steps/day, SD=2738, versus girls=4963 steps/day, SD=2450; t (42) = 1.190, p = .241, d = .36), representing 46% of the steps/day on all weekdays and 47% of the total on PE days. Expressed as a rate, the sample population took 45.5 steps/min (SD=21) during PE class and 13.1 steps/min (SD = 4.7) in ASA on all weekdays. The relative stability of day-to-day behavior in youth is a preliminary finding but noteworthy. Although the absolute contribution ofPE class to daily PA was less than ASA (i.e., 18 vs. 47%, respectively), the importance of the condensed contribution in class was evident when these two activities were expressed as rates (i.e., steps/min). These data indicate that youth involved in ASA accumulated a greater number of steps on all days, weekend days, and health education days when compared to youth not involved in ASA.

Adolescent↗
PubMed2006

Children's pedometer-determined physical activity during the segmented school day.

PURPOSE: To describe the sex-specific patterns of school children's daily pedometer-determined physical (PA) during physical education (PE), recess and lunchtime, and before and after school. METHODS: Eighty-one sixth-grade students (28 boys, age = 11.9 +/- 0.4 yr, BMI = 18.8 +/- 4.1 kg x m(-2); 53 girls, 11.8 +/- 0.5 yr, BMI = 20.2 +/- 4.6 kg x m(-2)) wore pedometers for four school days and were prompted to record steps accumulated at arrival and departure from school and during pre- and postrecess, lunchtime, and PE class. RESULTS: Boys took significantly (P < 0.001) more steps per day than girls: 16,421 +/- 5,444 vs 12,332 +/- 3,056 steps per day, and more steps during release time (e.g., before-school Delta = 1289 steps, recess Delta = 479 steps, lunchtime Delta = 608 steps, and after-school Delta = 1872 steps) but the same number of steps during structured PE classes (1429 +/- 567 vs 1410 +/- 445 steps; P = 0.87). Lunchtime PA represented the most important source of daily PA (15-16%) obtained during school hours for both boys and girls, whereas recess accounted for 8-9% and PE class accounted for 8-11% of total steps per day. Regardless, almost half of daily steps taken are attributable to after-school activities. CONCLUSION: These data provide greater understanding of sex-specific PA patterns and the relative contribution of distinct segments of the school day to school children's total PA.

Child↗
PubMed2005

Active commuting to school among NSW primary school children: implications for public health.

Regular active commuting by walking/cycling can help maintain an active lifestyle. The frequency, duration and correlates of school active commuting were examined for primary school children in NSW, Australia. Walking/cycling-only and in combination with bus/car were of short duration (median 7 or 4 min, respectively) and their frequency dropped within a short distance (>0.75 km) from school. Apart from distance, child's age, school affiliation and perceived safety, regular walking/cycling (10 trips, 22%) was associated with parents' travel mode to work and with father taking the child to school. Frequent walking/cycling (5 trips, 37%) was associated with child's level of independence and the perceived benefits of active commuting. Behaviour change in this setting requires multi-level strategies.

Bicycling↗
PubMed2005

Use of pedometers to measure physical activity in dogs.

OBJECTIVE: To determine whether pedometers can be used to measure physical activity in dogs. DESIGN: Cross-sectional study. ANIMALS: 26 dogs. PROCEDURE: To determine pedometer accuracy, number of steps recorded with the pedometer as dogs walked, trotted, and ran for a distance of approximately 30 m (100 ft) at each gait was compared with actual number of steps. Dogs and owners then wore pedometers for 7 to 14 days, and dog pedometer output was compared with body condition score, owner-reported activity of the dog, and owner pedometer output. RESULTS: Most owners classified their dogs as active or quite active and indicated that their dogs exercised 3 to 7 days/wk. For all dogs, body condition score was 5, 6, or 7 on a scale from 1 to 9. At a walk, pedometers overestimated actual number of steps by approximately 17% in large and medium dogs and underestimated actual number of steps by approximately 7% in small dogs. No significant differences between pedometer-recorded and actual number of steps were detected when dogs trotted or ran. Number of steps per day for the dogs was significantly correlated with owner-reported activity of the dog (r = 0.305) and number of steps per day for the owners (r = 0.469) and was inversely correlated with body condition score (r = -0.554). CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that pedometers can measure physical activity in dogs with reasonable accuracy. A lower number of steps per day was associated with a higher body condition score, and less active owners generally had less active dogs.

Animals↗
PubMed2005

Patterns of walking for transport and exercise: a novel application of time use data.

BACKGROUND: Walking for exercise is a purposeful or structured activity that can be captured relatively easily in surveys focused on leisure time activity. In contrast, walking for transport is an incidental activity that is likely to be missed using these same assessment approaches. Therefore, the purpose of this analysis was to utilize 1997 Australian Bureau of Statistics (ABS) Time Use Survey diary data to describe nationally representative patterns of walking for transport and for exercise. METHODS: Household members >or= 15 years of age were recruited from over 4,550 randomly selected private dwellings in Australia. Time use diaries were collected for two designated days during all four seasons over the calendar year. 3,471 males and 3,776 females (94% household response rate and 84% person response rate) provided 14,315 diary days of data. The raw diary data were coded and summarized into bouts and minutes that included walking for transport and for exercise. RESULTS: Walking for transport was indicated on a higher proportion of days compared to walking for exercise (20 vs. 9%). Based on participant sub-samples ('doers'; those actually performing the activity) walking for transport was performed over 2.3 +/- 1.4 bouts/day (12.5 minutes/bout) for a total of approximately 28 mins/day and walking for exercise over 1.2 +/- 0.5 bouts/day (47 minutes/bout) for a total of approximately 56 mins/day. CONCLUSION: Although walking for transport is typically undertaken in multiple brief bouts, accumulated durations approximate public health guidelines for those who report any walking for transport.

Journal Article↗
PubMed2005

Health and physical activity research as represented in RQES.

In the past 75 years, articles in Research Quarterly for Exercise and Sport (RQES) have contributed to the understanding of the role physical activity plays in the health of individuals and populations. Articles have described laboratory and community research studies in humans and animals, presented reviews of topics and conference proceedings, and presented forums for discussion about current topics in physical activity and health. The articles reflect the growth of the profession from basic inquiry, about physiological responses to exercise (and the development of physical fitness methods and standards), to studies of the effects of exercise on physical fitness and health in various population subgroups. This evolution in RQES reflects the well recognized paradigm shift toward public health concerns for physical activity and health outcomes.

Exercise↗
PubMed2005

Pedometer-determined step count guidelines for classifying walking intensity in a young ostensibly healthy population.

PURPOSE: (a) To establish pedometer steps/min intensity categories (i.e., light, moderate, hard, very hard) for adults under controlled conditions, and (b) use these cut-points to ascertain the number of steps expected in 30 minutes of moderate intensity activity. METHODS: 25 men and 25 women, ages 18-39 years, performed 6-min exercise bouts at 3 treadmill speeds (4.8, 6.4, and 9.7 km/hr). Yamax SW-200 pedometers indicated steps, and steady-state VO2 was recorded. METs were calculated by dividing steady-state VO2 by 3.5 ml x kg(-1) x min(-1). Linear regression was used to quantify the relationships between steps/min and METs across all speeds. Ten participants (5 M, 5 F) were randomly selected from the original 50 and constituted a holdout sample for cross-validation purposes (i.e, comparing actual and predicted METs; paired t-test). RESULTS: The regression equation for males was: METs = -7.065 + (0.105 x steps/min) r2 = 0.803. For females it was: METs = -8.805 + (0.110 x steps/min) r2 = 0.830. Cross-validation was confirmed. CONCLUSIONS: Pedometer cut-points corresponding to minimal moderate intensity walking were 96 steps/min in men and 107 steps/min in women, or roughly 100 steps/min for both. This translates to approximately 3,000 steps in 30 min of moderate-intensity ambulatory activity for both genders.

Adult↗
PubMed2004

BMI-referenced standards for recommended pedometer-determined steps/day in children.

BACKGROUND: Recommended levels of youth physical activity (PA) should emerge from data related to important health outcomes. The purpose of the present study was to establish criterion-referenced standards for PA (using pedometer-assessed steps/day) related to healthy body composition. METHODS: This is a secondary analysis of an existing data set (including pedometer-assessed PA and objectively measured BMI) of 1,954 children (995 girls, 959 boys; ages 6-12 years) from the USA, Australia, and Sweden. The contrasting groups method [M.J. Sarif, Introduction to Measurement in Physical Education and Exercise Science, St. Louis, MO: Mosby College Publishing; 1986] for establishing criterion-referenced cut points was used to identify optimal age- and sex-specific standards for steps/day related to international BMI cut points for normal weight and overweight/obesity. RESULTS: The selected cut points for steps/day for 6-12 year olds were 12,000 steps/day for girls and 15,000 steps/day for boys. CONCLUSIONS: The analytical process undertaken in this study illuminated the difference in previously used norm-referenced standards vs. criterion-referenced standards based on BMI categories. The steps/day cut points established herein, using an international sample, are higher than previously suggested normative standards but are not inconsistent with recent advances in our understanding of PA needs in youth. This analysis provides the foundation for cross-validation and evaluation of these BMI-referenced steps/day cut points in independent samples and with longitudinal study designs.

Body Mass Index↗
PubMed2004

Health benefits of a pedometer-based physical activity intervention in sedentary workers.

BACKGROUND: Inactivity is a leading contributor to chronic health problems. Here, we examined the effects of a pedometer-based physical activity intervention (Prince Edward Island-First Step Program, PEI-FSP) on activity and specific health indices in 106 sedentary workers. METHODS: Participants were recruited from five workplaces where most jobs were moderately-highly sedentary. Using subjects as their own control, physical activity (pedometer-determined steps per day) was compared before and after a 12-week intervention. Changes in body mass index (BMI), waist girth, resting heart rate, and blood pressure were evaluated. RESULTS: The PEI-FSP was completed by 59% of participants. Steps per day increased from 7,029 +/- 3,100 (SD) at baseline to a plateau of 10,480 +/- 3,224 steps/day by 3.96 +/- 3.28 weeks of the intervention. The amount that participants were able to increase their steps per day was not related to their baseline BMI. On average, participants experienced significant decreases in BMI, waist girth, and resting heart rate. Reductions in waist girth and heart rate were significantly related to the increase in steps per day. In contrast, reductions in BMI were predicted by the initial steps per day. CONCLUSIONS: The PEI-FSP increased physical activity in a sedentary population. Importantly, those with a higher BMI at baseline achieved relatively similar increases in their physical activity as participants with a lower BMI.

Adult↗
PubMed2004

Walking patterns in a sample of African American, Native American, and Caucasian women: the cross-cultural activity participation study.

This analysis describes walking patterns among African American, Native American, and Caucasian women from South Carolina and New Mexico. Walking was assessed using pedometer and physical activity (PA) record data based on 4 consecutive days on either three (Study Phase 1) or two (Study Phase 2) occasions. Participants walked 5,429 +/- 2,959 steps per day and recorded 159 +/- 59 minutes per day of total walking in the PA record. Most daily walking was accumulated during household (46%), transportation (26%), occupation (16%), and exercise-related (10%) walking. There was a modest correlation between steps per day and minutes per day. Steps per day were higher with education and household size, and lower with increasing age and body mass index. These findings have implications for developing PA surveys and for planning interventions related to walking patterns among women.

Adult↗
PubMed2004

A preliminary study of one year of pedometer self-monitoring.

BACKGROUND: Long-term pedometer monitoring has not been attempted. PURPOSE: The purpose of this project was to collect 365 days of continuous self-monitored pedometer data to explore the natural variability of physical activity. METHODS: Twenty-three participants (7 men, 16 women; M age = 38 +- 9.9 years; M body mass index = 27.7 +- 6.2 kg/m2) were recruited by word of mouth at two southern U.S. universities. Participants were asked to wear pedometers at their waist during waking hours and record steps per day and daily behaviors (e.g., sport/exercise, work or not) on a simple calendar. In total, participants wore pedometers and recorded 8,197 person-days of data (of a possible 8,395 person-days, or 98%) for a mean of 10,090 +- 3,389 steps/day. Missing values were estimated using the Missing Values Analysis EM function in SPSS, Version 11.0.1. RESULTS: A mean of 10,082 +- 3,319 steps/day was computed. Using the corrected data, differences in steps/day were significant for season (summer > winter, F = 7.57, p = .001), day of the week (weekday > weekend, F = 3.97, p = .011), type of day (workday vs. nonworkday, F = 9.467, p = .008), and participation in sport/exercise (day with sport/exercise > day without sport/exercise, F = 102.5, p < .0001). CONCLUSIONS: These data suggest that surveillance should be conducted in the spring/fall or that an appropriate correction factor should be considered if the intent is to capture values resembling the year-round average.

Adult↗
PubMed2004

Pedometer accuracy in nursing home and community-dwelling older adults.

PURPOSE: The accuracy of pedometers has not been thoroughly tested with older adult populations. The purpose of the present study was to examine the effects of walking speed and gait disorders on the accuracy of Yamax pedometers with nursing home residents (NH) relative to older adults living in the community. METHODS: Pedometer accuracy was evaluated against observed steps taken during a self-paced walking test (slow, normal, and fast speeds) in 26 NH residents and 28 seniors' recreation center members (SC). Devices were attached to clothing at the waist. Walking speed was ascertained from the timed walk and a gait assessment was conducted. Percent error was calculated as ([pedometer steps - observed steps]/observed steps) x 100. RESULTS: The walking speeds of both samples increased across self-selected paces (P < 0.0001). The community-dwelling older adults walked significantly faster (P < 0.0001) in all trials and had significantly higher (P < 0.0001) gait assessment scores (indicating fewer gait problems). Gait scores were positively associated with walking speed and pedometer percent error. Pedometers significantly underestimated NH residents' observed steps taken by 74% (slow), 55% (normal), and 46% (fast) paces (P < 0.0001). In the SC sample, the instruments failed to detect 25%, 13%, and 7% of actual steps taken, respectively (P < 0.0001). The magnitude of the error was greater for NH versus SC older adults (P < 0.0001) across all trials. CONCLUSIONS: Slow walking speed and gait disorders hamper the utility of pedometers for physical activity measurement in frail seniors, such as NH residents, when worn at the usual attachment site. Pedometers, however, can be confidently used with ostensibly healthy older adult populations for both assessment and motivation purposes.

Acceleration↗
PubMed2004

Motion sensor accuracy under controlled and free-living conditions.

PURPOSE: Two studies were conducted to examine the concurrent accuracy of the Yamax SW-200 (YAM), Omron HJ-105 (OM), and Sportline 330 (SL) pedometers, as well as a CSA accelerometer. METHODS: In study 1, motion sensor performance was evaluated against actual (observed) steps taken during 5-min bouts at five different treadmill speeds (54, 67, 80, 94, and 107 m x min) using a two-way repeated measures ANOVA (instrument x speed). Additionally, the direction and magnitude of motion sensor error was examined. In study 2, pedometer performance during 24 h of free-living was evaluated against the steps detected by the CSA criterion. The direction and magnitude of pedometer error was also examined in the free-living condition. RESULTS: In study 1, the SL showed significant differences from actual steps taken at all treadmill speeds (P < 0.05). Further, the absolute value of percent error was greatest for the SL at all treadmill speeds. At the slowest treadmill speed (54 m x min), the absolute value of percent error increased for the YAM and OM. In study 2, only the SL detected fewer steps than the CSA criterion (P < 0.05). The YAM demonstrated the lowest absolute value of percent error under free-living conditions. CONCLUSIONS: Different brands of motion sensors detect steps differently; therefore, caution must be used when comparing step counts between studies that have employed different brands of motion sensors. Taking into consideration the results of both studies and the initial walking test used for instrument screening purposes, it appears that, of the three pedometers tested, the YAM pedometer is most consistently accurate under both controlled and free-living conditions. Future research must consider presenting motion sensor accuracy in absolute terms so that the magnitude of error is not underestimated.

Acceleration↗
PubMed2004

Descriptive epidemiology of pedometer-determined physical activity.

PURPOSE: The dual purposes of this study were: 1) to provide preliminary descriptive epidemiology data representing pedometer-determined physical activity (PA) and 2) to explore sources of intra-individual variability in steps per day. METHODS: All participants (76 males, age = 48.4 +/- 16.3 yr, body mass index (BMI) = 27.1 +/- 5.1 kg x m(-2); 133 females, age = 47.4 +/- 17.5 yr, BMI = 26.9 +/- 5.7 kg x m(-2)) resided in Sumter County, SC, and were recruited by telephone to receive a mailed kit to self-monitor PA for 1 wk. Statistical analyses compared mean steps per day between sexes, races, age groups, education and income levels, and BMI categories. Mean steps per day were also compared between: 1) weekdays versus weekend days, 2) workdays versus nonworkdays, and 3) days of sport/exercise versus no participation. RESULTS: The entire sample took 5931 +/- 3664 steps x d(-1) (males = 7192 +/- 3596 vs females = 5210 +/- 3518 steps x d(-1), t = 7.88, P < 0.0001). Significant differences were also indicated by race, age, education, income, and BMI. In addition, weekdays were significantly higher than weekend days, workdays were higher than nonworkdays, and sport/exercise days were higher than nonsport/exercise days. CONCLUSIONS: The large standard deviations reflect a wide distribution of ambulatory behavior. Regardless, important differences are still evident by demographic characteristics, BMI categories, day of the week, and reported engagement in work or sport/exercise.

Adolescent↗