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1.
Artículo en Inglés | MEDLINE | ID: mdl-36141834

RESUMEN

Populations with potential damage to somatosensory, vestibular, and visual systems or poor motor control are often studied during gait initiation. Aquatic activity has shown to benefit the functional capacity of incomplete spinal cord injury (iSCI) patients. The present study aimed to evaluate gait initiation in iSCI patients using an easy-to-use protocol employing four wearable inertial sensors. Temporal and acceleration-based anticipatory postural adjustment measures were computed and compared between dry-land and water immersion conditions in 10 iSCI patients. In the aquatic condition, an increased first step duration (median value of 1.44 s vs. 0.70 s in dry-land conditions) and decreased root mean squared accelerations for the upper trunk (0.39 m/s2 vs. 0.72 m/s2 in dry-land conditions) and lower trunk (0.41 m/s2 vs. 0.85 m/s2 in dry-land conditions) were found in the medio-lateral and antero-posterior direction, respectively. The estimation of these parameters, routinely during a therapy session, can provide important information regarding different control strategies adopted in different environments.


Asunto(s)
Equilibrio Postural , Traumatismos de la Médula Espinal , Terapia Acuática , Marcha , Humanos , Agua
2.
Artículo en Inglés | MEDLINE | ID: mdl-34063665

RESUMEN

The purpose of the present investigation was to compare the acute responses on muscle architecture, electromechanical delay (EMD) and performance following a high volume (HV: 5 sets of 10 reps at 70% of 1 repetition maximum (1RM)) and a high intensity (HI: 5 sets of 3 reps at 90% of 1RM) bench press protocol in women. Eleven recreationally trained women (age = 23.3 ± 1.8 y; body weight = 59.7 ± 6.0 kg; height = 164.0 ± 6.3 cm) performed each protocol in a counterbalanced randomized order. Muscle thickness of pectoral (PEC MT) and triceps muscles (TR MT) were collected prior to and 15 min post each trial. In addition, EMD of pectoral (PEC EMD) and triceps (TR EMD) muscles were calculated during isometric bench press maximum force tests performed at the same timepoints (IBPF). Significantly greater increases in PEC MT (p < 0.001) and TR MT (p < 0.001) were detected following HV compared to HI. PEC EMD showed a significantly greater increase following HV compared to HI (p = 0.039). Results of the present study indicate that the HV bench press protocol results in greater acute morphological and neuromuscular changes compared to a HI protocol in women. Evaluations of muscle morphology and electromechanical delay appear more sensitive to fatigue than maximum isometric force assessments.


Asunto(s)
Entrenamiento de Fuerza , Adulto , Brazo , Peso Corporal , Terapia por Ejercicio , Femenino , Humanos , Fuerza Muscular , Músculo Esquelético , Adulto Joven
3.
J Strength Cond Res ; 35(Suppl 1): S180-S187, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-30844990

RESUMEN

ABSTRACT: Bartolomei, S, Totti, V, Griggio, F, Malerba, C, Ciacci, S, Semprini, G, and Di Michele, R. Upper-body resistance exercise reduces time to recover after a high-volume bench press protocol in resistance-trained men. J Strength Cond Res 35(2S): S180-S187, 2021-The aim of this study was to compare the effects of active and passive strategies on the recovery response after a high-volume bench press protocol. Twenty-five resistance-trained men (mean ± SD: age = 25.8 ± 3.6 years; body mass = 87.1 ± 12.1 kg; and height = 177.4 ± 4.9 cm) performed a high-volume bench press session (8 sets of 10 reps at 70% of 1 repetition maximum). Subsequently, they were randomly assigned to an active recovery (AR) group (n = 11) or to a passive recovery (PR) group (n = 14). Active recovery consisted of light bench press sessions performed 6 hours and 30 hours after the high-volume exercise protocol. Muscle performance (bench throw power [BTP] and isometric bench press [IBP]) and morphology (muscle thickness of pectoralis major [PECMT] and of triceps brachii [TRMT]) were measured before exercise (baseline [BL]), and at 15-minute (15P), 24-hour (24P), and 48-hour (48P) post-exercise. Post-exercise recovery of both maximal strength and power was accelerated in AR compared with PR. Both BTP and IBP were significantly (p < 0.001) reduced at 15P and 24P in PR, whereas changes were significant (p < 0.001) at 15P only in AR. PECMT was still significantly (p = 0.015) altered from BL at 48P in PR, whereas changes were significant (p < 0.001) at 15P only in AR. No significant interactions (p > 0.05) between PR and AR were detected for TRMT and muscle soreness. The present results indicate that AR enhances the recovery rate after high-volume exercise sessions and may be included in resistance training programs to optimize muscle adaptations.


Asunto(s)
Entrenamiento de Fuerza , Adulto , Ejercicio Físico , Humanos , Masculino , Fuerza Muscular , Músculo Esquelético , Levantamiento de Peso , Adulto Joven
4.
J Hum Kinet ; 68: 59-67, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31531133

RESUMEN

The purpose of this study was to compare the physiological responses of a single bout of an eccentric accentuated bench press protocol (120% of 1RM in the eccentric phase/80% in the concentric phase; [120/80]) versus a regular high-intensity exercise protocol (80%/80%; [80/80]) in resistance-trained men. Eleven men (age = 25.6 ± 3.9 y; body mass = 84.6 ± 11.2 kg; body height = 176.4 ± 3.9 cm) with 6.3 ± 3.4 y of resistance training experience performed each protocol in counterbalanced, randomized order. Isometric, isokinetic and ballistic tests were performed at the bench press (IBPF, ISOK and BTP, respectively) at baseline (BL), 15-min (15P), 24-h (24P), and 48-h (48P) post-exercise for each testing session. In addition, muscle thickness of the pectoralis major (PecMT) was measured at the same timepoints via ultrasound. Significantly greater reductions in BTP (p < 0.001), peak force during both ISOK (p = 0.005) and IBPF (p = 0.006) at 15P were detected in 120/80 compared to 80/80. BTP was still significantly (p = 0.009) impaired at 48P following the 120/80 protocol, while no differences were noted following 80/80. PecMt was significantly elevated following both 120/80 and 80/80 (p < 0.05) at 15P, but significant differences between the trials were present at 15P and 24P (p = 0.005 and p = 0.008, respectively). Results indicated that heavy eccentric loading during the bench press exercise caused greater performance deficits than a bout of traditionally loaded high intensity resistance exercise. Power performance appears to be more influenced by the 120/80 protocol than isometric peak force. Eccentrically loaded exercise sessions should be separated by at least 48 hours to obtain a complete recovery of the initial muscle morphology and performance.

5.
J Strength Cond Res ; 33(11): 3123-3128, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29470363

RESUMEN

Bartolomei, S, Nigro, F, Gubellini, L, Ciacci, S, Merni, F, Treno, F, Cortesi, M, and Semprini, G. Physiological and sport-specific comparison between Division I and Division II Italian male field hockey players. J Strength Cond Res 33(11): 3123-3128, 2019-The purpose of this study was to compare the anthropometric and performance profiles of Division I (D1) and Division II (D2) Italian field hockey players. Fifteen DI players and 15 D2 players (age = 25.4 ± 5.2 years; body mass = 78.5 ± 9.0 kg; and body height = 179.6 ± 7.8 cm) were assessed on one occasion for anthropometry, body composition, physiological measurements, and sport-specific skills. Differences between the 2 groups were evaluated using a 1-way analysis of variance. Pearson correlations were used to examine relationships between the different measurements. Significantly (p = 0.039) lower percentages of body fat were found on D1 group compared with D2 group (-3.5%). A significant difference between the groups were noted for shooting accuracy (p = 0.013), with the D1 group performing 14.5% better than the DII group. No significant differences between the groups were found for shooting speed (p = 0.103) and slalom and dribbling performances (p = 0.292 and p = 0.416, respectively). Physiological assessments did not show any significant differences between the groups. Large correlations (r = 0.73; p < 0.001) were found between shooting speed and accuracy. Moderate correlations were observed between the shooting speed and the hand grip strength, in particular of the left hand (r = 0.61; p = 0.007). Results of this study indicate that the difference between D1 and D2 players may be more related to technical factors than to physical fitness. Ball control, however, may not be a limiting factor in D2 players.


Asunto(s)
Aptitud , Rendimiento Atlético , Hockey/fisiología , Aptitud Física/fisiología , Adulto , Composición Corporal , Estatura , Fuerza de la Mano , Humanos , Italia , Masculino , Adulto Joven
6.
J Strength Cond Res ; 32(6): 1503-1510, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29528954

RESUMEN

Bartolomei, S, Nigro, F, Ruggeri, S, Malagoli Lanzoni, I, Ciacci, S, Merni, F, Sadres, E, Hoffman, JR, and Semprini, G. Comparison between bench press throw and ballistic push-up tests to assess upper-body power in trained individuals. J Strength Cond Res 32(6): 1503-1510, 2018-The purpose of this study was to validate the ballistic push-up (BPU) test performed with hands on a force plate as a method to measure upper-body power. Twenty-eight experienced resistance-trained men (age = 25.4 ± 5.2 years; body mass = 78.5 ± 9.0 kg; body height = 179.6 ± 7.8 cm) performed, 2 days apart, a bench press 1 repetition maximum (1RM) test and upper-body power tests. Mean power (MP) and peak power (PP) were assessed using the bench press throw (BT) test and the BPU test performed in randomized order. The area under the force/power curve (AUC) obtained at BT was also calculated. Power expressed at BPU was estimated using a time-based prediction equation. Mean force and the participant's body weight were used to predict the bench press 1RM. Pearson product-moment correlations were used to examine relationships between the power assessment methods and between the predicted 1RM bench and the actual value. Large correlations (0.79; p < 0.001) were found between AUC and MP expressed at BPU. Large correlations were also detected between MP and PP expressed at BT and BPU (0.75; p < 0.001 and 0.74; p < 0.001, respectively). Very large correlations (0.87; p < 0.001) were found between the 1RM bench and the 1RM predicted by the BPU. Results of this study indicate that BPU represents a valid and reliable method to estimate the upper-body power in resistance-trained individuals.


Asunto(s)
Prueba de Esfuerzo/métodos , Fuerza Muscular , Entrenamiento de Fuerza , Levantamiento de Peso/fisiología , Adulto , Área Bajo la Curva , Humanos , Masculino , Músculo Esquelético/fisiología , Distribución Aleatoria , Adulto Joven
7.
J Strength Cond Res ; 32(1): 244-247, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28922211

RESUMEN

Bartolomei, S, Nigro, F, Luca, G, Gabriele, S, Ciacci, S, Hoffman, JR, and Merni, F. Acute effects of ammonia inhalants on strength and power performance in trained men. J Strength Cond Res 32(1): 244-247, 2018-The aim of the present study was to investigate the influence of ammonia inhalants on lower body power and maximal isometric strength in trained men. Twenty experienced resistance trained men (age = 26.7 ± 3.7 years; body weight = 80.59 ± 9.0 kg; body height = 179.5 ± 5.7 cm) were tested for counter movement jump power (CMJP), maximal force, and peak rate of force development (pRFD20) expressed during an isometric midthigh pull (IMTP). Assessments were performed using either an ammonia inhalant (AI), a placebo (PL), or no inhalants (N). One-way analysis of variance (ANOVA) with repeated measures was used to compare strength and power performance between the different trials. A significant (p < 0.01) increase in pRFD20 was detected following the use of AI. No significant effects of trial were noted for CMJP and IMTP maximal force (p = 0.251 and p = 0.075, respectively). Results of the present study showed a potential ergogenic effect of AI on rate of force development (i.e., explosive force output), with a trend toward an improvement in maximal force production. The mechanism of action may be related to the stimulatory action of AI often reported by athletes as a "psyching-up" effect. The positive effect of AI on the rate of force development may represent an advantage in sports requiring high rates of force production.


Asunto(s)
Amoníaco/administración & dosificación , Estimulantes del Sistema Nervioso Central/administración & dosificación , Fuerza Muscular/fisiología , Músculo Esquelético/fisiología , Adulto , Atletas , Estudios Cruzados , Humanos , Contracción Isométrica/fisiología , Masculino , Movimiento , Entrenamiento de Fuerza , Adulto Joven
8.
J Sports Med Phys Fitness ; 58(10): 1375-1382, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28597614

RESUMEN

BACKGROUND: The aim of this study was to compare the effects of two different training programs oriented to improve vertical jump performance and leg stiffness in basketball players. METHODS: Fifty-eight male basketball players were involved, divided into three age groups (senior, U19 and U17). Subsequently, within any age group, the players were randomLy divided into two training groups, respectively performing a 16-week "hang-clean" training program (HCL), and a "half-squat" training program (HSQ), lasting for the same duration. HCL was based on the hang clean exercise and included also jump rope training; HSQ was based on the half squat exercise and included also speed ladder training. The squat jump (SJ), the countermovement jump without and with arm swing, and with one step approach (respectively, CMJ, CMJS, and TCMJS) and explosive strength indices obtained with a leg stiffness test were assessed pre- and post-training. RESULTS: In senior and U19 athletes both training programs involved an improvement of Vertical Jump performance, with some differences between different age groups. Instead, for the U17 players, only the HSQ led to an enhancement of SJ and TCMJS. Significant enhancement of leg stiffness was observed only in U19 and U17 groups after training. CONCLUSIONS: The present study showed that the programs based on the hang-clean and half squat allowed to improve explosive strength in basketball training. However, only HSQ was effective for the U17 group. Thus, the present findings demonstrate that specific training programs should be designed according to the age of the players.


Asunto(s)
Rendimiento Atlético , Baloncesto , Entrenamiento de Fuerza/métodos , Adolescente , Adulto , Atletas , Ejercicio Físico , Prueba de Esfuerzo , Humanos , Estudios Longitudinales , Masculino , Fuerza Muscular , Adulto Joven
9.
J Sports Sci ; 35(13): 1270-1278, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27540875

RESUMEN

The start kinematics has been reported to differ between male and female sprinters. This study aimed to determine whether kinematic differences between the sexes are attributable to an effect of sex per se, or rather to the absolute performance level of the sprinters, quantified by the 100-m time. A total of 20 sprinters (10 M, 10 F), including world-class and elite athletes, were assessed. Start phases from the "set" position to the first two steps were analysed. Linear regression analyses showed a few significant differences between sexes when taking into account the effect of performance level: M had shorter pushing phase duration, higher horizontal velocity at block clearing, and shorter contact times of the first two steps. Conversely, the performance level affected most of the examined parameters: faster sprinters showed the centre of mass (CM) closer to the ground and a more flexed front knee in the "set" position, longer pushing phase duration, lower vertical velocity of the CM at block clearing, and longer contact times and shorter flight times in the first two steps. These findings suggest that the start kinematics is only partially affected by the sex of sprinters, whereas a bigger role is played by their performance level.


Asunto(s)
Rendimiento Atlético/fisiología , Conducta Competitiva/fisiología , Carrera/fisiología , Atletismo/fisiología , Aceleración , Adolescente , Adulto , Fenómenos Biomecánicos , Femenino , Humanos , Modelos Lineales , Masculino , Factores Sexuales , Estudios de Tiempo y Movimiento , Adulto Joven
10.
Gait Posture ; 31(2): 209-12, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19926284

RESUMEN

The contact time (CT) and the ratio between the duration of braking (BP) and propulsion phase (PP) during the support are two mechanical parameters that are relevant for the performance in sprinting. Several different kinematic methods have been used to estimate the BP-PP transition point, with some disagreements among studies. The purpose of this study was to compare three criteria to individuate that point: the maximum knee flexion (KNEEFLEX), the maximum fall of the COM (COMVERT) and the horizontal COM acceleration (COMHORIZ). It was hypothesized that these three events would take place in different instants, representing different moments of the step cycle. The kinematic analysis was performed through stereophotogrammetry on seven male middle-level sprinters (mean + or - SD height: 180 + or - 5 cm; body mass: 75 + or - 11 kg; personal best on 100 m: 10.96 + or - 0.45 s). The COMVERT expressed as percentage of CT (mean + or - SD 31.73 + or - 8.29%) was on average strongly anticipated compared to both KNEEFLEX (45.07 + or -3.60%, p < 0.01) and COMHORIZ (56.86 + or - 8.56%, p < 0.01). The approximately 12% difference between KNEEFLEX and COMHORIZ was also statistically significant (p < 0.01). The 40-60% relative proportion of BP and PP considered to be optimal in the literature, was reflected in this study only by the KNEEFLEX criterion. Given the importance of BP time as a reference parameter to assess the training status and efficacy of training interventions, it looks necessary both from a scientific and applied perspective to consider a standardized criterion to identify the BP-PP transition point.


Asunto(s)
Carrera/fisiología , Aceleración , Análisis de Varianza , Rendimiento Atlético , Fenómenos Biomecánicos , Humanos , Imagenología Tridimensional/instrumentación , Articulación de la Rodilla/fisiología , Masculino , Estadísticas no Paramétricas
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