Acquiring a stable estimate of physical activity in adults with visual impairment.

As a first step toward the development of adapted physical activity (PA) programs for adults with visual impairment (VI), the purpose of this study was to determine the time frame needed to reliably estimate weekly PA in adults with VI. Thirty-three adults with VI completed 7 days of pedometer-based PA assessment. Generalizability theory analyses were conducted to quantify sources of variance within the PA estimate and determine the appropriate number of days of PA monitoring needed for the total sample and for participants with mild-to-moderate and severe VI. A single-facet, crossed design was employed including participants and days. Participants and days correspondingly accounted for 33-55% and 0-3% of the total variance in PA. While a reliable account of PA was obtained for the total sample over a 6-day period, shorter (4-day) and longer (9-day) periods were required for persons with mild-to-moderate and severe VI, respectively.

Evaluation of inactive adults' ability to maintain a moderate-intensity walking pace.

OBJECTIVES: To determine self-selected brisk walking pace in currently inactive adults and investigate the efficacy of rhythmic auditory stimuli to regulate moderate intensity walking. DESIGN: A single-sample controlled laboratory design. METHODS: Currently inactive adults (N=25; 76% female; age=34±13yr) completed a moderate intensity treadmill walking trial, during which cadence and steady-state O2 were measured. Participants then completed a 10-min self-paced "brisk" walk followed by a 10-min moderate-paced walk, prompted by a clip-on metronome matched to the treadmill cadence. Data were analyzed using RM t-test, Cohen's d, Bland-Altman plot, and one-way RM ANOVA. RESULTS: Mean energy expenditure and cadence during the treadmill trial were 3.88±0.53METs and 114±8stepsmin(-1). During self-paced brisk walking cadence was 124±8stepsmin(-1). Cadence during metronome-paced walking was slower for all participants (114±8stepsmin(-1); p<0.05, d=1.23). From the Bland-Altman plots, 23 participants walked within ±3stepsmin(-1) of the metronome cadence, and the other 2 participants were within ±10stepsmin(-1). There were no significant differences (p>0.05) among the minute-by-minute cadences across the 10min of either condition. CONCLUSIONS: Energy expenditure during 2.7mph treadmill walking was higher than 3 METs. Inactive adults walk at a higher cadence during "brisk" walking, compared to walking at a metronome-guided moderate pace. While the natural walking pace of inactive adults was at an intensity known to produce health benefits, and was maintained for 10min, the use of rhythmic auditory feedback is an effective method for regulating walking at a prescribed intensity in inactive adults.

Influence of age on step activity patterns in children with cerebral palsy and typically developing children.

OBJECTIVE: To document the influence of age on step activity patterns in children with cerebral palsy (CP) and typically developing (TD) children. DESIGN: Cross-sectional. SETTING: All step activity data were collected in free-living environments. PARTICIPANTS: Children with CP (n=27; age, 4-18y; 22 boys, 5 girls; Gross Motor Function Classification System levels I and II) and 27 age- and sex-matched TD children were recruited through public advertisements and contacts with local clinicians. CP and TD participants were stratified into younger (<10y; n=14) and older (10-18y; n=13) age groups. INTERVENTION: Daily step activity was monitored using a step activity monitor that was individually programmed to account for the gait characteristics of each participant. Step activity data were collected in 1-minute epochs during waking hours on 3 weekdays and 1 weekend day. Stored data were analyzed to yield average values of daily step activity, percentage of inactive time (0 steps) over the entire day, and percentage of total daily active time spent in low step activity (1-15 steps/min), medium step activity (16-40 steps/min), and high step activity (>40 steps/min). MAIN OUTCOME MEASURES: Daily step activity, percentage of inactive time, and percentage of active time spent in low-, moderate-, and high-intensity step activity. RESULTS: A significant (P<.05) interaction was observed between age (younger, older) and condition (CP, TD) for daily step activity, percentage of inactive time, and percentage of active time spent in low- and high-intensity step activity. The main effect of age was significant for each physical activity measure except for relative high-intensity step activity, and the main effect of condition was significant for all physical activity measures. Follow-up analyses (P<.025) revealed that older children with CP took fewer daily steps and displayed higher relative levels of inactivity and low-intensity activity and lower relative levels of high-intensity activity compared with older TD children. Older children with CP also exhibited lower daily step activity, demonstrated higher relative levels of inactivity and low-intensity activity, and displayed lower relative levels of moderate-intensity activity compared with younger children with CP. CONCLUSIONS: Compared with younger children with CP and age- and sex-matched TD youth, older youth with CP generally displayed step activity patterns typified by lower levels of physical activity and a greater degree of inactivity. These findings highlight the need to provide multiple opportunities for adolescents with CP to engage in a variety of physical activities that are appropriate to their needs, abilities, and preferences and that can aid in maintaining functional mobility, health, and quality of life.

Validity and reliability of Omron pedometers for prescribed and self-paced walking.

PURPOSE: The purpose of this study was to examine the validity and reliability evidence for the Omron Healthcare HJ-151 and HJ-720ITC pedometers for prescribed and self-paced walking. METHODS: A total of 47 adults (24 males, 23 females; age = 24 +/- 4.4 yr.; body mass index = 25.7 +/- 4.2 kg x m(-2)) participated in this study. Under prescribed walking conditions, 34 participants completed three randomized 100-m walking trials through a range of scripted walking speeds (slow, moderate, and very brisk) for each pedometer model. Under self-paced walking conditions, 31 participants completed one 1-mile walk on a standardized course for each model. HJ-151 pedometers were chosen at random from a pool of 54 devices and were worn along the waistband at the right hip, the left hip, and the midback, whereas HJ-720ITC pedometers were chosen from a pool of 24 devices and incorporated right pocket, left pocket, and backpack positions in addition to the three waist-mounted sites. Absolute percent error (APE) scores were calculated to examine pedometer accuracy between actual steps (a criterion measure) and pedometer-determined steps. Coefficient of variation (CoV) was computed to describe interdevice reliability. RESULTS: With the exception of the HJ-720ITC at the backpack position in the prescribed walking setting (mean APE = 3.4%), the HJ-151 and the HJ-720ITC accurately reported step counts under prescribed and self-paced conditions (all APE values <3.0%). Moreover, interdevice reliability evidence was established for the HJ-151 and the HJ-720ITC under prescribed and self-paced conditions (all CoV values <2.1%). CONCLUSIONS: The Omron HJ-151 and HJ-720ITC pedometers demonstrated validity and reliability at various mounting positions under prescribed and self-paced walking conditions with both healthy and overweight adults.