The energy cost of sprint running and the role of metabolic power in setting top performances

Abstract

body mass) was ≈20 % larger, and its angle of application in respect to the horizontal ≈10° smaller, for Bolt, as compared to MLS. Finally, we estimated that, on a 10 % downsloping track Bolt could cover 100 m in 8.2 s. Conclusions The above approach can yield useful information on the bioenergetics and biomechanics of accelerated/decelerated running.Keywords Acceleration · Deceleration · Metabolic power · Mechanical power · Soccer energy expenditure Abbreviations a(t)Acceleration at time t a f Forward acceleration aLaAlactic oxygen debt C 0 Energy cost of running at constant speed on flat terrain (J kg −1 m −1 ) COMCentre of mass C r Energy cost of running (J kg −1 m −1 ) C sr Energy cost of sprint running (J kg −1 m −1 ) Ean Anaerobic energy ED Equivalent distance: distance covered running at constant speed on flat terrain, for a given energy expenditure EDI Equivalent Distance Index: ratio between ED and actual distance covered EM Equivalent body mass ES Equivalent slope = tan (90 − α) F Force F acc Force acting on the subject during accelerated running: M g′ F cost Force acting on the subject during constant speed running: M g gAcceleration of gravity g′ Vectorial sum of af and g: g ′ = a 2 f + g 2 AbstractPurpose To estimate the energetics and biomechanics of accelerated/decelerated running on flat terrain based on its biomechanical similarity to constant speed running up/ down an 'equivalent slope' dictated by the forward acceleration (a f ).Methods Time course of a f allows one to estimate: (1) energy cost of sprint running (C sr ), from the known energy cost of uphill/downhill running, and (2) instantaneous (specific) mechanical accelerating power (P sp = a f × speed).Results In medium-level sprinters (MLS), C sr and metabolic power requirement (P met = C sr × speed) at the onset of a 100-m dash attain ≈50 J kg −1 m −1 , as compared to ≈4 for running at constant speed, and ≈90 W kg −1 . For Bolt's current 100-m world record (9.58 s) the corresponding values attain ≈105 J kg −1 m −1 and ≈200 W kg −1 . This approach, as applied by Osgnach et al. (Med Sci Sports Exerc 42:170-178, 2010) to data obtained by video-analysis during soccer games, has been implemented in portable GPS devices (GPEXE © ), thus yielding P met throughout the match. Actual O 2 consumed, estimated from P met assuming a monoexponential VO 2 response (Patent Pending, TV2014A000074), was close to that determined by portable metabolic carts. Peak P sp (W kg −1 ) was 17.5 and 19.6 for MLS and elite soccer players, and 30 for Bolt. The ratio of horizontal to overall ground reaction force (per kg Communicated by

A simple method for measuring power, force, velocity properties, and mechanical effectiveness in sprint running

“…Because the initial upward movement of the CM is overall smoothed through a relative long time/distance (∼30–40 m; Cavagna et al., ; Slawinski et al., ), we can consider that it does not require any large vertical acceleration, and so that the mean net vertical acceleration of the CM over each step is quasi‐null throughout the sprint acceleration phase. Consequently, applying the fundamental laws of dynamics in the vertical direction, the mean net vertical GRF ( F V ) applied to the body CM over each complete step can be modeled over time as equal to body weight (di Prampero et al., ): where g is the gravitational acceleration (9.81 m/s 2 ).…”

“…Based on the mechanical analyses used in these models, an inverse dynamic approach applied to the runner body center of mass (CM) could give valid estimation of GRF during sprint running acceleration from simple kinematic data, as recently proposed by di Prampero et al. (), but never compared with force plate measurements. This could then be used to obtain the aforementioned sprint mechanical properties without force platform system in typical field conditions of practice.…”

Acceleration-Based Running Intensities of Professional Rugby League Match Play

“…This model considers the energetic cost of accelerated running on flat terrain to be equivalent to the known physiological cost of uphill running at a constant pace 8 . Using the acceleration of a player at any time point, an instantaneous energy cost can be estimated.…”

“…Using the acceleration of a player at any time point, an instantaneous energy cost can be estimated. This cost can be summated to provide an estimation of overall energy expenditure throughout the activity, or multiplied by velocity, as an indication of metabolic power (Pmet; W·kg -1 ) 8 . Recently, this model has been applied to team sports such amongst professional soccer players, Osgnach et al 9 estimated the distance players would have covered at a constant pace, using the total energy expenditure throughout the match (equivalent distance, ED).…”

Movement analysis and metabolic profile of tennis match play: comparison between hard courts and clay courts

“…Hoppe, Baumgart, and Freiwald (2016) examined the metabolic power of both adolescent and adult tennis players. The instantaneous metabolic power (MP) is the quantification of the amount of energy required per unit of time to reconstitute the ATP utilised during performance on the bases of oxidative process; it is expressed in equivalent O 2 units regardless of the actual oxygen consumptions because the latter could be greater, equal of smaller compared to the effective metabolic power (Prampero (di), Botter, & Osgnach, 2015). In the present study, this parameter has been monitored to support the assessment of the player load by analysing the time spent in each intensity threshold.…”