Assessment of accelerometer-derived data in the context of seat height changes in cycling and the impact on running in triathlon

Triathlon has been an Olympic sport since the 2000 Sydney Olympics and has developed rapidly, leading to variations in race categories. Although running after cycling necessitates a postural change from a non-weight-bearing activity to a weight bearing one, no study has quantified the magnitude of trunk acceleration during cycling in different seat positions and the consequential effect on running. Therefore, this study was conducted to evaluate the effectiveness of a triaxial accelerometer to determine acceleration magnitudes of the trunk in a 20 km outdoor cycling event in two seat positions that were immediately followed by a 5 km overground run. Interpretation of data was evaluated based on cadence changes while triathletes cycled in an aerodynamic position in two seat positions. Running data was evaluated based on sinusoidal curves and foot strike peaks. The evaluation of accelerometer derived data within a characteristic overground setting suggests that cycling in an adjusted seat position significantly reduced trunk acceleration in both longitudinal and mediolateral directions with large effects ( p < 0.0001, d > 0.9). A significant and large effect was found in both longitudinal and anteroposterior trunk acceleration in post-cycle running between seat positions ( d > 0.9, p < 0.0001). In the longitudinal direction, a significant reduction in trunk acceleration occurred when running after the seat was adjusted with participants completing the 5 km run faster (21:55 ± 3:17 min compared to 22:05 ± 2:53 min). The results suggest that when the seat position is adjusted based on individual anthropometrics, overall trunk acceleration magnitude is reduced in both cycling and running. Accessible and practical sensor technology could be beneficial for postural considerations in triathlons.

FRI-1 Is an Anti-Cancer Isoquinolinequinone That Inhibits the Mitochondrial Bioenergetics and Blocks Metabolic Shifts by Redox Disruption in Breast Cancer Cells

Since breast cancer (BC) cells are dependent on mitochondrial bioenergetics for promoting proliferation, survival, and metastasis, mitochondria highlight as an important target for anticancer drug discovery. FRI-1, methyl 1, 3-dimethyl-5, 8-dioxo-5, 8-dihydro-4-isoquinolinecarboxylate, was previously described as a selective cytotoxic compound on cancer cell lines, however, details on the mechanism of action remain unknown. In this work, we describe that FRI-1 inhibits mitochondrial bioenergetics, producing apoptosis in MCF7 and MDA-MB-231 BC cell lines. FRI-1 decreases the maximal oxygen consumption rate (OCR), Δψm, NADH, and ATP levels, with a notable increase of mitochondrial reactive oxygen species (ROS) production, promoting AMPK activation with pro-survival effects. Moreover, FRI-1 inhibits the metabolic remodeling to glycolysis induced by oligomycin. In isolated tumoral mitochondria, FRI-1 increases Complex I and III-dependent OCR state 2, and this is sensitive to rotenone and antimycin A inhibitor additions, suggesting a redox cycling event. Remarkably, α-ketoglutarate and lipoic acid supplementation reversed and promoted, respectively, the FRI-1-induced apoptosis, suggesting that mitochondrial redox disruption affects 2-oxoglutarate dehydrogenase (OGDH) activity, and this is involved in their anticancer mechanism. Consistent with this, the combination of FRI-1 and CPI-613, a dual inhibitor of redox-sensible tricarboxylic acid (TCA) cycle enzymes PDH and OGDH, produced extensive BC cell death. Taken together, our results suggest that FRI-1 exhibits anticancer effects through inhibition of mitochondrial bioenergetics by redox disruption in BC cells.

Cycling in the Flattened City: Urban Assemblages and Digital Visual Research

As urban assemblage theory emphasizes a conceptualization of the city as movement, constituted through the processual interactions between different human and non-human actors. This approach has been recognized as potentially valuable for the study of active bodies in urban environments ( Rick and Bustad 2020 ). Moreover, this approach also encourages the development and implementation of innovative methodologies aimed at conveying the complexity of urban life ( McFarlane and Anderson 2011 ). This article contributes to this approach through the use of digital visual research methods while experiencing a monthly cycling event in Baltimore, Maryland. In particular, we discuss how GoPro cameras might be utilized within the study of the embodied experience of urban cycling, and how this experience demonstrates the assemblage of human, machine, and urban environment. Following Sumartojo and Pink (2017) , we describe how GoPro recordings of active urban embodiment work to provide more than second-hand representations of others’ experiences, and instead can serve to collect and analyze ‘traces’ of the assemblages of urban physical cultures.

Women, older age, faster cycling speed and increased wind speeds are independent risk factors for acute injury-related medical encounters during a 109 km mass community-based participation cycling event: a 3-year study in 102251 race starters—SAFER XII

BackgroundThere are limited data on acute injury-related medical encounters (injuries) in endurance cycling events.ObjectiveTo determine the risk factors for injuries during a mass community-based endurance cycling event.DesignRetrospective, cross-sectional study.SettingCape Town Cycle Tour (109 km), South Africa.Participants102 251 race starters.MethodsAll injuries for 3 years were recorded by race medical doctors and nurses. Injuries were grouped into main anatomical area of injury, and a Poisson regression model was used to determine the risk factors associated with injuries.ResultsThe four injury risk factors associated with all injuries during an endurance cycling event were sex (women vs men, p<0.0001), older age (p=0.0005), faster cycling speed (p<0.0001) and higher average individualised Wind Speed (aiWindSpeed, p<0.0001). The only risk factor for serious/life-threatening injuries was women (p=0.0413). For specific main anatomical areas: head/neck (women), upper limb (women, older age, faster cyclists), trunk (women, higher aiWindSpeed), and lower limb (higher aiWindSpeed).ConclusionWomen, older age, faster cycling speed and higher aiWindSpeed were all risk factors for acute injuries during a mass community-based endurance cycling event. These risk factors should help inform race organisers and medical teams on race day to ensure the best medical care is given, and effective acute injury prevention programmes are disseminated.

The Tweed Run meets Harris Tweed: Stories of a fashionable cycling experience

This article explores the relationship between the cloth Harris Tweed and the cycling event, the Tweed Run. It focuses on extrapolating stories as lived and told of those participating in the event, to examine how material objects can lend agency to a fashionable cycling experience. Narrative inquiry methodology is used to explore how a subject emotionally connects with their personal possessions as revealed through storytelling. The aim is to create a new sense of meaning and significance within the research topic, rather than focusing on establishing a grand narrative. It brings specific understandings to how objects can be related to and used by individuals to become symbolic and aesthetic ‘thirds’. This study posits that it is the participatory collective nature and transformative space of events such as the Tweed Run that provide an opportunity for individuals to interact with their material objects, in a manner that supports their transformation to symbolic or aesthetic thirds and initiates satisfactory (life) stories that can advance living action.