title: Aerobic physical training restores biomechanical properties of Achilles tendon in rats chemically induced to diabetes mellitus.
abstract: The aim of this study is to evaluate if the application of a moderate aerobic exercise protocol reverses the damage caused by diabetes on the mechanical properties of the Achilles tendon.
  
  
  METHODS
  Forty-four rats were divided randomly into four groups as follows: Sedentary Control Group-SCG, Sedentary Diabetic Group-SDG, Trained Control Group-TCG and Trained Diabetic Group-TDG, the trained groups were submitted to a protocol of moderate physical training on a continuous treadmill. For mechanical testing the tendons were fixed in a conventional mechanical testing machine and pulled to the point of failure of the specimen, the cell load of 500N. The parameters were: Elastic Modulus (MPa), Stress Maximum Strength (MPa), Strain Specific Maximum Force (mm), Energy / Tendon Area (N.mm/mm(2)) and Cross-sectional Area (mm(2)).
  
  
  RESULTS
  The evaluation of the biomechanical properties of the Achilles tendon of the SDG indicated that the elastic modulus (MPa) is decreased when compared to the TDG and the other groups (p<0.01). However, the specific deformation (%), the deformation at maximum force (mm), and energy / tendon area (N.mm/mm(2)) of the SDG were significantly higher than in the other groups (p<0.01). Moreover, moderate aerobic training on a treadmill caused the biomechanical property values to move closer to the values shown by the control groups (p>0.01).
  
  
  CONCLUSIONS
  In summary, our study indicates that moderate-intensity aerobic training restored the normal mechanical properties of tendons in diabetic animals, since the elastic modulus (MPa), the specific deformation (%), the deformation of the maximum force (mm) and energy / tendon area (N.mm/mm(2)) approached the values shown by the control groups.
authors.affiliation: Federal University of Pernambuco, Brazil. rodrigo@ufc.br
authors.forename: Rodrigo Ribeiro
authors.initials: RR
authors.lastname: de Oliveira
authors.forename: Márcio Almeida
authors.initials: MA
authors.lastname: Bezerra
authors.forename: Kamilla Dinah Santos
authors.initials: KD
authors.lastname: de Lira
authors.forename: Karyne Albino
authors.initials: KA
authors.lastname: Novaes
authors.forename: Magno Felipe Holanda Barboza Inácio
authors.initials: MF
authors.lastname: Teixeira
authors.forename: Carmen de Castro
authors.initials: Cde C
authors.lastname: Chaves
authors.forename: Silvia Regina Arruda de
authors.initials: SR
authors.lastname: Moraes
mesh_terms: D000125:Achilles Tendon / Q000502:physiology*; D000332:Aerobiosis / Q000502:physiology; D000818:Animals; D001696:Biomechanical Phenomena / Q000502:physiology*; D048909:Diabetes Complications / Q000503:physiopathology / Q000517:prevention & control; D003921:Diabetes Mellitus, Experimental / Q000139:chemically induced / Q000503:physiopathology*; D004326:Drinking / Q000502:physiology; D004435:Eating / Q000502:physiology; D005080:Exercise Test; D008297:Male; D010805:Physical Conditioning, Animal / Q000379:methods*; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D013314:Stress, Mechanical