title: Effects of a physical activity program on the urinary collagen crosslinks in pre- and postmenopausal women.
abstract: BACKGROUND
  This study analyzes the effects of physical exercise on urinary collagen crosslinks, pyridinoline (PYD) and deoxipyridinoline (DPD), in women.
  
  
  METHODS
  Thirty premenopausal (PRE) and 40 postmenopausal (PST) women took part in a six month randomized controlled trial of moderate physical exercise. Moreover, skinfold thickness, muscle strength and flexibility were evaluated.
  
  
  RESULTS
  Basal values of urinary PYD and DPD were higher in postmenopausal women versus premenopausal women (P<0.01). Physical exercise increased in both groups urinary PYD levels (P<0.05) and urinary DPD levels in postmenopausal women (P<0.05). After the exercise program, no changes were observed in the levels of urinary DPD in premenopausal women. Significant improvements in flexibility, muscle strength and decrease in skinfolds thickness were observed in the exercise group. No changes were observed in non-exercise group.
  
  
  CONCLUSIONS
  In conclusion, the physical activity program produced beneficial effects on muscle strength and flexibility and changes in the musculoskeletal system. Also, the physical activity program led to a non-pathological increase in the urinary elimination of bone reabsorption and collagen metabolism biomarkers.
authors.affiliation: Department of Physiology, Sport Sciences Faculty, University of Extremadura, Cáceres, Spain.
authors.forename: Marcos
authors.initials: M
authors.lastname: Maynar
authors.affiliation: Department of Physical Education and Sport, Sport Sciences Faculty, University of Extremadura, Cáceres, Spain.
authors.forename: María C
authors.initials: MC
authors.lastname: Robles
authors.affiliation: Department of Physical Education and Sport, Sport Sciences Faculty, University of Extremadura, Cáceres, Spain - diegomun@unex.es.
authors.forename: Diego
authors.initials: D
authors.lastname: Muñoz
authors.affiliation: Rheumatology Service, Infanta Cristina Hospital, Badajoz, Spain.
authors.forename: José L
authors.initials: JL
authors.lastname: Álvarez
authors.affiliation: Department of Physical Education and Sport, Sport Sciences Faculty, University of Extremadura, Cáceres, Spain.
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Grijota
authors.affiliation: Department of Medical and Surgical Therapeutics, School of Medicine, University of Extremadura, Badajoz, Spain.
authors.forename: María J
authors.initials: MJ
authors.lastname: Caballero
mesh_terms: D000328:Adult; D000596:Amino Acids / Q000652:urine*; D003094:Collagen / Q000378:metabolism*; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D008875:Middle Aged; D053580:Muscle Strength / Q000502:physiology*; D017698:Postmenopause; D017697:Premenopause; D012885:Skinfold Thickness
chemical_list: D000596:Amino Acids; C015484:pyridinoline; D003094:Collagen