Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Resultados 1 - 20 de 60
Filtrar
1.
J Musculoskelet Neuronal Interact ; 22(1): 62-69, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35234160

RESUMEN

OBJECTIVES: The purpose of this study was to determine the effects of short-term lumbopelvic stability training on muscular endurance and stability in elite female cyclists. METHODS: Twenty-four female road cyclists were randomly allocated to a core training group (CTG, n=12) or control group (CG, n=12). In addition to their scheduled training the CTG performed a core training program, that consisted of 6 core exercises performed in a session every other day until a total of 8 training sessions were completed. The CG did not receive the core training program and completed their scheduled training. The lumbopelvic-hip complex was assessed pre- and post-core program included the following exercises: single leg deadlift (SLD), bird-dog (BD), plank test (PT), and side-bridge plank test (SPT). RESULTS: In comparison to CG, CTG significantly improved the time to failure in PT, SPT-Left, and SPT-Right (p<0.05). Further, CTG resulted in a significant decrease in SLD (p<0.05) compared to CG for the three accelerometry measures. CONCLUSION: The present results indicate that following 8 sessions of lumbopelvic stability training muscular endurance and core stability were enhanced.


Asunto(s)
Ciclismo , Prueba de Esfuerzo , Terapia por Ejercicio , Estabilidad Central , Terapia por Ejercicio/métodos , Femenino , Humanos
2.
J Strength Cond Res ; 36(7): 1930-1935, 2022 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-32732776

RESUMEN

ABSTRACT: Soriano, MA, García-Ramos, A, Calderbank, J, Marín, PJ, Sainz de Baranda, P, and Comfort, P. Does sex impact the differences and relationships in the one repetition maximum performance across weightlifting overhead pressing exercises? J Strength Cond 36(7): 1930-1935, 2022-This study aimed to determine the impact of sex on the differences and relationships of the one repetition maximum (1RM) performance between 3 overhead pressing exercises (push press [PP], push jerk [PJ] and split jerk [SJ]). 15 men (body mass [BM]: 82.3 ± 9.9 kg; weightlifting training experience: 2.6 ± 1.6 years) and 15 women (BM: 64.4 ± 7.0 kg; weightlifting training experience: 2.2 ± 1.4 years) participated in this study. A ratio-scaled (1RM·BM-1) was used for the comparison between them. The 1RM of the 3 exercises were evaluated within the same testing session using a combined 1RM assessment method. The interaction effect of exercise and sex did not reach statistical significance (p = 0.671; η2 = 0.001). In contrast, there were significant main effects of exercise (p ≤ 0.01) and sex (p < 0.001) with medium (η2 = 0.096) and large effect sizes (η2 = 0.306), respectively. A similar main effect of exercise was reported for both men (PP [1.0 ± 0.1 kg·kg-1] < PJ [1.1 ± 0.2 kg·kg-1] ∼ SJ [1.2 ± 0.2 kg·kg-1]) and women (PP [0.8 ± 0.1 kg·kg-1] < PJ [0.9 ± 0.2 kg·kg-1] ∼ SJ [0.9 ± 0.2 kg·kg-1]). The 1RM performance of the 3 exercises was significantly correlated for men (r [range] = 0.856-0.963) and women (r [range] = 0.636-0.925). Sex does not affect the differences in the 1RM performance across weightlifting overhead pressing exercises. However, stronger correlations and lower variation in the 1RM performance during the PP, PJ, and SJ are expected for men compared with women.


Asunto(s)
Fuerza Muscular , Entrenamiento de Fuerza , Ejercicio Físico , Femenino , Humanos , Masculino , Músculo Esquelético , Entrenamiento de Fuerza/métodos , Levantamiento de Peso
3.
J Musculoskelet Neuronal Interact ; 21(1): 59-67, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33657755

RESUMEN

OBJECTIVES: The purpose of the current study was to firstly examine the effects of different whole-body vibration (WBV) frequencies in the lower-body muscles when applied simultaneously during a bridge exercise. Secondly, determine if there were any sex differences in the lower-body muscles of WBV during the bridge. METHODS: Seven females and 7 males completed 2 familiarization and 1 test sessions. In the test session participants were randomized to complete one 30 s bout of a bridge exercise for 3 separate conditions followed by 3-min of rest. The 3 conditions (a) No-WBV (without WBV); (b) WBV-30 (30 Hz, low amplitude); (c) WBV-50 (50 Hz, low amplitude) were performed on a WBV platform. Muscle activity of the biceps femoris (BF), semitendinosus (ST), gluteus maximus (Gmax), multifidus muscle (MF) muscles were measured. RESULTS: Muscle activity was increased with WBV in the BF and ST muscles at WBV-30 and WBV-50 conditions (p<0.05) vs. no-WBV. During No-WBV and WBV-50 conditions, males had a higher biceps femoris activity compared to females for (p<0.05) 45 and 27 %, respectively; however, during all conditions females had a high level of Gmax activity (57%) than males (p<0.05). CONCLUSION: Additional vibration at 30 and 50 Hz during the bridge exercise could be a useful method to enhance hamstring muscle activity.


Asunto(s)
Electromiografía/métodos , Músculo Esquelético/fisiología , Posición Supina/fisiología , Vibración/uso terapéutico , Adulto , Femenino , Humanos , Masculino , Distribución Aleatoria , Adulto Joven
4.
J Musculoskelet Neuronal Interact ; 21(4): 475-480, 2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-34854386

RESUMEN

OBJECTIVES: The purpose of the present study is to assess the effects of an intense cycling training session on the stability of the lumbopelvic-hip complex through two dynamic exercise tests - the single-leg-deadlift (SLD) and a variation of the bird-modified dog (BD), via the OCTOcore application. METHODS: Thirty-one elite female road cyclists were self-evaluated with their own smartphones, before and immediately after finishing their training sessions. Right, left and composite were measured for each exercise test. RESULTS: There was a significant time effect on performance for both the SLB and BD tests (p<0.05; η2=0.137), and the SLD and BD tests were increased with respect to the pre-test at 15% and 17%, respectively. CONCLUSION: An intense cycling training session produced significant alterations in lumbopelvic behavior in the elite female cyclists. The OCTOcore application demonstrated that it was a sensitive tool in detecting these changes and it could easily be used by the cyclists themselves.


Asunto(s)
Ciclismo , Prueba de Esfuerzo , Animales , Perros , Femenino
5.
J Strength Cond Res ; 35(11): 2988-2992, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31972827

RESUMEN

ABSTRACT: Soriano, MA, García-Ramos, A, Torres-González, A, Castillo-Palencia, J, Ayuso, V, Marín, PJ, and Comfort, P. Validity and reliability of a standardized protocol for assessing the one repetition maximum performance during overhead pressing exercises. J Strength Cond Res 35(11): 2988-2992, 2021-The aim of this study was to determine the validity of performing 3 one repetition maximum (1RM) assessments for the push press (PP), push jerk (PJ), and split jerk (SJ) in sequence in one testing session vs. the criterion method (testing on separate days), while determining the between-session reliability of the combined assessment. Twenty-two well-trained men (n = 22; age: 28.5 + 1.3 years; height: 1.80 + 0.04 m; body mass: 84.9 + 1.9 kg; training experience: 4.27 + 4.08 years) participated in this study. The 1RM was assessed in a sequential order in the same testing session (combined 1RM assessment) for the PP, PJ, and SJ on 2 occasions, to determine between-session reliability. The 1RM for each exercise was also examined on 3 separate sessions to compare the results against the combined method. A high reliability, low variability, and low measurement error were evident for the PP (intraclass correlation coefficient [ICC] = 0.960; coefficient of variation [CV] = 1.8%; smallest detectable difference [SDD] = 7.1%), PJ (ICC = 0.978; CV = 1.5%; SDD = 5.4%) and SJ (ICC = 0.987; CV = 0.8%; SDD = 4.6%). In addition, there were no significant (p > 0.05) or meaningful (η2 ≤0.001) differences between the single and combined assessments. The high reliability and validity of the combined assessment suggest that practitioners and researchers may simplify the testing procedure by assessing the 1RM during the 3 main overhead pressing exercises in a single testing session.


Asunto(s)
Entrenamiento de Fuerza , Levantamiento de Peso , Adulto , Prueba de Esfuerzo/métodos , Humanos , Masculino , Fuerza Muscular , Reproducibilidad de los Resultados , Entrenamiento de Fuerza/métodos
6.
Sensors (Basel) ; 20(5)2020 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-32110939

RESUMEN

The aim of this study was to evaluate changes in electromyographic activity with the use of gradual compression stockings (GCSs) on middle-distance endurance athletes' performance, based on surface electromyography measurement techniques. Sixteen well-trained athletes were recruited (mean ± SD: age 33.4 ± 6.3 years, VO2max 63.7 ± 6.3 mL·kg-1·min-1, maximal aerobic speed 19.7 ± 1.5 km·h). The athletes were divided into two groups and were assigned in a randomized order to their respective groups according to their experience with the use of GCSs. Initially, a maximum oxygen consumption (VO2max) test was performed to standardize the athletes' running speeds for subsequent tests. Afterward, electromyographic activity, metabolic, and performance variables for each group were measured with surface electromyography. In addition, blood lactate concentration was measured, both with and without GCSs, during 10 min at 3% above VT2 (second ventilatory threshold), all of which were performed on the track. Next, surface electromyography activity was measured during a 1 km run at maximum speed. No significant changes were found in electromyography activity, metabolic and performance variables with GCSs use (p > 0.164) in any of the variables measured. Overall, there were no performance benefits when using compression garments against a control condition.


Asunto(s)
Atletas , Músculos/fisiología , Carrera/fisiología , Medias de Compresión , Adulto , Electromiografía , Femenino , Humanos , Pierna/fisiología , Masculino
7.
J Musculoskelet Neuronal Interact ; 18(2): 262-267, 2018 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-29855449

RESUMEN

INTRODUCTION: Foam roller is a device used as a massage intervention for rehabilitation and fitness performance. OBJECTIVE: To examine the effects on the ankle dorsiflexion mobility of the foam roller as well as the combination of foam roller and vibration applied to the ankle plantarflexors muscles, and to observe the possible cross-effect. METHODS: Thirty-eight undergraduate students participated in the study (19 males and 19 females). This study investigated. Three conditions (3 sets of 20 s) were performed in a randomized order (independent variables): 1) foam roller (Roller), 2) foam roller and vibration (Roller+VIB), and 3) no foam roller or vibration (Control). to determine whether of foam roller with or without vibration would benefit ankle dorsiflexion mobility. Ankle dorsiflexion ROM and plantar flexor were measured in both legs before and immediately after the treatment. RESULTS: A cross-effect was found in the non-stimulated leg. There was a significant effect on ankle mobility of Roller and Roller+VIB conditions (6% and 7%, p<0.001). CONCLUSION: Foam roller massage and vibration stimulus' foam roller massage increase ankle mobility producing a cross-effect.


Asunto(s)
Articulación del Tobillo/fisiología , Masaje , Modalidades de Fisioterapia , Rango del Movimiento Articular/fisiología , Vibración , Adolescente , Adulto , Tobillo , Femenino , Humanos , Masculino , Músculo Esquelético/fisiología , Adulto Joven
8.
J Strength Cond Res ; 31(3): 765-772, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27191690

RESUMEN

Martín-Hernández, J, Ruiz-Aguado, J, Herrero, AJ, Loenneke, JP, Aagaard, P, Cristi-Montero, C, Menéndez, H, and Marín, PJ. Adaptation of perceptual responses to low-load blood flow restriction training. J Strength Cond Res 31(3): 765-772, 2017-The purpose of this study was to determine the adaptive response of ratings of perceived exertion (RPE) and pain over 6 consecutive training sessions. Thirty subjects were assigned to either a blood flow restriction training (BFRT) group or a high-intensity resistance training (HIT) group. Blood flow-restricted training group performed 4 sets (30 + 15 + 15 + 15, respectively) of unilateral leg extension at an intensity of 20% one repetition maximum (1RM) while a restrictive cuff was applied to the most proximal part of the leg. The HIT group performed 3 sets of 8 repetitions with 85% 1RM. Ratings of perceived exertion and pain were assessed immediately after each exercise set along the 6 training sessions and were then averaged to obtain the overall RPE and pain per session. Statistical analyses showed significant main effects for group (p ≤ 0.05) and time (p < 0.001). Ratings of perceived exertion values dropped from session 1 to session 6 in both BFRT (8.12 ± 1.3 to 5.7 ± 1.1, p < 0.001) and HIT (8.5 ± 1.2 to 6.40 ± 1.2, p < 0.001). Similar results were observed regarding pain ratings (BFRT: 8.12 ± 1.3 to 5.90 ± 1.55, p < 0.001; HIT: 6.22 ± 1.7 to 5.14 ± 1.42, p < 0.01). Our results indicate that RPE was higher after HIT, whereas differences did not reach significance regarding pain. These perceptual responses were attenuated over time, and the time course of this adaptive response was similar between BFRT and HIT. In summary, BFRT induces a marked perceptual response to training, comparable with that observed with HIT. However, this response becomes attenuated with continuous practice, leading to moderate values of RPE and pain. Perceptual responses may not limit the application of BFRT to highly motivated individuals.


Asunto(s)
Adaptación Fisiológica/fisiología , Dolor/fisiopatología , Percepción/fisiología , Flujo Sanguíneo Regional/fisiología , Entrenamiento de Fuerza/métodos , Adulto , Hemodinámica , Humanos , Pierna , Masculino , Esfuerzo Físico/fisiología , Adulto Joven
9.
J Phys Ther Sci ; 29(8): 1363-1367, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28878463

RESUMEN

[Purpose] This study assessed the relationships between the ankle dorsiflexion range of motion and foot and ankle strength. [Subjects and Methods] Twenty-nine healthy (young adults) volunteers participated in this study. Each participant completed tests for ankle dorsiflexion range of motion, hallux flexor strength, and ankle plantar and dorsiflexor strength. [Results] The results showed (1) a moderate correlation between ankle dorsiflexor strength and dorsiflexion range of motion and (2) a moderate correlation between ankle dorsiflexor strength and first toe flexor muscle strength. Ankle dorsiflexor strength is the main contributor ankle dorsiflexion range of motion to and first toe flexor muscle strength. [Conclusion] Ankle dorsiflexion range of motion can play an important role in determining ankle dorsiflexor strength in young adults.

10.
J Strength Cond Res ; 30(9): 2493-9, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24448004

RESUMEN

García-López, D, Hernández-Sánchez, S, Martín, E, Marín, PJ, Zarzosa, F, and Herrero, AJ. Free-weight augmentation with elastic bands improves bench press kinematics in professional rugby players. J Strength Cond Res 30(9): 2493-2499, 2016-This study aimed to investigate the effects of combining elastic bands to free weight resistance (EB + FWR) on the acceleration-deceleration and velocity profiles of the bench press in professional rugby players and recreationally trained subjects. Sixteen male subjects (8 rugby players and 8 recreationally trained subjects) were randomly assigned to complete 2 experimental conditions in a crossover fashion: EB + FWR and FWR. In both conditions, subjects performed 1 bench press set to volitional exhaustion with a load equivalent to the 85% of 1 repetition maximum (1RM). In the EB + FWR condition, the contribution of elastic resistance was approximately 20% of the selected load (85% 1RM). Results indicate that EB + FWR condition increased significantly the range of concentric movement in which the barbell is accelerated. This increase was significantly higher in rugby players (35%) in comparison with recreationally trained subjects (13%). Maximal velocity was also increased in EB + FWR (17%), when compared with FWR condition. These results suggest that when combined with variable resistance (i.e., EB), the external resistance seems to be more evenly distributed over the full range of motion, decreasing the need for dramatic deceleration at the end of the concentric phase. The present data also indicate that the kinematic benefits of an EB + FWR approach seems to be more prominent in athletes from modalities in which high level of strength and power are required (i.e., rugby players).


Asunto(s)
Rendimiento Atlético/fisiología , Entrenamiento de Fuerza , Levantamiento de Peso/fisiología , Adulto , Fenómenos Biomecánicos/fisiología , Estudios Cruzados , Fútbol Americano/fisiología , Humanos , Masculino , Fuerza Muscular/fisiología , Distribución Aleatoria , Adulto Joven
11.
Eur J Appl Physiol ; 115(8): 1747-55, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25820213

RESUMEN

PURPOSE: The aim of this study was to analyze the acute effects of isolated or simultaneously applied whole-body vibration (WBV) and electromyostimulation (ES) on the popliteal arterial blood velocity and skin temperature (ST) of the calf. METHODS: Thirteen healthy males were assessed in five different sessions. After a familiarization session, four interventions were applied in random order; WBV, ES, simultaneous WBV and ES (WBV+ES), and 30 s of WBV followed by 30 s of ES (WBV30/ES30). Each intervention consisted of 10 sets × 1 min ON + 1 min OFF. The subject was standing on the vibration platform (squat position, 30° knee flexion, 26 Hz, 5 mm peak-to-peak), and ES was applied on the gastrocnemius of both the legs (8 Hz, 400 µs). RESULTS: The WBV+ES intervention was the only one that maintained the mean blood velocity (MBV) elevated above baseline during the 10 sets, from set-1 (134.6 % p < 0.01) to set-10 (112.6 % p < 0.05). The combined interventions were the only ones that maintained the peak blood velocity (PBV) elevated above baseline during all the sets, from set-1 (113.5 % p < 0.001) to set-10 (88.8 % p < 0.01) and from set-1 (58.4 % p < 0.01) to set-10 (49.1 % p < 0.05) for WBV+ES and WBV30/ES30, respectively. CONCLUSION: The simultaneous application of WBV and ES produced a general greater increase in MBV and PBV than the application of each method alone or consecutive. This novel methodological proposal could be interesting in different fields such as sports or the rehabilitation process of different pathologies, to achieve an enhanced peripheral blood flow.


Asunto(s)
Estimulación Eléctrica , Pierna/irrigación sanguínea , Pierna/fisiología , Músculo Esquelético/fisiología , Vibración , Humanos , Pierna/diagnóstico por imagen , Masculino , Estimulación Física , Arteria Poplítea/fisiología , Desempeño Psicomotor/fisiología , Flujo Sanguíneo Regional/fisiología , Temperatura Cutánea/fisiología , Ultrasonografía , Adulto Joven
12.
J Strength Cond Res ; 29(10): 2881-7, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25807029

RESUMEN

The purpose of this study was to examine the effects (a) of different whole-body vibration (WBV) accelerations when applied simultaneously during a set of squats on performance and perceived exertion and (b) of different linear increases and decreases of vibrations during the squats. It is a randomized, crossover experimental design. Undergraduate students (3 female; 16 male) participated. Each participant completed 5 laboratory sessions in this study (4 familiarization and 1 test session). The test session then had each participant complete one 20-second set of dynamics quarter-squats for 5 separate conditions followed by 5 minutes of rest. Squatting was performed at maximum speed from full extension knee with plantar-flexion ankle to a knee angle of 70° (0° = anatomic position) with dorsiflexion ankle. All sets were performed on the WBV platform in random order, where the 5 different conditions were (a) no WBV-sham, (b) 30 Hz (30 Hz low amplitude), (c) 50 Hz (50 Hz high amplitude), (d) 30-50 Hz (increasing frequency from 30 to 50 Hz; 1 Hz per second with high amplitude), and (e) 50-30 Hz (decreasing frequency from 50 to 30 Hz; 1 Hz per second). There was a significant decrease in the mean velocity of squatting performed during the 30- to 50-Hz condition compared with all other conditions (p ≤ 0.05). There were a significantly lower amount of repetitions performed during the 30- to 50-Hz exposure compared with the no-WBV and 30-Hz conditions. There was a significantly lower Rating of Perceived Exertion (RPE) during the 30-Hz condition compared with the no-WBV, 50-Hz, 30-50-Hz, and 50-30-Hz conditions.


Asunto(s)
Ejercicio Físico/fisiología , Vibración , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Esfuerzo Físico/fisiología , Adulto Joven
13.
J Strength Cond Res ; 27(9): 2433-43, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23287831

RESUMEN

Much recent attention has been given to the compatibility of combined aerobic and anaerobic training modalities. However, few of these studies have reported data related to well-trained runners, which is a potential limitation. Therefore, because of the limited evidence available for this population, the main aim was to determine which mode of concurrent strength-endurance training might be the most effective at improving running performance in highly trained runners. Eighteen well-trained male runners (age 23.7 ± 1.2 years) with a maximal oxygen consumption (VO2max) more than 65 ml·kg(-1)·min(-1) were randomly assigned into 1 of the 3 groups: Endurance-only Group (n = 6), who continued their usual training, which included general strength training with Thera-band latex-free exercise bands and endurance training; Strength Group (SG; n = 6) who performed combined resistance and plyometric exercises and endurance training; Endurance-SG (ESG; n = 6) who performed endurance-strength training with loads of 40% and endurance training. The study comprised 12 weeks of training in which runners trained 8 times a week (6 endurance and 2 strength sessions) and 5 weeks of detraining. The subjects were tested on 3 different occasions (countermovement jump height, hopping test average height, 1 repetition maximum, running economy (RE), VO2max, maximal heart rate [HRmax], peak velocity (PV), rating of perceived exertion, and 3-km time trial were measured). Findings revealed significant time × group interaction effects for almost all tests (p < 0.05). We can conclude that concurrent training for both SG and ESG groups led to improved maximal strength, RE, and PV with no significant effects on the VO2 kinetics pattern. The SG group also seems to show improvements in 3-km time trial tests.


Asunto(s)
Rendimiento Atlético/fisiología , Fuerza Muscular/fisiología , Resistencia Física/fisiología , Entrenamiento de Fuerza , Carrera/educación , Rendimiento Atlético/educación , Humanos , Masculino , Entrenamiento de Fuerza/métodos , Carrera/fisiología , Adulto Joven
14.
J Strength Cond Res ; 27(7): 1807-12, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23085972

RESUMEN

Whole-body vibration (WBV) training has exercisers perform static and dynamic resistance training exercises on a ground-based platform. Exposure to WBV exposure has demonstrated benefits and no effect on lower body strength, power, and performance. The aim of this study was to determine if WBV exposure (50 Hz, 2.51 mm) has any potentiating effects postexercise by measuring the kinematic variables of a set of upper body elbow-extensor exercise (70% one-repetition maximum [1RM]) to volitional exhaustion. Sixteen recreationally active students (12 male and 4 female) performed 3 different experimental conditions on separate days. Each condition had the subjects perform 1 set of elbow-extension exercise to fatigue with 1 of 3 WBV treatments: WBV simultaneously during the set (AE); 60 seconds after application of WBV for 30 seconds (RE); and no WBV (CTRL). Kinematic parameters of each repetition were monitored by linking a rotary encoder to the highest load plate. The mean velocity and acceleration throughout the set and perceived exertion were analyzed. A significant increase (p < 0.05) was observed in the mean velocity for the whole set in the AE condition vs. the CTRL condition. The mean acceleration was significantly higher (p < 0.05) in the AE condition in comparison with RE (increased by 45.3%) and CTRL (increased by 50.4%) conditions. The positive effect induced by WBV on upper-limb performance is only achieved when the stimulus is applied during the exercise. However, WBV applied 60 seconds before upper body exercise results in no benefit.


Asunto(s)
Entrenamiento de Fuerza/métodos , Extremidad Superior/fisiología , Vibración , Aceleración , Fenómenos Biomecánicos , Femenino , Humanos , Masculino , Fuerza Muscular/fisiología , Músculo Esquelético/fisiología , Adulto Joven
15.
J Strength Cond Res ; 27(3): 854-9, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22580978

RESUMEN

There is no clear agreement regarding the ideal combination of factors needed to optimize postactivation potentiation (PAP) after a conditioning activity. Therefore, a meta-analysis was conducted to evaluate the effects of training status, volume, rest period length, conditioning activity, and gender on power augmentation due to PAP. A total of 141 effect sizes (ESs) for muscular power were obtained from a total of 32 primary studies, which met our criteria of investigating the effects of a heavy preconditioning activity on power in randomized human trials. The mean overall ES for muscle power was 0.38 after a conditioning activity (p < 0.05). Significant differences were found between moderate intensity (60-84%) 1.06 and heavy intensity (>85%) 0.31 (p < 0.05). There were overall significant differences found between single sets 0.24 and multiple sets 0.66 (p < 0.05). Rest periods of 7-10 minutes (0.7) after a conditioning activity resulted in greater ES than 3-7 minutes (0.54), which was greater than rest periods of >10 minutes (0.02) (p < 0.05). Significant differences were found between untrained 0.14 and athletes 0.81 and between trained 0.29 and athletes. The primary findings of this study were that a conditioning activity augmented power output, and these effects increased with training experience, but did not differ significantly between genders. Moreover, potentiation was optimal after multiple (vs. single) sets, performed at moderate intensities, and using moderate rest periods lengths (7-10 minutes).


Asunto(s)
Músculo Esquelético/fisiología , Esfuerzo Físico/fisiología , Descanso/fisiología , Atletas , Electromiografía , Humanos , Contracción Muscular/fisiología , Aptitud Física/fisiología , Factores Sexuales
16.
Sports Biomech ; 22(5): 633-659, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-32336212

RESUMEN

The assessment of the mechanical power production is of great importance for researchers and practitioners. The purpose of this review was to compare the differences in ground reaction force (GRF), kinematic, and combined (bar velocity x GRF) methods to assess mechanical power production during weightlifting exercises. A search of electronic databases was conducted to identify all publications up to 31 May 2019. The peak power output (PPO) was selected as the key variable. The exercises included in this review were clean variations, which includes the hang power clean (HPC), power clean (PC) and clean. A total of 26 articles met the inclusion criteria with 53.9% using the GRF, 38.5% combined, and 30.8% the kinematic method. Articles were evaluated and descriptively analysed to enable comparison between methods. The three methods have inherent methodological differences in the data analysis and measurement systems, which suggests that these methods should not be used interchangeably to assess PPO in Watts during weightlifting exercises. In addition, this review provides evidence and rationale for the use of the GRF to assess power production applied to the system mass while the kinematic method may be more appropriate when looking to assess only the power applied to the barbell.


Asunto(s)
Músculo Esquelético , Levantamiento de Peso , Humanos , Fenómenos Biomecánicos , Ejercicio Físico , Fuerza Muscular
17.
Eur J Appl Physiol ; 112(5): 1849-59, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-21922259

RESUMEN

The primary objective of this investigation was to quantitatively identify which training variables result in the greatest strength and hypertrophy outcomes with lower body low intensity training with blood flow restriction (LI-BFR). Searches were performed for published studies with certain criteria. First, the primary focus of the study must have compared the effects of low intensity endurance or resistance training alone to low intensity exercise with some form of blood flow restriction. Second, subject populations had to have similar baseline characteristics so that valid outcome measures could be made. Finally, outcome measures had to include at least one measure of muscle hypertrophy. All studies included in the analysis utilized MRI except for two which reported changes via ultrasound. The mean overall effect size (ES) for muscle strength for LI-BFR was 0.58 [95% CI: 0.40, 0.76], and 0.00 [95% CI: -0.18, 0.17] for low intensity training. The mean overall ES for muscle hypertrophy for LI-BFR training was 0.39 [95% CI: 0.35, 0.43], and -0.01 [95% CI: -0.05, 0.03] for low intensity training. Blood flow restriction resulted in significantly greater gains in strength and hypertrophy when performed with resistance training than with walking. In addition, performing LI-BFR 2-3 days per week resulted in the greatest ES compared to 4-5 days per week. Significant correlations were found between ES for strength development and weeks of duration, but not for muscle hypertrophy. This meta-analysis provides insight into the impact of different variables on muscular strength and hypertrophy to LI-BFR training.


Asunto(s)
Ejercicio Físico/fisiología , Hipertrofia/fisiopatología , Fuerza Muscular/fisiología , Músculo Esquelético/irrigación sanguínea , Entrenamiento de Fuerza/métodos , Velocidad del Flujo Sanguíneo , Femenino , Hemodinámica , Humanos , Masculino , Músculo Esquelético/fisiología , Flujo Sanguíneo Regional
18.
J Strength Cond Res ; 26(4): 941-6, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22446667

RESUMEN

This study aimed to examine the relationship existing between maximum strength values in 2 common resistance training row exercises (bilateral bench pull [BBP] and one-arm cable row [OACR]) and short sprint performance in elite kayakers. Ten junior kayakers (5 women and 5 men) were tested on different days for 1 repetition maximum (1RM) and maximal voluntary isometric contraction in both exercises. Moreover, a 12-m sprint kayak was performed in a dew pond to record split times (2, 5, and 10 m), peak velocity, distance completed considering the first 8 strokes, and mean acceleration induced by right blade and left blade strokes. No differences (p > 0.05) were observed when right and left arms were compared in sprint testing or strength testing variables. Maximal strength values in BBP and OACR were significantly correlated with short sprint performance variables, showing the bilateral exercise with slightly stronger correlation coefficients than the unilateral seated row. Moreover, the relationship between strength testing and sprint testing variables is stronger when maximal force is measured through a dynamic approach (1RM) in comparison with an isometric approach. In conclusion, maximal strength in BBP and OACR is a good predictor of the start phase performance in elite sprint kayakers, mainly the 1RM value in BBP.


Asunto(s)
Rendimiento Atlético/fisiología , Fuerza Muscular/fisiología , Entrenamiento de Fuerza , Adolescente , Brazo/fisiología , Femenino , Humanos , Contracción Isométrica/fisiología , Masculino , Músculo Esquelético/fisiología , Hombro/fisiología , Adulto Joven
19.
J Strength Cond Res ; 26(1): 232-9, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22158143

RESUMEN

The aim of this study was to analyze surface electromyography activity (sEMG) and rating of perceived exertion (RPE) responses in different muscles while standing on a vibrating platform producing oscillations of different frequencies and amplitudes. Twenty community-dwelling older adults (79.6 ± 3.2 years) took part in the research. Subjects were exposed to 12 different vibration treatments of 15 seconds separated by 1 minute of rest in random order to check the influence of frequency (25, 35, and 45 Hz) and amplitude (1 mm [low] and 3.1 mm [high]) vibration on sEMG signal and RPE. Additionally, the use of a soft pad was also examined for its influence on these measures. Three-factor analysis of variance for RPE and both lower and whole-body sEMGs revealed a significant amplitude main effect (p < 0.01), and soft mat effect (p < 0.01), and a significant frequency main effect (p < 0.01). The major findings were that sEMG and RPE increased with the acceleration of the vibration; moreover, the increments of sEMG were highly correlated with RPE. The results of this study suggest that using the RPE method after each exercise would allow exercise and health professionals to assess the intensity levels that correspond to the level of the vibratory program in older adults.


Asunto(s)
Músculo Esquelético/fisiología , Vibración/uso terapéutico , Anciano , Electromiografía , Femenino , Humanos , Masculino , Esfuerzo Físico/fisiología
20.
J Strength Cond Res ; 26(8): 2293-307, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22002517

RESUMEN

The primary objective of this investigation was to identify which components of endurance training (e.g., modality, duration, frequency) are detrimental to resistance training outcomes. A meta-analysis of 21 studies was performed with a total of 422 effect sizes (ESs). Criteria for the study included were (a) compare strength training alone to strength plus endurance training (concurrent) or to compare combinations of concurrent training; (b) the outcome measures include at least one measure of strength, power, or hypertrophy; and (c) the data necessary to calculate ESs must be included or available. The mean ES for hypertrophy for strength training was 1.23; for endurance training, it was 0.27; and for concurrent training, it was 0.85, with strength and concurrent training being significantly greater than endurance training only. The mean ES for strength development for strength training was 1.76; for endurance training, it was 0.78; and for concurrent training, it was 1.44. Strength and concurrent training was significantly greater than endurance training. The mean ES for power development for strength training only was 0.91; for endurance training, it was 0.11; and for concurrent training, it was 0.55. Significant differences were found between all the 3 groups. For moderator variables, resistance training concurrently with running, but not cycling, resulted in significant decrements in both hypertrophy and strength. Correlational analysis identified significant negative relationships between frequency (-0.26 to -0.35) and duration (-0.29 to -0.75) of endurance training for hypertrophy, strength, and power. Significant relationships (p < 0.05) between ES for decreased body fat and % maximal heart rate (r = -0.60) were also found. Our results indicate that interference effects of endurance training are a factor of the modality, frequency, and duration of the endurance training selected.


Asunto(s)
Ejercicio Físico/fisiología , Entrenamiento de Fuerza , Femenino , Humanos , Masculino , Fuerza Muscular/fisiología , Músculo Esquelético/fisiología , Consumo de Oxígeno , Resistencia Física/fisiología , Carrera/fisiología
SELECCIÓN DE REFERENCIAS
Detalles de la búsqueda