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1.
Sci Rep ; 13(1): 19593, 2023 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-37950054

RESUMEN

This study investigated the impact of active rest intervals within a lower body complex training session on post-activation performance enhancement (PAPE) response in amateur soccer players. Twelve soccer players took part in four different experimental conditions. These sessions included 2 sets of lower body complex-paired exercises, each involving 3 repetitions of either back squats or hip thrusts at 90% one-repetition maximum (1RM) as a conditioning activity paired with a broad jump and countermovement jump. Between those exercises in active intra-complex rest interval conditions, participants were performing 8 repetitions of bench press at 75%1RM or, in passive intra-complex rest interval conditions, rested while seated. A significant main effect of a set to increase broad jump length (p = 0.002), countermovement jump height (p = 0.002), and modified reactive strength index (p = 0.005) was revealed, without any significant differences between conditions. Post-hoc comparisons showed a significant increase in broad jump length from baseline to Set-2 (231 ± 13 vs. 234 ± 13 cm; p = 0.003; ES = 0.22). On the other hand, countermovement jump height and modified reactive strength index significantly increased from baseline to Set-1 (34.4 ± 3.6 vs. 35.6 ± 3.9 cm; p = 0.027; ES = 0.31 and 0.4 ± 0.05 vs. 0.45 ± 0.09; p = 0.005; ES = 0.66). Results of this study showed that to sustain a high training density, sports practitioners may incorporate upper body exercises within the intra-complex rest interval during lower limb complex training sessions and still elicit a significant PAPE effect.


Asunto(s)
Fútbol , Deportes , Humanos , Deportes/fisiología , Postura , Ejercicio Físico , Atletas
2.
Sports (Basel) ; 11(7)2023 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-37505611

RESUMEN

The objective of this study was to compare (i) The effects of a flywheel and free-weight resistance training program; and (ii) The effects of performing lateral and frontal split squats as part of a flywheel-resistance training program on jumping performance, the 5-0-5 change of direction test time, and the one-repetition maximum (1RM) back squat in soccer players. Twenty-four male amateur soccer players participated in this study and were randomly and equally assigned to one of three different test groups: forward split-squat group (FSQ); lateral split-squat group (LSQ); and free-weight training group (TRAD). Athletes in the FSQ group performed a squat and a forward split squat on a flywheel device, while those in the LSQ group performed a squat and a lateral split squat (instead of a forward split squat) on a flywheel device. Each training lasted 4 weeks. The main finding was that all training groups, such as TRAD, FSQ, and LSQ, significantly improved broad jump length (p = 0.001; effect size [ES] = 0.36), 5-0-5 COD time with a turn on the dominant limb (p = 0.038; ES = 0.49), and 1RM back squat (p = 0.001; ES = 0.4). In turn, both flywheel-resistance training groups (FSQ and LSQ) significantly improved their counter-movement jump height (p = 0.001; ES = 0.8 and p = 0.002; ES = 0.58; respectively) with no effect in the TRAD (p = 0.676; ES = 0.07) training group. Both free-weight and flywheel-resistance training lasting 4 weeks performed in-season contributed to significant improvement in 1RM back squat, broad jump performance, and 5-0-5 change of direction testing time, while flywheel-resistance training might be superior in counter-movement jump height enhancement in soccer players. Moreover, the manner in which split squats were performed was not a factor influencing the obtained results.

3.
Sci Rep ; 13(1): 7411, 2023 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-37150765

RESUMEN

The aim of this study was to examine whether acute whole-body vibration, a single bout of drop jumps, or a combination of both may enhance countermovement jump (CMJ) and would affect volitional pace 3 km running performance. Twelve healthy and recreationally active males completed 4 conditions in randomized order: (i) 5 sets of 30 s calf raises on the platform but without vibration; (ii) 5 sets of 30 s calf raises on the vibration platform with 30 s rest intervals between sets; (iii) 5 sets of 6 drop jump with a 30 s rest interval between sets; (iv) 5 sets of 30 s calf raises on the vibration platform followed by 6 drop jumps with a 30 s rest interval between sets. Before, 3-min after, and immediately after a 3 km run each participant performed CMJ. No significant difference between conditions (p = 0.327) for the 3 km time trial was found. Whereas CMJ height and relative peak power were significantly improved in post-3 km run than at baseline (p < 0.001 and p = 0.025) and post-warm-up (p = 0.001 and p = 0.002) in all conditions. The present study indicates that warm-up consisting of either whole-body vibration, drop jumps, or a combination of both failed to acutely improve CMJ and 3 km volitional pace running performance in physically active males. However, the increase in the CMJ performance was noted after the end of the 3 km run, which may indicate that the warm-up protocols used were insufficient to enhance subsequent performance.


Asunto(s)
Rendimiento Atlético , Carrera , Ejercicio de Calentamiento , Humanos , Masculino , Pierna , Músculo Esquelético , Descanso , Vibración
4.
Sensors (Basel) ; 23(7)2023 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-37050508

RESUMEN

Researchers involved in skiing investigations postulate Telemark skiing as an alternative technique to Alpine skiing, which may be associated with lower injury risk. A free heel of the boot, and a boot that enables flexion of the toe, are characteristic features. The aim of this research was to compare three types of turns on Telemark skis, through a biomechanical description of each skiing technique. Seven professional skiers were investigated. Two cameras and the MyoMotion Research Pro system were utilized. Eighteen wireless IMU sensors were mounted on each skier's body. For every skier, five runs were recorded for each of the three turning techniques. Velocity of run, range of movement, angular velocity in joints, time sequences, and order of initialization of movement were obtained. A higher velocity of skiing was obtained during the parallel (14.2 m/s) and rotational turns (14.9 m/s), compared to a low-high turn (8.9 m/s). A comparison of knee angles, revealed similar minimum (18 and 16 degrees) and maximum (143 and 147 degrees) values achieved during the parallel and rotational techniques, which differed considerably from the low-high technique (27 and 121 degrees, respectively). There were no significant differences in trunk rotation angles. A detailed analysis of the Telemark skiing technique revealed novel information on how turns are executed by well-trained skiers and the impact of different approaches.


Asunto(s)
Esquí , Movimiento , Articulación de la Rodilla , Rango del Movimiento Articular , Fenómenos Biomecánicos
5.
J Sports Sci Med ; 21(4): 625-639, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36523899

RESUMEN

This review aimed to summarize the reported effects of unilateral conditioning activity (CA) on unilateral performance, bilateral performance, and the contribution of activated body limb to bilateral performance. A systematic search on MEDLINE, SPORTDiscus, Scopus, and Google Scholar was conducted on February 2022. Twenty-three studies met the inclusion criteria. Throwing, jumping, swimming, change of direction, and isokinetic performance were used as outcome measures to assess the impact of unilateral CAs on inducing post-activation performance enhancement. Eleven studies examined the effectiveness of resistance exercises as a CA, seven investigated plyometric exercises, and five used isokinetic muscle actions as CAs. Notably, only three studies directly compared the effects of bilateral and unilateral CA, and no study reported possible changes in the contribution of each limb during bilateral exercises executed following unilateral CA. Split squats were the most often studied CA (7), and it was shown that multiple sets of high-loaded split squats (85% one-repetition maximum) executed as CA, improve vertical jumping and change of direction after 4 to 8 min of recovery. At the same time, multiple sets of alternate leg bounds performed with ~10% body weight or without any external load result in an improvement of sprint performance, 2 and 8 min later, with the effect being greater when loaded jumps are used. The unilateral CAs such as split squats, alternate leg bounds, and drop jumps can be effectively used to acutely improve a wide variety of athletic tasks, including jumping, sprinting, change of direction, and swimming performance.


Asunto(s)
Rendimiento Atlético , Ejercicio Pliométrico , Humanos , Rendimiento Atlético/fisiología , Ejercicio Físico/fisiología , Postura , Terapia por Ejercicio
6.
Biol Sport ; 39(3): 571-577, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35959333

RESUMEN

The aim of the current study is to determine how the level of state and trait anxiety differs between youth athletes of different performance levels and furthermore whether there are correlations between performance levels and psychomotor variables in the selected tasks. A sample of 97 boys, aged 11-12 years, practising soccer represented two groups: A - high performance level and B - lower performance level. Participants completed a state and trait anxiety inventory and performed selected psychomotor tests. The analyses demonstrated that the higher the levels of anxiety were, the shorter was the response time and more accurate were the responses in selected psychomotor tests. For the whole group, r = -0.224, p < 0.05, and for group B, r = -0.333, p < 0.05. Moreover, the findings showed a moderator effect of level (group A vs B) on reaction time, which was almost significant in state anxiety and significant in trait anxiety. For group B, trait anxiety was negatively related to reaction time (b = -0.002, SE = 0.001, t = -2.93, p = .004, 95% CI [-0.004, -0.001]). This means that the higher the trait anxiety was, the shorter was the reaction time in group B, but there was no significant effect in group A. The results of the study confirmed the negative correlation between the trait and state anxiety and reaction time. The higher the anxiety was, the shorter was the response time of child soccer players. Future research should determine whether athletes' performance levels do affect performance under stress and replicate the study with different samples such as girls and different sport disciplines.

7.
Acta Bioeng Biomech ; 22(3): 69-75, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33518728

RESUMEN

PURPOSE: The purpose of the study was presentation of modern bioengineering technology in order to help people with severe disabilities. METHODS: Bioengineering industry can offer severely disabled people several devices in order to enable them to take part in the competition different than Paralympics. The first international competition for people with disabilities supported by modern assistive technology, such as sensors, motors, displays were allowed to compete in Cybathlon held in Zürich in 2016. About 70 athletes and their teams from 25 countries appeared at the event. RESULTS: There were six disciplines (races): 1) Powered Arms (Upper Extremities) Prostheses Race, 2) Powered Legs (Lower Extremities) Prostheses Race, 3) Powered Wheelchair Race, 4) Powered Exoskeleton Race, 5) Functional Electrical Stimulation Bike Race, 6) Brain-Computer Interface Race. About a quarter of the teams represented industry and the rest represented university laboratories. CONCLUSIONS: The competition was a success. The organisers have decided for it to be organized every four years, just like the Olympic Games for able bodied competitors. The main inventor of the event professor Robert Riener from Zürich Polytechnic (ETHZ) said assistive technology should: a) be user-friendly b) to function well, c) be affordable, d) to be used within the barrier-free environment.


Asunto(s)
Personas con Discapacidad , Tecnología , Miembros Artificiales , Ciclismo , Interfaces Cerebro-Computador , Estimulación Eléctrica , Humanos , Extremidad Inferior/fisiología , Deportes , Suiza , Silla de Ruedas
8.
Genes (Basel) ; 10(6)2019 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-31208055

RESUMEN

Iron is essential for physical activity due to its role in energy production pathways and oxygen transportation via hemoglobin and myoglobin. Changes in iron-related biochemical parameters after physical exercise in athletes are of substantial research interest, but molecular mechanisms such as gene expression are still rarely tested in sports. In this paper, we evaluated the mRNA levels of genes related to iron metabolism (PCBP1, PCBP2, FTL, FTH, and TFRC) in leukocytes of 24 amateur runners at four time points: before, immediately after, 3 h after, and 24 h after a marathon. We measured blood morphology as well as serum concentrations of iron, ferritin, and C-reactive protein (CRP). Our results showed significant changes in gene expression (except for TFRC), serum iron, CRP, and morphology after the marathon. However, the alterations in mRNA and protein levels occurred at different time points (immediately and 3 h post-run, respectively). The levels of circulating ferritin remained stable, whereas the number of transcripts in leukocytes differed significantly. We also showed that running pace might influence mRNA expression. Our results indicated that changes in the mRNA of genes involved in iron metabolism occurred independently of serum iron and ferritin concentrations.


Asunto(s)
Atletas , Ferritinas/sangre , Hierro/sangre , Carrera/fisiología , Adulto , Apoferritinas/sangre , Proteína C-Reactiva/metabolismo , Proteínas de Unión al ADN/sangre , Expresión Génica/genética , Hemoglobinas/metabolismo , Humanos , Leucocitos/metabolismo , Masculino , Persona de Mediana Edad , Mioglobina/sangre , Oxidorreductasas/sangre , ARN Mensajero/sangre , Proteínas de Unión al ARN/sangre
9.
Biol Sport ; 36(4): 357-363, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31938007

RESUMEN

The study aims were to determine the distance covered by goalkeepers during matches in the context of game duration and result, to identify the area of their most frequent activity, and to assess goalkeepers' involvement in games finished with a win, draw, or loss. The investigation was based on two innovative tools: the goalkeeper's activity index (GAI) and an analysis of 5-min periods. A video tracking system was used to monitor 17 goalkeepers from Polish National League teams during 15 matches. The GAI was applied to assess their involvement in the game. Elite goalkeepers covered 72.7%, 25.8%, and 2.5% of the distance during the game by walking/jogging, running, and sprinting, respectively. The distances covered in lost, won, and drawn matches turned out similar (mean ± SD: 4800 ± 906 m, 4696 ± 1033 m, and 4660 ± 754 m, respectively). There were no significant differences between the distances covered in the first and second halves. The area of most frequent activity was the middle sector of the penalty area between the goal and penalty area lines. ANOVA results showed that in drawn matches, goalkeepers' activity significantly differed in mean values of the GAI in comparison with that in won and lost games (p = 0.034, p = 0.039, respectively). It was noted that goalkeepers tended to intervene more often in games where their team was winning rather than in those with a losing result. Their direct involvement in defending the goal was the lowest in drawn games.

10.
Front Psychol ; 9: 980, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30008684

RESUMEN

Background: Participation in extreme endurance sports is becoming an increasingly popular activity, and thus more and more people are getting involved in it. Taking part in a 100 km run is associated with great physiological and psychological stress, which can affect one's mood state. Thus, the goal of this study was to determine if personality, experience, and motives for participation are related to a runner's mood and its changes as well as to investigate whether vitamin D3 supplementation influences mood 12 h before and 12 h after the run. Method: The study group consisted of 20 experienced marathon and ultramarathon runners taking part in a 100 km track run. All participants were males aged between 31 and 50 (M = 40.75, SD = 7.15). The group was divided in two equal subgroups: the placebo group and the group supplemented with vitamin D3. Personality traits were assessed using the Polish version of Eysenck's EPQ-R 106 and mood states were measured twice (12 h before and after the run) using the Polish version of the UMACL by Mathews, Chamberlain, and Jones. Motives for participation in ultramarathons were measured with the IPAO by Lipowski and Zaleski. Results: Levels of vitamin D3 correlated very strongly with energetic arousal (EA) (rs = 0.80; p < 0.05) and strongly hedonic tone (HT) (rs = 0.74; p < 0.05) 12 h before the run. There were no significant correlations between levels of vitamin D3 and mood states after the run. Moreover, extraversion correlated moderately with tense arousal (TA) (rs = -0.48; p < 0.05) and EA (rs = 0.47; p < 0.05) while neuroticism correlated moderately with TA (rs = 0.53; p < 0.05) and HT (rs = -0.57; p < 0.05). Conclusion: Both personality and vitamin D3 supplementation are related to runners' pre-run mood. These effects are nullified when it comes to post-run mood states.

11.
Acta Bioeng Biomech ; 19(1): 69-79, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28552919

RESUMEN

PURPOSE: This paper aims at the description and comparison of methods of topographic analysis of racing courses at all disciplines of alpine skiing sports for the purposes of obtaining: terrain geomorphology (snowless and with snow), course geometry, and competitors' runs. METHODS: The review presents specific methods and instruments according to the order of their historical appearance as follows: (1) azimuth method with the use of a compass, tape and goniometer instruments; (2) optical method with geodetic theodolite, laser and photocells; (3) triangulation method with the aid of a tape and goniometer; (4) image method with the use of video cameras; (5) differential global positioning system and carrier phase global positioning system methods. RESULTS: Described methods were used at homologation procedure, at training sessions, during competitions of local level and during International Ski Federation World Championships or World Cups. Some methods were used together. CONCLUSIONS: In order to provide detailed data on course setting and skiers' running it is recommended to analyse course geometry and kinematics data of competitors' running for all important competitions.


Asunto(s)
Aceleración , Ecosistema , Sistemas de Información Geográfica , Imagenología Tridimensional/métodos , Tecnología de Sensores Remotos , Esquí/fisiología , Humanos
12.
Clin Interv Aging ; 11: 1763-1771, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27942207

RESUMEN

BACKGROUND: Several studies have demonstrated the positive effects of physical activity on skeletal muscle mass and muscle strength in women with osteoporosis. However, the impact of Nordic walking training on sarcopenia-related parameters in women with low bone mass remains unknown. Therefore, the purpose of this study was to evaluate the impact of 12 weeks of Nordic walking training on skeletal muscle index, muscle strength, functional mobility, and functional performance in women with low bone mass. MATERIALS AND METHODS: The participants were 45 women, aged 63-79 years, with osteopenia or osteoporosis. The subjects were randomly assigned either to an experimental group (12 weeks of Nordic walking training, three times a week) or to a control group. Skeletal muscle mass and other body composition factors were measured with octapolar bioimpedance InBody 720 analyser. Knee extensor and flexor isometric muscle strength were measured using Biodex System 4 Pro™ dynamometers. This study also used a SAEHAN Digital Hand Dynamometer to measure handgrip muscle strength. The timed up-and-go test was used to measure functional mobility, and the 6-minute walk test was used to measure functional performance. RESULTS: Short-term Nordic walking training induced a significant increase in skeletal muscle mass (P=0.007), skeletal muscle index (P=0.007), strength index of the knee extensor (P=0.016), flexor (P<0.001), functional mobility (P<0.001), and functional performance (P<0.001) and a significant decrease in body mass (P=0<006), body mass index (P<0.001), and percent body fat (P<0.001) in participants. Regarding handgrip muscle strength, no improvement was registered (P=0.315). No significant changes in any of the analyzed parameters were observed in the control group. CONCLUSION: Overall, short-term Nordic walking training induces positive changes in knee muscle strength and functional performance in women with low bone mass. This finding could be applied in clinical practice for intervention programs in women with osteopenia and osteoporosis.


Asunto(s)
Fuerza Muscular/fisiología , Músculo Esquelético/fisiología , Osteoporosis Posmenopáusica/terapia , Caminata/fisiología , Anciano , Composición Corporal/fisiología , Índice de Masa Corporal , Densidad Ósea , Enfermedades Óseas Metabólicas/fisiopatología , Enfermedades Óseas Metabólicas/terapia , Ejercicio Físico , Femenino , Fuerza de la Mano , Humanos , Articulación de la Rodilla/fisiopatología , Persona de Mediana Edad , Osteoporosis Posmenopáusica/fisiopatología , Sarcopenia/fisiopatología , Sarcopenia/terapia
13.
J Hum Kinet ; 53: 33-40, 2016 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-28149408

RESUMEN

The aim of the study was to define the relationship between maximal power of lower limbs, the biomechanics of the forward handspring vault and the score received during a gymnastics competition. The research involved 42 gymnasts aged 9-11 years competing in the Poland's Junior Championships. The study consisted of three stages: first -estimating the level of indicators of maximal power of lower limbs tested on a force plate during the countermovement jump; second - estimating the level of biomechanical indicators of the front handspring vault. For both mentioned groups of indicators and the score received by gymnasts during the vault, linear correlation analyses were made. The last stage consisted of conducting multiple regression analysis in order to predict the performance level of the front handspring vault. Results showed a positive correlation (0.401, p < 0.05) of lower limbs' maximal power (1400 ± 502 W) with the judges' score for the front handstand vault (13.38 ± 1.02 points). However, the highest significant (p < 0.001) correlation with the judges' score was revealed in the angle of the hip joint in the second phase of the flight (196.00 ± 16.64°) and the contact time of hands with the vault surface (0.264 ± 0.118 s), where correlation coefficients were: -0.671 and -0.634, respectively. In conclusion, the angles of the hip joint in the second phase of the flight and when the hands touched the vault surface proved to be the most important indicators for the received score.

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