Abstract
Background: The visually guided braking has been investigated through information-based control approaches such as tau-dot strategy, which is mostly focused on how invariant optical variables regulate deceleration rate; however, the role of affordances on braking control is still unclear.
Aim: The aim of the study was to investigate whether cyclists take into account the perception of their action capabilities (affordances) during the braking task.
Material and Methods: Ten experienced cyclists (23.5 [+ or -] 0.5 years; 106.0 [+ or -] 24.0 kg; 186.5 [+ or -] 1.5 cm) were asked to brake while cycling in order to stop as close as possible to an obstacle and to avoid collisions. Cycling speed was manipulated by varying initial distances: low-speed 21.6m and high-speed 37m until the stationary obstacle. Brake strength was manipulated by adding weights on the bike: strong-brake, none; medium-brake, +5kg; weak- brake, +10kg; in order to alter the Maximum Deceleration (Dmax). Distinct Dmax values were expected to provoke change in the cyclists' action capabilities, which would affect the perception of possibilities for action (i.e., affordances). Bicycle motion was captured by GoPro camera (60 Hz) and analysis frame-by-frame (software Kinovea) was used to assess the cyclists performance. Ideal deceleration at braking onset (Dideal), Dideal relative to the Dmax (% Dmax) and Maximum velocity (Velmax) were submitted to brake vs. speed ANOVA-RM.
Results: Cyclists showed higher Velmax in high- than low-speed (p Keywords: visually guided braking, affordances, cycling
Aim: The aim of the study was to investigate whether cyclists take into account the perception of their action capabilities (affordances) during the braking task.
Material and Methods: Ten experienced cyclists (23.5 [+ or -] 0.5 years; 106.0 [+ or -] 24.0 kg; 186.5 [+ or -] 1.5 cm) were asked to brake while cycling in order to stop as close as possible to an obstacle and to avoid collisions. Cycling speed was manipulated by varying initial distances: low-speed 21.6m and high-speed 37m until the stationary obstacle. Brake strength was manipulated by adding weights on the bike: strong-brake, none; medium-brake, +5kg; weak- brake, +10kg; in order to alter the Maximum Deceleration (Dmax). Distinct Dmax values were expected to provoke change in the cyclists' action capabilities, which would affect the perception of possibilities for action (i.e., affordances). Bicycle motion was captured by GoPro camera (60 Hz) and analysis frame-by-frame (software Kinovea) was used to assess the cyclists performance. Ideal deceleration at braking onset (Dideal), Dideal relative to the Dmax (% Dmax) and Maximum velocity (Velmax) were submitted to brake vs. speed ANOVA-RM.
Results: Cyclists showed higher Velmax in high- than low-speed (p Keywords: visually guided braking, affordances, cycling
| Original language | English |
|---|---|
| Pages (from-to) | 94-95 |
| Number of pages | 2 |
| Journal | Brazilian Journal of Motor Behavior |
| Volume | 14 |
| Issue number | 4 |
| Publication status | Published - 1 Oct 2020 |