¿por qué valorar el salto vertical?

¿de que depende el rendimiento en el salto vertical?

¿qué cualidad mecánica del sistema neuromuscular me interesa mejorar más?

Cross et al Optimal loading in sled sprinting

IJSPP In press 2017

2

Figure I –– (A) Graphical representation of the force-velocity and

power-velocity relationship profiled via a multiple-trial method using

resisted sleds. Each data point represents values derived from a single

individual trial at different loading protocols. ! " and #" represent the

y- and x-intercepts of the linear regression, and the theoretical maxi-

mum of force and velocity able to be produced in absence of their

opposing unit. $' ( ) represents the maximum power produced, deter-

mined as the peak of the polynomial fit between power and velocity.

Furthermore, the graphical calculation of optimal force (! +, -) and ve-

locity (#+, -) variables are shown. (B) Mean of individual force-ve-

locity-power profiles of recreational athletes (grey lines), compared

to sprinters (black lines).

optimal loading characteristics across multiple treadmill

sprints,14-16

although none calculated the exact conditions for

$' ( ) with respect to plotting FvP relationships. In any case,

dissimilarities between treadmill and over-ground sprinting17

and limited access to such technology for training purposes

render the results of this research of little use to the general

practitioner.

Power profiling during over-ground sprinting has been proven

possible,4,18

with authors highlighting the central role of hori-

zontal power in performance. However, despite the prevalence

of resisted sprinting protocols in the literature (e.g. sprinting

sleds10

), no attempt has been made to profile optimal loading

conditions for maximising power production. Therefore, the

aims of this study were to: (1) assess whether a multiple-trial

method, using resisted sprint sleds to supply resistance, could

be used to accurately and reliably profile FvP relationships

during over-ground sprinting; (2) quantify and present optimal

loading conditions for maximising power and; (3) compare

mechanical characteristics between highly trained sprinters

and recreational cohorts.

Methods

Participants

12 recreational level mixed-sport athletes and 15 highly-

trained sprinters gave their written informed consent to take

part in this study, after being made aware of the procedures,

and risks and benefits of study participation. The two cohorts

were selected to provide a proof-of-concept for the applicabil-

ity of the profiling method to athletes both highly familiar with

resisted sprinting, and athletes with mixed familiarity levels.

Sprinters were required to have attained a performance stand-

ard of at least 750 IAAF points19

in an event ≤400 m within

the previous season. The mean current (within season) perfor-

mance level of the group was 883±126 (mean±SD) IAAF

points19

in their primary event, including three national cham-

pions and record holders. ≥2 years of sprint training experience

were required, including ≥1 years using resisted sprint meth-

ods. Athletes were devoid of lower extremity injuries (>3

months pre-testing). Athletes were either determined as famil-

iar with the testing modality (i.e. having performed resisted

sprinting with loads ≥50% of body-mass [BM]), or were pro-

vided with a familiarisation session >72 hours pre-testing

(N=3). The study was approved by the Auckland University of

Technology Ethics Committee (#15/61).

Design

This study sought to investigate whether multiple trials of sled-

resisted sprints could be used to determine mechanical rela-

tionships, and optimal loading for maximising horizontal

power, in recreational and sprint cohorts. A repeated measures

protocol was implemented to measure the changes in perfor-

mance, determined from a combination of aerodynamic drag,

friction force and maximum velocity, across sprint trials while

resisted by a range of sled loads. Recruitment and subsequent

testing occurred throughout the competitive track and field

season of 2015. Inter-session test-retest reliability of all varia-

bles was assessed in 9 recreational athletes, who performed

two testing procedures separated by a 7 day period. Reassess-

ment took place using identical testing parameters to the first

session, at the same time of day to minimise diurnal fluctua-

tions, with athletes asked to standardise their surrounding ac-

tivities. All testing occurred following ~24 hours rest.

Methodology

All testing procedures were completed in the same running-

lane of an indoor Mondo track. Athletes were instructed to

wear their typical footwear for maximal sprinting. Recrea-

tional athletes wore standard athletic footwear and sprinters

wore sprinting spikes. A standardised ~30 min warm-up in-

cluding jogging, dynamic stretching, and submaximal 45 m

stride outs (70, 80 and 90% of maximal self-selected effort)

was performed. A 5 min active-recovery period directly pre-

ceded the commencement of testing, during which procedures

PERFIL DEL

DEPORTISTA

PERFILFUERZA-VELOCIDAD Y POTENIA-VELOCIDAD PARA DOS SUJETOS

SALTO VERTICAL CON CONTRAMOVIMIENTO (CMJ)

Diferentes pesos para el cácululo de la curva fuerza (peso) velocidad (altura)

Valida para analizar las carácterísticas de velocidad en el salto del sujeto

Valorar la progresión en el transcurso del entrenamiento

Tambíen se puede conseguir la curva de potencia aplicando la siguiente

formula: P=(Pc + Pb) * 9,81* 2 ∙ 9,8 ∙ ℎ

COEFICIENTE FUERZA VELOCIDAD= CMJP/CMJ

Según el valor de esta relación se determinan las características delsujeto en relación con las variables fuerza-velocidad y el efectoproducido sobre ellas por el entrenamiento; si el cociente es muy alto ocrece con el entrenamiento es que le estamos dando un énfasis altrabajo de fuerza máxima, por el contrario si baja estaremos primandoel trabajo de velocidad con cargas ligeras

Este cociente podría ser utilizado con todos los pesos utilizados en eltest

El peso utilizado no tiene que ser necesariamente igual al peso corporal(solo sería aconsejable en sujetos con gran fuerza y potencia)

El peso máximo que se debería utilizar no debería ser superior a aquelcon el que la altura del salto no fuese inferior a 13-14 cm.

CMJ peso x CMJ Resultado Cociente

+

-

= +

= -

+/?

-

Interpretación en los posibles cambios en el cociente CMJ peso%/CMJ

ARRANCA

DA

Velocidad media acelerativa (m/s) % de 1 RM

Velocidad mediaacelerativa con 1

Rm

1,15 (±0,12) 91 (±5,6) 1,04 (±0,09)

Velocidad media acelerativa (m/s) % de 1 RM

Velocidad mediaacelerativa con 1

Rm

1,15 (±0,12) 91 (±5,6) 1,04 (±0,09)

1,09 (±0,1) 87 (±6,7) 0,9 (± 0,08)Velocidad media acelerativa (m/s) % de 1 RM

Velocidad mediaacelerativa con 1

Rm

1,09 (±0,1) 87 (±6,7) 0,9 (± 0,08)

CARGADA

Velocidad media acelerativa (m/s) % de 1 RM

Velocidad mediaacelerativa con 1

Rm

0,76 (±0,09) 65 (±7,6) 0,31 (±0,07)

SENTADIL

LA

Velocidad media acelerativa (m/s) % de 1 RM

Velocidad mediaacelerativa con 1

Rm

1,15 (±0,1) 40 (±5,5) 0,2 (±0,05)

PRESS

BANCA

SQUAT

JUMP

“the load that maximizes power output

was 0%1-RM “JIMENEZ REYES, P. ET

AL (2015)

CONTRAMOVEMENT JUMP

“jump height close to 20 cm”

Loturco, I. et al (2015)

Jimenez Reyes, P. Et al (2016)

CARRERA

LASTRADA"69-96% of body-mass,

dependent on friction conditions”

(Matt R. Cross et al 2016)

N=51 hombres atletas (sprinter y lanzadores)

Objetivo: Examinar la relación entre la carga relativa en las sentadillascompletas y la altura alcanzada en los ejercicios de salto-sentadilla (JS) ydeterminar la carga que maximiza la potencia de salida de los atletas de altonivel.

Métodos: Se midieron la repetición máxima en full squat (1-RM) y laaltura de JS (JH) con cargas de 17 a 97 kg en 2 sesiones separadas por 48 h

Resultados: Los análisis de regresión lineal mostraron que JH (R2 = 0,992± 0,005) y la disminución de salto (JD) que cada carga producida conrespecto al salto de contramovimiento sin peso (CMJ) (R2 = 0,992 ± 0,007)están altamente correlacionadas con el % de squat en 1-RM, lo quesignifica que las intensidades de entrenamiento pueden prescribirse usandolos valores JH y JD

Training & Test ing 349

Gonz á lez-Badillo JJ, S á nchez-Medina L. Movement Velocit y as a Measure of Loading Intensit y … Int J Sports Med 2010; 31: 347 – 352

imal st rength. From T1 to T2, the mean 1RM value improved by

9.3 ± 6.7 % (changing from 86.9 ± 15.2 kg to 94.5 ± 15.2 kg). Despite

this fact , the diff erence in mean test velocity was only

of − 0.01 ± 0.05 m · s − 1 or, w hen expressed as absolute values, of

0.02 ± 0.02 m · s − 1 , changing from 0.78 ± 0.05 m · s − 1 to 0.76 ±

0.05 m · s − 1 . − − Table 1 shows the diff erences in MPV at tained

w ith each percentage of 1RM for the 56 subjects w ho performed

tw ice the BP test . Despite the observed change in 1RM values

from T1 to T2, after 6-wk of t raining, mean ICC for MPV at tained

w ith each load ( % 1RM) was 0.87 (range: 0.81 – 0.91; CV: 0.0 –

3.6 % ; 95 % confi dence interval: 0.68 – 0.95). When plot t ing per-

centage of change in the 1RM values against the diff erences

between mean test velocit y from T1 to T2, a negat ive and sig-

nifi cant correlat ion could be ident ifi ed (r = − 0.42, P < 0.01). A

posit ive, but non-signifi cant , correlat ion (r = 0.23, P = 0.091) was

found when comparing changes in V 1RM from T1 to T2 and diff er-

ences in mean test velocity.

− − Fig. 3 provides examples of the load-velocit y relat ionships for

three representat ive subjects. − − Fig. 3a corresponds to one

subject w ho improved his 1RM value by 11.8 % (from 85 – 95 kg).

V 1RM in T1 (0.16 m · s − 1 ) was almost ident ical to that of T2

(0.14 m · s − 1 ), while MPV w ith each % 1RM and mean test velocity

remained stable. − − Fig. 3b shows an ext reme case, the subject

w ho showed the greatest change in the load-velocity curve from

T1 to T2. He improved his 1RM (14.8 % , from 115 – 132 kg), but

V 1RM in T2 (0.06 m · s − 1 ) and mean test velocity (0.69 m · s − 1 ) were

both considerably lower to those of T1 (0.17 m · s − 1 and

0.75 m · s − 1 , respect ively). MPV at tained w ith each relat ive load

were lower in T2 than in T1. Finally, the subject whose curves

are show n in − − Fig. 3c did not improve his maximal st rength

(1RM value slight ly decreased by 2.2 % , from 112.5 – 110 kg). For

this subject , V 1RM in T1 (0.10 m · s − 1 ) and T2 (0.12 m · s − 1 ) were

very similar, and mean test velocity was the same on both occa-

sions (0.73 m · s − 1 ). MPV at tained w ith each percentage of 1RM

in T1 and T2 were almost ident ical.

Stability in the load-velocity relationship regardless of

individual relative strength

In order to study whether the velocit y at tained w ith each % 1RM

was dependent upon individual st rength levels, subjects were

ranked according to relat ive st rength rat io (RSR) and the total

sample of 176 tests was fur ther divided into four subgroups:

group 1 (G1), n = 45, RSR − 0.97; group 2 (G2), n = 44, 0.97 <

RSR − 1.09; group 3 (G3), n = 44, 1.09 < RSR − 1.22; and group 4

(G4), n = 43, RSR > 1.22. Mean test velocity for G4 was signifi -

cant ly lower (P < 0.05) than for all other groups. No signifi cant

diff erences in V 1RM were found between groups, although cer-

tain tendency towards slight ly lower values was detected for the

st rongest group (G4) ( − − Table 2 ).

Predicting load ( % 1RM) from velocity data

A predict ion equat ion to est imate relat ive load (Load, % 1RM)

from mean propulsive velocity data (MPV, in m · s − 1 ) could be

obtained: Load = 8.4326 MPV 2 – 73.501 MPV + 112.33 (R 2 = 0.981;

SEE = 3.56 % 1RM). In the case that mean concent r ic velocity

(MV) is used, the result ing equat ion was: Load = 7.5786 MV 2 –

75.865 MV + 113.02 (R 2 = 0.979; SEE = 3.77 % 1RM).

2.0

1.5

1.0

0.5

0.020 40 60

Load (% 1RM)

MPV = 0.00003 Load2 - 0.0204 Load + 1.889

R2 = 0.98; SEE = 0.06 m s -1; N = 1.596

Mean

Pro

pu

lsiv

e V

elo

cit

y (

m s

-1)

80 100

Fig. 1 Relationship between relative load ( % 1RM) and MPV directly

obtained from 1 596 raw data derived from the 176 incremental tests

performed in the BP exercise. Solid line shows the fi t ted curve to the data,

and the dot ted lines indicate limits within which 95 % of predictions will

fall.

Table 1 Changes in mean propulsive velocity (m · s − 1 ) at tained with each

relative load, from init ial test (T1) to retest (T2), after 6-wk of training, in the

bench press exercise.

Load ( % 1RM) T1 T2 Diff erence

(T1 – T2)

30 % 1.33 ± 0.08 1.33 ± 0.08 0.00

35 % 1.24 ± 0.07 1.23 ± 0.07 0.01

40 % 1.15 ± 0.06 1.14 ± 0.06 0.01

45 % 1.06 ± 0.05 1.05 ± 0.05 0.01

50 % 0.97 ± 0.05 0.96 ± 0.05 0.01

55 % 0.89 ± 0.05 0.87 ± 0.05 0.01 *

60 % 0.80 ± 0.05 0.79 ± 0.05 0.01

65 % 0.72 ± 0.05 0.71 ± 0.05 0.01

70 % 0.64 ± 0.05 0.63 ± 0.05 0.01

75 % 0.56 ± 0.04 0.55 ± 0.04 0.01

80 % 0.48 ± 0.04 0.47 ± 0.04 0.01

85 % 0.41 ± 0.04 0.40 ± 0.04 0.01

90 % 0.33 ± 0.04 0.32 ± 0.04 0.01

95 % 0.26 ± 0.03 0.25 ± 0.03 0.01

100 % 0.19 ± 0.04 0.18 ± 0.04 0.00 *

* Does not exact ly coincide with T1-T2 due to the shown values being the result of

rounding to two decimal places. Values are mean ± SD (N = 56).

0.95

0.85

0.75

0.65

0.55

0.00 0.05 0.10 0.15

V1RM (m s-1)

Mean

Test

Velo

city

(m

s-1

)

0.20 0.25

y = 0.3145x + 0.7084

r = 0.27; P < 0.01; N = 176

0.30

Fig. 2 Correlat ion between mean velocit ies at tained with the 1RM load

(V 1RM ) and mean test velocity.

Dow

nlo

ad

ed

by: U

NIV

ER

SID

AD

PA

BL

O O

LA

VID

E.

Co

pyrig

hte

d m

ate

ria

l.

VELOCIDAD DE EJECUCIÓN COMO MEDIDA DE LA INTENSIDAD

Este carácter de esfuerzo define la relación entre lo realizado y lo realizable.

Un mismo estímulo externo (x) podrá representar un carácter de esfuerzo diferente en distintos momentos o situaciones.

Debemos conocer el nivel de exigencia que ha supuesto dicho estímulo para cada sujeto en cada momento.

“Carácter de esfuerzo” González-Badillo (1995)

parte, Izquierdo-Gabarren et al. (8) compararon los efectos de 8

semanas de entrenamiento de fuerza al fallo con un

entrenamiento sin llegar al fallo en un grupo de piragüistas de alto

nivel. Para ello, dividieron aleatoriamente al grupo de deportistas

en distintos sub-grupos: repeticiones al fallo (RF), repeticiones sin

llegar al fallo (NRF). Todos los piragüistas realizaron el mismo

entrenamiento de fuerza, con la única diferencia de que el grupo

RF realizó 10RM en cada serie mientras que el grupo NRF realizó

5 repeticiones (es decir, la mitad de volumen). Después de las 8

semanas de entrenamiento, se observó que el grupo NRF mejoró

más la RM y la potencia máxima en press de banca, así como la

potencia media y máxima de palada en remo en comparación

con el grupo RF.

De esta forma, parece que entrenar con la mitad de las

repeticiones posibles es más adecuado para la mejora del

rendimiento físico pues, como poco, tiene los mismos efectos

que utilizar repeticiones al fallo (cuando no más), y esto es

probablemente debido, entre otros factores, al menor grado de

fatiga que produce en el organismo. Sin embargo, llegados a este

67

A partir de la mitad de las repeticiones, la pérdida de velocidad es notable. Nótese que en la última r epetición posible la

velocidad es muy próxima a la asociada a la RM (ver Capítulo 2).

Figura 5.2 Pérdida de velocidad dentro de una serie de sentadilla

0,400

0,525

0,650

0,775

0,900

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26

Velo

cid

ad

med

ia p

rop

uls

iva (m

/s)

Nº repetición

Effects of velocity loss during resistance training on athleticperformance, strength gains and muscle adaptations

F. Pareja-Blanco1, D. Rodrıguez-Rosell1, L . Sanchez-M edina2, J. Sanchis-M oysi3,4, C. Dorado3,4, R. M ora-Custodio1,

J. M . Ya~nez-Garcıa1, D. M orales-Alamo3,4, I . Perez-Suarez3,4, J. A. L. Calbet3,4, J. J. Gonzalez-Badillo1

1Physical Performance & Sports Research Center, Pablo de Olavide University, Seville, Spain, 2Studies, Research & SportsM edicine Center, Government of Navarre, Pamplona, Spain, 3Department of Physical Education, Las Palmas de Gran CanariaUniversity, Las Palmas de Gran Canaria, Spain, 4Research Institute of Biomedical and Health Sciences ( IUIBS) , Las Palmas deGran Canaria University, Las Palmas de Gran Canaria, SpainCorresponding author: Fernando Pareja-Blanco, Centro de Investigacion en Rendimiento Fısico y Deportivo, Universidad Pablo deOlavide, Ctra. de Utrera km 1, 41013 Seville, Spain. Tel.: + 34 653121522; Fax: + 34 954 348 659; E-mail: fparbla@gmail.com

Accepted for publication 23 February 2016

We compared the effects of two resistance training (RT)programs only differing in the repetition velocity lossallowed in each set: 20% (VL20) vs 40% (VL40) onmuscle structural and functional adaptations. Twenty-twoyoung males were randomly assigned to a VL20 (n = 12)or VL40 (n = 10) group. Subjects followed an 8-weekvelocity-based RT program using the squat exercise whilemonitoring repetition velocity. Pre- and post-trainingassessments included: magnetic resonance imaging, vastuslateralis biopsies for muscle cross-sectional area (CSA)and fiber type analyses, one-repetition maximum strengthand full load-velocity squat profile, countermovement jump(CM J), and 20-m sprint running. VL20 resulted in similar

squat strength gains than VL40 and greater improvementsin CM J (9.5% vs 3.5%, P < 0.05), despite VL20performing 40% fewer repetitions. Although both groupsincreased mean fiber CSA and whole quadriceps musclevolume, VL40 training elicited a greater hypertrophy ofvastus lateralis and intermedius than VL20. Trainingresulted in a reduction of myosin heavy chain I IXpercentage in VL40, whereas it was preserved in VL20. Inconclusion, the progressive accumulation of muscle fatigueas indicated by a more pronounced repetition velocity lossappears as an important variable in the configuration ofthe resistance exercise stimulus as it influences functionaland structural neuromuscular adaptations.

The adaptive response to resistance training (RT)

depends on several variables that configure the resis-

tance exercise stimulus such as loading magnitude,

number of sets and repetitions, exercise type and

order, rests duration, and movement velocity (Spier-

ing et al., 2008; Sanchez-M edina & Gonzalez-

Badillo, 2011). I t has been shown that velocity loss

and metabolic stress considerably differ depending

on the actual number of repetitions performed in an

exercise set in relation to the maximum number that

can be completed (Sanchez-M edina & Gonzalez-

Badillo, 2011). Although some studies (Rooney

et al., 1994; Ahtiainen et al., 2003; Drinkwater et al.,

2005) suggest that performing repetitions to failure

may be necessary to maximize muscle mass and

strength, others seem to indicate that similar, if not

greater, strength gains and improvements in athletic

performance can be obtained without reaching mus-

cle failure (Folland et al., 2002; Izquierdo et al.,

2006; Izquierdo-Gabarren et al., 2010). I t has been

hypothesized that RT eliciting high levels of fatigue,

as it occurs in typical body-building routines, may

induce greater strength adaptations due to an

enhanced activation of motor units and secretion of

growth-promoting hormones (Schott et al., 1995;

Schoenfeld, 2010). However, definitive evidence is

lacking and the controversial results found in the lit-

erature clearly emphasize theneed to conduct further

research on this topic.

Experiments with isolated human muscle fibers

(M ogensen et al., 2006), as well as in vivo human

studies (Aagaard & Andersen, 1998; Sanchis-M oysi

et al., 2010) have shown that a high proportion of

type I I muscle fibers or myosin heavy chain (M HC)

I I isoforms is associated with high levels of forcepro-

duction during fast muscle contractions. Interest-

ingly, most studies have shown that the percentage

of type I IX fibers is reduced following a RT program

based on repetitions to failure (Staron et al., 1991;

Andersen & Aagaard, 2000; Campos et al., 2002;

Andersen et al., 2005). Nevertheless, a study by

Harridge et al. (1998) showed that maximal isomet-

ric strength (voluntary and electrically evoked) can

be significantly increased without a reduction in the

1

Scand J M ed Sci Sports 2016: : –doi: 10.1111/sms.12678

ª 2016 John Wiley & Sons A/S.

Published by John Wiley & Sons Ltd

Objetivo: Comparamos los efectos de dos programas de entrenamiento de fuerza(RT) que sólo difieren en la pérdida develocidad : 20% (VL20) vs. 40% (VL40) en las adaptaciones estructurales y funcionales del músculo.

Métodos: Veintidós varones jóvenes fueron asignados aleatoriamente a un grupo VL20 (n = 12) o VL40 (n = 10). Lossujetos siguieron un programa de RT basado en velocidad de 8 semanas usando el ejercicio de sentadillas mientras semonitorizaba la velocidad de repetición. Las evaluaciones previas y posteriores a la capacitación incluyeron: resonanciamagnética, biopsias del vasto lateral para análisis del tipo de fibra, análisis de tipo de fibra, fuerza máxima de una repeticióny perfil de sentadilla de carga máxima, salto de contramovimiento (CMJ) y Carrera de 20 metros en sprint.

Resultados:VL20 tuvo similares ganancias de fuerza en squat que VL40 y mayores mejoras en CMJ (9.5% vs 3.5%, P<0.05), a pesar de VL20 realizando un 40% menos repeticiones. Aunque ambos grupos tuvieron un aumento de la seccióntrasversal y del volumen total del músculo cuádriceps, el entrenamiento con VL40 provocó una mayor hipertrofia de vastolateral e interno que VL20.