title: The effects of treadmill type on heart rate and pain threshold velocity in individuals with lower-extremity musculoskeletal pain.
abstract: METHODS
  This study utilized a quasi-experimental design in which subjects served as their own controls.
  
  
  OBJECTIVE
  To determine whether heart rate, pain threshold velocity, and pain perception varied in patients running on a soft-belt treadmill versus a standard hard-belt treadmill.
  
  
  BACKGROUND
  According to promotional literature, the relatively new Orbiter soft-belt tread produces a greater increase in heart rate at a given velocity as well as a higher velocity tolerance while walking or running. The manufacturer also asserts that decreased forces transmitted through the lower extremity should decrease pain levels while exercising on the soft-belt treadmill.
  
  
  METHODS
  Twenty-seven subjects walked or ran on each of 2 treadmills at incrementally increasing velocities until they experienced either the onset of pain or an increase in pain from baseline levels. Locomotion continued for 2 minutes after that, during which time heart rate and pain level on a visual analog scale (VAS) were recorded.
  
  
  RESULTS
  Two univariate paired t tests and a Wilcoxon's signed rank test revealed a greater heart rate and pain threshold velocity when using the soft-belt treadmill with no statistical difference in the pain reported between the 2 treadmills.
  
  
  CONCLUSIONS
  Our study revealed a 10% higher heart rate and a 14.5% higher pain threshold velocity with the soft-belt treadmill compared to a hard-belt treadmill. These differences are considered clinically meaningful.
authors.affiliation: Eglin AFB Hospital, Eglin, FL, USA.
authors.forename: Brian J
authors.initials: BJ
authors.lastname: Langford
authors.forename: Evan M
authors.initials: EM
authors.lastname: Jones
authors.forename: James E
authors.initials: JE
authors.lastname: Cowan
authors.forename: Danny J
authors.initials: DJ
authors.lastname: Hollingsworth
authors.forename: Gail D
authors.initials: GD
authors.lastname: Deyle
authors.forename: S Christie
authors.initials: SC
authors.lastname: Douglas
authors.forename: Stephen C
authors.initials: SC
authors.lastname: Allison
mesh_terms: D000293:Adolescent; D000328:Adult; D004867:Equipment Design; D005080:Exercise Test / Q000295:instrumentation*; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D017288:Pain Threshold; D015203:Reproducibility of Results; D012420:Running