Effects of infrared-LED illumination applied during high-intensity treadmill training in postmenopausal women

Photomed Laser Surg. 2011 Sep;29(9):639-45. doi: 10.1089/pho.2010.2961. Epub 2011 Jul 12.


Background data: 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.

Materials and 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.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Aged
  • Body Composition
  • Exercise Test
  • Exercise*
  • Female
  • Humans
  • Infrared Rays / therapeutic use*
  • Phototherapy*
  • Physical Endurance / radiation effects*
  • Physical Fitness*
  • Postmenopause*