Biomechanical Analyses of Road Cycling

Abstract

A practical and realistic biomechanical analysis reveals various important features of road cycling, starting from the following. For a racing bike traveling fast, about 80 percent of the work the cyclist does will go in overcoming air resistance. Therefore, road cyclists do prefer to use a so-called aerodynamic position. Their “aero position” inevitably implies an anterior tilt of 15°-20° of their pelvis. In the optimal aerodynamic position, 20° anterior pelvic tilt results in 7,5 % increase of the lengths of hamstrings biceps femoris (long head) and semimembranosus, and 6 % decrease of the length of quadriceps muscle part rectus femoris. The observed increases and decreases of lengths of these muscles in aero position may lead to respectively hamstrings passive insufficiency, and rectus femoris muscle active insufficiency, as these muscles are now likely to shift away from their plateau region of optimal force (= 100 %). Such imminent muscle insufficiencies are reflected in “thigh injuries” “quadriceps and hamstring strains”, as described in cyclists. Using a “gravity seat” (J. Mackenroth, 2013) possibly neutralizes some anterior pelvic tilt. To restore optimal muscle force however, Electro Vibro Stimulation (EVS) is strongly recommended.