The resonant step frequency in human running

Cavagna, G; Mantovani, M.; Willems, Patrick; Musch, G

doi:10.1007/s004240050451

Cited by 87 publications

(77 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Despite this complexity, simple patterns often emerge that are consistent with low-dimensional mechanical models or templates (Full and Koditschek, 1999). Legged locomotion in the sagittal plane is consistent with a spring loaded inverted pendulum (SLIP) (Cavagna et al, 1997;McMahon and Cheng, 1990;Blickhan, 1989;Schwind and Koditschek, 2000), a result that scales across the number of legs and three orders of magnitude of body mass (Blickhan and Full, 1993;Farley et al, 1993). Similarly, horizontal plane locomotion in sprawled-posture animals is well characterized by the lateral leg spring template (LLS) (Schmitt and Holmes, 2000a;Schmitt and Holmes, 2000b), because animals also bounce side-to-side.…”

Section: Neuromechanical Modelsmentioning

confidence: 90%

Task-level control of rapid wall following in the American cockroach

Cowan

Lee

2006

Journal of Experimental Biology

102

146

View full text Add to dashboard Cite

SUMMARY The American cockroach, Periplaneta americana, is reported to follow walls at a rate of up to 25 turns s–1. During high-speed wall following, a cockroach holds its antenna relatively still at the base while the flagellum bends in response to upcoming protrusions. We present a simple mechanosensory model for the task-level dynamics of wall following. In the model a torsional, mass-damper system describes the cockroach's turning dynamics, and a simplified antenna measures distance from the cockroach's centerline to a wall. The model predicts that stabilizing neural feedback requires both proportional feedback (difference between the actual and desired distance to wall) and derivative feedback (velocity of wall convergence) information from the antenna. To test this prediction, we fit a closed-loop proportional-derivative control model to trials in which blinded cockroaches encountered an angled wall (30° or 45°) while running. We used the average state of the cockroach in each of its first four strides after first contacting the angled wall to predict the state in each subsequent stride. Nonlinear statistical regression provided best-fit model parameters. We rejected the hypothesis that proportional feedback alone was sufficient. A derivative (velocity) feedback term in the control model was necessary for stability.

show abstract

Section: Neuromechanical Modelsmentioning

confidence: 90%

Task-level control of rapid wall following in the American cockroach

Cowan

Lee

2006

Journal of Experimental Biology

102

146

View full text Add to dashboard Cite

show abstract

“…On the other hand recent findings show that the metabolic energy expenditure decreases when hopping frequency is increased above the preferred frequency and the contact time is decreased [78,79]. Furthermore, a contribution of the contractile machinery to the mechanical work done is evidenced at low running speeds in humans by a greater energy expenditure when the mechanical work and the contact time are made greater by decreasing the step frequency below the freely chosen step frequency [41] (Figure 15). These findings indicate that positive work production by muscles is increased when the duration of the stretch-shorten cycle is increased.…”

Section: Effect Of Running Speed On Landing-takeoff Asymmetry In Adulmentioning

confidence: 91%

“…As shown in [40] and [41], the mass-specific internal work done per unit distance to accelerate the limbs relative to the center of mass of the body, W int /M b L, can now be conveniently calculated from the experimental values of step length L (m), average running speed V f (m s -1 ), step frequency f (Hz) and mass of the body M b (kg) according to the equation:…”

Section: Internal Workmentioning

confidence: 99%

“…Tuning the step frequency to the resonant frequency of the bouncing system during running at low speeds may result in a minimum of metabolic energy expenditure and in a maximum of the efficiency of conversion of stored chemical energy into positive mechanical work. This possibility was investigated by measuring the metabolic energy expenditure, from the oxygen consumption in unit time, the total mechanical power (section 2.4), and the mechanical efficiency during running at three given speeds (5.3, 8.0 and 11.1 km h -1 ) with different step frequencies [41].…”

Section: Tuning Step Frequency To the Resonant Frequency Of The Bouncmentioning

confidence: 99%

“…However the best match between f and f s takes place only in proximity of the freely chosen step frequency (2.6-2.8 Hz). It is concluded that during running at speeds less than 13 km h -1 energy is saved by tuning step frequency to the resonant frequency of the bouncing system, even if this requires a mechanical power larger than necessary [41]. …”

Section: Tuning Step Frequency To the Resonant Frequency Of The Bouncmentioning

confidence: 99%

See 2 more Smart Citations

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

Biomechanical Constraints and Economy of Movement in Endurance Performance

Williams¹

2000

Endurance in Sport

View full text Add to dashboard Cite

The resonant step frequency in human running

Cited by 87 publications

References 19 publications

Task-level control of rapid wall following in the American cockroach

Task-level control of rapid wall following in the American cockroach

Symmetry and Asymmetry in Bouncing Gaits

Biomechanical Constraints and Economy of Movement in Endurance Performance

Contact Info

Product

Resources

About