title: Predictors of cardiorespiratory fitness in female and male adults with different body mass index: National Health and Nutrition Examination Survey 1999-2004 dataset.
abstract: The aim of this study was to explore factors affecting cardiorespiratory fitness in males and females with different body mass index (BMI).
  
  
  
  The National Health and Nutrition Examination Survey 1999-2004 data were used for this retrospective study. Estimated maximal oxygen uptake (VO2max) is surrogate for cardiorespiratory fitness (CRF). Univariate and multivariate linear regression analyses were performed to explore whether study variables were associated with estimated VO2maxstratified by gender and BMI categories.
  
  
  
  A total of 3292 subjects 20-49 years of age were included in the analysis. CRF significantly decreased as BMI increased in both females and males. Ethnic difference was found in normal BMI in both genders and obese females; homocysteine was significantly negatively associated with estimated VO2max, as was total cholesterol. Obese male subjects with diabetes had a lower estimated VO2maxthan those without diabetes, and C-reactive protein (CRP) level and vitamin B12 level were significantly negatively associated with CRF. Female subjects with diabetes had higher estimated VO2maxthan those without diabetes. Folate was significantly positively correlated with estimated VO2max, whereas CRP was negatively correlated in obese female.
  
  
  
  There are different predictors of CRF in males and females, and in individuals with different BMI. Key messages Different BMI classes are associated with different predictors of cardiorespiratory fitness. Indicators of cardiorespiratory fitness differ between sexes.
authors.affiliation: a The First Division in the Department of Endocrinology , Guangdong General Hospital, Guangdong Academy of Medical Sciences , Guangzhou , China.
authors.forename: Liang
authors.initials: L
authors.lastname: Chen
authors.affiliation: a The First Division in the Department of Endocrinology , Guangdong General Hospital, Guangdong Academy of Medical Sciences , Guangzhou , China.
authors.forename: Jian
authors.initials: J
authors.lastname: Kuang
authors.affiliation: a The First Division in the Department of Endocrinology , Guangdong General Hospital, Guangdong Academy of Medical Sciences , Guangzhou , China.
authors.forename: Jian-Hao
authors.initials: JH
authors.lastname: Pei
authors.affiliation: a The First Division in the Department of Endocrinology , Guangdong General Hospital, Guangdong Academy of Medical Sciences , Guangzhou , China.
authors.forename: Hong-Mei
authors.initials: HM
authors.lastname: Chen
authors.affiliation: a The First Division in the Department of Endocrinology , Guangdong General Hospital, Guangdong Academy of Medical Sciences , Guangzhou , China.
authors.forename: Zhong
authors.initials: Z
authors.lastname: Chen
authors.affiliation: a The First Division in the Department of Endocrinology , Guangdong General Hospital, Guangdong Academy of Medical Sciences , Guangzhou , China.
authors.forename: Zhong-Wen
authors.initials: ZW
authors.lastname: Li
authors.affiliation: a The First Division in the Department of Endocrinology , Guangdong General Hospital, Guangdong Academy of Medical Sciences , Guangzhou , China.
authors.forename: Hua-Zhang
authors.initials: HZ
authors.lastname: Yang
authors.affiliation: a The First Division in the Department of Endocrinology , Guangdong General Hospital, Guangdong Academy of Medical Sciences , Guangzhou , China.
authors.forename: Xiao-Ying
authors.initials: XY
authors.lastname: Fu
authors.affiliation: a The First Division in the Department of Endocrinology , Guangdong General Hospital, Guangdong Academy of Medical Sciences , Guangzhou , China.
authors.forename: Long
authors.initials: L
authors.lastname: Wang
authors.affiliation: a The First Division in the Department of Endocrinology , Guangdong General Hospital, Guangdong Academy of Medical Sciences , Guangzhou , China.
authors.forename: Zhi-Jiang
authors.initials: ZJ
authors.lastname: Chen
authors.affiliation: a The First Division in the Department of Endocrinology , Guangdong General Hospital, Guangdong Academy of Medical Sciences , Guangzhou , China.
authors.forename: Shui-Qing
authors.initials: SQ
authors.lastname: Lai
authors.affiliation: a The First Division in the Department of Endocrinology , Guangdong General Hospital, Guangdong Academy of Medical Sciences , Guangzhou , China.
authors.forename: Shu-Ting
authors.initials: ST
authors.lastname: Zhang
mesh_terms: D000328:Adult; D015992:Body Mass Index; D002097:C-Reactive Protein / Q000378:metabolism; D000072599:Cardiorespiratory Fitness / Q000502:physiology*; D005260:Female; D005492:Folic Acid; D006801:Humans; D008297:Male; D008875:Middle Aged; D009749:Nutrition Surveys / Q000379:methods*; D009765:Obesity / Q000378:metabolism; D010100:Oxygen / Q000378:metabolism*; D010809:Physical Fitness / Q000502:physiology*; D012189:Retrospective Studies; D014805:Vitamin B 12
chemical_list: D002097:C-Reactive Protein; D005492:Folic Acid; D014805:Vitamin B 12; D010100:Oxygen
keywords: Body mass index; National Health and Nutrition Examination Survey; cardiorespiratory fitness