Real-Time Humidity Measurement during Sports Activity using Optical Fibre Sensing

An optical fibre sensor for monitoring relative humidity (RH) changes during exercise is demonstrated. The humidity sensor comprises a tip coating of poly (allylamine hydrochloride) (PAH)/silica nanoparticles (SiO2 NPs) deposited using the layer-by-layer technique. An uncoated fibre is employed to compensate for bending losses that are likely to occur during movement. A linear fit to the response of the sensing system to RH demonstrates a sensitivity of 3.02 mV/% (R2 = 0.96), hysteresis ± 1.17% RH when 11 bilayers of PAH/SiO2 NPs are coated on the tip of the fibre. The performance of two different textiles (100% cotton and 100% polyester) were tested in real-time relative humidity measurement for 10 healthy volunteers. The results demonstrate the moisture wicking properties of polyester in that the relative humidity dropped more rapidly after cessation of exercise compared to cotton. The approach has the potential to be used to monitor sports performance and by clothing developers for characterising different garment designs

Oral application of L-menthol in the heat: From pleasure to performance

When menthol is applied to the oral cavity it presents with a familiar refreshing sensation and cooling mint flavour. This may be deemed hedonic in some individuals, but may cause irritation in others. This variation in response is likely dependent upon trigeminal sensitivity toward cold stimuli, suggesting a need for a menthol solution that can be easily personalised. Menthol’s characteristics can also be enhanced by matching colour to qualitative outcomes; a factor which can easily be manipulated by practitioners working in athletic or occupational settings to potentially enhance intervention efficacy. This presentation will outline the efficacy of oral menthol application for improving time trial performance to date, either via swilling or via co-ingestion with other cooling strategies, with an emphasis upon how menthol can be applied in ecologically valid scenarios. Situations in which performance is not expected to be enhanced will also be discussed. An updated model by which menthol may prove hedonic, satiate thirst and affect ventilation will also be presented, with the potential performance implications of these findings discussed and modelled. Qualitative reflections from athletes that have implemented menthol mouth swilling in competition, training and maximal exercise will also be included

The development of a quick dry fabric for outdoors garments

Engineered clothing systems are one of the major textile research areas. These systems have a huge potential in providing protection and comfort to the wearer. Basically, multi-layered fabric technique is used, in which each layer contributes a substantial moisture removal function. The process of moisture removal is greatly affected by the surrounding conditions, such as pressure, temperature and humidity. If these quantities are much higher than the inner microclimate, the moisture removal process is affected, due to reduced hydrostatic pressure. However, the technology of heating in textile systems is widely available but not used as a way of improving and controlling moisture removal. The project main objective is to investigate the feasibility of using heating elements together with knitted spacer structures so as to maintain and transfer moisture by capillary effect in order to be used for moisture management textiles. To achieve this a mathematical model to study the moisture transfer process was created and simulated results based on knitted spacer fabric with a construction of 2 tucks and 2 ends was found to be significant. It showed that application of 4W heating using a carefully designed Thermoknit knitted elements which was integrated on the inner side of the spacer fabric successfully improved the moisture transfer by 30% per 11.5 X 11.5 cm sample size. This was further studied on the novel, constructed test rig with two mini-chambers that created controlled climatic conditions as experienced when a textile is situated between the inner microclimate and the outside environment. The same conditions and properties were used for the spacer fabric sample and found to coincide with numerical results. A prototype garment was created using the 2-tuck-2-end spacer fabric with integrated Thermoknit heater elements on the inner side of the garment

The Assessment of Practical Per-Cooling Targeting Peripheral Limbs During Exercise in Hot and Humid Environments

When excess body heat generation owing to the performance of exercise coincides with the heat dissipation limitations presented by hot and humid environments, the body’s ability to maintain thermal balance is compromised, and internal temperatures can rise to dangerous levels. Individuals who exercise in hot environments commonly look to acute cooling strategies to provide thermoregulatory assistance in order to avoid the health risks and performance decrements brought about by elevated thermal stress. Many cooling techniques aim to apply cold surfaces to large areas of skin on the torso, head, or neck to extract heat directly from core regions of the body. These locations, however, are often difficult to access without disrupting movement. In many exercise modalities including cycling, paddle sports, or wheelchair sports, however, peripheral regions such as the upper or lower limbs remain almost stationary, and may present a convenient location to apply cooling garments/equipment without disrupting required movements. The research studying the impact of practically applicable cooling techniques at these locations, however, is limited and inconclusive, prompting the present work. This document first outlines the quantifiable heat transfer principles that determine human thermal behaviour, and discusses the effects of thermal stress and acute cooling interventions. It then outlines practical considerations regarding the applications of cooling techniques, motivating the proposal of a novel technique that does not interfere with exercise performance by targeting the volar forearm skin of cyclists during exercise. The impacts of forearm cooling are then assessed experimentally during cycling ergometry exercise in a hot and humid environment. The cooling was observed to reduce the rate of core temperature rise by 0.43 ± 0.34°C/hr (p=0.002), while also eliciting significant reductions in heart rate drift and rating of thermal comfort. Computational modelling of the human thermal system was then employed to extend the experimental investigation and assess what impact the cooling may have during true cycling applications outside of the laboratory setting. Model outcomes suggest that the effects of the outdoor environment may reduce the effectiveness of the applied cooling slightly, but that the cooling will still be capable of providing quantifiable benefits. The impact of the cooling was also simulated across a range of ambient conditions, and the cooling was generally observed to be more impactful in hotter air temperatures and at higher ambient humidity levels

Textile Manufacturing Processes

Textile manufacturing is an important subject in textile programs and processing industries. The introduction of manmade and synthetic fibers, such as polyester, nylon, acrylic, cellulose, and Kevlar, among others, has greatly expanded the variety of textile products available today. In addition, new fiber development has brought about new machines for producing yarns, fabrics, and garments. Textile Manufacturing Processes is a collection of academic and research work in the field of textile manufacturing. Written by experts, chapters cover topics such as yarn manufacturing, fabric manufacturing, and garment and technical textiles. This book is useful for students, industry workers, and anyone interested in learning the fundamentals of textile manufacturing

A Scoping Review on Wearable Devices for Environmental Monitoring and Their Application for Health and Wellness

This scoping review is focused on wearable devices for environmental monitoring. First, the main pollutants are presented, followed by sensing technologies that are used for the parameters of interest. Selected examples of wearables and portables are divided into commercially available and research-level projects. While many commercial products are in fact portable, there is an increasing interest in using a completely wearable technology. This allows us to correlate the pollution level to other personal information (performed activity, position, and respiratory parameters) and thus to estimate personal exposure to given pollutants. The fact that there are no univocal indices to estimate outdoor or indoor air quality is also an open problem. Finally, applications of wearables for environmental monitoring are discussed. Combining environmental monitoring with other devices would permit better choices of where to perform sports activities, especially in highly polluted areas, and provide detailed information on the living conditions of individuals

Properties and Applications of Himalayan Nettle Fibre

The persistent demand for sustainable and eco – friendly fibres able to achieve high performance materials drew the attention to bast fibres, which, in this regard, represent an attractive resource. They are characterised by their fineness, flexibility, and excellent tensile properties due to the cellulose volume fraction. In particular, the fibre of the Himalayan giant nettle plant (Girardinia diversifolia), which grows in Africa and Asia, simultaneously provides social and environmental benefits as well as attractive physical properties, making it an interesting fibre for high performance sustainable textiles. This research provides an unprecedented investigation on giant Himalayan nettle fibres, currently processed and used in the handicraft, performed in parallel with common European nettle fibre (Urtica dioica) already used in the textile industry. The morphological, physical, and mechanical characterisation of G. diversifolia fibres provide encouraging results, indicating a substantial superiority (in terms of physical and mechanical properties) of Himalayan nettle fibres compared to the most common textile bast fibres. Himalayan nettle fibres displayed higher tensile strength, tensile modulus, and elongation at break with respect to European nettle fibres. Furthermore, the Himalayan nettle fibre is the longest bast fibre known so far. Its moisture content results indicate effective dielectric insulating capacity. The values of moisture regain, inferior to cotton, show that the fibre physical characteristics are not affect by humidity. Treatment with increasing concentrations of sodium hydroxide (NaOH) was carried out in order to induce changes in the molecular structure, from Cellulose I to Cellulose II, of both Himalayan and European nettle fibres, and to assess how this variation could influence their physical and mechanical characteristics. This research has identified as best result the fibre versatility: the ability to obtain, with alkaline treatment, characteristics of the fibre able to meet different purposes. To make the fibre attractive for the textile industry, Himalayan nettle fibre has to be competitive demonstrating that it can work in technical textiles. The field of outdoor sportswear, where a high level of comfort is required, has been chosen to demonstrate the performance of the Himalayan nettle fibre hypothesising a multilayer fabric made of three Himalayan nettle nonwovens treated at three different concentrations of NaOH. Based on its superior fibre length and mechanical strength, Himalayan giant nettle fibre could be a very promising material for advanced nonwovens where high – performance materials are required