Biomechanical correlates of exercise – areas of interest, endeavor, & contribution

1. Biomechanical correlates of exercise – areas of interest, endeavor, & contribution • Design/analysis of fitness programs • Design of fitness exercises • are exercises inherently safe and effective? • Exercises to avoid (e.g., deep knee bends, good morning exercise) • movements, forces, injury potential • Analysis of fitness exercises • are exercises being executed properly? • Design, selection, and analysis of fitness equipment • resistive equipment (e.g., thesis on situp ex equip) • aerobic equipment • Relative merits of exercise mode • Running shoes

2. Biomechanical aspects of aerobic exercise Adrian, p. 219 • Potential for injury increases with body weight • Airborne activities produce greater forces than non-airborne activities • Fast twisting movements of arm and upper trunk produce lower back reaction forces • Stress is inversely proportional to body surface area exposed • Joint shear stress is minimal if bones are aligned in a straight line • Knee joint stress is minimized it knee is alighted above the foot • Alignment of trunk above pelvis minimizes unbalanced stress of spine • Keep limbs close to trunk for maximum equilibrium • Longer limbs involve greater MOI, thus they are harder to move and accelerate • Joint reaction force increases with speed of angular movement • The taller person needs more time to perform an activity • Safety can be increased or decreased by modifying the intensity of the exercise

3. Biomechanics of Resistive exercises • Factors affecting force application • Force-velocity relationship • Strength-joint position relationship (combination of angle of pull and force/length relationship) • Should we provide the same degree of overload throughout the movement? If so, how do we do it?

4. Use of Cams in Ex Equipment:

5. Pelvic Girdle Balance

6. Compression and shear forces:

7. Spinal Flexion Exercises • Effect of • Anchoring feet? • Bending knees? • Placement of hands and arms? • Inclined board?

8. Back Extension Exercises to Avoid: Good morning exercise: Hyperextended back:

9. Recommended Extension Exercise Effect of speed on effects of exercise: Torque = Wd + MOI x ang acc

10. Effect of posture on lumbar compression force:

11. Torque while lifting: Recommendations: (1)bend knees and (2)keep weight close to hips

12. Knee Joint Structure: 25% of Alpine skiing injuries are ligament injuries Peripatellar pain (runner’s knee) caused by imbalance of stress on patella

13. Lower Extremity Misalignment: Q angle is larger in females due to Wider hip structure, increasing potential for PFPS (Patellofemoral pain syndrome)

14. Quadriceps Tendon and Patella Force Lines Compressive force at PFJ is ½ body wt during normal walking, and over 3 times bw during stair climbing Comp force increases as knee flexion Angle increases

15. Structure and tissues of shank and foot:

16. Subtalar axis:

17. Foot Pronation and Tibial Torsion:

18. Plantar Fascium:Plantar fascitis is 4th most common cause of pain among runners(1st – knee pain, 2nd – shin splints, 3rd- achilles tendonitis)

19. Arches of the Foot:

20. GRF while Running

21. Force vectors on different parts of foot

22. Rearfoot Movement During Running:

23. Types of running injuries

24. Example of Double Density Midsole:

25. Effects of Rear-foot Double Density Midsole on rearfoot position:

26. Effects of Rearfoot & Forefoot Double Density Midsole on takeoff angle: