Kim Tae Nyun, Park Man Sik, Kim You Jeong, Lee Eun Ju, Kim Mi-Kyung, Kim Jung Min, Ko Kyung Soo, Rhee Byoung Doo, Won Jong Chul
Department of Internal Medicine, Inje University College of Medicine, Busan, Korea; Division of Endocrinology and Metabolism, Cardiovascular and Metabolic Disease Center, Inje University, Busan, Korea.
Department of Statistics, College of Natural Sciences, Sungshin Women's University, Seoul, Korea.
PLoS One. 2014 Jun 17;9(6):e100118. doi: 10.1371/journal.pone.0100118. eCollection 2014.
Previous studies have shown that low cardiorespiratory fitness (CRF), visceral obesity and low muscle mass may share pathophysiological mechanisms, such as insulin resistance and chronic inflammation. In this study, we investigated whether low CRF is associated with low muscle mass, visceral obesity, and visceral obesity combined with low muscle mass.
The associations between CRF and low muscle mass and combined low muscle mass and visceral obesity were examined in 298 apparently healthy adults aged 20-70 years. Low muscle mass was defined using a skeletal muscle mass index (SMI) that was calculated using dual energy X-ray absorptiometry. Visceral obesity was defined as a visceral fat area (VFA) exceeding 100 cm2 in women and 130 cm2 in men. We classified the participants into 4 low muscle mass/visceral obesity groups according to SMI and VFA. CRF was measured using a cycle ergometer test.
CRF level correlated positively with SMI and negatively with VFA. Individuals with low muscle mass had lower CRF values than those without low muscle mass. After adjustment for age, sex, lifestyle factors, and markers for insulin resistance and inflammation, participants in the lowest quartile of CRF had an odds ratio (OR) for low muscle mass of 4.98 compared with those in the highest quartile (95% confidence interval (CI) = 1.19-12.99; P for trend = 0.001) and an OR for combined low muscle mass and visceral obesity of 31.46 (95% CI = 4.31-229.68; P for trend = 0.001).
Individuals with lower CRF exhibited increased risk of low muscle mass and combined low muscle mass and visceral obesity. These results suggest that low CRF may be a potential indicator for low muscle mass and combined low muscle mass and visceral obesity in Korean adults.
既往研究表明，低心肺适能（CRF）、内脏肥胖和低肌肉量可能具有共同的病理生理机制，如胰岛素抵抗和慢性炎症。在本研究中，我们调查了低CRF是否与低肌肉量、内脏肥胖以及内脏肥胖合并低肌肉量相关。
在298名年龄在20至70岁的表面健康成年人中，研究了CRF与低肌肉量以及低肌肉量合并内脏肥胖之间的关联。低肌肉量通过使用双能X线吸收法计算的骨骼肌质量指数（SMI）来定义。内脏肥胖定义为女性内脏脂肪面积（VFA）超过100 cm²，男性超过130 cm²。我们根据SMI和VFA将参与者分为4个低肌肉量/内脏肥胖组。使用自行车测力计测试来测量CRF。
CRF水平与SMI呈正相关，与VFA呈负相关。低肌肉量个体的CRF值低于非低肌肉量个体。在调整年龄、性别、生活方式因素以及胰岛素抵抗和炎症标志物后，CRF最低四分位数的参与者与最高四分位数的参与者相比，低肌肉量的比值比（OR）为4.98（95%置信区间（CI）=1.19 - 12.99；趋势P值=0.001），低肌肉量合并内脏肥胖的OR为31.46（95% CI = 4.31 - 229.68；趋势P值=0.001）。
CRF较低的个体出现低肌肉量以及低肌肉量合并内脏肥胖的风险增加。这些结果表明，低CRF可能是韩国成年人低肌肉量以及低肌肉量合并内脏肥胖的一个潜在指标。
