Cameron N, Godino J, Nichols J F, Wing D, Hill L, Patrick K
School of Medicine, University of California, San Diego, La Jolla, CA, USA.
Center for Wireless and Population Health Systems, Department of Family Medicine and Public Health, University of California, San Diego, La Jolla, CA, USA.
Int J Obes (Lond). 2017 Jun;41(6):873-877. doi: 10.1038/ijo.2017.49. Epub 2017 Feb 21.
BACKGROUND/OBJECTIVES: Although several studies have reported associations between moderate to vigorous physical activity (MVPA), body fatness and visceral adipose tissue (VAT), the extent to which associations differ among Latinos and non-Latinos remains unclear. This study evaluated the associations between body composition and MVPA in Latino and non-Latino adults.
SUBJECTS/METHODS: An exploratory, cross-sectional analysis was conducted using baseline data collected from 298 overweight adults enrolled in a 12-month randomized controlled trial that tested the efficacy of text messaging to improve weight loss. MVPA, body fatness and VAT were assessed by waist-worn accelerometry, dual-energy x-ray absorptiometry (DXA), and DXA-derived software (GE CoreScan GE, Madison, WI, USA), respectively. Participants with <5 days of accelerometry data or missing DXA data were excluded; 236 participants had complete data. Multivariable linear regression assessed associations between body composition and MVPA per day, defined as time in MVPA, bouts of MVPA (time per bout ⩾10 min), non-bouts of MVPA (time per bout <10 min) and meeting the 150-min MVPA guideline. The modifying influence of ethnicity was modeled with a multiplicative interaction term.
The interaction between ethnicity and MVPA in predicting percent body fat was significant (P=0.01, 95% confidence interval (CI) (0.58, 4.43)) such that a given increase in MVPA was associated with a greater decline in total body fat in non-Latinos compared with Latinos (adjusted for age, sex and accelerometer wear time). There was no interaction between ethnicity and MVPA in predicting VAT (g) (P=0.78, 95% CI (-205.74, 273.17)) and body mass index (BMI) (P=0.18, 95% CI (-0.49, 2.26)).
An increase in MVPA was associated with a larger decrease in body fat, but neither BMI nor VAT, in non-Latinos compared with Latinos. This suggests that changes in VAT and BMI in response to MVPA may be less influenced by ethnicity than is total body fatness.
背景/目的：尽管多项研究报告了中度至剧烈身体活动（MVPA）、体脂和内脏脂肪组织（VAT）之间的关联，但拉丁裔和非拉丁裔之间这种关联的差异程度仍不清楚。本研究评估了拉丁裔和非拉丁裔成年人身体成分与MVPA之间的关联。
受试者/方法：采用横断面分析，使用从298名超重成年人收集的基线数据，这些成年人参加了一项为期12个月的随机对照试验，该试验测试了短信促进减肥的效果。MVPA、体脂和VAT分别通过腰部佩戴的加速度计、双能X线吸收法（DXA）以及DXA衍生软件（美国威斯康星州麦迪逊市通用电气公司的GE CoreScan GE）进行评估。加速度计数据记录天数少于5天或DXA数据缺失的参与者被排除；236名参与者有完整数据。多变量线性回归评估了身体成分与每天MVPA之间的关联，MVPA定义为MVPA时间、MVPA发作次数（每次发作时间⩾10分钟）、非MVPA发作次数（每次发作时间<10分钟）以及达到150分钟MVPA指南的情况。种族的修正影响通过乘法交互项进行建模。
在预测体脂百分比方面，种族与MVPA之间的交互作用显著（P = 0.01，95%置信区间（CI）（0.58，4.43）），因此与拉丁裔相比，非拉丁裔中给定的MVPA增加与全身脂肪的更大下降相关（根据年龄、性别和加速度计佩戴时间进行调整）。在预测VAT（克）（P = 0.78，95% CI（-205.74，273.17））和体重指数（BMI）（P = 0.18，95% CI（-0.49，2.26））方面，种族与MVPA之间没有交互作用。
与拉丁裔相比，非拉丁裔中MVPA增加与身体脂肪的更大减少相关，但与BMI和VAT无关。这表明，与全身脂肪相比，种族对VAT和BMI因MVPA而发生变化的影响可能较小。
