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1.
J Strength Cond Res ; 31(2): 359-364, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28125544

RESUMEN

Karampatsos, GP, Korfiatis, PG, Zaras, ND, Georgiadis, GV, and Terzis, GD. Acute effect of countermovement jumping on throwing performance in track and field athletes during competition. J Strength Cond Res 32(1): 359-364, 2017-The purpose of the study was to investigate whether performing 3 consecutive countermovement jumps (CMJs) just before an attempt enhances performance in track and field throwers during competition. Twelve shot putters, 8 hammer throwers, 9 discus throwers, and 3 javelin throwers of both sexes participated in the study. They performed 3 maximal CMJs 85 ± 12 seconds before the second, fourth, and sixth attempt during 3 different official competitions of national level. Maximal strength (1 repetition maximum [1RM]) in squat and bench press was measured 1 week after the competition. Mean throwing performance was significantly higher after the CMJs intervention (2.66 ± 4.3%, range of increase 0.02-18.98%, p = 0.0001). Similarly, maximum throwing performance was significantly higher after the CMJs (2.76 ± 3.29%, range of increase 0.09-13.93%, p = 0.0009). All but 2 athletes increased their best performance after the CMJs. The percentage increase in performance was similar between sexes (male athletes 2.56 ± 3.01%; female athletes 3.06 ± 3.76%, p = 0.677), but it was higher for the "lighter throws" (discus and javelin throw: 4.66 ± 4.11%) compared with the "heavier throws" (shot and hammer throw: 1.62 ± 2.04%, p = 0.008). The percentage increase in performance was not significantly correlated with 1RM squat or bench press, anthropometric characteristics, and personal best performance. These results suggest that performing 3 CMJs approximately 1 minute before an attempt may increase track and field throwing performance during competition.


Asunto(s)
Atletas , Rendimiento Atlético/fisiología , Atletismo/fisiología , Adulto , Ejercicio Físico , Femenino , Humanos , Masculino , Fuerza Muscular , Músculo Esquelético , Factores Sexuales , Adulto Joven
2.
J Strength Cond Res ; 30(4): 1033-41, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26349048

RESUMEN

The aim of the study was to examine whether physical and technical performance deterioration after a water polo game is related to the athletes' conditioning level. Blood lactate concentration was measured during a 5 × 200-m incremental swimming test in 10 male water polo athletes to calculate the velocities corresponding to 4.0, 5.0, and 10.0 mmol·L lactate concentration (V4, V5, and V10, respectively) and define their conditioning level. All athletes participated in 5 competitive water polo games. Before (Pre), at half time (Mid), and after (Post) the first 2 games, handgrip strength and repeated sprint ability (8 × 20-m) were measured. Pre and Post the next 2 games, ball throwing velocity, shooting accuracy, and 400-m swim were evaluated. Pre, Mid, and Post the last game, the eggbeater kick test was performed. Handgrip strength, repeated sprint ability, 400-m swim performance, and ball shooting accuracy decreased after the game (8.4 ± 6.2%, 6.3 ± 3.4%, 7.0 ± 4.1%, and 20.3 ± 23.4%, respectively, p ≤ 0.05). V4, V5, and V10 were not significantly correlated with changes in physical or technical performance after the game. Performance in 400-m swim correlated with V4 and V5 whereas changes in 400-m swim Pre-Post, correlated with changes in ball shooting accuracy and throwing velocity (r = 0.73 and r = 0.80, p ≤ 0.05). These data suggest that V4, V5, and V10 may not correlate with performance decline in water polo. Interestingly, the 400-m swim test is connected with the decline in repeated sprints, ball shooting accuracy, and throwing velocity after a water polo game in well-trained athletes.


Asunto(s)
Rendimiento Atlético/fisiología , Ácido Láctico/sangre , Aptitud Física/fisiología , Deportes/fisiología , Adulto , Prueba de Esfuerzo , Fuerza de la Mano , Humanos , Masculino , Natación/fisiología , Adulto Joven
3.
J Strength Cond Res ; 30(3): 807-17, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26907845

RESUMEN

The aim of the study was to examine the correlation between muscle morphology and jumping, sprinting, and throwing performance in participants with different power training duration experience. Thirty-six power-trained young men were assigned to 3 groups according to the length of their power training: less experienced (<1 year), moderately experienced (1-3 years), and experienced (4-7 years). All participants performed countermovement and squat jumps, 60-m sprint, and shot throws twice. Lean body mass (LBM) was evaluated with dual-energy x-ray absorptiometry and thigh muscle cross-sectional area (CSA) with anthropometry. The vastus lateralis architecture and fiber type composition were evaluated with ultrasonography and muscle biopsies, respectively. When all subjects were considered as 1 group (n = 36), jumping performance was correlated with LBM, fascicle length, and type II fiber CSA; sprinting performance was correlated with estimated thigh muscle CSA alone; and shot throwing was correlated with LBM and type I, IIA fiber CSA. In the least experienced group, the LBM of the lower extremities was the most significant contributor for power performance, whereas in the moderately experienced group, the LBM, architectural properties, and type II fiber percentage CSA were the most significant contributors. For the experienced group, fascicle length and type II fiber percentage CSA were the most significant factors for power performance. These data suggest that jumping performance is linked with muscle morphology, regardless of strength or power training. The vastus lateralis muscle morphology could only partially explain throwing performance, whereas it cannot predict sprinting performance. Power performance in experienced participants rely more on the quality of the muscle tissue rather than the quantity.


Asunto(s)
Rendimiento Atlético/fisiología , Ejercicio Físico/fisiología , Fibras Musculares de Contracción Rápida/citología , Músculo Cuádriceps/anatomía & histología , Entrenamiento de Fuerza , Absorciometría de Fotón , Adolescente , Adulto , Composición Corporal , Prueba de Esfuerzo , Humanos , Masculino , Fibras Musculares de Contracción Rápida/diagnóstico por imagen , Músculo Cuádriceps/diagnóstico por imagen , Músculo Cuádriceps/fisiología , Carrera/fisiología , Factores de Tiempo , Ultrasonografía , Adulto Joven
4.
J Strength Cond Res ; 30(1): 81-92, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26049793

RESUMEN

The rate of force development (RFD) is an essential component for performance in explosive activities, although it has been proposed that muscle architectural characteristics might be linked with RFD and power performance. The purpose of the study was to investigate the relationship between RFD, muscle architecture, and performance in young track and field throwers. Twelve young track and field throwers completed 10 weeks of periodized training. Before (T1) and after (T2) training performance was evaluated in competitive track and field throws, commonly used shot put tests, isometric leg press RFD, 1 repetition maximum (1RM) strength as well as vastus lateralis architecture and body composition. Performance in competitive track and field throwing and the shot put test from the power position increased by 6.76 ± 4.31% (p < 0.001) and 3.58 ± 4.97% (p = 0.019), respectively. Rate of force development and 1RM strength also increased (p ≤ 0.05). Vastus lateralis thickness and fascicle length increased by 5.95 ± 7.13% (p = 0.012) and 13.41 ± 16.15% (p = 0.016), respectively. Significant correlations were found at T1 and T2, between performance in the shot put tests and both RFD and fascicle length (p ≤ 0.05). Close correlations were found between RFD, muscle thickness, and fascicle length (p ≤ 0.05). Significant correlations were found between the % changes in lean body mass and the % increases in RFD. When calculated together, the % increase in muscle thickness and RFD could predict the % increase in shot put throw test from the power position (p = 0.019). These results suggest that leg press RFD may predict performance in shot put tests that are commonly used by track and field throwers.


Asunto(s)
Rendimiento Atlético/fisiología , Músculo Cuádriceps/anatomía & histología , Músculo Cuádriceps/fisiología , Atletismo/fisiología , Adolescente , Adulto , Composición Corporal , Prueba de Esfuerzo , Femenino , Humanos , Masculino , Tamaño de los Órganos , Acondicionamiento Físico Humano/fisiología , Adulto Joven
5.
J Strength Cond Res ; 28(12): 3484-95, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24910954

RESUMEN

The purpose of the study was to investigate the effects of power training with light vs. heavy loads during the tapering phases of a double periodized training year on track and field throwing performance. Thirteen track and field throwers aged 16-26 years followed 8 months of systematic training for performance enhancement aiming at 2 tapering phases during the winter and the spring competition periods. Athletes performed tapering with 2 different resistance training loads (counterbalanced design): 7 athletes used 30% of 1 repetition maximum (1RM) light-load tapering (LT), and 6 athletes used the 85% of 1RM heavy-load tapering (HT), during the winter tapering. The opposite was performed at the spring tapering. Before and after each tapering, throwing performance, 1RM strength, vertical jumping, rate of force development (RFD), vastus lateralis architecture, and rate of perceived exertion were evaluated. Throwing performance increased significantly by 4.8 ± 1.0% and 5.6 ± 0.9% after LT and HT, respectively. Leg press 1RM and squat jump power increased more after HT than LT (5.9 ± 3.2% vs. -3.4 ± 2.5%, and 5.1 ± 2.4% vs. 0.9 ± 1.4%, respectively, p ≤ 0.05). Leg press RFD increased more in HT (38.1 ± 16.5%) compared with LT (-2.9 ± 6.7%), but LT induced less fatigue than HT (4.0 ± 1.5 vs. 6.7 ± 0.9, p ≤ 0.05). Muscle architecture was not altered after either program. These results suggest that performance increases similarly after tapering with LT or HT in track and field throwers, but HT leads to greater increases in strength, whole body power, and RFD.


Asunto(s)
Rendimiento Atlético/fisiología , Entrenamiento de Fuerza/métodos , Atletismo , Extremidad Superior/fisiología , Adolescente , Adulto , Femenino , Humanos , Masculino , Fuerza Muscular/fisiología , Distribución Aleatoria , Adulto Joven
6.
Int J Sports Physiol Perform ; 17(8): 1264-1271, 2022 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-35894996

RESUMEN

PURPOSE: To examine the effect of dryland training during an 11-week lockdown period due to COVID-19 on swimming performance. METHODS: Twelve competitive swimmers performed 50- and 300-m maximum-effort tests in their preferred stroke and 200-, 400-, and four 50-m front crawl sprints (4 × 50 m) before and after the lockdown period. Critical speed as an index of aerobic endurance was calculated using (1) 50-, 300-, and (2) 200-, 400-m tests. Blood lactate concentration was measured after the 400- and 4 × 50-m tests. To evaluate strength-related abilities, the dryland tests included handgrip and shoulder isometric strength. Tethered swimming force was measured during a 10-second sprint. During the lockdown period, dryland training was applied, and the session rating of perceived exertion training (sRPE) load was recorded daily. RESULTS: sRPE training load during the lockdown was decreased by 78% (16%), and critical speed was reduced 4.7% to 4.9% compared to prelockdown period (P < .05). Performance time in 200, 300, and 400 m deteriorated 2.6% to 3.9% (P < .05), while it remained unaltered in 4 × 50- and 50-m tests (P > .05). Tethered force increased 9% (10%) (P < .01), but handgrip and shoulder isometric force remained unaltered (P > .05). Blood lactate concentration decreased 19% (21%) after the 400-m test and was unchanged following the 4 × 50-m tests (P > .05). CONCLUSIONS: Performance deterioration in the 200, 300, and 400 m indicates reduced aerobic fitness and impaired technical ability, while strength and repeated-sprint ability were maintained. When a long abstention from swimming training is forced, dryland training may facilitate preservation in short-distance but not middle-distance swimming performance.


Asunto(s)
Rendimiento Atlético , COVID-19 , COVID-19/prevención & control , Control de Enfermedades Transmisibles , Fuerza de la Mano , Humanos , Ácido Láctico , Natación
7.
J Hum Kinet ; 67: 175-184, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31523316

RESUMEN

The purpose of the study was to examine changes in performance and match-induced fatigue over a 27-week training period. Eight national-level water-polo players performed a 5 x 200 m swimming test to calculate velocities corresponding to blood lactate concentration of 4.0, 5.0 and 10.0 mmol.l-1 at three testing periods: i) baseline, ii) end of the pre-season (8 weeks of 4 x 4 min swimming bouts), iii) end of the in-season (8 weeks of 8 x 20 m swimming sprints). During each testing period, four competitive matches were played and repeated sprints (8 x 20 m), 400 m swimming, and shooting accuracy were evaluated at the pre- and post-match. Repeated sprint tests were also conducted at mid-game. Analysis of variance for repeated measures was used to detect changes among training periods and within games. Swimming velocities corresponding to 4.0, 5.0 and 10.0 mmol.l-1 were increased after the pre-season by 9%, 7.7%, and 6.7% (p < 0.01) and decreased following the in-season compared to the pre-season by 8.9%, 7.0% and 3.3% (p < 0.01), respectively. Pre-match repeated sprints and 400 m performance were improved after the pre-season by 4.3% and 3.8% (p < 0.01) and decreased by ~3% after the in-season compared to the pre-season (p < 0.01). Mid- and post-match repeated sprint performance was improved after the pre-season by 4.8 ± 1.4% and 4.4 ± 1.1% and remained unchanged after the in-season compared to the pre-season. Post-match 400 m speed was improved by 3.2% after the pre-season (p < 0.01) and decreased by 2.8% after the in-season (p = 0.04).Pre-season training improved players' aerobic endurance and performance. Intensified in-season training decreased aerobic power, endurance, and pre-match performance while maintaining match repeated sprint performance.

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