This study investigated the effectiveness of head cooling on cognitive performance after 30 min and 60 min of running in the heat. Ten moderately-trained, non-heat-acclimated, male endurance athletes (mean age: 22 ± 6.6 y; height: 1.78 ± 0.10 m; body-mass: 75.7 ± 15.6 kg; VO2peak: 51.6 ± 4.31 mL-1>kg-1>min) volunteered for this study. Participants performed two experimental trials: head cooling versus no-cooling (within-subjects factor with trial order randomized). For each trial, participants wore a head-cooling cap for 15 min with the cap either cooled to 0°C (HC) or not cooled (22°C; CON). Participants then completed 2 × 30 min running efforts on a treadmill at 70% VO2peak in hot conditions (35°C, 70% relative humidity), with a 10 min rest between efforts. Working memory was assessed using an operation span (OSPAN) task immediately prior to the 15 min cooling/no-cooling period (22°C, 35% RH) and again after 30 min and 60 min of running in the heat. Numerous physiological variables, including gastrointestinal core temperature (Tc) were assessed over the protocol. Scores for OSPAN were similar between trials, with no interaction effect or main effects for time and trial found (p = 0.58, p = 0.67, p = 0.54, respectively). Forehead temperature following precooling was lower in HC (32.4 ± 1.6°C) compared with CON (34.5 ± 1.1°C) (p = 0.01), however, no differences were seen in Tc, skin temperature, heart rate and ratings of perceived exertion between HC and CON trials at any time point assessed (p > 0.05). In conclusion, despite HC reducing forehead temperature prior to exercise, it did not significantly improve cognitive performance during (half-time break) or after subsequent exercise in hot environmental conditions, compared to a no cooling control.
International competition inevitably presents logistical challenges for athletes. Events such as the Tokyo 2020 Olympic Games require further consideration given historical climate data suggest athletes will experience significant heat stress. Given the expected climate, athletes face major challenges to health and performance. With this in mind, heat alleviation strategies should be a fundamental consideration. This review provides a focused perspective of the relevant literature describing how practitioners can structure male and female athlete preparations for performance in hot, humid conditions. Whilst scientific literature commonly describes experimental work, with a primary focus on maximizing magnitudes of adaptive responses, this may sacrifice ecological validity, particularly for athletes whom must balance logistical considerations aligned with integrating environmental preparation around training, tapering and travel plans. Additionally, opportunities for sophisticated interventions may not be possible in the constrained environment of the athlete village or event arenas. This review therefore takes knowledge gained from robust experimental work, interprets it and provides direction on how practitioners/coaches can optimize their athletes' heat alleviation strategies. This review identifies two distinct heat alleviation themes that should be considered to form an individualized strategy for the athlete to enhance thermoregulatory/performance physiology. First, chronic heat alleviation techniques are outlined, these describe interventions such as heat acclimation, which are implemented pre, during and post-training to prepare for the increased heat stress. Second, acute heat alleviation techniques that are implemented immediately prior to, and sometimes during the event are discussed. Abbreviations: CWI: Cold water immersion; HA: Heat acclimation; HR: Heart rate; HSP: Heat shock protein; HWI: Hot water immersion; LTHA: Long-term heat acclimation; MTHA: Medium-term heat acclimation; ODHA: Once-daily heat acclimation; RH: Relative humidity; RPE: Rating of perceived exertion; STHA: Short-term heat acclimation; TCORE: Core temperature; TDHA: Twice-daily heat acclimation; TS: Thermal sensation; TSKIN: Skin temperature; V̇O2max: Maximal oxygen uptake; WGBT: Wet bulb globe temperature.
This study investigated the muscle activity and force variability in response to perturbation of assistive force during isometric elbow flexion. Sixteen healthy right-handed young men (age: 22.0 ± 1.1 years; height: 171.9 ± 4.8 cm; weight 68.4 ± 11.2 kg) were recruited and the muscle activity of biceps brachii and triceps brachii were assessed using surface electromyography. Workload force and assistive force applied on isometric elbow flexion significantly affected the changes in both biceps and triceps muscle activities. A higher assistive force was shown to result in reduced biceps muscle activity compared to the unassisted period. In contrast, the efficiency of the assistive force acting on the biceps decreased as the assistive force increased. In general, the force variability of the biceps muscle remained approximately the same at lower workload force conditions than that at higher workload force conditions. In conclusion, higher assistive force may not yield a higher performance efficiency in human-assistive force interaction.
Introduction: Athletes train physically to reach beyond their potential maximum aerobic threshold. Whey protein supplements (WPS) are often used in conjunction with physiotherapy and psychotherapy to regain better vital sign and physical performances. This review aimed to explore the clinical evidence on the efficacy and safety of WPS in sports performance and recovery among athletes. Methodology: A comprehensive literature search was performed to identify relevant randomized control trials (RCTs) that investigated the efficacy and safety of WPS on the vital sign and physical performance among athletes. The Cochrane Risk of Bias (ROB) Assessment tools were used to assess the quality of the studies. Meta-analysis was conducted using the frequentist model with STATA version 14.2®. Results: A total of 333,257 research articles were identified out of which 20 RCTs were included for qualitative synthesis and network meta-analysis with 351 participants. Among the studies, 7 had low ROB and 3 RCTs had high ROB. Of these 20 trials, 16 trials were randomized clinical trials which compared whey protein supplements (WPS) with various comparators i.e., L-alanine, bovine colostrum, carbohydrate, casein, leucine, maltodextrin, rice, protein + caffeine were compared with placebo. Analysis from the pairwise meta-analysis revealed that for respiratory exchange ratio (RER) WPS was found to be significantly improving compared to maltodextrin (WMD = 0.012; 95%CI = 0.001, 0.023). Similarity to RPE (Rate Perceived Exertion), slight difference between WPS and the comparators, however, when the estimation was favorable to the comparators, there was moderate-high heterogeneity. For VO2max, high heterogeneity appeared when WPS compared to maltodextrin with the I2 = 97.8% (WMD = 4.064; 95% CI = -4.230, 12.359), meanwhile bovine colostrum (WMD = -2.658; 95%CI = -6.180, 0.865) only comparator that was better than WPS. According to the estimated effect of the supplements on physical performance outcome results, maximum power (8 studies, 185 athletes), highest ranked was bovine colostrum (SUCRA = 70.7%) and the lowest ranked was placebo (SUCRA = 17.9%), yet all insignificant. Then again, on average power (nine studies, 187 athletes), WPS was the highest ranked (SUCRA = 75.4 %) about -112.00 watt (-187.91, -36.08) and most of the estimations were significant. Body mass was reported in 10 studies (171 athletes), carbohydrate may be at the highest ranked (SUCRA = 66.9%) but it is insignificant. Thought the second highest ranked was WPS (SUCRA = 64.7%) and it is significant (WMD = -6.89 kg; CI = -8.24, -5.54). Conclusion: The findings of this review support the efficacy and safety of WPS as an ergogenic aid on athletes' sports performance and recovery. The overall quality of clinical evidence was found to be valid and reliable from the comprehensive search strategy and ROB assessment.
This study aimed to examine adolescents' acute cardiorespiratory and perceptual responses during high-intensity interval exercise (HIIE) and enjoyment responses following HIIE and work-matched continuous moderate intensity exercise (CMIE). Fifty-four 12- to 15-year olds (27 boys) completed 8 × 1-min cycling at 90% peak power with 75-s recovery (HIIE) and at 90% of the gas exchange threshold (CMIE). Absolute oxygen uptake ([Formula: see text]), percentage of maximal [Formula: see text] (%[Formula: see text]), heart rate (HR), percentage of maximal HR (%HRmax) and ratings of perceived exertion (RPE) were collected during HIIE. Enjoyment was measured using the physical activity enjoyment scale (PACES) following HIIE and CMIE. Boys elicited higher absolute [Formula: see text] during HIIE work (p 1.22) and recovery (p 0.51) intervals but lower %[Formula: see text] during HIIE recovery intervals compared to girls (p 0.67). No sex differences in HR and %HRmaxwere evident during HIIE and 48 participants attained ≥90% HRmax. Boys produced higher RPE at intervals 6 (p = .004, ES = 1.00) and 8 (p = .003, ES = 1.00) during HIIE. PACES was higher after HIIE compared with CMIE (p = .003, ES = 0.58). Items from PACES "I got something out of it", "It's very exciting" and "It gives me a strong feeling of success" were higher after HIIE (all p 0.32). The items "I feel bored" and "It's not at all interesting" were higher after CMIE (all p 0.46). HIIE elicits a maximal cardiorespiratory response in most adolescents. Greater enjoyment after HIIE was due to elevated feelings of reward, excitement and success and may serve as a strategy to promote health in youth.
Heat stroke is a medical emergency which may lead to mortality unless diagnosed early and treated effectively. Heat stroke may manifest rapidly, hence making it difficult to differentiate it from other clinical causes in a collapsed victim.(1) We are presenting a case report of twelve patients who were admitted to our emergency department from a music festival held on 13-15th of March 2014. They developed complications arising from a combination of severe adverse weather condition, prolonged outdoor physical exertion due to long hours of dancing and drug-use, resulting in heat stroke. Three of them died while the remaining patients survived. Their condition was initially misdiagnosed as a classical illicit drug overdose. This was based on the history of drug ingestion by some of the patients who attended the music festival on that day. The information in this case report aims, to create awareness amongst members of the medical team on duty in outdoor events, pre hospital responders and ED physicians when treating and managing similar cases in the future. In addition it is intended to warn the organizers of such events to take adequate precautions to avoid such tragedies in the future.
The aim of the study was to examine and analyze the epidemiology and outcome of treatment for paediatric acquired subglottic stenosis treated with endoscopic bougie dilatation and topical mitomycin C. There were 15 patients identified from 2008 until 2013. All of them had acquired subglottic stenosis due to history of intubation. Majority of the patients had grade III stenosis, with the total of seven. Three patients had grade IV; three were grade II and two were grade I. All of the patients with severe stenosis (grade III and IV) needed tracheostomy while only one in mild stenosis group (grade I and II) required it for prolonged ventilation rather than obstruction due to subglottic stenosis. All of them underwent direct laryngoscopy under general anesthesia followed by endoscopic dilatation with bougie and topical mitomycin C 0.4 mg/ml for 5 min. Aim of success in our study was decannulation of tracheostomy or absence of symptoms at exertion. We achieved 6 (60 %) successful decannulation out of 10 patients with tracheostomy (excluded the patient with tracheostomy in grade I stenosis due to prolonged ventilation). As for those without tracheostomy, 3 (75 %) out of 4 patients were asymptomatic even at exertion. Average number of dilatation was 3.1 times, with mean duration of 28 min. No complications were reported in our series. One patient with grade I stenosis passed away due to severe pneumonia unrelated to the stenosis or dilatation, and she did not have any dilatation before she passed away. Multiple related risk factors were identified such as intubation, prematurity, movement of endotracheal tube, respiratory infection, traumatic intubation and gastroesophageal reflux disease. Experience of open surgical method was very limited in our centre in Sabah in East Malaysia. Endoscopic technique plays an important role in treatment of subglottic stenosis with adjunct like mitomycin C possibly booster the successful rate.
Domestic maid violence is an assault and coercive behaviour, which mainly includes physical, psychological and at times sexual too, by employer or household members of employer against a person hired as a domestic help. Maid abuse is well known but poorly documented in scientific literature. This is an important global issue. In this article, two illustrated cases of maid abuse are discussed. Their employers allegedly subjected both the victims to physical and psychological trauma. The physical examination of the victims showed poor state of clothing, nutrition, and presence of injuries of different duration. The bruises were irregular to patterned, and were inflicted by beating. Both cases had eczematous contact dermatitis over palms and soles, paronechia, and sub-ungal fungal infection due to unprotected working in wet conditions. In both cases, external ears were deformed like cauliflowers due to repeated trauma. All cases had multiple injuries of varying duration. In this paper, medico-legal and social issues related to maid abuse are also discussed in detail. A possible solution to minimise maid abuse is also suggested. This paper highlights and document maid abuse.
Indo-Asians in the UK are at an increased risk of coronary artery disease (CAD); this may be a reflection of their cardiovascular risk factor profile as well as of a more sedentary lifestyle. We hypothesised that Indo-Asians in Malaysia and the UK may exhibit a similar cardiovascular risk factor and physical activity profile, which would be more adverse compared with caucasians. We studied 70 consecutive Indo-Asian patients admitted to hospitals in Kuala Lumpur, Malaysia (n=42; 35 males; mean age 60.6 years, SD 11.8); and Birmingham, England (n=28; 20 males; mean age 60.8 years, SD 12.9). Both groups of Indo-Asian patients were compared with 20 caucasian patients (13 males; mean age 62.7 years, SD 9.4) admitted with myocardial infarction from Birmingham. There was a higher prevalence of diabetes among Indo-Asians in both countries than among caucasians (p=0.0225). By contrast, caucasians had a higher prevalence of hypercholesterolaemia (p=0.0113), peripheral vascular disease (p=0.0008), regular alcohol consumption (p<0.0001) and family history of CAD (p=0.0041). There were no significant differences in mean age, body mass index or blood pressures. There was a significantly lower leisure activity score (p=0.001) and total physical activity score (p=0.003) among Indo-Asians in both countries than among caucasians. This survey has demonstrated differences in cardiovascular risk factors among Indo-Asian and caucasian patients. The high prevalence of diabetes, as well as the lower physical activity and sedentary lifestyles among Indo-Asians, in both Malaysia and the UK, may in part contribute to the high incidence of CAD in this ethnic group.
Clinical studies were carried out on mild Indian sickle cell anaemia in Malaysia, and genetic and fertility studies were carried out on 101 families with and without sickle-cell haemoglobin (Hb S). The Indian sickle cell anaemia patients reached adulthood, and pregnancies and deliveries were uneventful without blood transfusion. There was no foetal wastage and the number of children produced was not significantly different from that in families without Hb S. 28 Indian patients hospitalized with Plasmodium falciparum malaria infection were also examined for their beta S genotype. P. falciparum malaria infection occurred much more frequently in individuals without Hb S than in Hb S carriers.
Box-traps for capturing wild cats are widely used by researchers since it is one of the most effective methods for trapping these species. Although they are extensively utilised, the effects on the physiology of trapped felids remain unclear. Researchers frequently make judgements regarding the safety of such capture devices by examination of external injuries but often fail to take into consideration other physiological parameters. To assess the effects of capture events on selected serum biochemistry values of free-ranging Bornean leopard cats (Prionailurus bengalensis borneoensis) six free-ranging leopard cats (four males, two females) were trapped by using box-traps in Sabah, Malaysian Borneo. Blood was collected by jugular venipucture after chemical immobilization with a mixture of tiletamine and zolazepam. Blood was analysed for 17 serum biochemistry parameters. The most consistent and significantly higher value found in both sexes was aspartate aminotransferase (AST), followed by high mean value of alanine aminotransferase (ALT). Both mean values exceeded the upper limit of the reference range for captive leopard cats. These results demonstrate that captured leopard cats by box-traps undergo physical exertion and consequently some type of muscle injury/damage. Researchers and wildlife managers should be aware of the physiological response of trapped felids when using box-traps. Devices that facilitate the prompt removal of leopard cats from the traps would be useful for researchers to avoid further damage while live trapping this species.
Prevalence and predictors associated with musculoskeletal disorders (MSDs) vary considerably between countries. It is plausible that socio-cultural contexts may contribute to these differences. We conducted a cross-sectional survey with 1184 Malaysian and Australian office workers with the aim to examine predictors associated with MSD discomfort. The 6-month period prevalence of self-reported MSD discomfort for Malaysian office workers was 92.8% and 71.2% among Australian workers. In Malaysia, a model regressing level of musculoskeletal discomfort against possible risk factors was significant overall (F [6, 370] = 17.35; p