11 research outputs found
Effect of cadence selection on peak power and time of power production in elite BMX riders; a laboratory based study.
The aims of this study were to analyse the optimal cadence for peak power production and time to peak power in bicycle motocross (BMX) riders. Six male elite BMX riders volunteered for the study. Each rider completed 3 maximal sprints at a cadence of 80, 100, 120 and 140revs·min-1 on a laboratory Schoberer Rad Messtechnik (SRM) cycle ergometer in isokinetic mode. The riders’ mean values for peak power and time of power production in all three tests were recorded. The BMX riders produced peak power (1105±139W) at 100revs·min-1 with lower peak power produced at 80revs:min-1 (1060±69W, (F(2,15)=3.162; p=.266; η2 =0.960), 120revs·min-1 (1077±141W, (F(2,15)=4.348; p=.203; η2 =0.970) and 140revs·min-1 (1046±175W, (F(2,15)=12.350; p=0.077; η2 =0.989). The shortest time to power production was attained at 120revs·min-1 in 2.5±1.07s. Whilst a cadence of 80revs:min-1 (3.5±0.8s, (F(2,15)=2.667; p=.284; η2 =0.800) 100revs:min-1 (3.00±1.13s, (F(2,15)=24.832; p=.039; η2 =0.974) and 140revs:min-1 (3.50±0.88s, (F(2,15)=44.167; p=.006; η2 =0.967)) all recorded a longer time to peak power production. The results indicate that the optimal cadence for producing peak power output and reducing the time to peak power output are attained at comparatively low cadences for sprint cycling events. These findings could potentially inform strength and conditioning training to maximise dynamic force production and enable coaches to select optimal gear ratios
Variability in Laboratory vs. Field Testing of Peak Power, Torque, and Time of Peak Power Production Among Elite Bicycle Motocross Cyclists
The aim of this study was to ascertain the variation in elite male bicycle motocross (BMX) cyclists' peak power, torque, and time of power production during laboratory and field-based testing. Eight elite male BMX riders volunteered for the study, and each rider completed 3 maximal sprints using both a Schoberer Rad Messtechnik (SRM) ergometer in the laboratory and a portable SRM power meter on an Olympic standard indoor BMX track. The results revealed a significantly higher peak power (p <= 0.001, 34 ± 9%) and reduced time of power production (p <= 0.001, 105 ± 24%) in the field tests when compared with laboratory-derived values. Torque was also reported to be lower in the laboratory tests but not to an accepted level of significance (p = 0.182, 6 ± 8%). These results suggest that field-based testing may be a more effective and accurate measure of a BMX rider's peak power, torque, and time of power production
Optimizing the breakaway position in cycle races using mathematical modelling
In long-distance competitive cycling, efforts to mitigate
the effects of air resistance can significantly reduce
the energy expended by the cyclist. A common method to
achieve such reductions is for the riders to cycle in one large
group, known as the peloton. However, to win a race a cyclist
must break away from the peloton, losing the advantage
of drag reduction and riding solo to cross the finish line
ahead of the other riders. If the rider breaks away too soon
then fatigue effects due to the extra pedal force required
to overcome the additional drag will result in them being
caught by the peloton. On the other hand, if the rider breaks
away too late then they will not maximize their time advantage
over the main field. In this paper, we derive a mathematical
model for the motion of the peloton and breakaway
rider and use asymptotic analysis techniques to derive analytical
solutions for their behaviour. The results are used to
predict the optimum time for a rider to break away that maximizes
the finish time ahead of the peloton for a given course
profile and rider statistics