title: Effects of infrared-LED illumination applied during high-intensity treadmill training in postmenopausal women.
abstract: BACKGROUND
  Technology and physical exercise can enhance physical performance during aging.
  
  
  OBJECTIVE
  The purpose of this study was to investigate the effects of infrared-light-emitting diode (LED) illumination (850 nm) applied during treadmill training.
  
  
  METHODS
  Twenty postmenopausal women participated in this study. They were randomly divided into two groups. The LED group performed treadmill training associated with infrared-LED illumination (n=10) and the control group performed only treadmill training (n=10). The training was performed during 3 months, twice a week during 30 min at intensities between 85 and 90% of maximal heart rate. The irradiation parameters were 31 mW/cm(2), treatment time 30 min, 14,400 J of total energy and 55.8 J/cm(2) of fluence. Physiological, biomechanical, and body composition parameters were measured at the baseline and after 3 months.
  
  
  RESULTS
  Both groups improved the time of tolerance limit (Tlim) (p<0.05) during submaximal constant-speed testing. The peak torque did not differ between groups. However, the results showed significantly higher values of power [from 56±10 to 73±8 W (p=0.002)] and total work [from 1,537±295 to 1,760±262 J (p=0.006)] for the LED group when compared to the control group [power: from 58±14 to 60±15 W (p≥0.05) and total work: from 1,504±404 to 1,622±418 J (p≥0.05)]. The fatigue significantly increased for the control group [from 51±6 to 58±5 % (p=0.04)], but not for the LED group [from 60±10 to 60±4 % (p≥0.05)]. No significant differences in body composition were observed for either group.
  
  
  CONCLUSIONS
  Infrared-LED illumination associated with treadmill training can improve muscle power and delay leg fatigue in postmenopausal women.
authors.affiliation: Optics Group from Instituto de Física de São Carlos, University of São Paulo, São Paulo, Brazil. fer.nanda.rp@hotmail.com
authors.forename: Fernanda Rossi
authors.initials: FR
authors.lastname: Paolillo
authors.forename: Juliana Cristina
authors.initials: JC
authors.lastname: Milan
authors.forename: Isabela Verzola
authors.initials: IV
authors.lastname: Aniceto
authors.forename: Selva Guimarães
authors.initials: SG
authors.lastname: Barreto
authors.forename: José Rubens
authors.initials: JR
authors.lastname: Rebelatto
authors.forename: Audrey
authors.initials: A
authors.lastname: Borghi-Silva
authors.forename: Nivaldo Antonio
authors.initials: NA
authors.lastname: Parizotto
authors.forename: Cristina
authors.initials: C
authors.lastname: Kurachi
authors.forename: Vanderlei Salvador
authors.initials: VS
authors.lastname: Bagnato
mesh_terms: D000368:Aged; D001823:Body Composition; D015444:Exercise; D005080:Exercise Test; D005260:Female; D006801:Humans; D007259:Infrared Rays / Q000627:therapeutic use*; D010789:Phototherapy; D010807:Physical Endurance / Q000528:radiation effects*; D010809:Physical Fitness; D017698:Postmenopause