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1.
J Strength Cond Res ; 36(9): 2602-2609, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-33651728

RESUMEN

ABSTRACT: Thomas, C, Delfour-Peyrethon, R, Dorel, S, and Hanon, C. Positive effects of pre-exercise metabolic alkalosis on perceived exertion and post-exercise squat jump performance in world-class cyclists. J Strength Cond Res 36(9): 2602-2609, 2022-This study aimed to determine the effects of pre-exercise alkalosis in world-class cyclists on their general (rate of perceived exertion [RPE]) and local (category-ratio scale [CR10]) perceived rates of exertion and acid-base status during 2 types of training sessions. Eight world-class cyclists ingested either sodium bicarbonate (BIC) or a placebo (PLA) in a double-blind and randomized order before performing 4 × 1,000 m constant-power sprints (CP) or 3 × 500 m all-out sprints (AO), with 20 minutes of recovery time between each session. For AO, the performance was assessed through the cycling sprint velocity and a squat jump test during recovery. During both tests, RPE, CR10, and acid-base status were measured. Sodium bicarbonate ingestion was effective in inducing pre-exercise alkalosis, compared with a PLA ( p < 0.05). During CP, performance and RPE were the same for BIC and PLA ( p > 0.05) with no time effect. The CR10 increased for the last sprint in PLA ( p < 0.05) but was attenuated in BIC (BIC: 6 vs. PLA: 8.2; p < 0.05), whereas there was no difference in acid-base status. During AO, RPE and CR10 increased with time, with no BIC effect, whereas blood lactate concentration was different ( p < 0.05). Sodium bicarbonate supplementation had no effect on overall repeated sprints ( p > 0.05). However, world-class athletes responded to BIC with higher squat jump performance than the PLA condition after AO ( p < 0.05). Our results suggest a positive influence of pre-exercise alkalosis in world-class cyclists on local perception of efforts after constant load sprints and an attenuation of muscle power output decline postsprint, as evidenced by improved squat jump performance after all-out cycling effort.


Asunto(s)
Alcalosis , Rendimiento Atlético , Rendimiento Atlético/fisiología , Prueba de Esfuerzo/métodos , Humanos , Ácido Láctico , Esfuerzo Físico/fisiología , Poliésteres/farmacología , Bicarbonato de Sodio/farmacología
2.
J Sports Sci Med ; 21(3): 426-434, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36157388

RESUMEN

To propose a new Cardiopulmonary Exercise Test with Elastic Resistance (CPxEL) and compare the physiological responses to conventional cardiopulmonary exercise test (CPx) performed on a treadmill. In addition, we tested the reproducibility of the CPxEL. Twenty-four physically active participants completed the CPx (first session) and CPxEL twice (second and third sessions) interspersed by seven days. A treadmill protocol with increments of 1km·h-1 every minute until exhaustion was used in CPx. The CPxEL consisted of performing alternating steps back-and-forth against an elastic resistance attached to a belt and an incremental protocol with 1 stage (S) per minute following a cadence of 200 bpm controlled by a metronome in an 8-stage rubber mat. First analysis: first ventilatory threshold (VT1) occurred at 69.7% and 75.3% of maximal heart rate (HRmax) and 53.5% and 65.7% of maximal oxygen consumption (V̇O2max). Second VT (VT2) occurred at 93.3% and 96.8% of the HRmax and 87.0% and 96.9% of V̇O2max for CPx and CPxEL, respectively. At exhaustion, V̇O2max, perceived exertion (BORG-CR10 and OMNI-RES EB), and test duration presented lower values for CPxEL (P < 0.05). Second analysis: VT1 occurred at warm-up (S0) (P = 0.731), VT2 occurred at S5 (P = 0.912), and the exhaustion occurred at S6 and S7 (P = 0.271) for CPxEL and retest, respectively. The intraclass correlation coefficient (ICC) for V̇O2max was 0.921 and for HRmax was 0.930. The CPxEL has good test-retest reproducibility and represents a possible and interesting add-on to determine maximal oxygen consumption, maximal heart rate, and second ventilatory threshold without using traditional ergometers.


Asunto(s)
Prueba de Esfuerzo , Goma , Prueba de Esfuerzo/métodos , Frecuencia Cardíaca/fisiología , Humanos , Consumo de Oxígeno/fisiología , Reproducibilidad de los Resultados
3.
Cytokine ; 137: 155347, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33128925

RESUMEN

The purpose of this study was to compare the effects of exercise in cold-dry (CC, -20 °C, RH 40%) and normal conditions (NC, 20 °C, RH 60%) on salivary levels of pro-inflammatory and regulatory cytokines (IL-1RA, IL-8, and IL-5) and the airway response (FEV1 and FVC) in young healthy males. Participants (n = 11, age: 23.6 ± 3.1 years) completed an incremental to maximal exercise test and two exercise sessions in an environmental chamber in random order. Saliva samples were collected, and spirometry was performed prior to the maximal exercise test as well as pre and post-exercise for the CC and NC sessions. IL-8 levels increased from pre to post-exercise during NC but not during CC; the opposite trend was observed for IL-1RA. These data may provide insight into pathways associated with the development of airway hyperresponsiveness in healthy athletes.


Asunto(s)
Frío , Ejercicio Físico/fisiología , Humedad , Proteína Antagonista del Receptor de Interleucina 1/metabolismo , Interleucina-8/metabolismo , Saliva/metabolismo , Adulto , Estudios Cruzados , Prueba de Esfuerzo/métodos , Humanos , Masculino , Pruebas de Función Respiratoria/métodos , Espirometría/métodos , Adulto Joven
4.
Eur J Appl Physiol ; 121(10): 2849-2858, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34173862

RESUMEN

PURPOSE: Carbohydrate (CHO) mouth rinsing (MR) prior to exercise has been shown to elicit enhanced performance and energy availability in some studies. Previous literature has concentrated on examining CHO MR strategies for improving aerobic endurance performance in younger athletic adults. Knowledge of the impact of CHO MR on functional performance in older adults is scarce. The purpose of this investigation was to determine if CHO MR would improve 6-min walk test (6MWT) performance, perceived exertion, and blood glucose responses in older adults. METHOD: Thirty-three individuals (16 males, 17 females), age ≥ 70 years performed two 6MWT trials, one of which utilized a 6.4% maltodextrin CHO MR and one of which utilized a placebo MR. Participants held the MR in their mouth for 20 s prior to the 6MWT, and trials occurred in a counterbalanced fashion. Total distance walked and rating of perceived exertion (RPE) were recorded upon completion of each 6MWT. Heart rate (HR), peripheral blood oxygen saturation (SpO2), systolic and diastolic blood pressures (BP), blood glucose, and blood lactate were measured before and after each 6MWT. RESULT: CHO MR did not alter the response of any study parameter compared to the placebo MR (p = 0.13-0.94). HR, systolic BP, and blood lactate increased and SpO2 decreased across time (p < 0.01). CONCLUSION: A 6.4% maltodextrin CHO MR did not alter total distance walked, perceived exertion, or other physiological responses elicited by the 6MWT in older adults.


Asunto(s)
Envejecimiento/fisiología , Glucemia/metabolismo , Ejercicio Físico/fisiología , Antisépticos Bucales , Saturación de Oxígeno/fisiología , Anciano , Anciano de 80 o más Años , Rendimiento Atlético/fisiología , Prueba de Esfuerzo/métodos , Femenino , Humanos , Masculino , Resistencia Física/fisiología , Prueba de Paso/métodos
5.
J Physiol ; 597(14): 3673-3685, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31115056

RESUMEN

KEY POINTS: The effect of combined inspiratory and expiratory muscle training on resting and reflexive cardiac function, as well as exercise capacity, in individuals with cervical spinal cord injury (SCI) is presently unknown. Six weeks of combined inspiratory and expiratory muscle training enhances both inspiratory and expiratory muscle strength in highly-trained athletes with cervical SCI with no significant effect on lung function. There was a significant decrease in left-ventricular filling and stroke volume at rest in response to 45° head-up tilt, which is irreversible by respiratory muscle training. Combined inspiratory and expiratory muscle training increased peak aerobic work rate and reduced end-expiratory lung volumes during exercise, which may have implications for left-ventricular filling during exercise. ABSTRACT: To investigate the pulmonary, cardiovascular and exercise responses to combined inspiratory and expiratory respiratory muscle training (RMT) in athletes with tetraplegia, six wheelchair rugby athletes (five males and one female, aged 33 ± 5 years) completed 6 weeks of pressure threshold RMT, 2 sessions day-1 on 5 days week-1 . Resting pulmonary and cardiac function, exercise capacity, exercising lung volumes and field-based exercise performance were assessed at pre-RMT, post-RMT and after a 6-week no RMT period. RMT enhanced maximal inspiratory (pre- vs. post-RMT: -76 ± 15 to -106 ± 23 cmH2 O, P = 0.002) and expiratory (59 ± 26 to 73 ± 32 cmH2 O, P = 0.007) mouth pressures, as well as peak expiratory flow (6.74 ± 1.51 vs. 7.32 ± 1.60 L/s, P < 0.04). Compared to pre-RMT, peak work rate was higher at post-RMT (60 ± 23 to 68 ± 22 W, P = 0.003), whereas exercising end-expiratory lung volumes were reduced (P < 0.017). Peak oxygen uptake increased in all athletes at post-RMT (1.24 ± 0.40 vs. 1.40 ± 0.50 l min-1 , P = 0.12). After 6 weeks of no RMT all indices returned towards baseline, with peak work rate (P = 0.037), peak oxygen uptake (P = 0.041) and end-expiratory lung volume (P < 0.034) being significantly lower at follow-up than at post-RMT. There was a significant decrease in left-ventricular end-diastolic volume and stroke volume in response to 45° head-up tilt (P = 0.030 and 0.021, respectively); however, all cardiac indices in both supine and tilted positions were unchanged by RMT. Our findings demonstrate the efficacy of RMT with respect to enhancing respiratory muscle strength, lowering exercising lung volumes and increasing exercise capacity. Although the precise mechanisms by which RMT may enhance exercise capacity remain unclear, our data suggest that it is probably not the result of a direct cardiac adaptation associated with RMT.


Asunto(s)
Médula Cervical/fisiopatología , Tolerancia al Ejercicio/fisiología , Ejercicio Físico/fisiología , Resistencia Física/fisiología , Músculos Respiratorios/fisiopatología , Traumatismos de la Médula Espinal/fisiopatología , Adulto , Atletas , Ejercicios Respiratorios/métodos , Prueba de Esfuerzo/métodos , Femenino , Humanos , Pulmón/fisiopatología , Masculino , Fuerza Muscular/fisiología , Consumo de Oxígeno/fisiología , Respiración , Pruebas de Función Respiratoria/métodos , Volumen de Ventilación Pulmonar/fisiología
6.
Exp Physiol ; 104(12): 1829-1840, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31583757

RESUMEN

NEW FINDINGS: What is the central question of this study? Breath-by-breath gas exchange analysis during treadmill exercise can be disturbed by different breathing patterns depending on cadence, and the flow sensor might be subjected to variable mechanical stress. It is still unclear whether the outcomes of the gas exchange algorithms can be affected by running at different speeds. What is the main finding and its importance? Practically, the three investigated breath-by-breath algorithms ('Wessel', 'expiration-only' and 'independent breath') provided similar average gas exchange values for steady-state conditions. The 'independent breath' algorithm showed the lowest breath-by-breath fluctuations in the gas exchange data compared with the other investigated algorithms, both at steady state and during incremental exercise. ABSTRACT: Recently, a new breath-by-breath gas exchange calculation algorithm (called 'independent breath') was proposed. In the present work, we aimed to compare the breath-by-breath O2 uptake ( V̇O2 ) values assessed in healthy subjects undergoing a running protocol, as calculated applying the 'independent breath' algorithm or two other commonly used algorithms. The traces of respiratory flow, O2 and CO2 fractions, used by the calculation algorithms, were acquired at the mouth on 17 volunteers at rest, during running on a treadmill at 6.5 and 9.5 km h-1 , and thereafter up to volitional fatigue. Within-subject averages and standard deviations of breath-by-breath V̇O2 were calculated for steady-state conditions; the V̇O2 data of the incremental phase were analysed by means of linear regression, and their root mean square was assumed to be an index of the breath-by-breath fluctuations. The average values obtained with the different algorithms were significantly different (P < 0.001); nevertheless, from a practical point of view the difference could be considered 'small' in all the investigated conditions (effect size <0.3). The standard deviations were significantly lower for the 'independent breath' algorithm (post hoc contrasts, P < 0.001), and the slopes of the relationships with the corresponding data yielded by the other algorithms were <0.70. The root mean squares of the linear regressions calculated for the incremental phase were also significantly lower for the 'independent breath' algorithm, and the slopes of the regression lines with the corresponding values obtained with the other algorithms were <0.84. In conclusion, the 'independent breath' algorithm yielded the least breath-by-breath O2 uptake fluctuation, both during steady-state exercise and during incremental running.


Asunto(s)
Algoritmos , Prueba de Esfuerzo/métodos , Consumo de Oxígeno/fisiología , Intercambio Gaseoso Pulmonar/fisiología , Mecánica Respiratoria/fisiología , Carrera/fisiología , Adulto , Femenino , Humanos , Masculino , Distribución Aleatoria
7.
Exp Physiol ; 104(2): 180-188, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30462876

RESUMEN

NEW FINDINGS: What is the central question of this study? Increased respiratory muscle activation is associated with neural and cardiovascular consequences via the respiratory muscle metaboreflex. Does increased sympathetic vasoconstriction originating from the respiratory musculature elicit a reduction in blood flow to an inactive limb in order to maintain blood flow to an active limb? What is the main finding and its importance? Arm blood flow was reduced whereas leg blood flow was preserved during mild leg exercise with inspiratory resistance. Blood flow to the active limb is maintained via sympathetic control of blood flow redistribution when the respiratory muscle-induced metaboreflex is activated. ABSTRACT: The purpose of this study was to elucidate the effect of increasing inspiratory muscle work on blood flow to inactive and active limbs. Healthy young men (n = 10, 20 ± 2 years of age) performed two bilateral dynamic knee-extension and knee-flexion exercise tests at 40% peak oxygen uptake for 10 min. The trials consisted of spontaneous breathing for 5 min followed by voluntary hyperventilation either with or without inspiratory resistance for 5 min (40% of maximal inspiratory mouth pressure, inspiratory duty cycle of 50% and a breathing frequency of 40 breaths min-1 ). Mean arterial blood pressure was acquired using finger photoplethysmography. Blood flow in the brachial artery (inactive limb) and in the femoral artery (active limb) were monitored using Doppler ultrasound. Mean arterial blood pressure during exercise was higher (P < 0.05) with inspiratory resistance (121 ± 7 mmHg) than without resistance (99 ± 5 mmHg). Brachial artery blood flow increased during exercise without inspiratory resistance (120 ± 31 ml min-1 ) compared with the resting level, whereas it was attenuated with inspiratory resistance (65 ± 43 ml min-1 ). Femoral artery blood flow increased at the onset of exercise and was maintained throughout exercise without inspiratory resistance (2576 ± 640 ml min-1 ) and was unchanged when inspiratory resistance was added (2634 ± 659 ml min-1 ; P > 0.05). These results suggest that sympathetic control of blood redistribution to active limbs is facilitated, in part, by the respiratory muscle-induced metaboreflex.


Asunto(s)
Ejercicio Físico/fisiología , Extremidades/fisiología , Músculo Esquelético/fisiología , Flujo Sanguíneo Regional/fisiología , Músculos Respiratorios/fisiología , Trabajo Respiratorio/fisiología , Adulto , Presión Arterial/fisiología , Prueba de Esfuerzo/métodos , Arteria Femoral/metabolismo , Arteria Femoral/fisiología , Humanos , Inhalación/fisiología , Rodilla/fisiología , Masculino , Fatiga Muscular/fisiología , Músculo Esquelético/metabolismo , Oxígeno/metabolismo , Reflejo/fisiología , Respiración , Músculos Respiratorios/metabolismo , Descanso/fisiología , Sistema Nervioso Simpático/metabolismo , Sistema Nervioso Simpático/fisiología , Resistencia Vascular/fisiología , Adulto Joven
8.
J Strength Cond Res ; 31(11): 3077-3082, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28033122

RESUMEN

Bruce, LM and Moule, SJ. Validity of the 30-15 intermittent fitness test in subelite female athletes. J Strength Cond Res 31(11): 3077-3082, 2017-The purpose of this study was to assess the suitability of the 30-15 Intermittent Fitness Test (IFT) as a test in netball using female athletes. Twenty-six female subelite netballers (mean age = 19.7 ± 4.6 years, mean height = 176.0 ± 6.1 cm, mean body mass = 69.7 ± 9.3 kg) completed the yo-yo intermittent recovery test level 1 (yo-yo IRT1) and the 30-15 IFT. Participants performed both assessments 1 week apart before the intervention and both tests 1 week apart after the training intervention (for a total of 4 testing sessions). A 6-week training intervention occurred between the test occasions. Pearson's correlations revealed significant very strong relationships between the 30-15 IFT and yo-yo IRT on both test occasions (test occasion 1: r = 0.71, p = 0.003 [95% confidence interval {CI} 0.35-0.89], magnitude of effect, most likely; test occasion 2: r = 0.72, p = 0.001 [95% CI: 0.42-0.88], magnitude of effect, most likely). Repeated-measures analysis of variances examining the effect of position on performance changes revealed main effects for test occasion and a position × test occasion interaction for both the 30-15 IFT and the yo-yo IRT1 (30-15 IFT: test occasion [F(1,14) = 28.68, p = 0.001, ηp = 0.67], position × test occasion interaction [F(2,14) = 9.38, p = 0.003, ηp = 0.57]; yo-yo IRT1: test occasion [F(1,15) = 11.72, p = 0.004, ηp = 0.44], position × test occasion interaction [F(2,15) = 9.96, p = 0.002, ηp = 0.57]). Results show that the 30-15 IFT is a suitable test for female netballers as it was able to detect improvements in performance after a training intervention, in addition to having a very strong significant relationship with the yo-yo IRT1.


Asunto(s)
Atletas , Rendimiento Atlético/fisiología , Prueba de Esfuerzo/métodos , Ejercicio Físico/fisiología , Adolescente , Adulto , Femenino , Humanos , Resistencia Física , Aptitud Física , Carrera/fisiología , Medicina Deportiva , Adulto Joven
9.
Acta Orthop ; 88(3): 275-281, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28067099

RESUMEN

Background and purpose - Implant inducible micromotions have been suggested to reflect the quality of the fixation interface. We investigated the usability of dynamic RSA for evaluation of inducible micromotions of the Oxford Unicompartmental Knee Arthroplasty (UKA) tibial component, and evaluated factors that have been suggested to compromise the fixation, such as fixation method, component alignment, and radiolucent lines (RLLs). Patients and methods - 15 patients (12 men) with a mean age of 69 (55-86) years, with an Oxford UKA (7 cemented), were studied after a mean time in situ of 4.4 (3.6-5.1) years. 4 had tibial RLLs. Each patient was recorded with dynamic RSA (10 frames/second) during a step-up/step-down motion. Inducible micromotions were calculated for the tibial component with respect to the tibia bone. Postoperative component alignment was measured with model-based RSA and RLLs were measured on screened radiographs. Results - All tibial components showed inducible micromotions as a function of the step-cycle motion with a mean subsidence of up to -0.06 mm (95% CI: -0.10 to -0.03). Tibial component inducible micromotions were similar for cemented fixation and cementless fixation. Patients with tibial RLLs had 0.5° (95% CI: 0.18-0.81) greater inducible medio-lateral tilt of the tibial component. There was a correlation between postoperative posterior slope of the tibial plateau and inducible anterior-posterior tilt. Interpretation - All patients had inducible micromotions of the tibial component during step-cycle motion. RLLs and a high posterior slope increased the magnitude of inducible micromotions. This suggests that dynamic RSA is a valuable clinical tool for the evaluation of functional implant fixation.


Asunto(s)
Artroplastia de Reemplazo de Rodilla/métodos , Articulación de la Rodilla/diagnóstico por imagen , Prótesis de la Rodilla , Falla de Prótesis/etiología , Anciano , Artroplastia de Reemplazo de Rodilla/efectos adversos , Fenómenos Biomecánicos , Cementos para Huesos , Cementación , Prueba de Esfuerzo/métodos , Femenino , Estudios de Seguimiento , Humanos , Articulación de la Rodilla/fisiopatología , Articulación de la Rodilla/cirugía , Prótesis de la Rodilla/efectos adversos , Masculino , Persona de Mediana Edad , Movimiento (Física) , Medición de Resultados Informados por el Paciente , Diseño de Prótesis , Análisis Radioestereométrico/métodos , Tibia/diagnóstico por imagen
10.
J Sports Sci ; 34(9): 852-5, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26238160

RESUMEN

Investigations in the 1990s evaluated the influence of breathing assemblies on respiratory variables at rest and during exercise; however, research on new models of breathing assemblies is lacking. This study compared metabolic gas analysis data from a mouthpiece with a noseclip (MOUTH) and a face mask (MASK). Volunteers (7 males, 7 females; 25.1 ± 2.7 years) completed two maximal treadmill tests within 1 week, one MOUTH and one MASK, in random order. The difference in maximal oxygen consumption (VO2max) between MOUTH (52.7 ± 11.3 ml · kg(-1) · min(-1)) and MASK (52.2 ± 11.7 ml · kg(-1) · min(-1)) was not significant (P = 0.53). Likewise, the mean MOUTH-MASK differences in minute ventilation (VE), fraction of expired oxygen (FEO2) and carbon dioxide (FECO2), respiration rate (RR), tidal volume (Vt), heart rate (HR), and rating of perceived exertion (RPE) at maximal and submaximal intensities were not significant (P > 0.05). Furthermore, there was no systematic bias in the error scores (r = -0.13, P = 0.66), and 12 of the 14 participants had a VO2max difference of ≤3 ml · kg(-1) · min(-1) between conditions. Finally, there was no clear participant preference for using the MOUTH or MASK. Selection of MOUTH or MASK will not affect the participant's gas exchange or breathing patterns.


Asunto(s)
Dióxido de Carbono/análisis , Prueba de Esfuerzo/métodos , Oxígeno/análisis , Respiración , Descanso/fisiología , Carrera/fisiología , Adulto , Prueba de Esfuerzo/instrumentación , Cara , Fatiga , Femenino , Frecuencia Cardíaca , Humanos , Masculino , Boca , Consumo de Oxígeno , Esfuerzo Físico , Adulto Joven
11.
J Strength Cond Res ; 30(5): 1409-15, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26466128

RESUMEN

Besides injury prevention, mouthguards can also be employed to improve physical performance. The effects of personalization of mouthguards have rarely been investigated. This 3-armed, randomized, controlled crossover trial investigated the difference of wearing (a) personalized or custom-made (CM, e.g., bite-aligned), (b) standard (BB, boil and bite), and (c) no (CON) mouthguards on general fitness parameters in experienced collegiate football players. A group of 10 upperclassmen (age, 19-22 years; mean ± SD: age = 20.7 ± 0.8 years; body mass = 83 ± 7.4 kg; height = 179.1 ± 5.2 cm; body mass index = 25.9 ± 2.2 kg·cm), National Collegiate Athletic Association Division II football players with at least 2 years of playing experience, were randomly assigned to the 3 mouthguard conditions: a randomized, within-subjects repeated-measures design was applied. All participants were randomly tested on strength and endurance performance V[Combining Dot Above]O2max testing, with Bruce treadmill protocol including (a) time to fatigue, (b) blood lactate concentration in millimoles per liter at stage 2 and (c) at peak fatigue, (d) flexibility, (e) reaction time, (f) squat vertical jump, (g) countermovement vertical jump, and (h) 1 repetition maximum bench press. Repeated-measures analysis of variance showed no significant differences between the 3 conditions for each outcome variable (0.23 < p < 0.94; 0.007 < (Equation is included in full-text article.)< 0.15). These data indicate that CM mouthguards did not superiorly affect general fitness parameters compared with BB and CON. In turn, protective BB or CM mouthpieces did not appear to impair general fitness performance vs. CON. The recommendation of a custom bite-aligning mouthguards for performance enhancement in young Division II football players is questioned. Further studies with larger sample sizes, gender comparison, and (sport) discipline-specific performance testing are needed.


Asunto(s)
Rendimiento Atlético/fisiología , Prueba de Esfuerzo/métodos , Fútbol Americano/fisiología , Protectores Bucales , Estudios Cruzados , Método Doble Ciego , Femenino , Fútbol Americano/lesiones , Humanos , Masculino , Tiempo de Reacción , Adulto Joven
12.
Harefuah ; 155(6): 335-9, 388, 2016 Jun.
Artículo en Hebreo | MEDLINE | ID: mdl-27544983

RESUMEN

PURPOSE: To examine the reliability and validity of a newly developed anaerobic and repeated sprint (RST0 performance capability. METHODS: A total of 35 untrained adolescent schoolchildren (age range 16-18 years) performed four tests: The newly developed 4 x 30 m RST, the Wingate Anaerobic Test (WAnT) and 200 m and 50 m sprint runs. The reliability of the test was assessed by comparing the test and retest performances of the test. The validity of the 4x30m RST was evaluated by computing the relationships among the various indices of the four studied anaerobic tests, and by comparing the effect of a well-defined anaerobic training program on the performance of the four anaerobic tests. RESULTS: Strong and highly significant relationships were found between the mean (MP) and peak (PP) values of the 4x30 m RST (r = 0.88; p < 0.001), and between the MP of the RST and the two short sprints (50m and 200m) (r = 0.81 and 0.94, respectively; p < 0.011. Somewhat weaker, but still significant relationships were observed between the 4x30 RST and the WAnT indices (r's range = 0.56-0.64; p < 0.05). Such relationships suggest that the energetics of all four tests are closely related. Compared with baseline, the training group demonstrated similar and significant improvement in all four anaerobic tests. No such changes were detected for the control group. CONCLUSIONS: The anaerobic system plays a dominant role in the performance of the new 4x30m RST. Furthermore, the new field test is highly reliable and was found to be valid for quantifying gross anaerobic and repeated sprints performance. Therefore, it can be used in pursuing athletes in a wide range of sports, as well as in some relevant occupations.


Asunto(s)
Umbral Anaerobio/fisiología , Rendimiento Atlético/fisiología , Prueba de Esfuerzo , Atletismo/fisiología , Adolescente , Prueba de Esfuerzo/métodos , Prueba de Esfuerzo/normas , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados , Medicina Deportiva/métodos
13.
Eur J Neurol ; 22(12): 1556-63, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26227902

RESUMEN

BACKGROUND AND PURPOSE: Charcot-Marie-Tooth disease (CMT) is a very slowly progressive neuropathy which makes it difficult to detect disease progression over time and to assess intervention efficacy. Experience from completed clinical trials with ascorbic acid and natural history studies confirm difficulties in detecting such changes. Consequently, sensitive-to-change outcome measures (OMs) are urgently needed. METHODS: The relative responsiveness of clinical scales of the Italian-UK ascorbic acid trial (placebo arm) were assessed by using the standardized response mean (SRM), which is the ratio of the paired scores mean change over time to the standard deviation of the score change (0 is worst responsiveness). RESULTS: Little worsening of OM scores was found over 2 years. In detail, the primary OM of the trial, the CMT Neuropathy Score version 1 (CMTNSv1), showed low responsiveness (SRM 0.13). Some CMTNS items showed slightly greater responsiveness (CMT Examination Score 0.17; CMTNS Signs 0.19). Myometric assessments of handgrip and foot dorsiflexion strength were the most responsive (SRM -0.31 and -0.38, respectively). Amongst the other measures, the nine-hole peg test, which assesses upper limb functioning, showed the best sensitivity to change (SRM 0.28). CONCLUSIONS: Overall these OMs showed low or negligible responsiveness, confirming the need to improve current OMs and to develop novel ones for prognostic and interventional studies. However, handgrip and foot dorsiflexion myometry are worth retaining for future trials as they were the most responsive and are likely to be clinically relevant for patients.


Asunto(s)
Enfermedad de Charcot-Marie-Tooth/diagnóstico , Prueba de Esfuerzo/métodos , Evaluación de Resultado en la Atención de Salud/métodos , Adulto , Enfermedad de Charcot-Marie-Tooth/tratamiento farmacológico , Ensayos Clínicos como Asunto , Prueba de Esfuerzo/normas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud/normas
14.
BMC Pregnancy Childbirth ; 15: 45, 2015 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-25886031

RESUMEN

BACKGROUND: Facial coverings (e.g., balaclavas, niqabs, medical/surgical masks, respirators, etc.), that impose low levels of airflow resistive loads, are worn by millions of pregnant women worldwide, but little data exist addressing their impact on pregnancy-associated cardiovascular and pulmonary responses. METHODS: 16 pregnant and 16 non-pregnant women were monitored physiologically (heart rate, blood pressure, mean arterial pressure, total peripheral resistance, stroke volume, cardiac output, oxygen saturation, transcutaneous carbon dioxide, fetal heart rate) and subjectively (exertion) for 1 h of mixed sedentary postural activity (sitting, standing) and moderate exercise (bicycle ergometer) with and without wearing N95 filtering facepiece respirators with filter resistive loads of 94.1 Pa (9.6 mm H2O) - 119.6 Pa (12.2 mm H2O) pressure. RESULTS: The external airflow resistive loads were associated with increases in diastolic pressure (p = 0.004), mean arterial pressure (p = 0.01), and subjective exertion score (p < 0.001) of all study subjects. No significant differences were noted with the external resistive loads between the pregnant and non-pregnant groups for any cardiovascular, pulmonary and subjective variable over 1 h. CONCLUSIONS: Low external airflow resistive loads, during combined sedentary postural activity and moderate exercise over 1 h, were associated with increases in the diastolic and mean arterial pressures of all study subjects, but pregnancy itself was not associated with any significant differences in physiologic or subjective responses to the external airway resistive loads utilized in the study.


Asunto(s)
Fenómenos Fisiológicos Cardiovasculares , Protectores Bucales , Fenómenos Fisiológicos Respiratorios , Adulto , Resistencia de las Vías Respiratorias , Presión Sanguínea/fisiología , Prueba de Esfuerzo/métodos , Femenino , Voluntarios Sanos , Frecuencia Cardíaca/fisiología , Humanos , Monitoreo Fisiológico/métodos , Protectores Bucales/efectos adversos , Protectores Bucales/clasificación , Consumo de Oxígeno , Embarazo , Mecánica Respiratoria
15.
Br J Sports Med ; 49(10): 642-8, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25497489

RESUMEN

OBJECTIVE: To review the measurement properties of physical performance tests (PPTs) of the knee as each pertain to athletes, and to determine the relationship between PPTs and injury in athletes age 12 years to adult. METHODS: A search strategy was constructed by combining the terms 'lower extremity' and synonyms for 'performance test', and names of performance tests with variants of the term 'athlete'. In this, part 1, we report on findings in the knee. The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines were followed and the Consensus-based Standards for the selection of health Measurement Instruments (COSMIN) checklist was used to critique the methodological quality of each paper. A second measure was used to analyse the quality of the measurement properties of each test. RESULTS: In the final analysis, we found 29 articles pertinent to the knee detailing 19 PPTs, of which six were compiled in a best evidence synthesis. The six tests were: one leg hop for distance (single and triple hop), 6 m timed hop, crossover hop for distance, triple jump and single leg vertical jump. The one leg hop for distance is the most often studied PPT. There is conflicting evidence regarding the validity of the hop and moderate evidence that the hop test is responsive to changes during rehabilitation. No test has established reliability or measurement error as assessed by the minimal important change or smallest detectable change. No test predicts knee injury in athletes. CONCLUSIONS: Despite numerous published articles addressing PPTs at the knee, there is predominantly limited and conflicting evidence regarding the reliability, agreement, construct validity, criterion validity and responsiveness of commonly used PPTs. There is a great opportunity for further study of these tests and the measurement properties of each in athletes.


Asunto(s)
Traumatismos en Atletas/fisiopatología , Rendimiento Atlético/fisiología , Prueba de Esfuerzo/métodos , Traumatismos de la Rodilla/fisiopatología , Medicina Deportiva/métodos , Adolescente , Adulto , Anciano , Niño , Prueba de Esfuerzo/normas , Humanos , Articulación de la Rodilla/fisiología , Persona de Mediana Edad , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Medicina Deportiva/normas , Adulto Joven
16.
Br J Sports Med ; 49(10): 649-56, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25614536

RESUMEN

OBJECTIVE: To review the quality of literature and measurement properties of physical performance tests (PPTs) of the lower extremity in athletes. METHODS: Using the PICOS method we established our research question as to whether individual PPTs of the lower extremity have any relationship to injury in competitive athletes ages 12 years to adult (no limit). A search strategy was constructed by combining the terms 'lower extremity' and synonyms for 'performance test' and names of performance tests with variants of the term 'athlete'. After examining the knee in part 1 of this 2 part series, the current report focuses on findings in the rest of the lower extremity. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed and the Consensus-based Standards for the selection of health Measurement Instruments (COSMIN) checklist was used to critique the methodological quality of each paper. A second measure was used to analyse the quality of the measurement properties of each test. RESULTS: Thirty-one articles examined the measurement properties of 14 PPTs pertaining to the lower extremity. The terminology used to name and describe the tests and methodology by which the tests were conducted was inconsistent. The star excursion balance test performed in three directions (anterior, posteromedial, and posterolateral) appears to be the only test to be associated with increased injury risk. There is moderate evidence that the one leg hop for distance and the hexagon hop can distinguish between normal and unstable ankles. There is also moderate evidence that the medial hop can distinguish between painful and normal hips in dancers. CONCLUSIONS: Currently, there is relatively limited research-backed information on PPTs of the lower extremity in athletes. We would suggest convening an international consortium comprised of experts in sports to standardise the descriptions and methodologies, and to set forth a research agenda to establish definitively the measurement properties of the most common PPTs.


Asunto(s)
Traumatismos en Atletas/fisiopatología , Rendimiento Atlético/fisiología , Prueba de Esfuerzo/métodos , Extremidad Inferior/lesiones , Equilibrio Postural/fisiología , Medicina Deportiva/métodos , Adolescente , Adulto , Anciano , Traumatismos del Tobillo/fisiopatología , Niño , Prueba de Esfuerzo/normas , Femenino , Traumatismos de los Pies/fisiopatología , Lesiones de la Cadera/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Medicina Deportiva/normas , Muslo/lesiones , Muslo/fisiología , Adulto Joven
17.
Arch Phys Med Rehabil ; 95(5): 867-74, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24055575

RESUMEN

OBJECTIVE: To assess the jaw-opening force test (JOFT) for dysphagia screening. DESIGN: Criterion standard. SETTING: University dental hospital. PARTICIPANTS: Patients complaining of dysphagia (N=95) and with symptoms of dysphagia with chronic underlying causes (mean age ± SD, 79.3±9.61y; range, 50-94y; men: n=49; mean age ± SD, 77.03±9.81y; range, 50-94y; women: n=46; mean age ± SD, 75.42±9.73y; range, 51-93y) admitted for treatment between May 2011 and December 2012 were included. INTERVENTIONS: None. MAIN OUTCOME MEASURES: All patients were administered the JOFT and underwent fiberoptic endoscopic evaluation of swallowing (FEES). The mean jaw-opening strength was compared with aspiration (ASP) and pharyngeal residue observations of the FEES, which was used as the criterion standard. RESULTS: A receiver operating characteristic (ROC) curve analysis was performed. Forces of ≤3.2kg for men and ≤4kg for women were appropriate cutoff values for predicting ASP with a sensitivity and specificity of .57 and .79 for men and .93 and .52 for women, respectively. Based on the ROC analyses for predicting pharyngeal residue, forces of ≤5.3kg in men and ≤3.9kg in women were appropriate cutoff values, with a sensitivity and specificity of .80 and .88 for men and .83 and .81 for women, respectively. CONCLUSIONS: The JOFT could be a useful screening tool for predicting pharyngeal residue and could provide useful information to aid in the referral of patients for further diagnostic imaging testing. However, given its low sensitivity to ASP the JOFT should be paired with other screening tests that predict ASP.


Asunto(s)
Trastornos de Deglución/diagnóstico , Deglución/fisiología , Prueba de Esfuerzo/métodos , Terapia por Ejercicio/métodos , Maxilares/fisiopatología , Tamizaje Masivo/métodos , Anciano , Anciano de 80 o más Años , Trastornos de Deglución/fisiopatología , Trastornos de Deglución/rehabilitación , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Curva ROC , Reproducibilidad de los Resultados
18.
Br J Sports Med ; 48 Suppl 1: i22-31, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24668375

RESUMEN

In tennis, sport-specific technical skills are predominant factors, although a complex profile of physical performance factors is also required. The fitness test batteries assist in examining tennis players' capabilities for performance at different levels in the laboratory as well as in the field, in the junior or elite level. While laboratory tests can be, and are, used to evaluate basic performance characteristics of athletes in most individual sports, in a more specific approach, field-based methods are better suited to the demands of complex intermittent sports like tennis. A regular test battery performed at different periods of the year allows to obtain an individual's performance profile, as well as the ability to prescribe individual training interventions. Thus, the aim of the present review was to describe and evaluate the different physical tests recommended and used by practitioners, sports scientists and institutions (national tennis federations).


Asunto(s)
Aptitud Física/fisiología , Tenis/fisiología , Ejercicio Físico/fisiología , Prueba de Esfuerzo/métodos , Humanos , Destreza Motora/fisiología , Fuerza Muscular/fisiología , Músculo Esquelético/fisiología , Resistencia Física/fisiología , Medicina Deportiva/métodos
19.
J Strength Cond Res ; 28(4): 950-7, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24077371

RESUMEN

This study investigated the effect of restricting nasal breathing during a series of 20-m shuttle runs. Ten male participants (mean age = 21.7 ± 2.4 years, height = 1.80 ± 0.62 m, mass = 79.2 ± 10.4 kg, sum of 4 skinfolds = 54.5 ± 7.8 mm) were required to either (a) dive on the ground and complete a rolling sequence (condition = GRD) or (b) complete the shuttles while staying on their feet and tagging the line with 1 foot, at the end of each 20-m segment (condition = STD). The shuttle runs were completed with and without a nose clip (no clip = nc; with a clip = clip) under 4 different trial conditions in a randomized order (GRDnc; GRDclip; STDnc; and STDclip), requiring the participants to return on 4 separate occasions separated by 5-7 days. Heart rate was recorded throughout each trial, and the rate of perceived exertion (RPE) was measured at the completion of each shuttle sequence. Pretrial and posttrial lactate and respiratory function measures were also recorded. The general linear model with repeated measures analysis indicated that there was a significant effect for Roll (GRD > STD) (p ≤ 0.05) but not for Clip (p > 0.05) on total time to completion in the trials. There was no significant interaction of the conditions (Roll × Clip) for RPE (p > 0.05). Similarly, there was no significant effect for blood lactate measured 3 minutes post the last shuttle for Roll (p > 0.05) and Clip (p > 0.05). There was a significant main effect on the HR across all 6 time points (i.e., pre, intervals 1-4 and 10 minutes post) (p ≤ 0.05) and for Roll (GRD > STD) (p ≤ 0.05), but not for Clip (p > 0.05). No significant effect of Roll or Clip was found for any of the recorded ventilation measures (p > 0.05). On the basis of these findings, the use of restricted nasal breathing, while performing a high-intensity shuttle sequence as a method of increasing the acute training effect on athletes, is questionable, so strength and conditioning coaches should carefully consider their rationale for using such a training strategy.


Asunto(s)
Prueba de Esfuerzo/métodos , Frecuencia Cardíaca/fisiología , Lactatos/sangre , Respiración por la Boca , Esfuerzo Físico/fisiología , Carrera/fisiología , Aceleración , Atletas , Metabolismo Energético/fisiología , Volumen Espiratorio Forzado/fisiología , Humanos , Masculino , Consumo de Oxígeno/fisiología , Valores de Referencia , Muestreo , Volumen de Ventilación Pulmonar , Atletismo , Capacidad Vital , Adulto Joven
20.
Chron Respir Dis ; 10(1): 5-10, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23149383

RESUMEN

Pursed lips breathing (PLB) is used by a proportion of patients with chronic obstructive pulmonary disease (COPD) to alleviate dyspnea. It is also commonly used in pulmonary rehabilitation. Data to support its use in patients who do not spontaneously adopt PLB are limited. We performed this study to assess the acute effects of PLB on exercise capacity in nonspontaneously PLB patients with stable COPD. We performed a randomized crossover study comparing 6-min walk test (6MWT) at baseline without PLB with 6WMT using volitional PLB. Spirometry, maximal inspiratory and expiratory mouth pressures, and diaphragmatic excursion during tidal and vital capacity breathing using B-mode ultrasonography were measured at baseline and after 10 min of PLB. A Visual Analog Scale (VAS) assessed subjective breathlessness at rest, after 6MWT and after 6MWT with PLB. p ≤ 0.01 was considered significant. Mean ± SD age of patients was 53.1 ± 7.4 years. Forced expiratory volume in 1 second was 1.1 ± 0.4 L/min (38.4 ± 13.2% predicted). Compared with spontaneous breathing, all but one patient with PLB showed a significant increment in 6MW distance (+34.9 ± 26.4 m; p = 0.002). There was a significant reduction in respiratory rate post 6MWT with PLB compared with spontaneous breathing (-4.4 ± 2.8 per minute; p = 0.003). There was no difference in VAS scores. There was a significant correlation between improvement in 6MWT distance and increase in diaphragmatic excursion during forced breathing. The improvement was greater in patients who had poorer baseline exercise performance. PLB has an acute benefit on exercise capacity. Sustained PLB or short bursts of PLB may improve exercise capacity in stable COPD.


Asunto(s)
Ejercicios Respiratorios , Disnea , Prueba de Esfuerzo/métodos , Tolerancia al Ejercicio , Femenino , Humanos , Masculino , Persona de Mediana Edad , Monitoreo Fisiológico/métodos , Aptitud Física , Modalidades de Fisioterapia , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Enfermedad Pulmonar Obstructiva Crónica/terapia , Pruebas de Función Respiratoria/métodos , Mecánica Respiratoria , Índice de Severidad de la Enfermedad , Estadística como Asunto , Resultado del Tratamiento
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