title: Cut points of muscle strength associated with metabolic syndrome in men.
abstract: BACKGROUND
  The loss of muscle strength with age increases the likelihood of chronic conditions, including metabolic syndrome (MetS). However, the minimal threshold of muscle strength at which the risk for MetS increases has never been established.
  
  
  OBJECTIVE
  This study aimed to identify a threshold of muscle strength associated with MetS in men.
  
  
  METHODS
  We created receiver operating curves for muscle strength and the risk of MetS from a cross-sectional sample of 5685 men age <50 yr and 1541 men age ≥50 yr enrolled in the Aerobics Center Longitudinal Study. The primary outcome measure, the MetS, was defined according to the National Cholesterol Education Program Adult Treatment Panel III criteria. Upper and lower body muscle strength was treated as a composite measure of one-repetition maximum tests on bench and leg press and scaled to body weight. Low muscle strength was defined as the lowest age-specific 20th percentile, whereas high muscle strength was defined as composite muscle strength above the 20th percentile.
  
  
  RESULTS
  In men aged <50 yr, the odds of MetS were 2.20-fold (95% confidence interval = 1.89-2.54) higher in those with low muscle strength, independent of age, smoking, and alcohol intake. The strength of this association was similar for men age ≥50 yr (odds ratio = 2.11, 95% confidence interval = 1.62-2.74). In men age < 50 yr, the composite strength threshold associated with MetS was 2.57 kg·kg body weight, whereas in men age ≥ 50 yr the threshold was 2.35 kg·kg body weight.
  
  
  CONCLUSIONS
  This study is the first to identify a threshold of muscle strength associated with an increased likelihood of MetS in men. Measures of muscle strength may help identify men at risk of chronic disease.
authors.affiliation: 1Manitoba Institute of Child Health, Winnipeg, Manitoba, CANADA; 2Faculty of Medicine, Department of Pediatrics and Child Health, University of Manitoba, Winnipeg, Manitoba, CANADA; 3Pennington Biomedical Research Center, Baton Rouge, LA; 4Department of Kinesiology, Iowa State University, Ames, IA; 5Department of Health, University of Bath, Bath, UNITED KINGDOM; 6Department of Exercise Science, University of South Carolina, Columbia, SC; and 7Department of Epidemiology and Biostatistics, University of South Carolina, Columbia, SC.
authors.forename: Martin
authors.initials: M
authors.lastname: Sénéchal
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: McGavock
authors.forename: Timothy S
authors.initials: TS
authors.lastname: Church
authors.forename: Duck-Chul
authors.initials: DC
authors.lastname: Lee
authors.forename: Conrad P
authors.initials: CP
authors.lastname: Earnest
authors.forename: Xuemei
authors.initials: X
authors.lastname: Sui
authors.forename: Steven N
authors.initials: SN
authors.lastname: Blair
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000886:Anthropometry; D003430:Cross-Sectional Studies; D006801:Humans; D035002:Lower Extremity / Q000502:physiology; D008297:Male; D024821:Metabolic Syndrome / Q000378:metabolism / Q000503:physiopathology*; D008875:Middle Aged; D053580:Muscle Strength / Q000502:physiology*; D010809:Physical Fitness; D012307:Risk Factors; D034941:Upper Extremity / Q000502:physiology; D055815:Young Adult