Objective-According to the literature, 30-70% of cyclists suffer from cervi
cal, dorsal, or lumbar back pain. This study was conducted to evaluate one
of the possible causes of low back pain and to suggest a solution by approp
riate adjustments to the bicycle.
Methods-Serial fluoroscopic studies were performed while cyclists sat on di
fferent types of bicycle (sports, mountain, and city). Pelvic/spine angles
were measured at different seat angles, and the related force vectors analy
Results-There was a tendency towards hyperextension of the pelvic/spine ang
le which resulted in an increase in tensile forces at the promontorium. The
se forces can easily be reduced by appropriate adjustment of the seat angle
-that is, by creating an anterior inclining angle. The findings of the biom
echanical analysis were then applied to a group of cyclists who were member
s of a cycling club and who complained of low back pain. After appropriate
adjustment of the saddle angle, most of the cyclists (> 70%) reported major
improvement in the incidence and magnitude of their back pain.
Conclusions-The incidence and magnitude of back pain in cyclists can be red
uced by appropriate adjustment of the angle of the saddle. It is important
that these findings be conveyed to cyclists, bicycle salesmen, trainers, an
d members of the general public who engage in cycling, in order to decrease
the prevalence of back pain.