Table 1 Biomechanical adaptations of load carriage to potentially optimize metabolic cost and minimise injury risk
Potential positive adaptation | Biomechanical changes with load | Potential negative adaptation |
|---|---|---|
• Transfer energy from proximal to foot segment [64] • ↑ Energy stored as elastic energy [65] | ↑ Ankle negative power mid-stance [6] |  |
• Accelerates leg into extension to ↑ energy transferred to proximal segments [64] | ↑ Knee positive power late stance [6] | |
• ↑ Hip extension deceleration of trailing thigh segment for preparation into hip flexion swing [66] • Transfers energy from trunk to trailing stance limb to prepare into swing [64] | ↑ Hip negative power late stance [6] | |
• ↑ Elastic energy recovery [67] • Avoid excessive vertical COM excursion and maintain ground reaction force alignment to stance limb [68, 69] | ↑ Leg stiffness [70] | |
• Architecture of triceps-surae muscle tendon unit makes it an efficient force generator [65] | Small role for inter-joint work redistribution [71] | |
|  | ↑ Hip adduction late stance [6] | • Asymmetrical loading on knee soft tissues [72] |
↑ Knee and ankle flexion mid-stance [6] | • ↑ COM vertical excursion [70] • ↑ Patellofemoral joint compression pressure and ↑ Achilles tendon compression [73, 74] |