Download - Roald Bahr
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Muscle Injury Prevention
Prof. Roald Bahr MD PhDHead, Aspetar Sports Injury & Illness Prevention ProgrammeChair, Oslo Sports Trauma Research Center Chief Medical Officer & Department Chair, Olympiatoppen & Norwegian Olympic Training Center
1. Establishing the extent of the injury problem:
• Incidence• Severity
2. Establishing etiology and mechanisms of sports injuries
3. Introducing a preventive measure
4. Assessing its effectiveness by repeating step 1
Idea for prevention?
IBV; Eyjolfsson & Jonsson, 2000
Pilot data – eccentric strength training
1992 1993
Num
ber
of h
amst
rings
str
ains
0
1
2
3
4
5
6
7
8
IBV; Eyjolfsson & Jonsson, 2000
Pilot data – eccentric strength training
1992 1993 1994 1995 1996 1997 1998 1999 2000
Num
ber
of h
amst
rings
str
ains
0
1
2
3
4
5
6
7
8
Idea for prevention?
Test it!
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The exercise prescription
Week
1
2
3
4
Sessions/week
1
2
3
3
Sets and Repetitions
2 x 5
2 x 6
3 x 6-8
3 x 8-10
5-10 3 3 x 12+10+8
10+ 1 3 x 12+10+8
Mjølsnes et al. Scand J Med Sci Sports, 14: 311-317, 2004
cons ext ecc flex isom flex 90 isom flex 60 isom flex 30
Knee
tor
que
(Nm
)
-10
-5
0
5
10
15
20
25
30 Nordic hamstring Hamstring curl
Eccentric strength training Delayed onset muscle soreness
1 2 3 4 5 6 7 8 9 10
DO
MS
(0
-10
)
0
1
2
3
4
5
6
7
8
9
10
Nordic hamstring Hamstring curl
The Iceland-Norway study- the OSTRC hamstring strain prevention program
Arnason et al. Scand J Med Sci Sports. 18:40-8, 2008
3-component program:
1 Warm-up stretchGoal: Stretch towards maximal ROM
2 Flexibility trainingGoal: Increase maximal ROM
3 Eccentric strength trainingGoal: Increase strength
Arnason et al. Scand J Med Sci Sports. 18:40-8, 2008
Results – stretching
Stretching Control
Ham
strin
g in
jury
inci
denc
e (p
er 1
000
h)
0,0
0,1
0,2
0,3
0,4
0,5
0,6
0,7
2000 2001
3
Arnason et al. Scand J Med Sci Sports. 18:40-8, 2008
Results – strength training
Total Match Training
Ham
strin
g in
jury
inci
denc
e (p
er 1
000
h)
0,0
0,5
1,0
1,5
2,0
2,5
3,0Training groupNo training
RR: 0.35p<0.001
Petersen et al. Am J Sports Med 2011 Aug 8 [Epub ahead of print]
Petersen et al. Am J Sports Med 2011 Aug 8 [Epub ahead of print]
Overall injury risk
Control Intervention
Stra
ins
per
100
play
er s
easo
ns (
%)
0
2
4
6
8
10
12
14
aRR=0.29 (95%CI 0.15-0.57)
Number neededto treat:
13
Control Intervention
Stra
ins
per
100
play
er s
easo
ns (
%)
0
10
20
30
40
50
Petersen et al. Am J Sports Med 2011 Aug 8 [Epub ahead of print]
New injuries
Control Intervention
Stra
ins
per
100
play
er s
easo
ns (
%)
0
2
4
6
8
10
12
14
aRR=0.41 (95%CI 0.18-0.93)
Number neededto treat:
25
aRR=0.14 (95%CI 0.04-0.51)
Recurrent injuries
Number neededto treat:
3
Take home message
If you enjoy risk taking, you should NOT include
Nordic Hamstrings in yourtraining program
”Intellectuals solve
problems; geniuses prevent them”
Albert Einstein(1879 – 1955)
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The Oslo Sports Trauma Research Center has been established at
the Norwegian School of Sport Sciences through generous grants from the Royal Norwegian Ministry of Culture, the South-Eastern Norway Regional Health Authority, the International Olympic Committee, the Norwegian Olympic
Committee & Confederation of Sport, and Norsk Tipping AS