.................................................................................................................................... 7 Introduction .............................................................................................................................. 8 Running Shoe Theory on the Cause of RRIs ....................................................................... 11 Theory Development ................................................................................................ 11 High Impact Forces (Kinetics) ................................................................................. 13 Abnormal Subtalar Motion (Kinematics) ................................................................. 15 Application of Running Shoe Theory ................................................................................... 17 Cushioning ................................................................................................................ 18 Motion-Controlling .................................................................................................. 19 Barefoot Running Theory on the Cause of RRIs ................................................................ 21 Theory Development ................................................................................................ 21 Atrophy of Intrinsic Foot Musculature ..................................................................... 23 Diminished Somatosensation ................................................................................... 24 Unnatural Running Form .......................................................................................... 26 Application of Barefoot Running Theory ............................................................................ 28 vii Improve Intrinsic Foot Muscle Action ..................................................................... 28 Facilitate Somatosensation ....................................................................................... 29 Promote Better Running Form ................................................................................. 31 Future Research Directions ................................................................................................... 32 Conclusion ............................................................................................................................... 33 References ............................................................................................................................... 34 CHAPTER 3: EVALUATING THE BIOMECHANICAL EFFECTS OF ALTERED PLANTAR CUTANEOUS SENSATION ON THE ACQUISITION OF A BAREFOOT RUNNING STYLE ........................................................................................................... 41 Abstract ................................................................................................................................... 4