THIS IS THE EASIEST WAY TO REMEMBER THE BIOMECHANICS. HOPE IT IS USEFUL.

1. RUNNING
BIOMECHANIC
S & INJURIES
KAVITA JOSHI (MPT 2ND YR)

2. • PRONATION
Ankle dorsiflexion
Subtalar eversion
Forefoot abduction
• SUPINATION
Ankle plantarflexion
Subtalar inversion
Forefoot adduction

3. Differences Between Running And Walking
• Increased velocity
• Increased GRF
• Decreased COG with increased speed
• Decreased BOS
• Requires more ROM of LE
• Requires greater eccentric muscle contraction
• Float phase
• No double stance phase
• Decreased stance phase & increased swing phase
• Overlap of swing phase rather than stance phase
• Initial contact varies, depending on speed

4.  GAIT CYCLE
1. NORMAL WALKING
2. RUNNING
• At Maximum Running Speed: Stance Phase- 22% & Swing Phase ses.
-1ST HALF OF STANCE: Force Absorptn- Pronation (Eccentric- Jt.control)
- 2ND HALF OF STANCE : Force Generatn- Supination (Concentric-Acceleratn-
Propulsn)
STANCE PHASE- 60%
SWING PHASE- 40%
STANCE
PHASE-
30%- 40%
SWING
PHASE-
60%
FLOAT
PHASE

6. STANCE PHASE

7.  INITIAL CONTACT TO FOOT FLAT (LOADING)
1) IC :
KINEMATICS
Foot- Supination- Functional varus (8° -14°)
STJ: Inversion (GRF – lateral border)
PELVIS: Slight Anterior Tilt (10°)
HIP: Abd. + ER (5 ° -10°) & Flexed (30°)
KNEE: Add. + ER & Flexed (10°)

8. • 2) FOOT FLAT:
KINEMATICS
Shock Absorption Events Occurs Compensating For Laterally Directed GRF In IC.
ANKLE: Pronation
STJ: Eversion (GRF- medial border of foot)
HIP: IR + Add. + Flexion 35° (GRF- Ant.)
KNEE: IR + Abd. + Flexion 45° (GRF- Post.)
 Contralateral pelvic drop ( 5°): GLUTEALS
KINETICS OF 1 & 2
• Each of these motions is controlled by eccentric muscle activity which
helps to dissipate the ground reaction forces.

9. FOOT FLAT TO HEEL OFF (MID-STANCE)
KINEMATICS
 Transition From Shock Absorption To Propulsion
 Ankle Moves Toward Maximal DF (20°) To Allow Forward Motion
Of The Tibia & COM To Pass Over The Stance Leg.
 ANKLE: Pronation to Supination (FEMUR & TIBIA ER)
 HIP & KNEE : Flexion to Extension (Assisting COM)
 Peak rearfoot eversion occurs: 10°
 peak forefoot abduction occurs: 5°

10.  EXCESSIVE PRONATION
Strain On Structures – Pronation
PF, TP mus., & Intrinsic Foot Mus.
Increases Medial GRF
> Motion At The Knee, Hip, And Pelvis
Load On Ligaments & Mus. Providing
Proximal Control
INJURIES
 EXCESSIVE C/L PELVIC
DROP, HIP ADD.
 EXCESSIVE ANTERIOR
TILTING OF THE PELVIS
 EXCESSIVE SUPINATION

11. HEEL OFF TO TOE OFF (PROPULSION)
KINEMATICS:
Following Heel Off, The Foot Continues To Supinate
STANCE LIMB: ER
ANKLE: STJ: INVERSION ( 10°)
HIP: Maximal Extensn (0-10°)
KNEE: Flexion
By toe off: Rearfoot inverted : 10° , Forefoot adducted : 5°

12. KINETICS:
Acceleration of the stance limb is provided through plantar flexion at
the ankle, produced by the gastrocnemius and soleus complex.
Same gastrocnemius and soleus activity, along with the tibialis
posterior, continues to actively assist supination of the foot, and
maintain its function as rigid lever.
Passively, rigidity of the foot is supported by the "windlass
mechanism" (i.e. increased tension of the plantar fascia due to
extension of the meta·tarsals which pulls the calcaneus and metatarsal
heads together’)

14. SWING PHASE

15.  INITIAL SWING – MIDSWING : KINETICS & MATICS
Body Is Thrust Into The 1st “FLOAT” Phase.
 KNEE: The line of GRF at toe-off passes posterior to the knee
joint, which flexes the knee as the body is propelled forward.
- This knee flexion is resisted by eccentric contraction of the
rectus femoris, which also acts concentrically with the iliopsoas
to flex the hip and advance the limb forward.
 HIP:- Hip abducts in relation to events that occur on the
opposite side.
- After the float phase, the opposite limb strikes the ground
and the hip abductors are activated to stabilize the pelvis.
- As the swinging limb advances forward, pelvic rotation
pushes the hip into Abduction.

16. PELVIS: Pelvic Rotation of the swing leg helps to place the stance leg
in relative ER and helps initiate more supination. This motion is
resisted by the hip adductors, which remain active throughout this
phase.
ANKLE: Throughout this phase, the Anterior Tibialis acts
concentrically to DF the ankle. This action is more important in
walking to clear the foot as the limb advances forward. In running,
the amount of knee flexion that occurs will negate the importance of
dorsiflexion to allow foot clearance.

19. TERMINAL SWING: KINETICS & MATICS
Body Is Thrust Into The 2nd “FLOAT” Phase.
 At this point, the swinging limb is preparing to contact the ground.
 Knee: extension occurs rapidly as a result of forward momentum and
contraction of the rectus femoris.
 Hip:
- flexion terminates and extension begins under concentric control of the
hamstrings and gluteus maximus
- During terminal swing, the hip adducts as the foot prepares to contact the
ground along the line of progression. The hip adductors concentrically bring the
femur toward the midline during this portion of swing phase. They continue to
be active throughout the stance phase to stabilize the LE, and thereby, function
throughout the entirety of the running gait cycle.

20.  Ankle:
- As the foot prepares to contact the ground, the gastrocnemius-soleus
begins to contract.
- The anterior tibialis remains active throughout the swing phase and into a
portion of the stance phase
- At initial contact, co-contraction of the anterior tibialis and gastrocnemius-
soleus creates a stable foot for weight acceptance .
- At this point, one complete gait cycle has occurred and the patterns are
repeated as the next cycle begins.

21. LUMBAR SPINE: LORDOSIS + LAT.FLEXn
SAME SIDE
PELVIS: ANTERIOR TILT + ELEVATION SAME
SIDE
HIP: IR +ADD.
KNEE: IR + ABD. (VALGUS)
STJ: EVERSION
FOREFOOT: ABDUCTION
FOOT - PRONATION
LUMBAR SPINE: LORDOSIS + LAT.FLEXn
OPPOSITE SIDE
PELVIS: ANTERIOR TILT + ELEVATION OPP.
SIDE
HIP: ER +ABD.
KNEE: ER + ADD. (VARUS)
STJ: INVERSION
FOREFOOT: ADDUCTION
FOOT - SUPINATION

22. RUNNING INJURIES
 FOOT & ANKLE INJURIES
Tendinopathies & stress fractures
Plantarfasicitis
Fat pad contusions
Posterior tibial tendinopathy
Peroneal tendinopathy
Tarsal tunnel syndrome
Metatarsalgia
Neuromas

23. Lateral Ankle Sprains
Achilles Tendinopathy
Retrocalcaneal Bursitis
Knee Injuries: Patellofemoral Pain & Iliotibial Band Syndrome
Hip & Pelvic : Gluteus Medius Tendinosis
Spine: Spondylolisthesis

24. REFERENCES
- DONALD NEUMANN
- PEGGY HOUGLAM
- KARIM KHAN