title: Comparison of cardiopulmonary responses to forward and backward walking and running.
abstract: Backward running has long been used in sports conditioning programs and has recently been incorporated into rehabilitative settings as a method of increasing quadriceps strength while decreasing the joint compressive forces about the knee. Although backward locomotion has been studied kinetically, the metabolic cost of backward walking and/or running has not to our knowledge been previously characterized. Oxygen consumption and other cardiopulmonary variables were measured under constant speed exercise during backward and forward walking at 107.2 m.min-1 and during backward and forward running at 160.8 m.min-1. Peak oxygen consumption (VO2peak) was also measured during maximal incremental backward and forward running. VO2, HR, and blood lactate were significantly higher (P < 0.001) during backward walking and running than during forward walking and running. During backward walking and backward running, subjects exercised at 60% and 84% of their forward VO2peak, respectively. In conclusion, for a given speed, backward locomotion elicits a greater metabolic demand and cardiopulmonary response than forward locomotion. In general, these data suggest that while undergoing rehabilitation, an injured athlete may continue to exercise using backward walking/running at an intensity sufficient enough to maintain cardiovascular fitness levels.
authors.affiliation: Department of Clinical Investigation, William Beaumont Army Medical Center, El Paso, TX 79920-5001.
authors.forename: T W
authors.initials: TW
authors.lastname: Flynn
authors.forename: S M
authors.initials: SM
authors.lastname: Connery
authors.forename: M A
authors.initials: MA
authors.lastname: Smutok
authors.forename: R J
authors.initials: RJ
authors.lastname: Zeballos
authors.forename: I M
authors.initials: IM
authors.lastname: Weisman
mesh_terms: D001265:Athletic Injuries / Q000534:rehabilitation; D005684:Gait / Q000502:physiology; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D007718:Knee Injuries / Q000534:rehabilitation; D007773:Lactates / Q000097:blood; D019344:Lactic Acid; D008297:Male; D010101:Oxygen Consumption / Q000502:physiology; D010146:Pain / Q000534:rehabilitation; D010806:Physical Education and Training / Q000379:methods; D012119:Respiration / Q000502:physiology*; D012420:Running / Q000502:physiology*; D013577:Syndrome; D016138:Walking / Q000502:physiology*
chemical_list: D007773:Lactates; D019344:Lactic Acid