The purposes of the present study were: (1) to compare four different metho
ds of calculating mechanical power in running on the basis of comparable da
ta over a wide range of running velocity; (2) to examine the linearity of t
he relation between mechanical power as calculated with the four methods an
d running velocity. Eight runners participated in the investigation (height
: 1.82 +/- 0.03 m, body mass: 81.05 +/- 4.69 kg). A Kistler force platform
registered all components of the ground reaction force (1000 Hz) during one
foot ground contact, which was additionally video taped using two high-spe
ed video cameras running at 120 Hz. Four different methods were used to cal
culate mechanical power. Two methods determined the mechanical power due to
the work done on the athletes' center of mass and two were calculated from
the motion of the athletes' segments. The four different methods provided
different relations between mechanical power and running velocity. The calc
ulations on the basis of kinematic data cannot be recommended to determine
efficiency of movement. The methods based on ground reaction force measurem
ents revealed significant linear relations (r(2) = 0.90, r(2) = 0.84) betwe
en running velocity and mechanical power. (C) 2000 Elsevier Science Ltd. Al
l rights reserved.