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Neurostimulation, doping, and the spirit of sport
Get PDFThere is increasing interest in using neuro-stimulation devices to achieve an ergogenic effect in elite athletes. Although the World Anti-Doping Authority (WADA) does not currently prohibit neuro-stimulation techniques, a number of researchers have called on WADA to consider its position on this issue. Focusing on trans-cranial direct current stimulation (tDCS) as a case study of an imminent so-called ‘neuro-doping’ intervention, we argue that the emerging evidence suggests that tDCS may meet WADA’s own criteria (pertaining to safety, performance-enhancing effect, and incompatibility with the ‘spirit of sport’) for a method’s inclusion on its list of prohibited substances and methods. We begin by surveying WADA’s general approach to doping, and highlight important limitations to the current evidence base regarding the performance-enhancing effect of pharmacological doping substances. We then review the current evidence base for the safety and efficacy of tDCS, and argue that despite significant shortcomings, it may be sufficient for WADA to consider prohibiting tDCS, in light of the comparable flaws in the evidence base for pharmacological doping substances. In the second half of the paper, we argue that the question of whether WADA ought to ban tDCS turns significantly on the question of whether it is compatible with the ‘spirit of sport’ criterion. We critique some of the previously published positions on this, and advocate our own sport-specific and application-specific approach. Despite these arguments, we finally conclude by suggesting that tDCS ought to be monitored rather than prohibited due to compelling non-ideal considerations
Identifying support mechanisms to overcome barriers to food safety scheme certification in the food and drink manufacturing industry in Wales, UK.
Get PDFObtaining food safety certification is essential for food manufacturers. Potential barriers to
obtaining certification are complex, interrelated and broadly relate to, ‘knowledge and skills’,
‘time, cost and resources’, and ‘communication and access to information’. This study aimed to
explore requirements for support to enable food manufacturers in Wales to overcome identified
barriers. Food manufacturers (n=37) participated in group discussions (n=2) and completed
online-questionnaires (n=29). Support mechanisms, perceived necessary to obtain food safety
certification included; funding for training and audit-fees, support for implementing food safety
scheme documentation, on-site support through mentoring/coaching and pre-audits. Findings
identify the need for a food safety scheme certification support package pathway incorporating
online, off-site, on-site and financial support to assist food and drink manufacturers obtain
third-party food safety certification. Such assistance would support three critical areas. Findings
may inform development of support mechanisms to increase uptake of food safety certification
and accelerate food-sector growth
Event Related Potential Evidence of Enhanced Visual Processing in Auditory Associated Cortex in Adults with Hearing Loss
Get PDFObjective: The present study investigated the characteristics of visual processing in the auditory-associated cortex in adults with hearing loss using event-related potentials. Methods: Ten subjects with bilateral postlingual hearing loss were recruited. Ten age- and sex-matched normal-hearing subjects were included as controls. Visual (“sound” and “non-sound” photos)-evoked potentials were performed. The P170 response in the occipital area as well as N1 and N2 responses in FC3 and FC4 were analyzed. Results: Adults with hearing loss had higher P170 amplitudes, significantly higher N2 amplitudes, and shorter N2 latency in response to “sound” and “non-sound” photo stimuli at both FC3 and FC4, with the exception of the N2 amplitude which responded to “sound” photo stimuli at FC3. Further topographic mapping analysis revealed that patients had a large difference in response to “sound” and “non-sound” photos in the right frontotemporal area, starting from approximately 200 to 400 ms. Localization of source showed the difference to be located in the middle frontal gyrus region (BA10) at around 266 ms. Conclusions: The significantly stronger responses to visual stimuli indicate enhanced visual processing in the auditory-associated cortex in adults with hearing loss, which may be attributed to cortical visual reorganization involving the right frontotemporal cortex
Neuromechanical response of the upper body to unexpected perturbations during gait initiation in young and older adults
Get PDFBackground:
Control of upper body motion deteriorates with ageing leading to impaired ability to preserve balance during gait, but little is known on the contribution of the upper body to preserve balance in response to unexpected perturbations during locomotor transitions, such as gait initiation.
Aim:
To investigate differences between young and older adults in the ability to modify the trunk kinematics and muscle activity following unexpected waist lateral perturbations during gait initiation.
Methods:
Ten young (25 ± 2 years) and ten older adults (73 ± 5 years) initiated locomotion from stance while a lateral pull was randomly applied to the pelvis. Two force plates were used to define the feet centre-of-pressure displacement. Angular displacement of the trunk in the frontal plane was obtained through motion analysis. Surface electromyography of cervical and thoracic erector spinae muscles was recorded bilaterally.
Results:
A lower trunk lateral bending towards the stance leg side in the preparatory phase of gait initiation was observed in older participants following perturbation. Right thoracic muscle activity was increased in response to the perturbation during the initial phase of gait initiation in young (+ 68%) but not in older participants (+ 7%).
Conclusions:
The age-related reduction in trunk movement could indicate a more rigid behaviour of the upper body employed by older compared to young individuals in response to unexpected perturbations preceding the initiation of stepping. Older adults’ delayed activation of thoracic muscles could suggest impaired reactive mechanisms that may potentially lead to a fall in the early stages of the gait initiation
The influence of biological maturity and competitive level on isometric force-time curve variables and vaulting performance in young female gymnasts
Get PDFThis cross-sectional study investigated isometric force-time curve variables and vaulting performance in young female gymnasts of varying maturity and competitive levels. One hundred twenty gymnasts aged 5–14 years were subdivided into maturity groupings and also according to their competitive level. Subjects performed isometric midthigh pulls (IMTP) before completing straight jump vaults that were recorded using two-dimensional video. All significance values were accepted at p < 0.05. Absolute peak force (PF abs) and force at various time epochs were significantly greater in more mature gymnasts, although no significant differences were observed in relative peak force (PF rel). When grouped by competitive level, elite gymnasts produced a significantly greater absolute rate of force development (RFD abs) at 0–150, 0–200, and 0–250 ms as well as relative RFD (RFD rel) at 0–200 and 0–250 ms than recreational gymnasts. Based upon regression analyses, force at 50 ms during the IMTP test explained 15% of vertical takeoff velocity during vaulting. Biological maturation seems to impact isometric force-time curve characteristics in young female gymnasts, and higher-level gymnasts produce greater RFD than those competing at a lower level. Vaulting vertical takeoff velocity seems to be largely independent of isometric force-time characteristics with only a small amount of variance explained by force at 50 ms
Preface: sustainable operations in manufacturing enterprise
Get PDFIt is indeed a real pleasure to announce the publication of this special issue, Sustainable Operations in Manufacturing Enterprise (SOME), for Annals of Operations Research. Overall, many papers were received for this special issue, and based on reviewer reports the best papers are included in this issue. This special issue is focused primarily on the three sustainable aspects, 3Ps of sustainability: profit, planet, and people. The accepted papers focus on sustainability, circular economy, mutli-criteria decision making (MCDM), optimization modelling using mixed integer linear/non-linear program (MLP/MINLP), and data envelopment analysis (DEA) having some applications to industry and society were considered
From secondary school to university: associations between sport participation and total and domain-specific sedentary behaviours in Spanish students
Get PDFEffective ways to reduce sedentary behaviour in adolescents are needed to mitigate the risk of chronic disease and poor mental health. Organised sport participation is the most practiced physical activity during adolescence. However, the influence sport participation has on sedentary behaviours remains unclear. This study investigated the associations between sport participation, total and domain-specific sedentary behaviour and physical activity during the transition from secondary school to university. A 3-year longitudinal survey followed Spanish secondary school students (n = 113) to their first year of university. Generalized linear models, adjusted by gender and year, assessed the relationships between sport participation, total and domain-specific sedentary behaviour and physical activity. Compared with non-sport participants, teenagers who played individual sports from baseline during secondary school spent significantly less total time sitting (− 110.5 min/day at weekends), watching television (− 18.7 min/day at weekends) or using the computer for leisure (− 37.4 min/day weekdays). Those who played team sports from baseline at secondary school spent less time sitting (− 126.4 min/day at weekends) or socialising (− 37 min/day at weekends).
Conclusion: From secondary school to university, sport participation–based interventions might be an effective strategy to reduce sitting time spent on some domain-specific behaviours. Promoting sports could reduce the rise of sedentary behaviour during adolescence, a stage where sedentary behaviour evolves
Pragmatic evaluation of a coproduced physical activity referral scheme: a UK quasi-experimental study
Get PDFObjectives UK exercise referral schemes (ERSs) have been criticised for focusing too much on exercise prescription and not enough on sustainable physical activity (PA) behaviour change. Previously, a theoretically grounded intervention (coproduced PA referral scheme, Co-PARS) was coproduced to support long-term PA behaviour change in individuals with health conditions. The purpose of this study was to investigate the effectiveness of Co-PARS compared with a usual care ERS and no treatment for increasing cardiorespiratory fitness.
Design A three-arm quasi-experimental trial.
Setting Two leisure centres providing (1) Co-PARS, (2) usual exercise referral care and one no-treatment control.
Participants 68 adults with lifestyle-related health conditions (eg, cardiovascular, diabetes, depression) were recruited to co-PARS, usual care or no treatment.
Intervention 16-weeks of PA behaviour change support delivered at 4, 8, 12 and 18 weeks, in addition to the usual care 12-week leisure centre access.
Outcome measures Cardiorespiratory fitness, vascular health, PA and mental well-being were measured at baseline, 12 weeks and 6 months (PA and mental well-being only). Fitness centre engagement (co-PARS and usual care) and behaviour change consultation attendance (co-PARS) were assessed. Following an intention-to-treat approach, repeated-measures linear mixed models were used to explore intervention effects.
Results Significant improvements in cardiorespiratory fitness (p=0.002) and vascular health (p=0.002) were found in co-PARS compared with usual care and no-treatment at 12 weeks. No significant changes in PA or well-being at 12 weeks or 6 months were noted. Intervention engagement was higher in co-PARS than usual care, though this was not statistically significant.
Conclusion A coproduced PA behaviour change intervention led to promising improvements in cardiorespiratory and vascular health at 12 weeks, despite no effect for PA levels at 12 weeks or 6 months
Stimulus-specific functional remodeling of the left ventricle in endurance and resistance-trained men
Get PDFLeft ventricular (LV) structural remodeling following athletic training has been evidenced through training-specific changes in wall thickness and geometry. Whether the LV response to changes in hemodynamic load also adapts in a training-specific manner is unknown. Using echocardiography, we examined LV responses of endurance-trained (n = 15), resistance-trained (n = 14), and nonathletic men (n = 13) to 1) 20, 40, and 60% one repetition-maximum (1RM), leg-press exercise and 2) intravascular Gelofusine infusion (7 mL/kg) with passive leg raise. While resting heart rate was lower in endurance-trained participants versus controls (P = 0.001), blood pressure was similar between groups. Endurance-trained individuals had lower wall thickness but greater LV mass relative to body surface area versus controls, with no difference between resistance-trained individuals and controls. Leg press evoked a similar increase in blood pressure; however, resistance-trained participants preserved stroke volume (SV; −3 ± 8%) versus controls at 60% 1RM (−15 ± 7%, P = 0.001). While the maintenance of SV was related to the change in longitudinal strain across all groups (R = 0.537; P = 0.007), time-to-peak strain was maintained in resistance-trained but delayed in endurance-trained individuals (1 vs. 12% delay; P = 0.021). Volume infusion caused a similar increase in end-diastolic volume (EDV) and SV across groups, but leg raise further increased EDV only in endurance-trained individuals (5 ± 5 to 8 ± 5%; P = 0.018). Correlation analysis revealed a relationship between SV and longitudinal strain following infusion and leg raise (R = 0.334, P = 0.054); however, we observed no between-group differences in longitudinal myocardial mechanics. In conclusion, resistance-trained individuals better maintained SV during pressure loading, whereas endurance-trained individuals demonstrated greater EDV reserve during volume loading. These data provide novel evidence of training-specific LV functional remodeling.
NEW & NOTEWORTHY Training-specific functional remodeling of the LV in response to different loading conditions has been recently suggested, but not experimentally tested in the same group of individuals. Our data provide novel evidence of a dichotomous, training-specific LV adaptive response to hemodynamic pressure or volume loading
Back to Basics: understanding Charcot neuroarthropathy
No full textActive’ Charcot neuroarthropathy (CN) is characterised by non-infectious inflammation in the presence of peripheral neuropathy (van Netten et al, 2019). The area of the foot most commonly affected is the mid-foot and this is associated with classic ‘rocker-bottom foot’ deformity (Botek et al, 2010; Mumoli et al, 2012; Dissanayake et al, 2012). While this condition is frequently associated with deformity, this may be prevented if caught early. Without timely recognition and offloading of the affected limb, progressive bone and joint destruction may, however, lead to significant deformity, ulceration, amputation and a vastly reduced quality of life (Caputo et al, 1998; Cates et al, 2019)