Custom formed orthoses in cycling.

Area of Science:

• Sports Biomechanics
• Orthotics and Prosthetics

Background:

• Custom foot orthoses (CFOs) are frequently prescribed to athletes.
• Their systematic effects on cycling biomechanics, particularly during the power phase, require further investigation.

Purpose of the Study:

• To assess the effects of prescribed in-shoe CFOs on hip adduction, knee abduction, and tibial internal rotation during the cycling power phase.
• To determine if CFOs produce systematic or subject-specific biomechanical changes in cyclists.

Main Methods:

• A before-and-after crossover study design was employed.
• Twelve competitive cyclists used their prescribed CFOs or no orthoses during stationary cycling.
• Three-dimensional biomechanical data were collected using an 8-camera Vicon system and analyzed with 2-way ANOVA.

Main Results:

• No systematic effects of CFOs on cycling biomechanics were observed.
• A trend towards reduced tibial internal rotation was noted (P<0.072).
• Significant subject-specific biomechanical effects were identified (P<0.05), with three distinct knee movement patterns observed.

Conclusions:

• Currently prescribed CFOs do not systematically alter cycling biomechanics in competitive cyclists.
• CFOs can induce significant subject-specific biomechanical modifications, influenced by rearfoot and/or forefoot wedges.
• An individualized approach to orthotic prescription, considering the forefoot-rearfoot relationship, is recommended.