posted on 2010-11-15, 09:56authored bySimon G.S. Coleman
One of the most popular methods of assessment of power output during short-term
maximal of exercise is the Wingate Anaerobic Test (WAnT), but this test suffers from
serious conceptual limitations. Therefore, the first aim of this study was to investigate the
theoretical underpinnings and practical implementation of correct power measurement in
the WAnT. The second aim was to design and construct a pair of force pedals, and the
last objective was to use these pedals to analyse the force application and power output
of elite sprint cyclists during maximal ergometry.
The inertial and frictional characteristics of Monark ergometer flywheels were assessed
using 'run-down' techniques. Moments of Inertia of 0.411 (±0.001) and 0.396 (±0.002)
kg.m. 2 were found for the two Monark 864 ergometers measured, with the newer 814
ergometer possessing a value of 0.962 (±0.003) kg.m. 2 . Frictional torques of 0.0025
(±0.0030) to 0.1720 (±0.00 16) N.m. were found, depending on the attachments to the
flywheel and chainset.
These values were then utilised to correct the power outputs obtained during the WAnT.
Corrected powers were found to produce significantly (P<0.001) larger peak and mean
power outputs than those obtained using uncorrected methods. The methods used also
produced significantly different (P<0.01) corrected power outputs to those of Lakomy
(1986), who utilised an incorrect method of'acceleration-correction'.
The force pedals were found to be highly linear in calibration and force measurement, as
well as suitable for ergometer cycling. These were then used to test elite sprint cyclists
on a modified Monark ergometer.
The results of the sprint testing of cyclists found no overall significant difference between
power measured indirectly (at the flywheel) and that measured at the pedals. There were
significant differences between flywheel and pedal power outputs at high pedal velocity,
and this was attributed to large crank torques, in agreement with Sjøgaard (1978). Also
noted were differences in force application patterns between cyclists, indicating the use
of a variety of pedalling techniques.
It was concluded that inertial correction of the WAnT is mandatory for the accurate
measurement of power output, and that this needs to be based on sound mechanical
principles. This study has also shown that is possible to measure power accurately using
indirect methods. However, if the individual techniques of elite sprint cyclists are to be
examined in detail, it is necessary to utilise force pedals.