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1.
Ergonomics ; 63(10): 1329-1335, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32588761

RESUMO

This study examined movement economy under load with 1000 g minimalist (MIN) vs. 1600 g traditional (TRD) style boots. Fourteen trained, male participants completed a VO2peak test (46.6 ± 7.3 ml/kg/min) while wearing a 16 kg external load. Treadmill speeds for the running economy (RE) trials were determined by the slowest pace in which participants completed a full stage with a running gait pattern during the VO2peak test. Walking economy (WE) pace was 1.6 km/h slower than RE pace. During the second session, participants completed 5-min exercise bouts at WE and RE pace under load wearing MIN and TRD. There were no differences for any measured variables during WE trials. In contrast, RE (MIN = 2.95 ± 0.28 vs. TRD = 3.04 ± 0.30 L/min; p = .003: Cohen's d = 0.32), respiratory exchange ratio (p < .001), and perceptual measures (p < .05) were all improved while wearing MIN. Practitioner summary: In trained men, 1000 g/pair minimalist style boots (MIN) resulted in improvements of approximately 3% and 5% for running economy and respiratory exchange ratio versus 1600 g/pair traditional boots while wearing a 16 kg kit. Perceptual responses, including comfort, also favoured MIN. These effects were not found at walking pace. Abbreviations: MIN: minimalist style boots; TRD: traditional style boots; RE: running economy; WE: walking economy; ES: effect size; RER: respiratory exchange ratio; HR: heart rate.


Assuntos
Metabolismo Energético/fisiologia , Desenho de Equipamento , Consumo de Oxigênio/fisiologia , Corrida/fisiologia , Sapatos , Caminhada/fisiologia , Adulto , Teste de Esforço , Humanos , Masculino , Militares , Adulto Jovem
2.
Biol Sport ; 32(3): 249-54, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26424929

RESUMO

Sweat production is crucial for thermoregulation. However, sweating can be problematic for individuals with spinal cord injuries (SCI), as they display a blunting of sudomotor and vasomotor responses below the level of the injury. Sweat gland density and eccrine gland metabolism in SCI are not well understood. Consequently, this study examined sweat lactate (S-LA) (reflective of sweat gland metabolism), active sweat gland density (SGD), and sweat output per gland (S/G) in 7 SCI athletes and 8 able-bodied (AB) controls matched for arm ergometry VO2peak. A sweat collection device was positioned on the upper scapular and medial calf of each subject just prior to the beginning of the trial, with iodine sweat gland density patches positioned on the upper scapular and medial calf. Participants were tested on a ramp protocol (7 min per stage, 20 W increase per stage) in a common exercise environment (21±1°C, 45-65% relative humidity). An independent t-test revealed lower (p<0.05) SGD (upper scapular) for SCI (22.3 ±14.8 glands · cm(-2)) vs. AB. (41.0 ± 8.1 glands · cm(-2)). However, there was no significant difference for S/G between groups. S-LA was significantly greater (p<0.05) during the second exercise stage for SCI (11.5±10.9 mmol · l(-1)) vs. AB (26.8±11.07 mmol · l(-1)). These findings suggest that SCI athletes had less active sweat glands compared to the AB group, but the sweat response was similar (SLA, S/G) between AB and SCI athletes. The results suggest similar interglandular metabolic activity irrespective of overall sweat rate.

3.
Br J Psychiatry ; 204(3): 214-21, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24357575

RESUMO

BACKGROUND: Children in care often have poor outcomes. There is a lack of evaluative research into intervention options. AIMS: To examine the efficacy of Multidimensional Treatment Foster Care for Adolescents (MTFC-A) compared with usual care for young people at risk in foster care in England. METHOD: A two-arm single (assessor) blinded randomised controlled trial (RCT) embedded within an observational quasi-experimental case-control study involving 219 young people aged 11-16 years (trial registration: ISRCTN 68038570). The primary outcome was the Child Global Assessment Scale (CGAS). Secondary outcomes were ratings of educational attendance, achievement and rate of offending. RESULTS: The MTFC-A group showed a non-significant improvement in CGAS outcome in both the randomised cohort (n = 34, adjusted mean difference 1.3, 95% CI -7.1 to 9.7, P = 0.75) and in the trimmed observational cohort (n = 185, adjusted mean difference 0.95, 95% CI -2.38 to 4.29, P = 0.57). No significant effects were seen in secondary outcomes. There was a possible differential effect of the intervention according to antisocial behaviour. CONCLUSIONS: There was no evidence that the use of MTFC-A resulted in better outcomes than usual care. The intervention may be more beneficial for young people with antisocial behaviour but less beneficial than usual treatment for those without.


Assuntos
Comportamento do Adolescente/psicologia , Escolaridade , Cuidados no Lar de Adoção/psicologia , Delinquência Juvenil , Saúde Mental , Adolescente , Criança , Inglaterra , Feminino , Humanos , Masculino , Método Simples-Cego , Resultado do Tratamento
4.
Eur J Appl Physiol ; 113(3): 721-7, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22926324

RESUMO

This study examined effects of caffeine on session ratings of perceived exertion (RPE) following 30 min constant-load cycling. Individuals (n = 15) of varying aerobic fitness completed a [Formula: see text] max trial and two 30 min cycling bouts (double-blind, counterbalanced) following ingestion of 6 mL/kg of caffeine or matched placebo. RPE overall, legs and breathing were estimated every 5 min and session RPE was estimated 30 min post-exercise using the OMNI pictorial scale. Session RPE for caffeine and placebo trails were compared using paired t test. Between-trial comparisons of HR, RPE overall, RPE legs and RPE breathing were analyzed using an independent 2 (trial) × 6 (time point) repeated measures analysis of variance (ANOVA) for each dependent variable. Caffeine resulted in a significantly lower session RPE (p < 0.05) for caffeine (6.1 ± 2.2) versus placebo (6.8 ± 2.1). Acute perceptual responses were significantly lower for caffeine for RPE overall (15, 20, 25, and 30 min), RPE breathing (15, 20, 25, and 30 min) and RPE legs (20 and 30 min). Survey responses post-exercise revealed greater feelings of nervousness, tremors, restlessness and stomach distress following caffeine versus placebo. Blunted acute RPE and survey responses suggest participants responded to caffeine ingestion. Caffeine decreased acute RPE during exercise which could partially account for lower session RPE responses. However, decreased session RPE could also reveal a latent analgesic affect of caffeine extending into recovery. Extending the understanding of session RPE could benefit coaches in avoiding overtraining when adjusting training programs.


Assuntos
Cafeína/administração & dosagem , Exercício Físico/psicologia , Percepção/efeitos dos fármacos , Esforço Físico/efeitos dos fármacos , Adulto , Desempenho Atlético/fisiologia , Desempenho Atlético/psicologia , Ciclismo/fisiologia , Ciclismo/psicologia , Exercício Físico/fisiologia , Teste de Esforço , Feminino , Humanos , Masculino , Resistência Física/efeitos dos fármacos , Resistência Física/fisiologia , Placebos , Projetos de Pesquisa , Método Simples-Cego , Fatores de Tempo , Adulto Jovem
5.
BMJ ; 342: d682, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21459975

RESUMO

OBJECTIVE: To examine the effectiveness and cost-effectiveness of group therapy for self harm in young people. DESIGN: Two arm, single (assessor) blinded parallel randomised allocation trial of a group therapy intervention in addition to routine care, compared with routine care alone. Randomisation was by minimisation controlling for baseline frequency of self harm, presence of conduct disorder, depressive disorder, and severity of psychosocial stress. PARTICIPANTS: Adolescents aged 12-17 years with at least two past episodes of self harm within the previous 12 months. Exclusion criteria were: not speaking English, low weight anorexia nervosa, acute psychosis, substantial learning difficulties (defined by need for specialist school), current containment in secure care. Setting Eight child and adolescent mental health services in the northwest UK. INTERVENTIONS: Manual based developmental group therapy programme specifically designed for adolescents who harm themselves, with an acute phase over six weekly sessions followed by a booster phase of weekly groups as long as needed. Details of routine care were gathered from participating centres. MAIN OUTCOME MEASURES: Primary outcome was frequency of subsequent repeated episodes of self harm. Secondary outcomes were severity of subsequent self harm, mood disorder, suicidal ideation, and global functioning. Total costs of health, social care, education, and criminal justice sector services, plus family related costs and productivity losses, were recorded. RESULTS: 183 adolescents were allocated to each arm (total n = 366). Loss to follow-up was low (<4%). On all outcomes the trial cohort as a whole showed significant improvement from baseline to follow-up. On the primary outcome of frequency of self harm, proportional odds ratio of group therapy versus routine care adjusting for relevant baseline variables was 0.99 (95% confidence interval 0.68 to 1.44, P = 0.95) at 6 months and 0.88 (0.59 to 1.33, P = 0.52) at 1 year. For severity of subsequent self harm the equivalent odds ratios were 0.81 (0.54 to 1.20, P = 0.29) at 6 months and 0.94 (0.63 to 1.40, P = 0.75) at 1 year. Total 1 year costs were higher in the group therapy arm (£21,781) than for routine care (£15,372) but the difference was not significant (95% CI -1416 to 10782, P = 0.132). CONCLUSIONS: The addition of this targeted group therapy programme did not improve self harm outcomes for adolescents who repeatedly self harmed, nor was there evidence of cost effectiveness. The outcomes to end point for the cohort as a whole were better than current clinical expectations. Trial registration ISRCTN 20496110.


Assuntos
Psicoterapia de Grupo/economia , Comportamento Autodestrutivo/terapia , Adolescente , Criança , Transtorno da Conduta/complicações , Análise Custo-Benefício , Transtorno Depressivo/complicações , Feminino , Humanos , Masculino , Recidiva , Comportamento Autodestrutivo/economia , Comportamento Autodestrutivo/psicologia , Método Simples-Cego , Estresse Psicológico/complicações , Resultado do Tratamento
7.
J Sports Med Phys Fitness ; 50(3): 243-53, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20842083

RESUMO

AIM: This study investigated the effects of gender on repeated, maximal-intensity intermittent sprint exercise following variable day-to-day recovery periods. METHODS: Sixteen volunteers (8 men, 8 women) performed four trials of high-intensity intermittent sprint exercise consisting of three bouts of eight 30 m sprints (total of 24 sprints). Following completion of the baseline trial, in repeated-measures design, participants were assigned, in counter-balanced order, variable recovery periods of 24, 48, and 72 h whereupon they repeated an identical exercise trial. RESULTS: Results from a series of 4 (trial) x 3 (bout) repeated measures ANOVAs revealed men produced significantly (P < 0.01) faster times throughout all bouts and trials of repeated sprint exercise. Additionally, women exhibited significantly lower (P < 0.05) blood lactate concentration and significantly lower (P < 0.05) decrement in performance, indicating increased resistance to fatigue during repeated exercise sessions. There were no significant differences (P > 0.05) between genders for heart rate or rating of perceived exertion during or following trials. There were no significant differences for overall sprint performance within either gender among trials. CONCLUSION: These results indicate men, while able to produce higher absolute power outputs (i.e., lower sprint time), demonstrate higher decrement scores within a trial compared to women, thus suggesting women may recover faster and fatigue less. Also, gender differences affecting recovery within in a trial were observed to be diminished between trials (i.e., day-to-day recovery) of maximal intermittent sprint work evidenced by the observed stability of performance between trials following various recovery durations.


Assuntos
Fadiga Muscular/fisiologia , Corrida/fisiologia , Análise de Variância , Feminino , Humanos , Lactatos/sangue , Masculino , Recuperação de Função Fisiológica , Fatores Sexuais , Adulto Jovem
8.
Eur J Appl Physiol ; 109(1): 125-31, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20135144

RESUMO

Athletes with spinal cord injury often experience high heat storage due to reduced sweating capacity below the spinal injury. Spray bottle (SB) may be used to apply mist for evaporative cooling during breaks in competitions. This study examined the efficacy of SB during rest breaks. Seven participants, four female and three males, (mean +/- SD age 24 +/- 4.1 year, weight 56.2 +/- 7.0 kg, upper-body VO(2) peak 2.4 +/- 0.6 l/min) volunteered for the study. Participants were paraplegic athletes (T3-T12/L1) with both complete and incomplete lesions. Participants arm-cranked using a ramp protocol in an environment of 21 +/- 1.5 degrees C and 55 +/- 3% rh once using a SB during 1-min rest between 7-min stages of increasing intensity and once without the SB (CON). Mean total work was similar (p = 0.86) for the SB and CON (2495.7 +/- 914.6 vs. 2407.1 +/- 982.3 kJ, respectively). Likewise, the mean work times were similar between trials (27 +/- 6 and 26 +/- 7 min for SB and CON, respectively). Furthermore, there were no significant differences detected between trials for skin temperature, rectal temperature, esophageal temperature (p > 0.05). There were no statistically significant differences detected between trials for RPE (p > 0.05). In conclusion, the application of artificial sweat via SB was ineffective in attenuating the onset of uncompensable heat strain during high-intensity arm exercise in a comfortable environment.


Assuntos
Traumatismos em Atletas/reabilitação , Hipotermia Induzida/métodos , Paraplegia/reabilitação , Traumatismos da Medula Espinal/reabilitação , Suor/fisiologia , Sudorese , Adulto , Traumatismos em Atletas/complicações , Traumatismos em Atletas/fisiopatologia , Basquetebol , Feminino , Humanos , Hipotermia Induzida/instrumentação , Masculino , Paraplegia/complicações , Paraplegia/fisiopatologia , Temperatura Cutânea , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/fisiopatologia , Falha de Tratamento , Água/administração & dosagem , Adulto Jovem
9.
J Occup Environ Hyg ; 6(8): 455-9, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19412861

RESUMO

Ballistic protective helmets can impair heat dissipation. A cooling device in the helmet (cooling pad, CP) could help prevent heat problems in military personnel and potentially enhance comfort. This study examined the effects of CP on rectal and skin temperatures, heart rate, percent change in plasma volume, urine specific gravity, rating of perceived exertion, and other subjective measures while performing light work in a hot environment. It was hypothesized that the CP would act as an insulator to the head, which would not positively affect any physiological variable but could positively affect wearer subjective comfort or temperature. Participants performed a work protocol for approximately 2 hr. A ballistic vest, slacks, short-sleeved button-up shirt, and a ballistic helmet (one trial with CP and one trial without) were worn. Repeated measures analysis of variance (ANOVA) showed no differences (p > 0.05) between wearing and not wearing the CP for any physiological parameter. However, participants perceived the CP as cooler (p = 0.002). Other trends in perceptual data such as thermal strain and helmet comfort indicated the CP felt cooler. However, based on forehead temperature and participant comments, the CP lost its cooling ability relatively quickly (within approximately 30 min).


Assuntos
Dispositivos de Proteção da Cabeça , Militares , Adulto , Temperatura Corporal , Regulação da Temperatura Corporal , Desenho de Equipamento , Frequência Cardíaca , Transtornos de Estresse por Calor/prevenção & controle , Humanos , Masculino , Volume Plasmático , Gravidade Específica , Urina/química
10.
J Robot Surg ; 2(3): 141-3, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27628250

RESUMO

Laparoscopic partial nephrectomy for kidney tumors has demonstrated durable oncologic and functional outcomes. The feasibility of robotic partial nephrectomy (RPN) has been demonstrated in several small, single-institution studies. We performed a large, multi-institutional analysis to determine early oncologic results and perioperative outcomes after RPN. Between October, 2002 and September, 2007, 148 patients underwent RPN at six different centers by nine different primary surgeons for localized renal tumors. Medical and operative records were reviewed for clinical characteristics, pathologic findings, and follow-up information. A total of 148 patients underwent RPN. Mean tumor size was 2.8 cm. Renal hilar clamping was utilized in 120 patients, with a mean warm ischemia time of 27.8 min. Positive surgical margins were identified in six patients (4%), of which two had cautery artifact obscuring the margin after off-clamp cautery excision and one underwent completion radical nephrectomy with no evidence of cancer. There is no evidence of tumor recurrence at mean follow-up of 7.2 months (range 2-54 months) overall, and mean follow-up of 18 months (range 12-23 months) for patients with positive surgical margin. Complications occurred in nine patients (6.1%), including hematoma requiring drainage (n = 1), prolonged ileus (n = 3), pulmonary embolus (n = 2), prolonged urine leak (n = 2), and rhabdomyolysis (n = 1). Two patients underwent open conversion for failure to progress, one patient with morbid obesity and one patient with adhesions from prior ureterolithotomy. Mean hospital stay was 1.9 days. In this multi-institutional series of surgeons beginning their initial experience in RPN, the procedure is a feasible option for minimally invasive, nephron-sparing surgery, with immediate oncologic results and perioperative outcomes comparable with more mature laparoscopic series.

11.
Int J Sports Med ; 29(2): 139-44, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17960503

RESUMO

Dehydration raises heat injury risk and reduces performance [ , , ]. The purpose was to validate the Hydra-Alert Jr (Acumen). The Hydra-Alert was tested in two exercise/clothing conditions. Participants wore it while wearing exercise clothing and exercising at a self-selected intensity (n = 8). Others wore the Hydra-Alert while wearing a ballistic-vest and performing an industrial-protocol (n = 8). For each condition, the Hydra-Alert was tested on two occasions (T1 and T2). The Hydra-Alert was tested against nude weight loss for both conditions. The Hydra-Alert had low test-retest reliability for both conditions (average absolute value of the error between Hydra-Alert outputs of T1 and T2 = 0.08 +/- 0.08 percentage points). With exercise-clothing, the Hydra-Alert evidenced low-moderate correlations between percent nude weight loss and Hydra-Alert output at 20 min (r = 0.59-T1, p = 0.13; r = 0.12-T2, p = 0.78), at 40 min (r = 0.93-T1, p = 0.001; r = 0.63-T2, p = 0.10), and at approximately 2 % weight loss (r = 0.21-T1 and T2, p = 0.61 and 0.62, respectively). The correlation at 40 min during T1 fell during T2 suggesting the Hydra-Alert was inconsistent. When wearing a ballistic-vest, the Hydra-Alert had poor validity (T1: r = - 0.29 [p = 0.48] for weight loss vs. monitor; T2: r = 0.11 [p = 0.80]). At the higher levels of dehydration ( approximately 2 %), the Hydra-Alert error was so high as to render its readings of little value. In some cases, the Hydra-Alert could lead to a false level of security if dehydrated. Therefore, the Hydra-Alert is of little use for those who want to measure their fluid loss while exercising in the heat.


Assuntos
Desidratação/metabolismo , Monitorização Fisiológica/instrumentação , Adulto , Água Corporal/metabolismo , Teste de Esforço/métodos , Humanos , Masculino , Estados Unidos , Equilíbrio Hidroeletrolítico/fisiologia
12.
S. Afr. j. clin. nutr. (Online) ; 21(2): 17-24, 2008.
Artigo em Inglês | AIM (África) | ID: biblio-1270484

RESUMO

"Background :Consumer testing was a prime consideration in developing specific South African food-based dietary guidelines (FBDGs) which were nationally adopted in 2003.Objectives This study aimed to determine the consumer's ability to apply the FBDGs appropriately; in terms of identifying foods/drinks according to the FBDG food categories; perceived importance of and barriers to applying each FBDG; and planning a typical day's meals to reflect the FBDGs. Design A cross-sectional study of 333 women from different cultural and socio-economic backgrounds. Setting KwaZulu-Natal; South Africa. Methods Data collection comprised focus-group discussions (n = 103) and structured individual interviews (n = 230). Results The identification of foods/drinks according to the FBDG food categories reflected a high level of comprehension by participants of these food categories. Participants from all study samples endorsed the importance of applying the FBDGs; predominantly for health reasons. Participants cited barriers to the application of the FBDGs as affordability; availability; household taste preferences; routine food-purchasing habits; time constraints; traditional/ habitual food-preparation methods; and persistent attitudes. Only three FBDGs were mentioned as difficult to apply; namely; ""fruits/ vegetables""; ""foods from animals"" and ""legumes"". Meal plans did reflect the FBDGs; illustrating the flexibility of their use across cultural and socio-economic differences. Conclusions Consumer testing of the FBDGs was mainly positive. The study has highlighted areas of confusion regarding certain concepts; terminology and misconceptions; and has identified barriers to application. These concerns can be addressed through the reformulation and retesting of certain dietary guidelines; and the provision of explanatory consumer information and health-worker training materials."


Assuntos
Estudos Transversais , Alimentos , Mulheres
13.
J Bone Joint Surg Br ; 89(11): 1534-8, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17998197

RESUMO

This study investigated the quality and quantity of healing of a bone defect following intramedullary reaming undertaken by two fundamentally different systems; conventional, using non-irrigated, multiple passes; or suction/irrigation, using one pass. The result of a measured re-implantation of the product of reaming was examined in one additional group. We used 24 Swiss mountain sheep with a mean tibial medullary canal diameter between 8 mm and 9 mm. An 8 mm 'napkin ring' defect was created at the mid-diaphysis. The wound was either surgically closed or occluded. The medullary cavity was then reamed to 11 mm. The Reamer/Irrigator/Aspirator (RIA) System was used for the reaming procedure in groups A (RIA and autofilling) and B (RIA, collected reamings filled up), whereas reaming in group C (Synream and autofilling) was performed with the Synream System. The defect was allowed to auto-fill with reamings in groups A and C, but in group B, the defect was surgically filled with collected reamings. The tibia was then stabilised with a solid locking Unreamed Humerus Nail (UHN), 9.5 mm in diameter. The animals were killed after six weeks. After the implants were removed, measurements were taken to assess the stiffness, strength and callus formation at the site of the defect. There was no significant difference between healing after conventional reaming or suction/irrigation reaming. A significant improvement in the quality of the callus was demonstrated by surgically placing captured reamings into the defect using a graft harvesting system attached to the aspirator device. This was confirmed by biomechanical testing of stiffness and strength. This study suggests it could be beneficial to fill cortical defects with reaming particles in clinical practice, if feasible.


Assuntos
Calo Ósseo , Fixação Intramedular de Fraturas/métodos , Animais , Estudos de Viabilidade , Consolidação da Fratura , Modelos Animais , Ovinos
14.
J Sports Med Phys Fitness ; 47(1): 18-24, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17369793

RESUMO

AIM: The potential influence of a hotter vs cooler environment on ratings of perceived exertion (RPE) estimations during longer duration exercise is not well-understood. This study compared overall and differentiated RPEs during cycling in 18 degrees C vs 30 degrees C wet bulb globe temperature (WBGT). METHODS: Male volunteers (n=16) completed a maximal cycling trial (60 rev . min(-1), 25 Watts . min(-1)) to determine VO(2) max and ventilatory threshold (VT) before completing 2 (counterbalanced) longer duration cycling trials. At 30 degrees C WBGT (30C) and 18 degrees C WBGT (18C), subjects cycled 60 min (60 rev . min(-1), 90% individualized VT). Heart rate (HR, b . min(-1)) and rectal temperature (Tre, degrees C) were recorded every 5 min with corresponding RPE-overall (RPE-O), RPE-legs (RPE-L) and RPE-chest (RPE-C) estimations. RESULTS: HR was not significantly different at 5 min but was greater (P<0.05) for 30C at all other time points. During 30C, Tre was significantly greater (25, 30, 35, 40, 45, 50, 55 and 60 min), RPE-O was significantly greater (5, 40, 45, 50, 55 and 60 min), RPE-L was significantly greater (55 and 60 min) and RPE-C was significantly greater (35, 40, 45, 50, 55 and 60 min). CONCLUSIONS: Greater cardiovascular (HR) and thermal (Tre) strain partially explain greater perceptual ratings during 30C. Discernible RPE differences resulted mid-way through 60 min cycling with minimal differences initially. Results suggest RPEs are magnified in a 30 degrees C (vs 18 degrees C) environment beyond 30 min duration. Additionally, a 30 degrees C environment resulted in a less pronounced impact on RPE-L (vs RPE-C and RPE-O).


Assuntos
Esforço Físico/fisiologia , Temperatura , Adulto , Análise de Variância , Ciclismo/fisiologia , Regulação da Temperatura Corporal/fisiologia , Teste de Esforço , Frequência Cardíaca/fisiologia , Humanos , Masculino , Consumo de Oxigênio/fisiologia
15.
J Sports Med Phys Fitness ; 47(1): 33-9, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17369795

RESUMO

AIM: Ratings of perceived exertion (RPE) have been shown similar across subjects of varying fitness when estimations are made at relative physiological criteria. Because few studies have investigated the influence of fitness during longer duration bouts, the current investigation compared overall exertion (RPE-O), leg exertion (RPE-L) and breathing/chest exertion (RPE-C) between aerobically fit and unfit subjects. METHODS: Aerobically fit (61.6+/-2.5 mL . kg . min(-1)) (n=7) and unfit (41.8+/-6.3 mL . kg . min(-1)) (n=6) males completed a maximal bike test and then cycled for 60 min at approximately 90% of individualized ventilatory threshold (VT) (V(E)/VO(2) vs V(E)/VCO(2)). Heart rate (HR, b . min(-1)), rectal temperature (Tre, degrees C) and RPE estimations were collected during graded testing every 2 min and every 10 min during 60 min bouts. RESULTS: During graded testing, RPE estimations at VT were not significantly different between groups. During 60 min cycling, HR and Tre were not significantly different between groups. Also, there were no significant differences for HR increase (HR 60 min HR 5 min) or Tre increase (Tre 60 min Tre 5 min). Interactions between groups were; RPE-O (P=0.09), RPE-L (P=0.06) and RPE-C (P=0.19). Analyses suggest groups experienced similar relative cardiovascular (HR) and thermal (Tre) strain. CONCLUSIONS: Although RPE responses between groups were similar at 10, 20 and 30 min, RPE drift was magnified in aerobically unfit subjects (vs aerobically fit subjects) beyond the 30 min point. Contrary to previous studies suggesting aerobic fitness does not influence RPE, current results show lower aerobic fitness magnifies RPE at individualized relative intensities when cycling extends beyond 30 min.


Assuntos
Ciclismo/fisiologia , Percepção/fisiologia , Esforço Físico/fisiologia , Aptidão Física/fisiologia , Adulto , Análise de Variância , Teste de Esforço , Humanos , Masculino , Consumo de Oxigênio/fisiologia
16.
Birth ; 33(2): 154-8, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16732782

RESUMO

PREFACE: Normal childbirth has become jeopardized by inexorably rising interventions around the world. In many countries and settings, cesarean surgery, labor induction, and epidural analgesia continue to increase beyond all precedent, and without convincing evidence that these actions result in improved outcomes (1,2). Use of electronic fetal monitoring is endemic, despite evidence of its ineffectiveness and consequences for most parturients (1,3); ultrasound examinations are too often done unnecessarily, redundantly, or for frivolous rather than indicated reasons (4); episiotomies are still routine in many settings despite clear evidence that this surgery results in more harm than good (5); and medical procedures, unphysiological positions, pubic shaving and enemas, intravenous lines, enforced fasting, drugs, and early mother-infant separation are used unnecessarily (1). Clinicians write and talk about the ideal of evidence-based obstetrics, but do not practice it consistently, if at all. Why do women go along with this stuff? In this Roundtable Discussion, Part 1, we asked some maternity care professionals and advocates to discuss this question.


Assuntos
Parto Obstétrico/métodos , Medicina Baseada em Evidências , Aceitação pelo Paciente de Cuidados de Saúde , Defesa do Paciente , Qualidade da Assistência à Saúde , Analgesia Epidural/estatística & dados numéricos , Cesárea/estatística & dados numéricos , Parto Obstétrico/efeitos adversos , Episiotomia/efeitos adversos , Episiotomia/estatística & dados numéricos , Feminino , Monitorização Fetal/estatística & dados numéricos , Humanos , Trabalho de Parto Induzido/estatística & dados numéricos , Relações Médico-Paciente , Gravidez
17.
Eur J Appl Physiol ; 94(1-2): 145-50, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15702340

RESUMO

This study examined the association of blood lactate concentration [La] and heart rate (HR) with ratings of perceived exertion (RPE) during 60 min of steady workload cycling. Physically active college-aged subjects (n = 14) completed an exhaustive cycling test to determine VO(2) (peak) and lactate threshold (2.5 mmol l(-1)). Subjects then cycled for 60 min at the power output associated with 2.5 mmol l(-1) [LA]. HR, [LA], RPE-overall, RPE-legs and RPE-chest were recorded at 5, 10, 20, 30, 40, 50 and 60 min. The 60-min trials were below maximal lactate steady state, with peak lactate concentration occurring at 20 min after which [LA] declined. The 20-min point was therefore considered pivotal, and data at other points were compared to this time point. Repeated measures ANOVA with simple contrasts (alpha = 0.05) showed (a) [LA] at 40, 50 and 60 min was significantly lower than at 20 min, (b) RPE-O and RPE-L were significantly greater at 30, 40, 50 and 60 min than at 20 min, (c) RPE-C was significantly greater at 40, 50 and 60 min than at 20 min, and (d) HR was significantly greater at 30, 40, 50 and 60 min than at 20 min. Significant (P < 0.05) positive correlations were found between HR and RPE-O (r = 0.43), RPE-L (r = 0.48) and RPE-C (r = 0.41) while correlations for [LA]-HR (r = 0.13) and [LA]-RPE (RPE-O: r = -0.11, RPE-L: r = 0.01, RPE-C: r = -0.06) were weak and non-significant. There is a dissociation of RPE and [LA] owing to RPE drift and lactate kinetics in longer duration sub-maximal exercise. Apparently, [LA] is not a strong RPE mediator during extended cycling.


Assuntos
Ciclismo/fisiologia , Frequência Cardíaca/fisiologia , Ácido Láctico/sangue , Consumo de Oxigênio/fisiologia , Resistência Física/fisiologia , Esforço Físico/fisiologia , Adulto , Limiar Anaeróbio/fisiologia , Humanos , Masculino , Estatística como Assunto
18.
Health Technol Assess ; 8(33): iii, ix-x, 1-109, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15298822

RESUMO

OBJECTIVES: To address five broad questions concerned with knowledge, anxiety, factors associated with participation/non-participation in screening programmes and the long-term sequelae of false-positive, true-positive in newborns and true-negative results. DATA SOURCES: Five electronic databases, two journals and attempts were made to locate unpublished work. REVIEW METHODS: This review started from a substantial literature base that provided the basis for (a) scoping the literature, (b) informing search strategy terms and (c) identifying preliminary article inclusion and exclusion criteria. The main eligibility criteria were: any screening programme aimed at pregnant women or newborn babies that included a 'genetic' target condition, this included chromosomal anomalies; any study that reported psychosocial data collected directly from parents. The data extraction form developed for this study elicited data from the selected studies. The data were entered into a database, which provided a summary of the included papers. RESULTS: A total of 288 candidate publications were identified, 106 of which were eligible: 78 were concerned with antenatal screening and 28 with newborn screening. It was found that levels of knowledge adequate for decision-making were not being achieved despite information leaflets and videos having some effect. Studies that have succeeded in increasing knowledge have not observed a corresponding increase in anxiety, although some anxiety might be an appropriate response and may aid coping and decision-making. Anxiety is clearly raised in women receiving positive screening results, especially young women. However, evidence is lacking of a beneficial (i.e. reassuring) effect of receiving a screen-negative result. Anxiety in screen-positive women falls on receipt of subsequent reassuring results, but some residual anxiety may remain. A minority (perhaps up to 30%) of women receiving a screen-positive result in pregnancy expressed regret about their screening decision. Uptake of neonatal screening has been treated as a 'given' and not as a research topic. CONCLUSIONS: The results of this review have many implications for the work of the National Screening Committee. The most pressing of these, in order of priority, relate to: the inadequacy of current procedures for achieving informed consent; the cost of providing a satisfactory service; the unmet needs of 'false-positives', and the unmet needs of women's partners, particularly in carrier screening. It is suggested that research is conducted on the above four topics in order to fill gaps in the evidence base that relate to screening technologies which have been available for many years. In addition, future screening programmes will create a new list of research questions, based on the same main agenda but applied to new areas, for example, new conditions such as haemoglobinopathies and fragile X syndrome; new client groups such as young women and minority ethnic groups; and new testing modalities such as ultrasound.


Assuntos
Testes Genéticos/psicologia , Triagem Neonatal/psicologia , Diagnóstico Pré-Natal/psicologia , Adulto , Ansiedade , Feminino , Humanos , Recém-Nascido , Gravidez , Reino Unido
19.
J Sports Sci ; 22(4): 321-7, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15161105

RESUMO

Sweat lactate reflects eccrine gland metabolism. However, the metabolic tendencies of eccrine glands in a hot versus thermoneutral environment are not well understood. Sixteen male volunteers completed a maximal cycling trial and two 60-min cycling trials [30 degrees C = 30 +/- 1 degrees C and 18 degrees C = 18 +/- 1 degrees C wet bulb globe temperature (WBGT)]. The participants were requested to maintain a cadence of 60 rev min(-1) with the intensity individualized at approximately 90% of the ventilatory threshold. Sweat samples at 10, 20, 30, 40, 50 and 60 min were analysed for lactate concentration. Sweat rate at 30 degrees C (1380 +/- 325 ml x h(-1)) was significantly greater (P < 0.05) than at 18 degrees C (632 +/- 311 ml x h(-1)). Sweat lactate concentration was significantly greater (P < 0.05) at each time point during the 18 degrees C trial, with values between trials tending to converge across time. During the 30 degrees C trial, both heart rate (20, 30, 40, 50 and 60 min) and rectal temperature (30, 40, 50 and 60 min) were significantly higher than in the 18 degrees C trial. Higher sweat lactate concentrations coupled with lower sweat rates may indicate a greater relative contribution of oxygen-independent metabolism within eccrine glands during exercise at 18 degrees C. Decreases in sweat lactate concentration across time suggest either greater dilution due to greater sweat volume or increased reliance on aerobic metabolism within eccrine glands. The convergence of lactate concentrations between trials may indicate that time-dependent modifications in sweat gland metabolism occur at different rates contingent partially on environmental conditions.


Assuntos
Ciclismo/fisiologia , Glândulas Écrinas/metabolismo , Lactatos/análise , Sudorese/fisiologia , Adulto , Análise de Variância , Regulação da Temperatura Corporal/fisiologia , Teste de Esforço , Humanos , Masculino , Esforço Físico , Aptidão Física , Estudos Prospectivos , Suor/química , Temperatura
20.
Eur J Appl Physiol ; 91(1): 1-6, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14551778

RESUMO

Sweat lactate indirectly reflects eccrine gland metabolism. However the potential influence of aerobic fitness on sweat lactate is not well-understood. Six males with high aerobic fitness [peak oxygen consumption ( VO(2)peak): 61.6 (2.5) ml.kg(-1).min(-1)] and seven males with low aerobic fitness [ VO(2)peak: 41.8 (6.4) ml.kg(-1).min(-1)] completed a maximal exertion cycling trial followed on a different day by 60 min of cycling (60 rev.min(-1)) in a 30 degrees C wet bulb globe temperature environment. Intensity was individualized at 90% of the ventilatory threshold ( V(E)/ VO(2) increase with no concurrent V(E)/ VCO(2) increase). Sweat samples were collected from the lumbar region every 10 min and analyzed for lactate concentration. Sweat rate (SR) was significantly greater ( p<0.05) for subjects with a high [1445 (254) ml.h(-1)] versus a low [1056 (261) ml.h(-1)] fitness level. Also, estimated total lactate excretion (SRxmean sweat lactate concentration) was marginally greater ( p=0.2) in highly fit males. However, repeated measures ANOVA showed no significant differences ( p>0.05) between groups for sweat lactate concentration at any time point. Current results show highly fit (vs. low fitness level) males have a greater sweat rate which is consistent with previous literature. However aerobic fitness and subsequent variations in SR do not appear to influence sweat lactate concentrations in males.


Assuntos
Ácido Láctico/análise , Aptidão Física/fisiologia , Suor/química , Adulto , Regulação da Temperatura Corporal , Glândulas Écrinas/química , Humanos , Masculino
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