Pillay Julian David, Kolbe-Alexander Tracy Lynn, van Mechelen Willem, Lambert Estelle Victoria
Dept of Basic Medical Sciences, Durban University of Technology, Durban, KwaZulu Natal, South Africa.
J Phys Act Health. 2014 Jan;11(1):10-7. doi: 10.1123/jpah.2011-0288. Epub 2012 Dec 17.
Pedometer-based recommendations for accumulating steps/d largely focus on volume, with less emphasis on intensity and fitness/health outcomes. We aim to examine this relationship.
A convenience sample (N = 70, 35 men, 32 ± 8yrs) wore a pedometer (4 days). The pedometer classified steps as "aerobic" (≥ 60 steps/minute, minimum duration of 1 minute) or "non-aerobic" (< 60 steps/minute and/or < 1 minute). Estimated maximal oxygen uptake (VO2max), derived from a 12-minute submaximal step-test, and health outcomes: blood pressure (BP), body mass index (BMI), percentage body fat (%BF), and waist circumference (WC) were correlated with pedometer data. Participants were grouped according to number and intensity of steps: LOW (< 5000 steps/d), HIGH-LOW (≥ 5000 steps/d, no aerobic steps), HIGH-HIGH (≥ 5000 steps/d, including some aerobic steps). Analyses of covariance, adjusting for age, gender, and total steps/d were used to compare groups.
Average steps/d was 6520 ± 2306. Total steps/d and total time spent accumulating "aerobic" steps (minutes/day) were inversely associated with %BF, BMI, WC, and systolic BP (P < .05). After adjusting for gender and total steps/d, %BF was different between all 3 groups, VO2max was different between the LOW and HIGH-HIGH groups, WC was lower in the HIGH-HIGH versus the other 2 groups (P < .03, respectively).
Intensity seems an important factor to consider in steps/d cut-points.
基于计步器的每日步数积累建议主要侧重于步数总量,而对强度以及健康/健身结果的关注较少。我们旨在研究这种关系。
选取一个便利样本(N = 70,35名男性,年龄32±8岁)佩戴计步器4天。计步器将步数分为“有氧运动”(≥60步/分钟,最短持续时间1分钟)或“非有氧运动”(<60步/分钟和/或<1分钟)。通过12分钟次极量踏阶试验得出的估计最大摄氧量(VO2max)以及健康指标:血压(BP)、体重指数(BMI)、体脂百分比(%BF)和腰围(WC)与计步器数据进行相关性分析。参与者根据步数数量和强度进行分组:低步数组(<5000步/天)、低高强度组(≥5000步/天,无有氧运动步数)、高高强度组(≥5000步/天,包括一些有氧运动步数)。采用协方差分析,并对年龄、性别和每日总步数进行校正,以比较各组之间的差异。
平均每日步数为6520±2306。每日总步数以及积累“有氧运动”步数所花费的总时间(分钟/天)与%BF、BMI、WC和收缩压呈负相关(P<.05)。在对性别和每日总步数进行校正后,所有3组之间的%BF存在差异,低步数组和高高强度组之间的VO2max存在差异,高高强度组的WC低于其他2组(P分别<.03)。
在确定每日步数阈值时,强度似乎是一个需要考虑的重要因素。