title: Association of habitual long-distance running with the thickness of skeletal muscles and subcutaneous fat in the body extremities and trunk in middle-aged men.
abstract: OBJECTIVE
  We investigated the association of habitual long-distance running with the thickness of skeletal muscles and subcutaneous fat in the body extremities and trunk in middle-aged men using ultrasonography.
  
  
  METHODS
  Three groups of healthy middle-aged men [mean (SD), 62.1 (2.8) years] took part in this investigation: a high-level group of 11 master runners who had competed in a 42.195 km race and run 51.6 (21.7) km every week, an intermediary-level group of 10 master runners who had competed in a 5-20 km race and run 9.3 (4.9) km every week, and a low-level group of 7 untrained men who continued to do no systematic training. The muscle thickness at 8 sites and the subcutaneous fat thickness at 10 sites were measured by B-mode ultrasonography, and were compared among the 3 groups.
  
  
  RESULTS
  The high-level group had 10.0(-1)5.2% higher values for muscle thickness at the erector spinae, hamstrings, tibialis anterior, and triceps surae, compared with the intermediary-level and the low-level groups (p<0.05-0.001). The thickness of the subcutaneous fat about the rectus abdominis and external oblique was lower in the high-level group than in the intermediary-level and the low-level groups (p<0.05).
  
  
  CONCLUSIONS
  Middle-aged male master athletes who habitually run at a high level have more muscle thickness in the lower extremities and trunk, and less subcutaneous fat thickness in the central regions of the body than do middle-aged men who habitually run at an intermediary level or do not run at all.
authors.affiliation: Department of Sports Medicine and Sports Science, Gifu University School of Medicine, Gifu, Japan. oguri@iwata.ssu.ac.jp
authors.forename: K
authors.initials: K
authors.lastname: Oguri
authors.forename: L
authors.initials: L
authors.lastname: Zhao
authors.forename: N
authors.initials: N
authors.lastname: Du
authors.forename: Y
authors.initials: Y
authors.lastname: Kato
authors.forename: K
authors.initials: K
authors.lastname: Miyamoto
authors.forename: M
authors.initials: M
authors.lastname: Hayakawa
authors.forename: J
authors.initials: J
authors.lastname: Kurokawa
authors.forename: S
authors.initials: S
authors.lastname: Nagasaki
authors.forename: T
authors.initials: T
authors.lastname: Matsuoka
mesh_terms: D000009:Abdominal Muscles / Q000000981:diagnostic imaging / Q000502:physiology; D000273:Adipose Tissue / Q000000981:diagnostic imaging / Q000502:physiology*; D000886:Anthropometry; D001823:Body Composition / Q000502:physiology*; D016022:Case-Control Studies; D005121:Extremities / Q000000981:diagnostic imaging / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000000981:diagnostic imaging / Q000502:physiology*; D012420:Running / Q000502:physiology*; D040521:Subcutaneous Tissue / Q000000981:diagnostic imaging / Q000502:physiology*; D014463:Ultrasonography