Four-week pedometer-determined activity patterns in normal weight and overweight UK adults

Predicting ankle joint syndesmotic screw lifetime using finite element and fatigue analysis

After recovery and loading on the patient’s leg, syndesmotic screws mounted on an injured ankle may fail. The main subject of this study is to estimate the lifetime of screws considering the patient’s weight and physical activity. Method: A 3D finite element model of the bone and implemented screws were provided assigning the mechanical properties of ligaments, bones, and screws. Considering axial and tangential physiological loads during the walking phase, the stress and fatigue analyses were performed. Results: The stress distribution had an identical pattern in the screws and all of them experienced the maximum stress during 60–70% of the walking phase. Conclusion: The results of analyses show that body weight has a significant effect on the mounted screw lifetime. Patients with a weight of more than [Formula: see text] kg should prevent applying body load on the operated leg. Conversely, no worry about a patient having less than [Formula: see text] kg body weight.

Public Roads as Places of Interspecies Conflict: A Study of Horse-Human Interactions on UK Roads and Impacts on Equine Exercise

Real or perceived traffic risk is a significant barrier to walking and cycling. To understand whether similar barriers influence equestrians, this study obtained exercise behaviours, road use and experiences of road-related incidents from UK equestrians (n = 6390) via an online questionnaire. Multivariable logistic regression models were used to identify factors associated with road use and experiencing a near-miss or injury-causing incident in the previous year. Content analysis identified themes around equestrians' decisions not to use roads. Our results show that most equestrians (84%) use roads at least once weekly, and in the previous year, 67.7% had a near-miss and 6.1% an injury-causing incident. Road use differs regionally, with exercise type and off-road route availability. Road-using equestrians covered greater daily distances and were younger. However, younger equestrians were at higher risk of near-misses. Respondents' decisions not to use roads were based on individualised risk assessments arising from: the road itself, perceptions of other road users, the individual horse and the handler's own emotional management. Roads were perceived as extremely dangerous places with potentially high conflict risk. Injury-causing incidents were associated with increasing road-use anxiety or ceasing to use roads, the proximity of off-road routes, having a near-miss and type of road use. Targeted road-safety campaigns and improved off-road access would create safer equestrian spaces.

Friday Night Is Pizza Night: A Comparison of Children's Dietary Intake and Maternal Perceptions and Feeding Goals on Weekdays and Weekends

Childhood obesity is a serious issue in the U.S. While obesity is the result of a multitude of factors, a great deal of research has focused on children's dietary intake. While children's eating patterns vary throughout the week, not much else is known about weekday-weekend differences. Therefore, the current study examined differences in the frequency and portion size of school-age children's consumption of common foods and beverages, as well as mothers' perceptions of those items and their child feeding goals, on weekdays and weekends. A total of 192 mothers of children aged 7 to 11 were recruited through Amazon's Mechanical Turk. Results showed a consistent pattern of more frequent consumption and larger portions of unhealthy foods and beverages on weekends. This aligned with mothers' perceptions of those foods and beverages as weekend items, as well as their feeding goals of health and price being less important on weekends. It is quite possible that weekends are viewed as having less structure and facilitate schedules that allow children to consume more meals away from home. These findings shed light on additional risk factors in children's eating patterns and highlight the serious implications that day of the week can have on childhood obesity.

Number of Days Required to Estimate Habitual Activity Using Wrist-Worn GENEActiv Accelerometer: A Cross-Sectional Study

Introduction

Objective methods like accelerometers are feasible for large studies and may quantify variability in day-to-day physical activity better than self-report. The variability between days suggests that day of the week cannot be ignored in the design and analysis of physical activity studies. The purpose of this paper is to investigate the optimal number of days needed to obtain reliable estimates of weekly habitual physical activity using the wrist-worn GENEActiv accelerometer.

Methods

Data are from a subsample of the Mitchelstown cohort; 475 (44.6% males; mean aged 59.6±5.5 years) middle-aged Irish adults. Participants wore the wrist GENEActiv accelerometer for 7-consecutive days. Data were collected at 100Hz and summarised into a signal magnitude vector using 60s epochs. Each time interval was categorised according to intensity based on validated cut-offs. Spearman pairwise correlations determined the association between days of the week. Repeated measures ANOVA examined differences in average minutes across days. Intraclass correlations examined the proportion of variability between days, and Spearman-Brown formula estimated intra-class reliability coefficient associated with combinations of 1–7 days.

Results

Three hundred and ninety-seven adults (59.7±5.5yrs) had valid accelerometer data. Overall, men were most sedentary on weekends while women spent more time in sedentary behaviour on Sunday through Tuesday. Post hoc analysis found sedentary behaviour and light activity levels on Sunday to differ to all other days in the week. Analysis revealed greater than 1 day monitoring is necessary to achieve acceptable reliability. Monitoring frame duration for reliable estimates varied across intensity categories, (sedentary (3 days), light (2 days), moderate (2 days) and vigorous activity (6 days) and MVPA (2 days)).

Conclusion

These findings provide knowledge into the behavioural variability in weekly activity patterns of middle-aged adults. Since Sunday differed from all other days in the week this suggests that day of the week cannot be overlooked in the design and analysis of physical activity studies and thus should be included in the study monitoring frames. Collectively our data suggest that six days monitoring, inclusive of Saturday and Sunday, are needed to reliably capture weekly habitual activity in all activity intensities using the wrist-worn GENEActiv accelerometer.

Does when you eat and exercise matter? Differences in eating and physical activity patterns in overweight and obese adults

PURPOSE

Despite current recommendations and guidelines on the treatment of overweight and obesity, little is known about what patterns of energy intake or expenditure are ideal for weight loss. The present study examined patterns in energy intake and expenditure and explored whether those differences were associated with weight loss.

METHODS

Self-monitoring data on energy intake and expenditure, along with minutes spent in exercise, were obtained from 90 overweight or obese adults (mean BMI = 38.0) enrolled in two behavioral weight loss programs. Energy intake and minutes of daily exercise were self-reported and energy expenditure was obtained from the Caltrac accelerometers that were provided to participants.

RESULTS

On weekends (Friday through Sunday), participants consumed more calories from breakfast (271 vs. 241 kcals/day; p < .01), dinner (605 vs. 547 kcals/day; p < .001), and alcohol (59 vs. 27 kcals/day; p < .01), as well as total daily calories (1669 vs. 1520 kcals/day; p < .001) and expended fewer total calories (2515 vs. 2614 kcals/day; p < .01) than on weekdays. Higher caloric intake on weekdays was associated with less overall weight loss (r = -.29, p < .01) and was marginally associated on weekends (r = -.19, p = .051).

CONCLUSION

This investigation found evidence that while eating patterns clearly contribute to daily energy intake on weekdays and weekends, they may not necessarily contribute to weight change. At the end of the day, what may be most important is regular self-monitoring and total caloric intake on both the weekdays and weekends.

Minute-by-minute stepping rate of daily physical activity in normal and overweight/obese adults

SUMMARY

The relationship between minute-by-minute stepping rate under free-living and obesity remains unclear. The purpose of the present investigation was to compare the levels of physical activity (PA) based on the minute-by-minute stepping rate under free-living conditions between normal weight (NW) and overweight and obese (OV) individuals. A total 40 volunteers participated in the present investigation. These participants were divided into NW or OV according to the body mass index (<25 kg m(-2) or 25 kg m(-2)). All participants wore a pedometer with a uni-axial accelerometer (Lifecorder-EX 4sec, Kenz, Japan) for 7 days continuously. The Lifecorder determined the number of steps and time spent in PA at <100, 100-129, 130 steps min(-1) according to the minute-by-minute stepping rate. The OV group took a significantly fewer number of steps per day in comparison to that in the NW group (p < 0.05). The average daily stepping rate was significantly lower in the OV group in comparison to that in the NW group (p = 0.01). Furthermore, the OV group spent a significantly shorter time in PA at a 100 steps min(-1) of the stepping rate compared with that in the NW group (p < 0.05). These results indicate that obese individuals spent significantly shorter time in PA at 100 steps min(-1) of stepping rate in comparison to the NW individuals.:

Advances in physical activity monitoring and lifestyle interventions in obesity: a review

Obesity represents a strong risk factor for developing chronic diseases. Strategies for disease prevention often promote lifestyle changes encouraging participation in physical activity. However, determining what amount of physical activity is necessary for achieving specific health benefits has been hampered by the lack of accurate instruments for monitoring physical activity and the related physiological outcomes. This review aims at presenting recent advances in activity-monitoring technology and their application to support interventions for health promotion. Activity monitors have evolved from step counters and measuring devices of physical activity duration and intensity to more advanced systems providing quantitative and qualitative information on the individuals' activity behavior. Correspondingly, methods to predict activity-related energy expenditure using bodily acceleration and subjects characteristics have advanced from linear regression to innovative algorithms capable of determining physical activity types and the related metabolic costs. These novel techniques can monitor modes of sedentary behavior as well as the engagement in specific activity types that helps to evaluate the effectiveness of lifestyle interventions. In conclusion, advances in activity monitoring have the potential to support the design of response-dependent physical activity recommendations that are needed to generate effective and personalized lifestyle interventions for health promotion.

Daily walking activity among male office workers in a rural town in northern Japan

To investigate the level of walking activity among residents of the Tohoku district in northern Japan, where no widespread public transport system has been developed, winter is severe. The participants were 50 town hall employees with an average age of 43.6+/-10.8 (SD) years. The walking activity of each participant was assessed using a pedometer for one week in summer and one week in winter. The participants' lifestyles, including their commuting methods, were assessed using a questionnaire. Forty-six participants (92%) usually commute to work by private car. The average numbers of steps/day on workdays and holidays were, in summer, 6,560+/-2,600 and 7,016+/-4,679, respectively, and, in winter, 5,236+/-2,253 and 4,770+/-3,039; these numbers were somewhat lower than those recorded in previous reports. We observed a significant reduction in walking during winter (F=19.016, p=0.0001), but no significant differences between workdays and holidays (F=0.001, p=0.966). A significant correlation between BMI and steps/day (r=-0.420, p<0.01) was obtained on workdays in winter. The unexpectedly low level of these participants' physical activity, especially in winter, is probably due to the fact that most of them commute by private car, which is likely a cause of the high incidence of obesity in this district. In addition, a seasonal effect should also be considered when physical activity is assessed, especially in cold climates.

How many days are enough? A study of 365 days of pedometer monitoring

This study was designed to determine the number of days of pedometer monitoring necessary to achieve reliable and valid estimates of a 1-year average of step counts in adults based on either consecutive days (CD) or random days (RD) of data collection. Twenty-three participants (16 women; M age = 38 years, SD = 9.9) wore a Yamax SW 200 pedometer and recorded their step counts for 365 consecutive days. Nine measurement periods of various lengths were selected (2, 3, 4, 5, 6, 7, 14, 21, and 30 days). Each measurement period was randomly selected 10 times each for CD and RD from the larger database. For reliability and validity, two-way intraclass correlation coefficients and mean absolute percentage error (MAPE) were calculated, respectively. The year-round average was considered the criterion measure of the "true" habitual physical activity. Data were analyzed separately by CD and RD. At least 5 CD or 6 RD were necessary to achieve an ICC of .80. A minimum of 30 CD or 14 RD were necessary to achieve an MAPE lower than 10%. These findings provide researchers and practitioners with useful information to determine appropriate measurement length and the method of data selection based on a desired level of reliability and validity.

Increasing our understanding of reactivity to pedometers in adults

PURPOSE

To investigate the presence of reactivity, if any, to wearing sealed and unsealed pedometers, with and without step count recording.

METHODS

On the first visit to the laboratory, 63 participants (41 females and 22 males; age = 23.6 +/- 9.6 yr, body mass index = 22.7 +/- 3.0 kg x m(-2)), blinded to the study aim, were provided with a sealed pedometer (New Lifestyles NL-1000) and informed that it was a "body posture monitor" (covert monitoring). Participants wore the pedometer throughout waking hours for 1 wk. On return to the laboratory, stored step counts were downloaded, and participants were informed that the device was a pedometer. Participants wore the pedometer under three more conditions-sealed, unsealed, and unsealed plus logging daily steps in an activity diary-each having a duration of 1 wk. The order of participation in each condition (sealed/unsealed/diary) was balanced across participants. Mean daily step counts recorded during the four conditions were compared using a repeated-measures ANOVA.

RESULTS

There was a significant overall effect of condition (P < 0.001; covert monitoring = 8362 +/- 2600 steps per day; sealed condition = 8832 +/- 2845 steps per day; unsealed condition = 9176 +/- 3299 steps per day; diary condition = 9635 +/- 2709 steps per day), with post hoc analyses revealing that mean step counts were significantly higher in the diary condition than those reported during both the covert and sealed conditions (both P < 0.003). No significant gender effects were observed (P = 0.33).

CONCLUSION

The greatest increase in step counts occurred in the diary condition, suggesting that reactivity to pedometers is greatest when participants are requested to wear an unsealed pedometer and record their step counts. This has validity implications for short-term pedometer studies investigating habitual free-living activity that require participants to provide a daily log of their step counts.

Pedometer-determined physical activity and indicators of health in Japanese adults

Recently, many cross-sectional studies observed that body mass index (BMI) and percentage of body fat (%BF) were inversely associated with pedometer-determined physical activities, but studies on Asian populations, including the Japanese, are sparse. Height, weight, body fat percentage (%BF, bioelectrical impedance analyzer), and waist circumference were measured on 117 women (62.8+/-4.5 years, 22.2+/-2.2 kg/m(2)) and 62 men (64.0+/-4.6 years, 23.6+/-2.5 kg/m(2)). Pearson correlations and partial correlation coefficients after controlling for age were calculated between steps/day and variables. Furthermore, participants were classified into four groups as follows: <5,000, 5,000-7,499, 7,500-9,999, and >or=10,000 steps/day, and analyzed using ANOVA across activity groups. In women, a significant correlation was found between steps/day and BMI (r=-0.217, p=0.018), %BF (r=-0.292, p=0.0014), and the relationship was still significant after controlling for age. The relationship between steps/day and waist circumference was not significant. In men, a significant relationship was not observed between steps/day and obesity indices. The correlations between steps/day and both BMI and %BF were significant in Japanese women, but weak compared with Caucasian and African-American women as reported previously. A possible cause is racial difference in degree of obesity and body shape. The effects of physical activity on body shape and composition may differ according to race.

Rationale, design and baseline data from the Pre-diabetes Risk Education and Physical Activity Recommendation and Encouragement (PREPARE) programme study: a randomized controlled trial

OBJECTIVE

The PREPARE programme study is a randomized controlled trial which aims to determine whether structured education can be used to increase physical activity and improve glucose tolerance in individuals with impaired glucose tolerance (IGT). This paper outlines the rationale, design and baseline data from the PREPARE programme study.

METHODS

Individuals with IGT were recruited from ongoing diabetes screening programmes. Outcomes included an oral glucose tolerance test, physical activity (piezoelectric pedometer) and psychological determinants.

RESULTS

103 individuals (male n = 65; female n = 38) were recruited, 28% of whom were from a South Asian ethnic background. At baseline the participants' mean age and BMI were 64 +/- 9 years and 29.4 +/- 4.5 kg/m2 respectively. Steps per day were associated with 2-h glucose (p = -0.22, p = 0.03), fasting glucose (p = 0.22, p = 0.04), HDL-cholesterol (p = 0.23, p = 0.02), triglycerides (p = -0.22, p = 0.03) and body fat percentage (p = -0.26, p = 0.01). Mean self-efficacy scores were significantly (p < 0.01) higher for walking than for any other form of exercise. Participants reported high levels of concern about their IGT status but were confident that exercise would help treat/control IGT.

CONCLUSION

This study demonstrates the importance of developing effective physical activity and self-management programmes for individuals with IGT.

PRACTICE IMPLICATIONS

This study provides a detailed framework for the promotion of physical activity in a population identified with an increased risk of developing type 2 diabetes which, if successful, could feasibly be implemented in a primary health care or community setting.

Influence of weekend lifestyle patterns on body weight

OBJECTIVE

To determine whether alterations in diet and/or activity patterns during weekends contribute to weight gain or hinder weight loss.

METHODS AND PROCEDURES

Randomized, controlled trial comparing 1 year of caloric restriction (CR) with 1 year of daily exercise (EX). Subjects included 48 healthy adults (30F, 18M) aged 50-60 years with BMI 23.5-29.9 kg/m(2). Body weight was measured on 7 consecutive mornings for a total of 165 weeks at baseline and 437 weeks during the 1-year interventions. Daily weight changes were calculated for weekends (Friday to Monday) and weekdays (Monday to Friday). Daily energy intake was estimated using food diaries; daily physical activity was measured using accelerometers. Both measures were validated against doubly labeled water (DLW).

RESULTS

At baseline, participants consistently gained weight on weekend days (+0.06 +/- 0.03 kg/day, (mean +/- s.e.), P = 0.02), but not on weekdays (-0.02 +/- 0.02 kg/day, P = 0.18). This was attributable to higher dietary intake on Saturdays and lower physical activity on Sundays relative to weekdays (both P < 0.05). During the interventions, both CR and EX participants were in negative energy balance on weekdays (P < 0.005). On weekends, however, CR participants stopped losing weight, and EX participants gained weight (+0.08 +/- 0.03 kg/day, P < 0.0001) due to higher dietary intakes on weekends. This helps to explain the slower-than-expected rate of weight loss during the interventions.

DISCUSSION

Alterations in lifestyle behaviors on weekends contribute to weight gain or cessation of weight loss on weekends. These results provide one explanation for the relatively slow rates of weight loss observed in many studies, and the difficulty with maintaining significant weight loss.

UK adults exhibit higher step counts in summer compared to winter months

BACKGROUND

Seasonal differences in step counts have been observed in a limited number of studies conducted on US adults. Due to the diverse global climate, assessment and interpretation of seasonal patterns in ambulatory activity may vary between countries, and regionally specific studies are necessary to understand global patterns. Currently, no studies have assessed whether a seasonal trend is present when ambulatory activity is measured objectively in adults living in the UK.

AIM

The present study investigated whether pedometer-determined step counts of adults living in the UK vary between summer and winter.

SUBJECTS AND METHODS

Ninety-six adults (52% male, age = 41.0 +/- 12.3 years, BMI = 26.1 +/- 5.1 kg m(-2)) completed a within-subject bi-seasonal pedometer study. All participants completed two 4-week monitoring periods; one during the summer and one the following winter. The same Yamax SW-200 pedometer was worn throughout waking hours during both seasons, and daily step counts were recorded in an activity log. Intra-individual seasonal changes in mean daily steps were analysed using a paired samples t-test.

RESULTS

Summer mean daily step counts (10 417 +/- 3055 steps day(-1)) were significantly higher than those reported during the winter (9132 +/- 2841 steps day(-1)) (p < 0.001). A follow-up study conducted the subsequent summer in a sub-sample (n = 28) reinforced this trend. Summer step counts were significantly higher than winter step counts on all days of the week (p < or = 0.001). A significant day of the week effect was present in both seasons, with step counts reported on a Sunday being on average 1500 steps day(-1) lower than those reported Monday through to Saturday.

CONCLUSION

Step counts in the sample of UK adults surveyed decreased significantly in the winter compared to the summer, suggesting future pedometer surveillance studies should capture step counts throughout the year for a non-biased reflection of habitual ambulatory activity. Public health initiatives should target these seasonal differences, and opportunities should be provided that encourage individuals to increase their activity levels during the colder, darker months of the year.

Four-week pedometer-determined activity patterns in normal-weight, overweight and obese adults

OBJECTIVE

To assess pedometer-determined ambulatory activity in normal-weight, overweight and obese UK adults.

METHODS

Eighty-six normal-weight (BMI <25 kg/m(2)) (age=34+/-12.1 years), 91 overweight (BMI 25-29.9 kg/m(2)) (age=40.6+/-13.6 years) and 75 obese (BMI >or= 30 kg/m(2)) (age=41.2+/-12.4 years) participants, from the East Midlands, provided 4 weeks of continuous pedometer-determined activity data, during the winter in 2006. Activity levels and patterns were assessed for all three groups.

RESULTS

The normal-weight group had a significantly higher mean step count (10247 steps/day) than the overweight (9095 steps/day) and obese (8102 steps/day) participants (p<0.05). No differences in step counts were observed between the overweight and obese groups. A consistent reduction in activity was observed on Sundays in all groups, with this reduction being two-fold greater in the overweight and obese groups (approximately 2000 steps/day) when compared with the normal-weight group (approximately 1000 steps/day).

CONCLUSIONS

With the increasing prevalence of obesity in the UK, changes in the activity levels of those at risk are needed. The issuing of pedometers to overweight and obese individuals, with the instruction to increase their ambulatory activity on all days of the week, with particular emphasis on Sunday activity, could be a good starting point in tackling the problem of obesity in the UK.

Effects of "10,000 steps Ghent": a whole-community intervention

BACKGROUND

Currently there is a great deal of interest in multistrategy community-based approaches to changing physical activity or health behaviors. The aim of this article is to describe the effectiveness of the physical activity promotion project "10,000 Steps Ghent" after 1 year of intervention.

METHODS

A multistrategy community-based intervention was implemented in 2005 with follow-up measurements in 2006 to promote physical activity to adults. A local media campaign, environmental approaches, the sale and loan of pedometers, and several local physical activity projects were concurrently implemented. In 2005, 872 randomly selected subjects (aged 25 to 75), from the intervention community Ghent and 810 from a comparison community, participated in the baseline measurements. Of these, 660 intervention subjects and 634 comparison subjects completed the follow-up measurements in 2006. Statistical analyses were performed in 2006.

RESULTS

After one year there was an increase of 8% in the number of people reaching the "10,000 steps" standard in Ghent, compared with no increase in the comparison community. Average daily steps increased by 896 (95% CI=599-1192) in the intervention community, but there was no increase in the comparison community (mean change -135 [95% CI= -432 to 162]) (F time x community=22.8, p<0.001). Results are supported by self-reported International Physical Activity Questionnaire (IPAQ) data.

CONCLUSIONS

The "10,000 steps/day" message reached the Ghent population and the project succeeded in increasing pedometer-determined physical activity levels in Ghent, after 1 year of intervention.