External work in walking

Cavagna, G; Saibene, F.; Margaria, R

doi:10.1152/jappl.1963.18.1.1

Cited by 303 publications

(183 citation statements)

References 0 publications

Supporting

Mentioning

177

Contrasting

Unclassified

Order By: Relevance

“…The characters in Bold indicate that the displacement in forward direction and the force in vertical direction are responsible for most of W ext . In the lateral direction both displacement and force are small (about 1% of vertical and forward work in walking [31]) and are neglected in this study. Figure 6.…”

Section: External Workmentioning

confidence: 99%

Symmetry and Asymmetry in Bouncing Gaits

Cavagna

2010

Symmetry

View full text Add to dashboard Cite

Abstract:In running, hopping and trotting gaits, the center of mass of the body oscillates each step below and above an equilibrium position where the vertical force on the ground equals body weight. In trotting and low speed human running, the average vertical acceleration of the center of mass during the lower part of the oscillation equals that of the upper part, the duration of the lower part equals that of the upper part and the step frequency equals the resonant frequency of the bouncing system: we define this as on-offground symmetric rebound. In hopping and high speed human running, the average vertical acceleration of the center of mass during the lower part of the oscillation exceeds that of the upper part, the duration of the upper part exceeds that of the lower part and the step frequency is lower than the resonant frequency of the bouncing system: we define this as on-off-ground asymmetric rebound. Here we examine the physical and physiological constraints resulting in this on-off-ground symmetry and asymmetry of the rebound. Furthermore, the average force exerted during the brake when the body decelerates downwards and forwards is greater than that exerted during the push when the body is reaccelerated upwards and forwards. This landing-takeoff asymmetry, which would be nil in the elastic rebound of the symmetric spring-mass model for running and hopping, suggests a less efficient elastic energy storage and recovery during the bouncing step. During hopping, running and trotting the landing-takeoff asymmetry and the mass-specific vertical stiffness are smaller in larger animals than in the smaller animals suggesting a more efficient rebound in larger animals.

show abstract

Section: External Workmentioning

confidence: 99%

Symmetry and Asymmetry in Bouncing Gaits

Cavagna

2010

Symmetry

View full text Add to dashboard Cite

show abstract

“…Human behavior entails the use ofmultiple joints and connecting muscles, providing additional sources of error. Biomechanical analyses of gait (Cavagna & Margaria, 1966;Cavagna, Saibene, & Margaria, 1963;Liberson, 1965;Morris, 1973;Saunders, Inman, & Eberhart, 1953) reveal that normal walking causes the waist to rise and fall as well as move left and right in a spiral pattern. These movements, and the impact ofthe foot meeting the floor, give rise to complex patterns of acceleration that cannot be reproduced with the same degree of precision as a decaying pendulum and the spinning calibration device.…”

Section: Between-unit Variabilitymentioning

confidence: 99%

Fully proportional actigraphy: A new instrument

Tryon

Williams²

1996

Behavior Research Methods, Instruments, & Computers

165

145

View full text Add to dashboard Cite

The relevance of activity measurement is reviewed. Technical information regarding a new, small, lightweight, fully proportional accelerometer-based activity monitor suited for a wide range of wrist, waist, and ankle activity measurements over extended time periods in free-ranging persons is presented. Calibration data demonstrating within-and between-device reliability and validity are presented. Field trial data are presented showing that wrist and waist actigraphs can predict kilocalories of energy expended. The issue of how activity monitors should be validated is discussed. Instrument reliability is distinguished from clinical repeatability. Recommendations are provided to assist investigators with instrument selection.There are many reasons why a high-quality ambulatory activity monitor is desirable. Activity is a major dimension of infant temperament

show abstract

“…The speed range reflected normal walking rates (1.7-3.3 mph; cf. Cavagna, Saibene, & Margaria, 1963). Treadmill speed and grade were controlled by the computer that generated the VE.…”

Section: Materials and Apparatusmentioning

confidence: 99%

Multimodally specified energy expenditure and action-based distance judgments

2013

View full text Add to dashboard Cite

Previous research has demonstrated that perceived self-motion can be manipulated by the relation between optic flow rate and walking rate. Other studies have revealed that verbal reports of perceived distance are influenced by the energy that would be expended to traverse the distance in question. In an effort to integrate these findings, we investigated how action-based distance judgments are influenced by multimodally specified energy expenditure (MSEE)-the metabolic cost associated with traversing an optically specified distance-using a virtual-reality treadmill environment. The energy expenditure associated with walking, measured as the volume of oxygen consumed, was manipulated by changing treadmill speed or grade. Optically specified distance was manipulated by changing the virtual optic flow rate. All three manipulations of MSEE (walking rate, grade, and optic flow rate) influenced distance reports in the predicted directions and to equivalent degrees. decoupled optical information about forward self-motion from actual walking rate (and thus from proprioceptive information about forward motion) by having participants walk on a treadmill towed by a tractor. When the treadmill speed was slower than the tractor speed (optic flow suggested faster walking), participants underestimated a target distance when later asked to blind-walk it. Likewise, participants overestimated when the treadmill speed was faster than the tractor speed. This result was explained in terms of visuomotor calibration between optical and proprioceptive information about self-motion. KeywordsOther nonoptical influences on distance reports resist visuomotor calibration explanations. Energy expenditure influences prospective (verbal) distance reports even when environmental (i.e., optical) cues remain constant (Proffitt et al.,

show abstract

External work in walking

Cited by 303 publications

References 0 publications

Symmetry and Asymmetry in Bouncing Gaits

Symmetry and Asymmetry in Bouncing Gaits

Fully proportional actigraphy: A new instrument

Multimodally specified energy expenditure and action-based distance judgments

Contact Info

Product

Resources

About