Efficiency of Gait

• Efficiency of gait regards the speed of walking but also for how long they can continue
• Maintaining efficiency of gait is dependent on preventing:

  • vertical displacement - more muscles moving up and down = more energy expenditure
  • horizontal displacement - more muscles moving side to side = more energy expenditure
• Determinants of gait efficiency:

  • pelvic rotation
  • pelvic obliquity
  • knee flexion in stance
  • ankle mechanism
  • foot mechanism
  • valgus angulation of the knee
• Pelvic rotation:

  • the rotation of the pelvis allows for a longer step to be taken without the need for vertical displacement
• Pelvic obliquity:

  • by slightly dropping your pelvis on the same side of the foot moving forward, it allows for a larger step to be taken without the need for vertical displacement
• Knee flexion:

  • works during stance phase but a larger work during swing phase
  • focus on knee flexion at beginning of stance phase - reduces vertical displacement
  • without knee flexion at beginning of stance phase, the pelvis would arc up and down, so knee flexion removes that
• Ankle and foot mechanisms:

  • prevent vertical displacement whilst taking longer steps
  • projecting your heel out allows dorsiflexion of the ankle during initial heel contact allows for a slight increase in leg length
  • without this you'd have to flex your knee or hips to reach the ground with your foot
  • at the end of stance phase, plantarflexion allows for a longer leg length to push off from

  
• Vulgas angulation of the knees:

  • knees closer together
  • enables people to walk with minimal horizontal displacement
• • at slower speeds, theres higher energy expenditure
  • as speed increases, energy expenditure decreases
  • once 1.5 metres per second (average walking speed), efficiency is at its best
  • once speed increases past this, efficiency decreases as energy expenditure increase again