I. Running Gait Cycle
Phases of Cycle:
1. Support Phase
2. Swing Phase
Running vs. Walking:
1. Walking - 2 periods of double support
60% of time in support phase
2. Running – 2 periods of double support
40% - 22% of time in support phase
3. Transition from walking to running:
5.6 mph (10:42 min/mile)
<50% time in stance phase and >50% time in swing phase
Four Subphases of Running Gait Cycle:
1. Initial Contact (IC)
2. Stance Reversal (StRev)
3. Toe Off (TO)
4. Swing Reversal (SwRev)
Two Actions of Running Gait Cycle:
1. Absorption (Abs) – body absorbs energy from ground or muscles
2. Generation (Gen) – Body generates energy from muscles and ground
1. IC1: joints flex and body weight is absorbed
2. StRev: COG is at lowest point then joints extend to generate power
3. TO: body is propelled off the ground
4. SwRev: legs generate power forward as joints flex then swing leg decelerates
and energy is absorbed as joints extend for contact
Muscle Action:
Each muscle group stretches eccentrically just before generating its burst of power concentrically.
1. Ground Contact energy absorption
Hip Extensors (Hamstrings, Gluteus Maximus and IT band)
Gastroc-Soleus eccentrically contract to prevent foot slap
Posterior tibialis maintains supination of foot
2. Stance Phase energy generation
Quadriceps and Gastroc-Soleus extend knee and push foot
Hip Abductors provide lift and support
3. Toe Off energy generation
Hip abductors and Quadriceps/Gastroc Soleus push to complete toe off
Hip Flexors start to pull leg up at end of toe off
4. Swing Phase energy generation
Hip flexors (psoas) swings leg forward
Anterior tibialis tendon dorsiflexes the ankle and foot
Quads extend lower leg swing out
5. Swing Phase energy absorption
Hamstrings slows down hip flexors at end of leg swing
IT Band slows down lower leg swing out
To more about evaluating your running for go to Running Evaluation
1. Head Position:
Keystone to body position
Head is held upright and is directly above shoulders
Focus eyes forward and ahead 10-20 meters, not down
2. Arm Carry:
Shoulders are square
Arms loose, not tight and elbows at a 90 degree angle
Arms move in rhythm with legs and synchronized with opposite leg
Arms move forwards not sideways or crossover body
3. Body Carriage and Position:
Body is erect with feet underneath body – forward lean only during acceleration
Shoulders are directly above hips with shoulders held back and chest extended outward
Trunk and pelvis perpendicular to the ground
Hips forward and square without rotation
Run with body weight over hips and feet underneath not behind
Forward motion is horizontal not vertical
4. Hip and Leg Motion:
Leg push-off is with the knee slightly bent and the ankle extended (Straight leg increases vertical motion)
Thigh is driven forward with the lower leg folded up underneath
Hips are driven forward not upward
Lower leg is extended forward at end of thigh drive “swing out” then driven downward and backwards “pawback”
Touchdown should be with the knee bent not straight
(straight leg causes braking force and deceleration of motion)
Center of Gravity is directly above foot on Support leg
5. Stride Length and Frequency:
Individualized based upon body size and flexibility
The faster the forward thigh drive the greater the stride length
(Tight hamstrings and weak hip flexors inhibit a fast forward thigh drive)
Overstriding slows momentum, increased stance time and more vertical
Understriding is inefficient and limits speed
6. Foot Strike:
Foot strike should be slightly in front of body
(the further it is away from COG the higher the braking forces)
Ground contact is made at midfoot to forefoot in supination
(heel strike is inefficient and increases braking forces)
Heel drops down after contact
Foot pronates as it progresses laterally to medially to push-off
The foot should be dorsi-flexed and carried through underneath the body
(foot flare-out is inefficient)
Bony Anatomy of the foot:
Hindfoot: Calcaneus and Talus bones
Midfoot: Medial longitudinal arch
Navicular bone (Keystone)
Tarsal bones
Forefoot: Metatarsal bones and Toes
Tendons and Ligaments of the foot:
Achilles Tendon: heel eversion and plantar flexion during toe off
Posterior Tibialis Tendon: supports medial longitudinal arch
creates Foot supination
Anterior Tibialis Tendon: supports foot during ground contact
Dorsiflexion of foot during swing phase
Long Plantar Ligament: Plantar Fascia and spring ligament
Supports medial longitudinal arch
Foot Biomechanics during running
Foot Types:
Cavus foot: fixed rigid high arch
Inability to absorb shock
Planus foot: flat foot – collapsed arch
Fixed: arch flat both loaded and unloaded
Flexible: arch normal unloaded but collapses when loaded
Foot Positions:
Hindfoot Valgus: calcaneal eversion
Hindfoot Varus: calcaneal inversion
Forefoot Adduction: toeing in
Forefoot Abduction: toeing out (too many toes sign)
Foot Actions:
Dorsiflexion: ankle and foot extending upwards during leg swing
Plantarflexion: ankle and foot extending downward as in toe off
Supination: calcaneal inversion and then forefoot adduction and plantarflexion
Pronation: calcaneal eversion
A downward migration of the midfoot then forefoot abduction and dorsiflexion
Hyperpronation:
Excessive or too early pronation. Lack initial brief supination. Weight is transmitted medially while weight is still on
hindfoot and midfoot. Weight bearing causes calcaneal eversion and collapse of the medial longitudinal arch. This
results in a cascade of biomechanical problems.
Factors contributing to hyperpronation:
1. Obesity – altered gait with rearfoot eversion and increased plantar pressure
2. Shoe wearing – increases foot pronation. High heels shortens Achilles tendon.
3. Hip abductor weakness – can lead to foot abduction (out toeing)
4. Genu valgum – (knocked knees) increases calcaneal eversion
5. Weak posterior tibialis – creates collapse of arches
6. Pes planus – flat feet (static or flexible)
Musculoskeletal Factors contirbuting to Hyperpronation:
1. Position of Calcaneus in gait cycle
Achilles tendon insertion and direction of action affects the position
Tendon inserts slightly lateral to midline
A tight tendon causes plantarflexion and calcaneal eversion
Causes a loss of height of the medial longitudinal arch
2. Posterior Tibialis Tendon (PTT) Strength
PTT is needed to maintain proper height of the navicular and talus bones
PTT weakness results in loss of height of the medial longitudinal arch
3. Height of Medial Longitudinal Arch
Collapse causes calcaneus to evert and foot to pronate excessively
Stretches the spring ligament and plantar fascia
Strectches and weakens the PTT
4. Forefoot position
Increased forefoot abduction increases force through 1st and 2nd rays
Results in Hallus Valgus (bunion) of 1st ray and metatarsalgia of 2nd ray
