This exploratory study examined the feasibility of using Garmin global positioning system (GPS) watches and ActiGraph accelerometers to monitor walking and other aspects of community mobility in older adults. After accuracy at slow walking speeds was initially determined, 20 older adults (74.4 ± 4.2 yr) wore the devices for 1 day. Steps, distances, and speeds (on foot and in vehicle) were determined. GPS data acquisition varied from 43 min to over 12 hr, with 55% of participants having more than 8 hr between initial and final data-collection points. When GPS data were acquired without interruptions, detailed mobility information was obtained regarding the timing, distances covered, and speeds reached during trips away from home. Although GPS and accelerometry technology offer promise for monitoring community mobility patterns, new GPS solutions are required that allow for data collection over an extended period of time between indoor and outdoor environments.
Sandra C. Webber and Michelle M. Porter
James B. Dear, Michelle M. Porter and A. Elizabeth Ready
This study compared the intensity and energy cost of playing 9 holes of golf with 40 min of lawn mowing in older men and determined whether both met the current recommendations for health benefits. Eighteen men (age 71.2 ± 4.4 yr, BMI 27.3 ± 2.3; M ± SD) completed a graded treadmill test. During golfing and lawn-mowing field tests, oxygen consumption and walking velocity and distance were measured using a portable metabolic system and global positioning system receiver. The net energy costs of golfing and lawn mowing were 310 and 246 kcal, respectively. The average intensities in metabolic equivalents of golfing and lawn mowing were 2.8 ± 0.5 and 5.5 ± 0.9, respectively. Both lawn mowing and golfing met the original intensity and energy expenditure requirements for health benefits specified by the American College of Sports Medicine in 1998, but only lawn mowing met the 2007 intensity recommendations.
Lucelia Luna de Melo, Verena Menec, Michelle M. Porter and A. Elizabeth Ready
This study examined the associations between walking behavior and the perceived environment and personal factors among older adults. Sixty participants age 65 yr or older (mean 77 ± 7.27, range 65–92) wore pedometers for 3 consecutive days. Perceived environment was assessed using the Neighborhood Environment Walk-ability Scale (abbreviated version). Physical function was measured using the timed chair-stands test. The mean number of steps per day was 5,289 steps (SD = 4,029). Regression analyses showed a significant association between personal factors, including physical function (relative rate = 1.05, p < .01) and income (RR = 1.43, p < .05) and the average daily number of steps taken. In terms of perceived environment, only access to services was significantly related to walking at the univariate level, an association that remained marginally significant when controlling for personal characteristics. These results suggest that among this sample of older adults, walking behavior was more related to personal and intrinsic physical capabilities than to the perceived environment.
Michelle M. Porter, Miriam E. Nelson, Maria A. Fiatarone Singh, Jennifer E. Layne, Christine M. Morganti, Isaiah Trice, Christina D. Economos, Ronenn Roubenoff and William J. Evans
Resistance training (RT) increases strength in older adults, but there have been few studies of long-term RT or detraining in older adults. Postmenopausal participants (51–71 years of age) were randomized to RT or a control group for Year 1. For Year 2, participants chose whether to resistance train or not. Three groups emerged: train/train (n = 8: 60 ± 4 years), train/no train (n = 11: 62 ± 3 years), or controls (n = 17; 58 ± 6 years). Both training groups increased strength (p < .05) in Year 1. In Year 2, train/train maintained strength, whereas train/no train lost strength for knee extension (p < .001) but not for arm pulldown. Controls did not change. Reported physical activity levels were significantly increased in trainers in Year 1 and remained high regardless of RT in Year 2 (p < .05). Therefore, sustained changes in strength and physical activity behavior might be possible even if RT is discontinued.