Vibrations in cycling, state of the art and future outlook

Engineering of Sport 15 - Proceedings from the 15th International Conference on the Engineering of Sport (ISEA 2024) Road cycling is an endurance sport that requires athletes and enthusiasts to cycle for long time. Thus, comfort plays an important role in the design of bicycles and cycling garments. Vibrations represent one of the most common cause of discomfort. Famous cycling competitions, such as the Paris-Roubaix, are characterized by uneven road surface that induces vibrations, thus increasing the difficulty of the race. On a physiological level, Sperlich et al., demonstrated that the presence of vibrations in cycling lead to an increased oxygen uptake at higher loads. Besides downgrading performances, long-term exposure to vibrations can lead to disorders. Therefore, it is of fundamental importance to investigate vibration and their transmission to the bicycle and the cyclist. This work aims to review the state of the art in the field of cycling vibration and identify the need for future studies. </p

Benchmarking rolling resistance of bicycle tyres on a laboratory treadmill

Engineering of Sport 15 - Proceedings from the 15th International Conference on the Engineering of Sport (ISEA 2024) Tyre rolling resistance is considered to be one of the major performance determining factors for vehicles in general but bicycles specifically. In cycling, a trend to wider tyres is given in order to provide comfort to the athlete. The impact of tyre dimensions, thread pattern and tyre pressure to rolling resistance is hence subject for ongoing discussion. In this study, a selection of 15 different tyres from one manufacturer (Wilderness Trail Bikes, Marin County, USA) was examined in terms of their rolling resistance on smooth surfaces. An alternative method to the usual drum test rigs was used, a stationary laboratory treadmill, which in future can also be used to investigate rolling resistance on uneven road surfaces. </p

Impact loads when jumping on indoor climbing mats

Engineering of Sport 15 - Proceedings from the 15th International Conference on the Engineering of Sport (ISEA 2024) Bouldering is rope-free climbing on large boulders in nature or on artificial climbing facilities. In contrast to sport climbing, bouldering is done without a belay and reaches a maximum height of 4.0 to 4.5 metres, as specified in the EN 12572 Part 2 standard. In bouldering, the challenge is to complete a climbing route, usually consisting of four to eight climbs. A bouldering hall offers a variety of different levels of difficulty for everyone, from beginners to competitive athletes, the opportunity to venture to the limits of their capabilities. In addition to the physical requirements, a certain amount of creativity and skill is often needed to solve the bouldering problem. In order to protect the boulderer as much as possible from injury while practising the sport, fall protection devices are installed under the wall. These range from small crash pads, which are used for climbing on the rock because they are easy to move and can therefore be placed quickly in the important places, to fully laid mat systems, which are permanently installed in bouldering halls. The aim of this study was to investigate the impact loads on the lower extremities as well as the human body’s center of mass when jumping onto different types of foam mats used in indoor bouldering facilities. </p

The use of geometrical simplification to model natural fibre composites.

Engineering of Sport 15 - Proceedings from the 15th International Conference on the Engineering of Sport (ISEA 2024) Performance benchmarking allows the sports engineer to determine a deeper understanding of the properties and performance of the equipment being studied. The rationale for this is often to enable the replacement of some aspect of the design or improvement of the materials or a combination of these. For the sport of polo high ranked players prefer traditional, natural material constructions and the replacement of these with advanced composites or metallic blends is being met with much resistance. One of the overarching factors driving the need to develop materials in this sport is due to governmental mandates and the reduction in forests that produce the appropriate genus of cane, calamus manau rattan, desired by the highest ranked players. The early results of surveys being taken by the polo community are indicating that the biggest challenge to innovation of the mallet is due to a combination of the factors,traditionality and subjectivity. The natural cane used in the shafts performs unlike any other material and because of this the feel and response of the equipment is likewise unique. As well as this there is also the consideration that the forcesthat can be applied by the player to the ball are below those that might otherwise cause injury to the horse. In this work we deconstruct the cane in order to model the geometry in an effort to identify what enables the unique response of the natural composite. Once this is complete the adaptation of a predictive modelling approach previously developed to predict the mechanical response of both thermoset and thermoplastic composites is considered. Mechanical test results are also compared </p

A sensor-based test methodology to investigate the effect of vibrations on the cyclist

Engineering of Sport 15 - Proceedings from the 15th International Conference on the Engineering of Sport (ISEA 2024) Road surface induced vibrations during cycling impact general parameters such as comfort, fatigue or control. Skilled cyclists appear to adopt their riding style to different surface conditions by e.g. adjusting position, the way of grasping the handlebar or the pedalling style. Investigating the effect of vibrations on a cyclist in the field is limited by the need of invasive measurement equipment and by the difficulty to repeat a test without minute deviations. To this end, replicating relevant road surface patterns in a controlled environment is indicated. In this pilot study, a laboratory stationary treadmill is used to simulate two different road surfaces to observe, by mean of wearable sensors, the effect of vibrations on a cyclist. </p