One of the most important aspects of high performance cycling is the best fit between rider and bike. Developing a proper bike fit requires conducting many biomechanical assessments due to the need to match a myriad of bike geometries and human anthropometric variables. One of the primary bike-rider system measurement parameters for power and pedal efficiencies is the cleat placement and alignment. The purpose of this study was to examine the effects of moving the cleats towards the heel on peak power outputs and pedal efficiencies using a Computrainer (CT) and 2D video analysis. Ten competitive male cyclists participated in the study consisting of tests for peak power (PP) outputs and pedaling efficiencies among two positions of cleats; toe (TP) and heel (HP). No significant differences in peak power outputs were reported between TP and HP (p = .827). Significant differences (p = .027) did exist, however between each condition within the SpinScan (SS) pedal efficiency test. Results from the 2-D video analysis indicate that there exists a difference in ankling patterns between the TP and HP during the first 50 percent of the power phase and the last 50 percent of the recovery phase of the pedal stroke (p = .000 and .001 respectively Based on the results of this study, further research into the longitudinal effects of training in this area are warranted. / School of Physical Education, Sport, and Exercise Science

The purpose of this study was to quantify the EMG activity of selected lower limb muscles during cycling, and to define the relationship between pedal shaft width and muscular involvement. This study has particular significance to the female cyclist who by virtue of pelvic width may have a less efficient pedalling force, or an imbalance of applied muscular force. Variables analyzed were hip, knee, ankle range of motion (ROM), biceps femoris(BF), vastus lateralis(VL), rectus femoris(RF), and vastus medialis(VMO) muscle activity. Significant differences among three different pedal shaft widths were determined through use of repeated measures oneway ANOVA, Newman-Keuls post hoc test. The hip ROM, biceps femoris, and vastus medialis EKG activity results of the present study appeared to indicate that different pedal shaft widths had an effect on changes in the ROM and EMG activity. This study indicated that the hip ROM values increased with an increase in the pedal shaft width. In contary, an increase in pedal shaft width significantly decreased the muscle activity in the vastus medialis while two inch pedal shaft width significantly decreased the muscle activity in the biceps femoris. / School of Physical Education

This investigation evaluated the cardiorespiratory responses to three rider positions while undergoing maximal cycle ergometry. The positions were determined by the position of the hands on the handlebars and the posture of the upper body: upright (UP), and drop position (DP) with conventional racing handlebars, and an aerodynamic tuck (AT) using Scott DH time-trial handlebars. Ten well-trained (mean V02max=60.7 ± 3.63 ml*kg-1*min-1) cyclists underwent three randomly assigned separate maximal ergometry tests using each position. Variables of interest were: heart rate (RR), systolic blood pressure (SBP), diastolic blood pressure (DBP) , rate pressure product (RPP) , oxygen consumption (V02), pulmonary ventilation (VI)' ventilatory equivalent (V1/V02), respiratory exchange ratio (RER), ratings of perceived exertion (RPE) , and total time to test termination (TT). These variables did not differ significantly between rider positions at each stage of the maximal exercise tests but did change in response to increasing workloads. These results suggest that rider position does not enhance or diminish the cardiorespiratory response to maximal cycle ergometry as the responses to each position are similar. / Master of Science

This thesis studies the dynamics and stability of some bicycles. The dynamics of idealized bicycles is of interest due to complexities associated with the behaviour of this seemingly simple machine. It is also useful as it can be a starting point for analysis of more complicated systems, such as motorcycles with suspensions, frame flexibility and thick tyres. Finally, accurate and reliable analyses of bicycles can provide benchmarks for checking the correctness of general multibody dynamics codes. The first part of the thesis deals with the derivation of fully nonlinear differential equations of motion for a bicycle. Lagrange’s equations are derived along with the constraint equations in an algorithmic way using computer algebra.Then equivalent equations are obtained numerically using a Newton-Euler formulation. The Newton-Euler formulation is less straightforward than the Lagrangian one and it requires the solution of a bigger system of linear equations in the unknowns. However, it is computationally faster because it has been implemented numerically, unlike Lagrange’s equations which involve long analytical expressions that need to be transferred to a numerical computing environment before being integrated. The two sets of equations are validated against each other using consistent initial conditions. The match obtained is, expectedly, very accurate. The second part of the thesis discusses the linearization of the full nonlinear equations of motion. Lagrange’s equations have been used.The equations are linearized and the corresponding eigenvalue problem studied. The eigenvalues are plotted as functions of the forward speed ν of the bicycle. Several eigenmodes, like weave, capsize, and a stable mode called caster, have been identified along with the speed intervals where they are dominant. The results obtained, for certain parameter values, are in complete numerical agreement with those obtained by other independent researchers, and further validate the equations of motion. The bicycle with these parameters is called the benchmark bicycle. The third part of the thesis makes a detailed and comprehensive study of hands-free circular motions of the benchmark bicycle. Various one-parameter families of circular motions have been identified. Three distinct families exist: (1)A handlebar-forward family, starting from capsize bifurcation off straight-line motion, and ending in an unstable static equilibrium with the frame perfectly upright, and the front wheel almost perpendicular. (2) A handlebar-reversed family, starting again from capsize bifurcation, but ending with the front wheel again steered straight, the bicycle spinning infinitely fast in small circles while lying flat in the ground plane. (3) Lastly, a family joining a similar flat spinning motion (with handlebar forward), to a handlebar-reversed limit, circling in dynamic balance at infinite speed, with the frame near upright and the front wheel almost perpendicular; the transition between handlebar forward and reversed is through moderate-speed circular pivoting with the rear wheel not rotating, and the bicycle virtually upright. In the fourth part of this thesis, some of the parameters (both geometrical and inertial) for the benchmark bicycle have been changed and the resulting different bicycles and their circular motions studied showing other families of circular motions. Finally, some of the circular motions have been examined, numerically and analytically, for stability.