EDUCATION COURSES. Stride. Initial Swing (high knee) Mid stance Toe off Mid swing Initial contact

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1 EDUCATION COURSES RUNNING ANALYSIS Our purpose is performance enhancement. Improving speed and acceleration is the key to success in most ground-based sports. The ability to run from m as fast as possible is something that we need to be able to assess and improve upon each session. As running speed increases, stance phase and flight times approach each other until the stance phase becomes shorter than the swing phase in sprinting. As speed increases, the pelvic, hip and knee joints increase there range of motion to decrease the vertical shift in the centre of gravity. This increasing range must be absorbed by increasing muscle forces acting over these joints, thus faster runners require more flexibility and eccentric muscle strength. Sprinters maintain weight bearing on the mid-foot which places the foot in slight plantar flexion at impact. Dorsiflexion occurs directly after initial contact and the heel does not touch the ground at any time. The sprinting gait cycle can be divided into stance phase, swing phase and float phase. The first half of the stance phase is concerned with force absorption (pronation), whereas the second half is responsible for propulsion (supination). Pronation and supination is the body's way of absorbing shock and allowing the foot to work as a lever. However, excessive motion in either direction can be very problematic if not controlled. Pronation necessitates a flexible foot for shock absorption, whereas supination necessitates a rigid foot for propulsion. Initial contact Absorption Stance Propulsion Stride Double Float Initial Swing (high knee) Swing Terminal Swing (rip phase) Double Float Effects of pronation and supination up the kinetic chain Pronation Supination Sagittal Frontal Transverse Sagittal Frontal Transverse Lumbosacral Extension Lateral flexion Protraction Extension Lateral flexion Retraction Pelvis Mid stance Toe off Mid swing Initial contact Ant. Translation & elevation Forward Ant. (opp side) Translation (opp side) & depression Rear Hip Flexion Adduction Internal Extension Abduction External Knee Flexion Abduction Internal Extension Adduction External Ankle PF-DF Internal DF-PF External Subtalar joint PF Eversion Adduction DF Inversion Abduction Midtalar joint DF Inversion Abduction PF Eversion Adduction

2 In weight bearing there is a 1:1 realtionship between the degree of supination relative to tibial external and pronation relative to tibial internal In sprinting, a certain amount of pelvic movement (, anterior-posterior and lateral tilt) is required. However, excessive movement in any of these planes due to poor control of the stabilizing muscles, leads to less effective transmission of forces through the pelvis and less efficient movement. Lack of stability in one plane may predispose to development of problems in another plane. The most common abnormalities are excessive anterior and lateral tilt. Sprinting Mechanics Significant Variables for Success Forward lean of the body Greater stride rate Decreased support time Greater upper-leg al speed during the support phase (quick high knee pull) Greater lower-leg al speed at touchdown and greater backward foot speed relative to the body at touchdown (quicker rip cycle) Short foot-to-body distance at touchdown (foot strike beneath hip) Deficiencies Muscles that are used frequently can shorten and become dominant in a motor pattern. If a muscle predominates in a motor pattern, its antagonist may become inhibited and cause a muscle imbalance. Muscles are divided into two types: Postural and Phasic. Postural muscles are used for standing and walking and are activated constantly to fight the forces of gravity, therefore have a tendency to shorten and become tight. Phasic muscles are used for propulsion and typically remain in an elongated state. However, weak phasic muscles might allow excessive motion to occur at the joints upon which they act. Common tight and inhibited muscles in running Postural (tendency to shortness and tightness) 1. Gastroc-soleus (predominately soleus) 2. Rectus femoris 3. Iliopsoas 4. Tensor fascia lata 5. Hamstrings 6. Short thigh adductors (Adductor Brevis & Obturator Externus) 7. Quadratus lumborum 8. Piriformis 9. Sartorius Phasic (tendency to weakness and inhibition) 1. Tibialis anterior 2. Peroneals 3. Vastus medialis 4. Long thigh adductors (Adductor Longus, Magnus & Gracilis) 5. Gluteus max, med, min

3 Large front cycle (foot too far ahead of the body at touchdown) This overemphasizes the upper- and lower-leg extension, and poor lower-leg speed at touchdown and results in a breaking action. This can result from poor upper-leg strength and/or a body position that is too vertical resulting in increased support phase time and decreased stride rate. Arm swing If the arms swing higher than shoulder level; there is a tendency for the athlete s strides to be shorter. Tense shoulders or arms will cause the arms to move more slowly, consequently slowing down the leg speed. Excessive Pronation (ankle dorsiflexion, forefoot abduction and subtalar eversion) Occurs at the subtalar joint and causes internal of the entire lower limb during weight bearing and increases the ground reaction forces on the medial aspect on the foot which can lead to joint abnormalities (including exotoses, hallux valgus, sesamoid pain, and callus and corn build up). Causes increased load on the medial longitudinal arch, plantar fascia and plantar musculature. The gastroc-soleus complex and tibialis posterior may eccentrically contract harder and longer in order to decelerate of the leg and pronation of the foot (this in turn can contribute to tendinopathy in the Achilles and posterior tibialis tendons). Leads to increased internal of the tibia, increasing the risk of lateral sublaxation of the patella, muscle imbalance of the quadriceps, and tightening of the iliotibial band all of which can lead to patellofemoral joint dysfunction (changes in alignment, tendinopathy) Leads to overuse of the tibialis posterior muscle and long flexor tendons, this can contribute to traction on the periosteum and bending of the tibia. As these muscles become increasingly fatigued due to excessive pronation, the tibia is subjected to greater impact and susceptible to stress fractures. Stress fractures of the metatarsals and sesamoids are also common due to uneven weight distribution and excessive movement with pronation. Excessive Supination (ankle plantarflexion, forefoot adduction and subtalar inversion) May occur at the subtalar joint to compensate for structural foot abnormalities, or as a result of weakness of the antagonist pronating muscles (peroneals: longus, brevis & tertius), or as a result of spasm or tightness of the supinating musculature (tibialis posterior & the gastrocnemius-soleus complex). The supinated foot may be less mobile resulting in poor shock absorption, and a tendency for stress fractures (tibia, fibula, calcaneus, and metatarsals [esp. 4 th & 5 th ]). Lateral instability of the foot and ankle is associated with excessive supination and results in an increased incidence of sprains of the ankle and foot. Due to the increased lateral stress on the lower limb, the iliotibial band becomes tighter and bursitis may occur at the femoral condyle. Excessive Anterior Pelvic Tilt Increased anterior tilt while running may increase the length and tension of the hamstrings and abdominal muscles. It is precipitated by poor pelvic control (abdominals, glut med and min, hamstrings and external hip rotators) in combination with tightness of the hip flexors. The external rotators of the hip become tight as they work excessively to provide pelvic stability to compensate for the reduced contribution by the gluteal muscles, and can lead to an abducted angle of gait. Increased anterior pelvis tilt with hip extension leads to increased lumbar lordosis and strain on the lumbar apophyseal joints and sacroiliac joints. Knee flexion is also greater at foot strike and mid-stance, which increases the eccentric load across the extensor mechanism of the knee (can lead to patella tendinopathy). With

4 greater knee flexion the patella will be compressed against the femur with greater force predisposing to patellofemoral joint syndrome. Excessive anterior tilt can be bi- or uni-lateral. Excessive Lateral Pelvic Tilt Occurs due to poor control of hip abductors and adductors of the weight-bearing limb allowing the contra-lateral hip to drop during its swing phase. Places excessive strain and can cause inflammation of the lateral hip structures, adductors, tensor fascia lata, iliotibial band, lateral knee and lumbar spine. Anterior pelvic tilt which causes increased gluteal muscle length and therefore, reduced force of contraction, leads to increased lateral pelvic tilt. Asymmetrical Pelvic Tilt Due to the large number of muscles that attach to the pelvis, asymmetry may be caused by: Tight/shortened muscles Inco-ordinate weakened muscles Structural abnormalities (e.g. leg length discrepancy, scoliosis) These occur primarily as an adaptation to a previous injury, and are exacerbated by running Video Analysis - Swinger Software SIDE VIEW Knee to hip level (Cue: Pick-up your knees) Hands cheek to cheek, 90 degrees Proper arm action can significantly enhance force production and force transmission. Correct arm action helps to counteract al forces; this enhances dynamic postural control and neuromuscular efficiency. (Cues: Pick-up your hands, Kick your elbow back, Drive your elbow down and back). Running on balls of feet The foot should remain dorsi-flexed at all times during the running cycle, except when it is in contact with the ground. (Cue: Pick-up your toe, and run on the ball of foot) Fully extend back leg while in drive phase The emphasis is on triple extension, ankle plantar flexion, knee extension, hip extension, lumber spine neutral. This will ensure optimum force production and efficiency. (Cue: Drive your knee, which will extend your leg) Watch for a full stride between 10-20m marks. (Cue: Need to stretch hamstrings more) First step not in front of hip (Cue: Push back on the initial strides) Foot strike below hip (Cue: Pull the leg underneath) Neutral head position (Cue: Eyes forward) Lean forward, 45 degree angle Optimum posture allows for optimum force production. (Cue: Keep the chest open, Straight back, Lock the back into place) Foot cycling up to butt (Cue: Kick your butt when up high) A lot of athletes leave their leg down (low) during the swing through, particularly tall athletes, which makes their leg turnover very slow. BACK VIEW Not running on a tight rope (Cue: Start with feet shoulder width and keep them that way) Eliminate back/trunk (Cue: Keep hips and shoulders square) Eliminate excessive foot pronation/supination (Cue: Visit a podiatrist) FRONT VIEW Eliminate trunk (Cue: Keep hips and shoulders square) Eliminate arms crossing midline of body (Cue: Arms forwards and backwards)

5 Eliminate knee crossing midline of body (Cue: Knees forwards and backwards) You need to remember that no one can run perfectly, so you need to be coaching them at all times. It takes a long time to become a good speed and agility coach. Start coaching HARDER today.