Background
Objective
Research questions
-
What is the effectiveness of a coach supervised jump landing intervention program on the incidence of acute and overuse injuries to the lower extremity?
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What is the effect of a coach supervised jump landing intervention program on jump landing technique of individual athletes?
Methods
Study outline
Participants
Sample size
Recruitment
Intervention program
2 ×/week, 10 min. 1 min rest between repetitions | Technique/ Month 1 | Fundamentals/ Month 2 | Performance/ Month 3 | ||||||
---|---|---|---|---|---|---|---|---|---|
Week 1 | Co-contractions | 10 | L + R | Lying position | 15 | X-Hops | 6 | Cycles L + R | |
Wall Squat | 10 | Pelvic bridge | 10 | sec | Hop-Hop-Hold | 8 | L + R | ||
Lateral Jump and Hold | 8 | L + R | Repeated Tuck Jumps | 10 | L + R | Mattress jumps | 30 | sec | |
Front Lunges | 10 | Squat Jump | 10 | Single leg 90°* | 8 | L + R | |||
Step-Hold | 8 | L + R | Jump Single Leg Hold | 8 | Max Squat jumps-hold | 10 | L + R | ||
Week 2 | Co-contractions | 10 | L + R | Pelvic Bridge Single Leg | 10 | Crossover-Hop-Hop-Hold | 8 | L + R | |
Squat | 10 | Prone Bridge Hip (EK) Shoulder Flexion | 10 | L + R | Single Leg 4 Way Hop-Hold* | 3 | Cycles L + R | ||
Step-Hold | 8 | L + R | Side to Side Tuck Jump | 10 | sec | Single leg 90° Ball* | 8 | L + R | |
Walking Lunges | 10 | Lateral Hop & Hold | 8 | L + R | Step, jump up, down, vertical jump | 5 | L + R | ||
Lateral Jump and Hold | 8 | L + R | Hop & Hold | 8 | Max Squat jumps-hold | 10 | |||
Week 3 | Squat | 10 | Single Leg Pelvic Bridge* | 10 | L + R | Single Leg 4 Way Hop-Hold Ball* | 4 | Cycles L + R | |
Lateral Jump and Hold | 8 | L + R | Prone Bridge Hip extension | 10 | L + R | Single Leg 180° | 10 | L + R | |
Single Tuck Jump Soft Landing | 10 | L + R | Side to Side Tuck Jumps | 10 | L + R | Jump, Jump, Jump, vertical jump | 10 | sec | |
Lunge Jumps | 10 | Lateral Hops | 10 | sec | Mattress jumps | 40 | L + R | ||
Lateral Jumps | 10 | sec | Double leg 90° | 8 | L + R | Running, Jump down 1 legged, Jump | 8 | ||
Week 4 | Squat Jumps | 10 | Single Leg Pelvic Bridge Ball | 10 | L + R | Single Leg 180° | 10 | L + R | |
Lateral Jumps | 10 | sec | Prone Bridge Hip Opposed Shoulder Flexion | 10 | L + R | Jump, Jump, Jump, vertical jump | 15 | L + R | |
Double Tuck Jump | 8 | Lateral Hops with ball | 10 | sec | Running, Jump down 1 legged, Jump | 10 | |||
Broad Jump | 10 | L + R | Single Leg Lateral Hop-Hold | 5 | L + R | Lay-up ^ | 10 | ||
Scissor Jumps | 8 | Single leg 90° | 8 | L + R | Height jump ^ | 10 |
Measurements
Questionnaire
Jump landing technique
Front view (observers view) | ||||
---|---|---|---|---|
Criteria
|
Description
|
Observation
|
Measurement
|
Score
|
Maintaining 'balance'
- Loss of balance
| Lifting one foot or toes of both feet due to falling. | Observe complete jump | Loss of balance present or not | Loss of balance not present or doubt: 0 Loss of balance present: 1 |
- Centre of gravity displacement
| At first foot contact: Perpendicular through incisura jugularis | At maximal knee flexion determine the position of incisura jugularis (left/right) compared to perpendicular | Displacement not present or doubt: 0 Displacement left or right: 1 | |
Landing with 'both feet at the same time'
| Not simultaneous: obviously 2 contact times of the feet visible | Observe complete jump | Simultaneous landing present or not | Simultaneous landing present or doubt: 0 Simultaneous landing not present: 1 |
'Muscular control' during landing | Presence of eccentric control during landing, capacity to lower the body in a controlled manner (no side movements of the knee, no sudden stops) | Observe complete jump | Muscular control present or not | Muscular control present or doubt: 0 Muscular control not present: 1 |
'Genu varum' - 'Genu valgum' take-off
| Malalignement: valgus or varus position | At maximal knee flexion: perpendicular from SIAS to ankle (middle of malleoli) - Take-off | No varum or valgum: perpendicular goes through centre of patella | Perpendicular through patella or doubt: 0 Patella lateral from the perpendicular: (1 = varum) Patella medial from the perpendicular: (2 = valgum) |
'Genu varum' - 'Genu valgum' landing
| Malalignement: valgus or varus position | At maximal knee flexion: perpendicular from SIAS to ankle (middle of malleoli) - Landing | No varum or valgum: perpendicular goes through centre of patella | Perpendicular through patella or doubt: 0 Patella lateral from the perpendicular: (1 = varum) Patella medial from the perpendicular: (2 = valgum) |
'Position of feet'
| Feet at shoulder width. | At maximal knee flexion: Perpendicular trough centre of shoulders. | Perpendicular goes trough centre of malleolus internus and externus | Perpendicular through centre of malleoli or doubt: 0 Perpendicular not through centre of malleoli: 1 |
'Distance between knees' compared between initial contact and maximal knee flexion | Distance between knees at maximal knee flexion, 80-110% of distance between knees at initial contact. | Distance between knees at first foot contact and distance between knees at maximal knee flexion. | Range of 80%-110% difference. | Between 80%-11%: 0 Not between 80%-110%: 1 |
Hyperpronation - Hypersupination feet
Take-off
| Inside or outside movement of the malleoli compared to starting position. | Observe complete jump - Takeoff | Compare position feet with starting position. | Hyperpronation or -supination not present or doubt: 0 Hyperpronation or supination present: 1 |
Hyperpronation - Hypersupination feet
landing
| Inside or outside movement of the malleoli compared to starting position. | Observe complete jump - Landing | Compare position feet with starting position. | Hyperpronation or -supination not present or doubt: 0 Hyperpronation or supination present: 1 |
Side view
(right and left)
| ||||
Criteria
|
Description
|
Observation
|
Measurement
|
Score
|
Knee angle
- First foot contact
- Maximal knee flexion
| Knee angle at first foot contact Knee angle at maximal knee flexion | Ankle between trochanter major - caput fibulae (tractus iliotibialis) - mallolus externus | Degrees: | |
Hip angle
- First foot contact
- Maximal knee flexion
| Knee angle at first foot contact Knee angle at maximal knee flexion | Angle between trunk - trochanter major - caput fibulae (tractus iliotibialis) | Degrees: | |
Ankle angle
- First foot contact
- Maximal knee flexion
| Knee angle at first foot contact Knee angle at maximal knee flexion | Angle between caput fibulae (tractus iliotibialis) - malleolus externus - parallel with sole of foot | Degrees: | |
'shoulders above knees'
| Position at maximal knee flexion | Perpendicular through centre of shoulder (humerus head) | Perpendicular through caput fibula: 0 Perpendicular not through caput fibula: 1 | |
'knees not further than toes'
| Position at maximal knee flexion | Perpendicular through centre of knees | Perpendicular not further than toes: 0 Perpendicular further than toes: 1 | |
'forefoot landing and rolling to heel'
| Forefoot landing and rolling to heel | Observe complete jump | Pattern present or not | Pattern present or doubt: 0 Pattern not present: 1 |
Arm swing
| Obvious arm swing that contributes to the jump height | Observe complete jump | Arm swing present or not | Arm swing present: 0 Arm swing not present: 1 |