Faculty of Sport and Health Sciences and Gerontology Research Center, University of Jyväskylä, P.O. Box 35 (viv 289), 40014, Jyvaskyla, Finland.
Institute for Physical Activity and Nutrition (IPAN), School of Exercise and Nutrition Sciences, Deakin University, Geelong, Australia.
Eur J Appl Physiol. 2021 Sep;121(9):2563-2571. doi: 10.1007/s00421-021-04731-3. Epub 2021 Jun 5.
Detailed exploration of physical activity accumulation with fine grading along the intensity spectrum has indicated the potential pragmatic utility of such an approach. However, it is currently unclear what sorts of accumulation patterns along particular intensity bands are found in the children and adult populations. Therefore, we conducted a comparison of activity accumulation in specific intensity bands between four distinct populations: children, adults with sedentary lifestyles, habitual joggers, habitual marathon runners.
Free-living waist-worn accelerometry records from 28 children aged 7 to 11, and 61 adults aged 25 to 35 were analysed. Activity intensity was evaluated in 5 s non-overlapping epochs as mean amplitude deviation (MAD) and normalised to acceleration intensities corresponding to walking at 3 metabolic equivalents of a task (METs). Adult data were normalised to 0.091 g MAD based on literature, and data from children to 0.170 g MAD based on laboratory experimentation. The normalised epoch values were divided into 100 intensity gradations.
Children accumulated more activity in 0.74 to 1.58 normalised acceleration intensities (all p < 0.005) compared to adults. Adult joggers/runners accumulated more activity in normalised acceleration intensities from 7.1 to 11.1 compared to the other groups (p < 0.008).
The primary bulk of children's free-living activities are of relatively low intensity not likely to provoke cardiometabolic improvement. These sorts of explorations could be used in informing intervention development aiming at optimising healthy development. Evidence is mounting to justify randomised controlled trials based on intervention targets identified based on exploring the intensity spectrum.
详细探索沿着强度谱进行精细分级的身体活动积累，表明了这种方法具有潜在的实际应用价值。然而，目前尚不清楚在儿童和成年人群中，沿着特定强度带的积累模式是什么样的。因此，我们比较了四个不同人群（儿童、久坐生活方式的成年人、习惯性慢跑者、习惯性马拉松跑者）在特定强度带中的活动积累情况。
分析了 28 名 7 至 11 岁儿童和 61 名 25 至 35 岁成年人的自由生活腰部佩戴加速度计记录。使用 5 秒非重叠的时间区间，通过平均幅度偏差（MAD）评估活动强度，并将其归一化为对应于 3 代谢当量任务的加速度强度（METs）。基于文献，将成年人的数据归一化为 0.091 g MAD，基于实验室实验，将儿童的数据归一化为 0.170 g MAD。将归一化后的时间区间值分为 100 个强度分级。
与成年人相比，儿童在 0.74 至 1.58 个归一化加速度强度范围内积累了更多的活动（均 p<0.005）。与其他组相比，成年慢跑者/跑步者在 7.1 至 11.1 个归一化加速度强度范围内积累了更多的活动（p<0.008）。
儿童自由生活活动的主要部分是相对较低强度的活动，不太可能引起心血管代谢改善。这些探索可以用于为旨在优化健康发育的干预措施的发展提供信息。基于基于探索强度谱确定的干预目标进行随机对照试验的证据越来越多。
