Walking is one of the most common forms of human locomotion. The development of objective monitoring devices (e.g., pedometers or accelerometers) has afforded public health researchers a unique opportunity to measure ambulatory behavior, including walking, with minimal bias. Objective monitors have been used in a number of cross-sectional national- and state-representative studies to assess walking behavior. Data from these studies, and smaller investigations, have allowed researchers to assess the relationships between total daily ambulation (steps/day) and various health indicators. The growing body of investigations measuring ambulatory behavior has also prompted researchers to seek answers to related questions: “how many steps/day are too few?” and “how many steps/day are enough?” Moreover, recent epidemiological evidence has linked ambulatory speed (steps/min) to various health outcomes and has peaked researchers’ interests in answering “how fast is enough?” This brief review: 1) summarizes current epidemiological literature examining objectively monitored ambulatory behavior, 2) answers public health relevant questions concerning insufficient and sufficient amounts of daily walking, 3) considers the relative importance of walking speed in relation to public health, and 4)identifies future research directions related to the assessment of walking behavior.

Environmental strategies to influence physical activity are considered effective for large populations, as supportive environments are likely to assist many people to be active for long periods. Ecological models - that recognise the importance of multiple influences on physical activity, including individual, socialand environmental factors - provide theoretical underpinnings for research on environmental attributes. This commentary reflects upon past research in this area, and proposes an extended ecological model, in which physical activity is divided into adoption and maintenance. It is postulated that individual and social factors may help people to initiate physical activity, while environmental factors may be more relevant to the maintenance of physical activity. Future studies need to examine the roles of individual, social and environmental factors in bringing about wide-reaching and sustained changes in physical activity.

Falls are relatively common in the elderly, with approximately 30% of individuals aged 65 and older falling at least once a year and approximately half of them experiencing repeated falls. Falls and fractures have a major impact on elderly individuals, their caregivers, health service providers, and the community. Recent systematic review suggested that falls can be prevented by well-designed exercise programs that target balance and involve a good amount of exercise. On the other hand, in daily life, locomotion occurs under complicated circumstances, with cognitive attention focused on a particular task, such as watching the traffic or reading street signs, rather than on performing a simple motor task such as walking. A seminal study demonstrating that the characteristic “stops walking when talking” could serve as a predictor of falls introduced a novel method for predicting falls based on dual-task performance. Recent study indicated that different factors may be related to fall incidents depending on the level of frailty of the community-dwelling elderly adults. These findings suggest that fall prevention programs should be tailored to the elderly adult’s level of physical well-being. The purpose of this review is to review approaches to fall prevention tailored to an individual’s level of physical well-being.

Objective: The purpose of the present study was to examine the influence of turf playground on children’s physical activity during recess.

Methods: The participants were fifty boys and thirty six girls from the grade 3 to 6 of primary school. Their physical activity was examined using accelerometry before and after implementation of turf playground (about 2500 m² on the inside of the track) for seven consecutive days respectively. Time spent in sedentary, light, moderate, and vigorous physical activity during 25 minutes break and 15 minutes lunch recess was evaluated. Repeated measures analysis of covariance, with grade as the covariate, was used to examine differences in physical activity between pre-and post-implementation of turf playground.

Results: Data of fifty five children (35 boys) during break and fifty six children (35 boys) during lunch recess were available for analyses. During break, girl’s moderate physical activity significantly increased after implementation of turf playground (from 1.3 ± 0.7 to 1.6 ± 0.7; p = 0.04). However, children’s sedentary time significantly increased (boys: from 3.6 ± 2.7 to 6.8 ± 3.1; p < 0.001, girls: from 3.9 ± 2.3 to 7.5 ± 2.4; p = 0.02) and light physical activity significantly decreased (boys: from 9.0 ± 2.7 to 5.6 ± 2.1; p = 0.01, girls: from 9.5 ± 2.4 to 6.6 ± 1.9; p = 0.01) during lunch recess.

Conclusion: Turf playground had an influence on physical activity increased in girls during break, although decreased physical activity in both gender during lunch recess. It is needed to examine qualitative change of physical activity by observation and to develop approaches which improve the effectiveness of turf playground on recess physical activity among children.

Objective: Accelerometers are objective and valid tools that have been used extensively to monitor activity patterns in field settings to assess free-living physical activity. However, several data processing issues may produce differences in outcome measures of physical activity. This study examined the effects of epoch length on outcome measures of locomotive and non-locomotive activity by using a triaxial accelerometer Active Style Pro (Omron Healthcare, Kyoto, Japan).

Methods: The participants were 213 overweight adults who were recruited for a weight-loss intervention study. The data from 209 of them were considered valid and were analyzed. The participants wore the accelerometers for 14 consecutive days for the assessment of baseline physical activity. A valid day was defined as having 10 hours or more of wear time. Total daily minutes of locomotive and non-locomotive activity were evaluated if there were valid records for more than 2 weekdays and 1 day on the weekend. Outcome measures of physical activity were compared between the epoch lengths 10 seconds and 60 seconds.

Results: Total daily minutes of moderate-to-vigorous (≥ 3 METs) locomotive and non-locomotive activities were lower in epoch length of 60 seconds compared with that of 10 seconds. Total daily minutes of sedentary-to-light (< 3 METs) locomotive activity was lower and those of non-locomotive activity was higher in an epoch length of 60 seconds compared with that of 10 seconds. Effect sizes (Cohen’s d) of moderate-to-vigorous and sedentary-to-light non-locomotive activity (2.81 and 3.33, respectively) were larger than those of locomotive activity (1.43 and 0.30, respectively).

Conclusion: These findings suggest that the choice of epoch length affects outcome measures of physical activity and that this effect is more apparent in non-locomotive activity than in locomotive activity.