School of Health and Sport Science, Juntendo University, Chiba, Japan.
Gait Posture. 2011 Jun;34(2):292-4. doi: 10.1016/j.gaitpost.2011.04.015. Epub 2011 Jun 12.
The minute-by-minute stepping rate (MMSR) is a unique index of the walking speed. The MMSR under free-living conditions remains unclear.
The purpose of the present investigation was to clarify the physical activity (PA) levels based on MMSR under free-living conditions.
A total of 85 female volunteers, age from 21 to 91 year, wore a pedometer with a uni-axial accelerometer (Lifecorder, Kenz, Japan) for 7 days consecutively in order to determine the number of steps, the intensity of PA (light intensity PA; LPA, moderate intensity PA; MPA, and vigorous intensity PA; VPA), and the MMSR. Thereafter, the daily time spent in PA at <100, 100 to 129, and 130 steps min(-1) (min day(-1)) was calculated. All experiments were conducted in March 2007.
The number of steps, the time spent in LPA, MPA, VPA, PA at <100, 100 to 129, and 130 steps min(-1) were 9275±3453 steps day(-1), 71±25 min day(-1), 34±22 min day(-1), 4±6 min day(-1), 295±88 min day(-1), 16±12 min day(-1), and 4±6 min day(-1). The time spent in PA at <100 steps min(-1) positively associated with age (p<0.05). The time spent in PA at 100 to 129 steps min(-1) negatively associated with age (p<0.01).
The time spent in PA at <130 of steps min(-1) MMSR differs across different age-groups under free-living conditions in female adults. The clinical significance with regards to the age-associated changes in MMSR remains unclear.
每分钟步数（MMSR）是步行速度的一个独特指标。但在自由生活条件下，MMSR 仍不清楚。
本研究旨在阐明在自由生活条件下基于 MMSR 的身体活动（PA）水平。
共有 85 名年龄在 21 至 91 岁的女性志愿者连续佩戴带有单轴加速度计的计步器（Lifecorder，Kenz，日本）7 天，以确定步数、PA 强度（低强度 PA；LPA、中强度 PA；MPA 和高强度 PA；VPA）和 MMSR。此后，计算每天在 <100、100 至 129 和 130 步 min(-1)（min 天(-1)）的 PA 时间。所有实验均于 2007 年 3 月进行。
步数、LPA、MPA、VPA、<100 步 min(-1)、100 至 129 步 min(-1)和 130 步 min(-1)的 PA 时间分别为 9275±3453 步天(-1)、71±25 min 天(-1)、34±22 min 天(-1)、4±6 min 天(-1)、295±88 min 天(-1)、16±12 min 天(-1)和 4±6 min 天(-1)。<100 步 min(-1)的 PA 时间与年龄呈正相关（p<0.05）。100 至 129 步 min(-1)的 PA 时间与年龄呈负相关（p<0.01）。
在女性成年人的自由生活条件下，不同年龄组的 <130 步 min(-1)的 MMSR 所花费的 PA 时间不同。年龄相关的 MMSR 变化的临床意义尚不清楚。
