Author Identifier

Paul F. J. Merkes

https://orcid.org/0000-0001-7309-2717

Date of Award

2020

Document Type

Thesis

Publisher

Edith Cowan University

Degree Name

Doctor of Philosophy

School

School of Medical and Health Sciences

First Supervisor

Associate Professor Chris Abbiss

Second Supervisor

Dr Paolo Menaspà

Abstract

The majority of road cycling races finish with a sprint and as such sprints are a key determinant of success. Surprisingly, the scientific literature on this specific topic is scarce, with limited to few studies describing the characteristics of road cycling sprinters and the demands of road sprinting. Cyclists’ sprinting velocity, which is mostly influenced by power output and aerodynamic drag (CdA) is critical to performance outcomes. However, to date, there is very limited research specifically examining how to maximise road sprint velocity. Thus, the overall objective of the four studies outlined in this thesis was to manipulate CdA, physiology, and coaching cues to improve road sprint cycling velocity and performance.

The first study examined the validity of the Velocomp PowerPod, which calculates power output based on opposing/resistive forces experienced. When power output is known (using a direct force power meter), the Velocomp PowerPod is able to calculate a continuous CdA which was the reason why this study was included into this thesis. The research was split in to two separate studies: i) 12 recreational male road cyclists completed a power profile test (5-600 s); and ii) 4 elite male road cyclists completed 13 outdoor cycling training sessions. In both studies, power output of cyclists was continuously measured using both the Velocomp PowerPod and Verve Cycling InfoCrank power meters. The results showed that rolling resistance estimated by the Velocomp PowerPod (0.011 ± 0.0) was higher than what has been previously reported (0.006), which likely occurred due to errors in the subjective selection of road surface type in the device setup. This overestimation of rolling resistance increased the calculated power output, which was significantly greater than the power output measured by the Verve Cycling InfoCrank power meter in both study i and ii (27 to 39% and 16 to 49%, respectively). When rolling resistance was adjusted to previously reported values (0.006), the Velocomp PowerPod power meter was shown to be comparable to the Verve Cycling InfoCrank power meter during a controlled field test (−0.57 to 0.24%) but not dynamic training sessions (8.94 to 33.14%). Consequently, the Velocomp PowerPod power meter was not used in subsequent studies within this thesis.

The following two studies examined the effect of a seated, standing, and novel forward standing (lower and further forward head and torso) sprint position on performance. In study 2, eleven recreational male road cyclists rode 250 m at approximately 25, 32, and 40 km·h−1 and in each of the three positions. Riding velocity, power output, wind direction and velocity, road gradient, temperature, relative humidity, and barometric pressure were measured and used to calculate CdA using regression analysis. Sprinting in a forward standing position resulted in a 23% and 26% lower CdA, when compared with a seated and standing position, respectively. Furthermore, in contradiction with previous research no difference in CdA was observed between a seated and standing position. Additionally, despite no significant difference in CdA between the two test days a poor between-day reliability was observed. In study 3, eleven recreational male road cyclists performed a 14 s sprint in the three different sprint positions before and directly after a 10 min high-intensity lead-up. Peak and mean power output were similar between the forward standing (1126 ± 49 W and 896 ± 33 W, respectively) and both the seated (1043 ± 47 W and 857 ± 29 W, respectively) and standing positions (1175 ± 45 W and 928 ± 29 W, respectively). Collectively the results from studies 2 and 3 indicate that sprinting in the forward standing position may result in an increase in sprint cycling velocity of 5.6-6.5 km·h-1 and 2.1-5.1 km·h-1, when compared with the seated and standing sprint positions, respectively.

In study 4, 28 recreational road cyclists completed a two-week (3 sessions per week) sprint training intervention during which they received either i) visual and external focused verbal instructions, and positive feedback on their cycling sprint position (intervention group), or ii) neutral verbal instructions and feedback (control group). The combination of these coaching techniques did not enhance the training induced improvement in forward standing sprint performance. While improvements in peak (4%) and mean power output (3%), and peak torque (5%) were observed in both groups, it is unclear if these improvements are entirely due to the training programme because of the absence of a non-sprint training control group. This thesis has shown that sprinting in the novel forward standing sprint position could result in an increase of cycling velocity by approximately 5 km·h-1, when compared with more traditional sprint positions. In unaccustomed cyclists, sprint performance in this position might be further improved by a short two-week sprint training programme, however, further research is needed in this area. The results from this thesis have implications in training and tactical decisions of cyclists, coaches, and support staff aiming to be successful in competitive road cycling sprints.

Access Note

Access to Chapters 2 and 6 of this thesis is not available.

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