Brandon Caitlin A, Gill Dawn P, Speechley Mark, Gilliland Jason, Jones Gareth R
Brandon, Health and Rehabilitation Sciences, University of Western Ontario, Elborn College, London, ON N6G1H1, Canada.
Appl Physiol Nutr Metab. 2009 Apr;34(2):182-90. doi: 10.1139/H09-004.
Adequate daily physical activity (PA) is important for maintaining functional capacity and independence in older adults. However, most older adults in Canada do not engage in enough PA to sustain fitness and functional independence. Environmental influences, such as warmer daytime temperatures, may influence PA participation; however, few studies have examined the effect of summertime temperatures on PA levels in older adults. This investigation measured the influence of summertime weather variables on PA in 48 community-dwelling older adults who were randomly recruited from a local seniors' community centre. Each participant wore an accelerometer for a single 7-consecutive-day period (between 30 May and 9 August 2006) during waking hours, and completed a PA logbook to remark on major daily PA events. Local weather variables were collected from a national weather service and compared with PA counts per minute. Regression analysis revealed a curvilinear relationship between log-transformed PA and mean daily temperature (r2 = 0.025; p < 0.05). Linear mixed effects models that accounted for repeated measures nested within individuals were performed for monthly periods, meteorological variables, sex, age, and estimated maximal oxygen consumption, with PA as the dependent variable. Age and Air Quality Index remained significant variables within the model. Higher fitness levels had no effect on allowing individuals to perform more vigorous PA in warmer temperatures.
充足的日常身体活动(PA)对于维持老年人的功能能力和独立性很重要。然而,加拿大的大多数老年人没有进行足够的身体活动来维持健康和功能独立。环境因素,如白天温度较高,可能会影响身体活动的参与;然而,很少有研究探讨夏季温度对老年人身体活动水平的影响。这项调查测量了夏季天气变量对48名从当地老年人社区中心随机招募的社区居住老年人身体活动的影响。每位参与者在清醒时间佩戴加速度计连续7天(2006年5月30日至8月9日之间),并完成一份身体活动日志,记录主要的日常身体活动事件。从国家气象局收集当地天气变量,并与每分钟的身体活动计数进行比较。回归分析显示,经对数转换的身体活动与日平均温度之间存在曲线关系(r2 = 0.025;p < 0.05)。以身体活动为因变量,对每月时间段、气象变量、性别、年龄和估计的最大耗氧量进行了考虑个体内重复测量的线性混合效应模型分析。年龄和空气质量指数在模型中仍然是显著变量。较高的健康水平对个体在较温暖温度下进行更剧烈的身体活动没有影响。