Precisely estimating and controlling the friction of a stone on ice is one of the abilities that is essential for good curling players. We propose here a new, simple, and player-friendly method for measuring friction using only stopwatches. As for friction control, it is known that friction must be modified by sweeping using brushes. It is widely performed not only to extend the stopping range of the stone but also to control the curls, although there is little scientific evidence to support the curl-controlling effects. We conducted a measurement to examine the effects, and we propose a potential method for assisting players to try similar kinds of quantitative studies themselves. The results we obtained suggest positive effects of the left–right asymmetric sweeping with 95% reliability for sweeping on the opposite half-side to assist curling.

This study examines the tribological properties of climbing shoe rubbers, challenging the common belief in the climbing community that softer rubbers are inherently grippier. This study investigates the mechanical and wear characteristics of climbing shoe rubbers by employing a high-precision modular mechanical testing environment (Bruker UMT TriboLab) and representative granite counter-surfaces. Key parameters, including surface roughness, Shore A hardness, interfacial adhesion, static and dynamic friction coefficients, and material wear patterns, were analyzed. The mechanical properties of each rubber compound were characterized through Shore A hardness testing and ball indentation–retraction tests, measuring indentation force, energy, and adhesive properties. Sliding friction tests, simulating real climbing conditions, were conducted to understand the tribological behavior of each rubber compound under different loads, further analyzing static and dynamic friction coefficients and wear characteristics. The findings of this study indicate that rubber performance is a convolution of several factors, including material hardness, surface roughness, and interfacial adhesion. Contrary to popular belief, softer rubbers did not consistently exhibit superior tribological characteristics. The findings of this study suggest that climbing shoe selection and design should consider a broader range of material characteristics beyond hardness, emphasizing the role of surface roughness and adhesion in determining overall frictional performance. This research offers valuable insights for the climbing community, providing methodologies to benchmark climbing rubber material characteristics.

Footwear used in competitive distance running has remained relatively unchanged in nature for decades. However, such technology has recently generated controversy with the introduction of so-called ‘supershoes’. Such footwear appear both aesthetically and functionally different to those used prior to their introduction and their arrival coincided with a spate of distance running world records being broken. The ten questions presented in this paper address a series of issues that relate to supershoes. These include their definition, what level of performance enhancement they provide and what impact they have had in competitive sport. Furthermore, it is explored how such technology is regulated and whether it should be considered fair. Via these questions, we hope to inform readers towards a greater understanding of this form of sports technology and highlight research and engineering gaps for future work.

This study aimed to explore the effect of two similar commercialized advanced footwear technology models differing mainly in their plate geometry (i.e., low and high curvature plate) on the running energetic cost in both non-fatigued and fatigued states. It also sought to determine their impacts on 3000-m performance. Twelve highly trained male athletes performed four 5-min trials (two advanced technology models, two trials). In each experimental session, athletes completed a 3000-m trial which was followed by a 5-min trial to test the running energetic cost when fatigued. Athletes exhibited a lower running energetic cost when wearing the low curvature plate in a non-fatigued state (P = 0.034; − 1.13 [− 1.92 to − 0.11] %), which persisted with better performance in the 3000-m trial (P = 0.017; − 0.42 [− 0.74 to − 0.09] %). However, in a fatigued state, non-significant differences were reported (P = 0.207). The low curvature plate seems to be more effective than the high curvature plate when running at low intensity in a fresh state as well as in a maximal high-intensity effort. However, non-significant differences between plate geometries were observed when fatigue was increased.

Competitive sport climbing progressed massively within the last quarter century. Development of technology enabling qualitative and quantitative analysis is required to withstand the challenges for athletes and trainers. This paper deals with the statistical study of a data set generated by the application of several image processing algorithms and neural networks on competition recordings. Therefore, calculated parameters are combined with random variables for the implementation of a linear mixed effect model. The resulting model enables the prediction of the end time of different athletes and the determination of its correlation with the input variables. Furthermore, analysis of velocity and path of the centre of gravity in different wall sections is done for all available speed climbing athletes. The observed data set consists of 297 runs in total divided into two subsets of 202 observations of 47 male and 95 of 25 female athletes. Among others, the statistical model was used for the validation of the measured parameters and the review and impact of proven techniques like the Tomoa skip in the start section. Likewise interesting is the high influence of the parameters, measured especially in the middle section of the wall, on the end time.

In gravity-powered sports, more mass at the same drag area results in a shorter finish time. Based on the body mass data and the finish times of the Skeleton and Luge competitions at the 2018 Winter Olympics, this study investigated the fairness of rules, by establishing trends between finish time and body mass or simulated system mass. A glide model served for the assessment of the sensitivity of mass, drag area and coefficient of friction, and for determining how much mass were required to tie with the next higher rank of the first four athletes of each competition. The rules of Skeleton and Luge competitions permit the use of ballast mass as a function of the athletes’ body mass, but the reference mass was up to 10 kg too low. When correlating the finish time with the body mass, all trends were significant (p ≤ 0.032; α = 0.05) which indicated that the finish times were mass dependent. Correlating the finish time with the simulated system mass reveals the same result except for the men’s Luge competition. The sensitivity analysis showed that 15% change of an input parameter resulted in about 1% change of the finish time. Despite the low sensitivity, the masses required to tie with the next highest rank ranged from 0.02 to 20 kg, with a median of 0.7 kg. The skeleton rules were improved in 2020 which now provide equal conditions across a wide range of body masses; however, the current Luge rules still disadvantage lighter athletes even when using the permitted ballast mass.