THEORY AND PRACTICE IN APPLIEDSPORT SCIENCE

Johnny Nilsson

The Swedish School of Sport and Health Sciences

Graduate student lecture at theLatvian Academy of Sport Education

April 2011

Aim

To present different examples how Sport Science can beintegrated with practice in sport education and training

To briefly describe different types of research methods related to sport science

Lecture design

1. Wrestling

2. Physical activity & neuro-motor training in physical education & sports

3. Cross-country skiing and Alpine skiing

4. Wheelchair racing

Laboratory of Applied Sport Science

The Swedish School of Sport and Health Sciences

WRESTLING

Analysis of physical demands in Graeco Roman style wrestling

World Championships 1998 & 1999

• Work time profile

• Blood lactate accumulation

• Rated Perceived Exertion RPE

Arbetsperioder

Viloperioder

Blodlaktathalt

Högintensivt aerobt

arbete & anaerob

belastning

Work time intervals

Rest time intervals

• Blood lactate accu-mulation

• High intensity aerobic work load

”Dubbel metabolism”

Absolut muskelspänning & blodocklusion Träning

High RPE in forearm muscles

Specific endurance strength training for

”grip” muscles

Wrestling=”double metabolism”; Local muscular enduranceGeneral aerobic endurance

• ”Local” endurance

• General endurance

• Leg muscle endurancestrength to push opponent forward

• High mean power level

Power= Force • velocity

P= F • v

Powerboxen

P= F • s/t

Utvecklingsarbete i

syfte att träna

critical power

The Power Box

Prototype 1

Prototype 2

Prototype 3

• Specific leg muscle endurance strength

• Simultaneous feedback

• Logging of training performance

•Parterrlyft

•Poängutdelning

•Lyftproblematik

• The lift capacity is important for performancein wrestling

• Muscular power: P=F•v ; Absolute strength and speed

kg

A/D PC Printer

Power-lift

The Power Lift

The Power Lift

• Specific lift power training

• Direct feeback on relevant parameters

• Logging of training

performance

Kvalitativ och kvantitativ teknikanalys; ”The NEAT system”

Qualitative analysis of technique learning

• Digital video & video analysis software

• Feedback on important details in movement technique

Physical Activity & neuro-motor trainingin Physical education & Sports

Grammar school

Junior high

Junior high

High school

Motor activity – children play – motor development

R= BreakT=Theory lessonI= Physical education lesson

Level: Grammar Junior High High

Heart rate (beats/minute)

Motor activity lesson Route & motor activity choice

Bird perspective

• To study spontaneousand directed motoractivity

• To study and developmotor functions during play

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

0

5

10

15

20

Lektionstid 36 min

Fp: x

Lek i motorikbana

Glid

a/ru

tcha

Stå

ende

/balan

s

Arm

styr

ka/b

alan

s

Kullerb

ytta

Kry

pa

Klätte

rgån

g

Klättr

a

Pen

dla

i lina

Tram

petth

opp

Förbe

rede

lse

Gån

g/ba

lans

Vila

/sto

pp

Trans

port

An

tal uppre

pnin

gar

under

lektion

0 1 2 3 4 5 6 7 8 9 10 11 12 13

0

5

10

15

20

Fp: x

Lek i motorikbana

Glid

a/ru

tcha

Stå

ende

/balan

s

Arm

styr

ka/b

alan

s

Kullerb

ytta

Kry

pa

Klätte

rgån

g

Klättr

a

Pen

dla

i lina

Tram

petth

opp

Förbe

rede

lse

Gån

g/ba

lans

Vila

/sto

pp

Trans

port

Pro

cent av tota

ltid

• Quantity of training = necessity for motor development

• How many repetitions are acceptable for a well designed lesson

• Quality analysis

Skiing playground

Combination training: Motor skill & aerobic training

Volleyball

GIH Motor Lab

Stimulate spontaneousmotor activity

Screening test for teachers a o

Prototype 1 Prototype 2

The Music Motor Plate

• Motor development with music

• Stimulate people with low motor function to perform music

• Increase motor activity among children and adults

• Pedagogical dual action

• Combined motor & aerobic training

Cross-country skiing and Alpine skiing

Cross-country skiing – Double poling

• Which is the technique of the best skiers?

• Is there a typical co-ordination pattern?

• Effektive ways to test and train double poling

• Need for precise feedback

Hur stakar eliten ? (Nilsson & Holmberg)

Kinematik, EMG-mönster och muskelaktiveringsgrad vid stakning på snö

EMG-pattern, activation level and joint angular displacement during doublepoling

Recorded muscles Electrogoniometers

• Elite cross-country skiers• Double poling at different speeds• Video recording

Three step rocket

Step 2Step 1

Step 3

Beginning of thrustEnd of thrust

The winner of the Wasa race

Hög

Kontroll-

nivå

CNS

Låg

Konroll-

nivå

PNF

Ryggmärg

Receptorer

CENTRAL PROCESSOR

MOVEMENT PATTERNGENERATION

Effectorsignal

EMGsignal

•Time of activation

•Activation level

Further studies on DP technique

2D and 3D movement analysis

• Pole forces• Joint torques• EMG

Raw recording from elgons and EMG & video sequence

Hip angle

Knee angle

EMGRectusfemoris

Ext.

EMGRectusabdominis

Flex.

Three step rocket

Hip

Shoulder

Elbow

Sequential activationOrder of EMG peaks

The double poling ergometer

The feeling and technique close to DP on skis

• Need for testingdouble poling (DP)performance

• Need for a trainingapparatus giving detailed feedback

A

B

Po

wer

(W) 150 W

176 W

83 W

Whole body Trunk & arms Arms

A B C

Testing for a weak link in the three step rocket

A more detailed knowledge of power production in DP

30 s peak och 30 s mean &

30 s peak och 6 min. mean

Correlation between 30p and 30mean

R2 = 0.98

0

100

200

300

400

100 150 200 250 300 350 400 450

30peak

30m

ean

Correlation between 30peak and 6mean

R2 = 0.87

0

50

100

150

200

250

100 150 200 250 300 350 400 450

30peak

6m

ean

Strong correlation between short timePower production and endurance power

Specific strength important for DP endurance ?

B

A

AB

Krav på

absolut

power

Power-kvoten - ” komfort styrka”

Teorin om betydelsen av

stor styrka för hög

medeleffekt

Typ I

Typ IIa

Typ IIx

Sty

rka

fö

r p

ow

er

Intensitet

Strength vs EnduranceStr

eng

thfo

r po

wer

Theory: The importance of high max srength for high mean power and low relative load

Mean powerdemand

EMG och ledvinklar vid telemarkskidåkning och

barmarksövningar för telemark (Nilsson & Haugen)

•När och i vilken omfattning aktiveras främre lår-

muskulaturen (VL) i telemarkskidåkning ?

•Ledvinkelamplitud och ledvinkelhastighet ?

•Hur specifika är barmarksövningarna; imitationshopp,

knäböj, plyometriska hopp och slide-board ?

Alpine Skiing - Telemark Skiing

• When and how much are the quads (VL) activatedin Telemark skiing and dryland exercises?

• Strength specificity in: -Muscle action-Joint angle amplitude-Angular velocity

•Fp: 5 manliga åkare i Norges telemarkslandslag

•EMG VL: timing och amplitud

•Ledvinkelrörelser; amplitud och vinkelhastighet

•Datasampling: logger med interface till dator

• Elite male Telemark skiers

• Electromyography EMG

• Electrogoniometry

• Insole pressure

7 8 9 10 11 12 13 14 15

100110120130140150160

EM

G V

L (

au)

Time (s)

7 8 9 10 11 12 13 14 15

60

80

100

120

140

160

Knee a

ngle

(degre

es) 7 8 9 10 11 12 13 14 15

020406080

100120140

Foot-

sole

pre

ssure

(au)

Raw recording

Normalized plot

Specificitet

•Amplitud

•Muskelaktionstyp

•Vinkelhastighet

• Telemark skiing

• Telemark jumps

• Barbell squats Muscle action

1

0

10

20

30

40

50

60

70

80

90

100

110

120 *

*

*

Barbell

squats

Telemark

jumps

Telemark

skiing

E1E1E1 F1F1F1

Net

knee a

ng

ula

r am

plit

ude (

deg

rees)

1

0

20

40

60

80

100

120

Barbell

squats

Telemark

jumps

Telemark

skiing

M

ean E

MG

am

plit

ude

(P

erc

ent)

1

0

20

40

60

80

100

120

140

160

180

**

*

*

F1 E1 F1 E1

Barbel

squats

Telemak

jumps

Telemak

skiing

F1 E1

Knee a

ngula

r velo

city

(degre

es p

er

second)

• Joint angle amplitude

• Angular velocity

• EMG activation level

ECCON - Apparatus for test and training of eccentric and concentric leg muscle strength

• Bilateral force recording

• Direct force feedback

• PC data logging

Wheelchair racing

Aim

• Learn more about the muscle coordination patternin wheelchair racing

• Learn more about speed dependence in muscle coordination and EMG amplitude

Competition technique - muscle activity

•Elektromyography - EMG

Tric. Brachii

Bic. Brachii

Pectoralis major

Latissimus dorsi

•Elbow angle

•Trunk angle

•Speed registration: Laser camera + speed logger

•Video filmning

Wheelchair movement cycle

60 70 80 90 100

0

40

80

120

160

85 1007565

EM

G B

ic b

r dxt

Relativ hastghet %

60 70 80 90 100

075

150225300375450

EM

G T

ric b

r dxt 60 70 80 90 100

0306090

120150180

EM

G P

ect dxt

60 70 80 90 100

0306090

120150180

EM

G L

ats

dxt

Speed versus EMG amplitude

The End