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1.
J Strength Cond Res ; 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38814694

RESUMO

ABSTRACT: Bartolomei, S, Francesco, L, Latini, D, and Hoffman, JR. Autoregulation does not provide additional benefits to a mixed session periodized resistance training program in trained men. J Strength Cond Res XX(X): 000-000, 2024-The aim of this investigation was to study how autoregulation impacted training volume, performance, and muscle size on a 10-week mixed session periodized (MSP) resistance training program, characterized by the inclusion of different training foci in each session. Twenty-four resistance trained men were assigned to an autoregulated mixed session periodized (AMSP group; n = 13; age = 26.2 ± 4.9 y; body mass = 82.0 ± 8.7 kg; height = 176.8 ± 6.0 cm) or into an MSP (n = 11; age = 24.0 ± 2.6; body mass = 81.3 ± 10.5 kg; height = 174.0 ± 5.4 cm) group. Subjects in both groups trained 5 days per week for 10 weeks and performed the same exercises. The difference between the groups consisted in the use of a perceived recovery-based scale to adjust the individual training volume in the AMSP program. Maximal strength (bench press and squat 1 repetition maximum), power (bench press throw and countermovement jump), and muscle architecture (muscle thickness [MT] of biceps brachii, trapezius, vastus lateralis and vastus medialis) were collected before and after the 10-week training period. In addition, training volume and session load were calculated for each training session. A higher total training volume (p < 0.001) was seen in AMSP program compared with MSP program, but no differences (p > 0.05) were noted in the average session load. No significant differences between the groups were detected for MT of both upper-body and lower-body muscles (p's > 0.05) and lean body mass (p = 0.681). No significant differences between the groups were detected for any strength or power measurements. Results of this study indicate that a perceived recovery-based AMSP training program was not more effective than an MSP training program for increasing muscle size and performance in resistance trained men.

2.
J Strength Cond Res ; 38(7): 1200-1205, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38551927

RESUMO

ABSTRACT: Bartolomei, S, Caroli, E, Coloretti, V, Rosaci, G, Cortesi, M, and Coratella, G. Flat-back vs. arched-back bench press: Examining the different techniques performed by power athletes. J Strength Cond Res 38(7): 1200-1205, 2024-The International Powerlifting Federation recently changed the regulations concerning the bench press (BP) technique, not allowing an accentuated dorsal arch anymore. We investigated the difference between the flat-back vs. arched-back BP performed by competitive powerlifters as concerns the following parameters: (a) 1 repetition maximum (1RM) and barbell displacement; (b) mean and peak barbell velocity and power, and (c) the excitation of the prime movers. Fifteen highly resistance trained individuals (BP 1RM/body mass ratio: 1.38 ± 0.18) performed the flat-back and arched-back BP at their 50, 70, and 90% of the respective 1RM and performed each lift with the intent to maximally accelerate the barbell. Barbell displacement and velocity, power, and the excitation of the upper and lower pectoralis and triceps brachii were assessed. The 1RM was greater with the arched-back BP (+4.2 Kg, 95% confidence intervals + 0.0/+8.4, effect size [ES]: 0.22), whereas the barbell displacement was greater with the flat-back BP for all loads (ES from 0.40 to 0.61). Greater mean (+0.052 m·s -1 , 0.016/0.088, ES: 0.42) and peak barbell velocity (+0.068 m·s -1 , +0.026/0.110, ES: 0.27) were observed in the flat-back BP, whereas power did not differ. The excitation of upper and lower pectoralis was similar, while an overall trend for an increased activation of triceps brachii was noted in the arched-back vs. flat-back BP. Interestingly, no between-load difference in the excitation of upper and lower pectoralis was observed ( p > 0.05). Depending on the training purposes, both flat-back and arched-back BP may be used. The present outcomes may assist practitioners and competitive powerlifters to inform training session.


Assuntos
Força Muscular , Levantamento de Peso , Humanos , Levantamento de Peso/fisiologia , Força Muscular/fisiologia , Masculino , Adulto Jovem , Adulto , Músculo Esquelético/fisiologia , Treinamento Resistido/métodos , Atletas , Eletromiografia
3.
J Strength Cond Res ; 37(1): 68-73, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-35900802

RESUMO

ABSTRACT: Bartolomei, S, De Luca, R, and Marcora, SM. May a nonlocalized postactivation performance enhancement exist between the upper and lower body in trained men? J Strength Cond Res 37(1): 68-73, 2023-The aim of this study was to establish whether a resistance exercise for the upper body may generate a postactivation performance enhancement (PAPE) in the lower body. Thirteen resistance-trained men (age = 26.4 ± 3.3 years, body mass = 76.9 ± 6.3 kg, and height = 177.6 ± 5.2 cm) participated in the present investigation and were tested for upper-body and lower-body power (bench press throw and countermovement jump power [CMJP] tests). Subjects were also tested for maximum force and electromyographic (EMG) activation of quadriceps muscles while performing an isometric leg extension. All assessments were performed before and 8 minutes after a high-intensity (HI: 5 sets of 1 rep at 90% of 1 repetition maximum [1RM]) bench press protocol, a high-power protocol (POW: 5 sets of 1 rep at 30% of 1RM with maximum explosive intent), and a control trial (CON). Subjects performed all trials in a randomized order and on different days. A significant trial × time interaction was detected for CMJP ( p = 0.049). This parameter was significantly increased following the HI protocol only ( p = 0.024). A significant interaction was also noted for EMG with a significant improvement following the HI protocol ( p = 0.032) and a significant decrease following the POW protocol ( p = 0.020). No other significant effects were detected ( p > 0.05). The results of this investigation indicate that a HI bench press protocol may produce a PAPE in the lower-body power and increase the neuromuscular activation of leg extensor muscles. The POW bench press protocol did not show any positive effects on lower-body performance. Athletes and practitioners may take advantage from the inclusion of upper-body HI resistance exercises throughout complex resistance workouts to improve lower-body power output.


Assuntos
Força Muscular , Treinamento Resistido , Masculino , Humanos , Adulto Jovem , Adulto , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Atletas , Teste de Esforço/métodos , Exercício Físico , Treinamento Resistido/métodos
4.
J Strength Cond Res ; 37(3): 537-545, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36727999

RESUMO

ABSTRACT: Bartolomei, S, Zaniboni, F, Verzieri, N, and Hoffman, JR. New perspectives in resistance training periodization: mixed session vs. block periodized programs in trained men. J Strength Cond Res 37(3): 537-545, 2023-The purpose of this investigation was to compare the effects of 2 different periodized resistance training programs on maximal strength, power, and muscle architecture, in trained individuals. Twenty-two resistance-trained men were randomly assigned to either a mixed session training group (MSP; n = 11; age = 23.7 ± 2.6 years; body mass = 80.5 ± 9.8 kg; height = 175.5 ± 6.1 cm) or a block periodization group (BP; n = 11; age = 25.7 ± 4.6 years; body mass = 81.1 ± 10.7 kg; height = 176.8 ± 8.4 cm). Both training programs were 10 weeks in duration and were equated in volume. Each training session of the MSP focused on power, maximal strength, and hypertrophy, whereas each mesocycle within the BP focused on one of these components. Subjects were assessed for body composition, muscle architecture, maximal strength, and power. In addition, perceived training load, and training volume were calculated. Subjects in MSP experienced greater improvements in fat free mass ( p = 0.021), muscle thickness of the pectoralis and vastus lateralis ( p < 0.05), and a greater improvement in 1RM bench press ( p < 0.001; +8.6% in MSP and +2% in BP) than in BP. By contrast, BP resulted in greater improvements in vertical jump ( p = 0.022; +7.2%) compared with MSP (+1.2%). No significant differences were noted between the groups for perceived training load ( p = 0.362) nor training volume ( p = 0.169). Results of this study indicated that in a 10-week training study, MSP may enhance muscle hypertrophy and maximal strength to a greater extent than BP, with the same training volume and perceived training load. However, BP may be more effective for vertical jump improvement.


Assuntos
Treinamento Resistido , Masculino , Humanos , Adulto Jovem , Adulto , Treinamento Resistido/métodos , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Composição Corporal , Hipertrofia
5.
Sensors (Basel) ; 22(23)2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36501840

RESUMO

The aim of the study was to compare the recovery response and muscle oxygenation of a blood-flow restriction resistance exercise (BFR) session with high [HP: 80% of the arterial occlusion pressure (AOP)] and low cuff pressure (LP: 40% of AOP). Both exercise sessions included 4 sets to failure at the barbell preacher curl exercise. Twelve resistance trained men (27.4 ± 5.0 years; 83.5 ± 11.6 kg; 176.6 ± 7.0 cm) performed each protocol in a counterbalanced, randomized order. Maximal isometric force, muscle morphology and muscle soreness of the biceps brachii muscle were assessed at baseline, 15-min, 60-min and 24-h post each testing session. In addition, muscle oxygen saturation (SmO2) was assessed during each training session. A lower number of repetitions (p = 0.013) was detected in HP compared to LP. A lower SmO2 (p < 0.001) was detected in the recovery time between the sets in HP (mean: 47.6 ± 15.7%) compared to LP (mean: 68.9 ± 7.2%). No differences between the two trials (p > 0.05) were noted for isometric force, muscle architecture and soreness at any timepoint. Results indicate that, despite a high cuff pressure may induce a more hypoxic condition compared to a lower cuff pressure, recovery responses may not be affected.


Assuntos
Treinamento Resistido , Humanos , Masculino , Braço , Músculo Esquelético/fisiologia , Saturação de Oxigênio , Fluxo Sanguíneo Regional/fisiologia , Treinamento Resistido/métodos , Adulto Jovem , Adulto
6.
Sensors (Basel) ; 22(4)2022 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-35214321

RESUMO

Quantitative evaluation of synergic action among the different body segments is fundamental to swimming performance. The aim of the present study was to develop an easy-to-use tool for stroke-by-stroke evaluation of a swimmer's integrated timing of stroking, kicking, and breathing. Twelve swimmers were evaluated during one trial of 100 m front-crawl swimming at self-selected speed. Five three-axial inertial sensors were mounted on the head, wrists, and ankles. Algorithms for the wrist entry into the water, the lower limb beat during the downward action, and the exit/entry of the face from/into the water were developed. Temporal events identified by video-based technique, using one sagittal moving camera, were assumed as the gold standard. The performance was evaluated in terms of the root-mean-square error, 90th percentile of absolute error, coefficient of variation, Bland-Altman plots, and correlation analysis. Results of all temporal events showed high agreement with the gold standard, confirmed by a root-mean-square error of less than 0.05 s for absolute temporal parameters and less than 0.7% for the percentages of the stroke cycle duration, and with correlation coefficients higher than 0.856. The protocol proposed was not only accurate and reliable, but also user-friendly and as unobtrusive as possible for the swimmer, allowing a stroke-by-stroke analysis during the training session.


Assuntos
Natação , Dispositivos Eletrônicos Vestíveis , Fenômenos Biomecânicos , Respiração , Punho
7.
J Strength Cond Res ; 36(7): 1909-1915, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32956264

RESUMO

ABSTRACT: Bartolomei, S, Nigro, F, D'Amico, A, Cortesi, M, and Di Michele, R. Mud pack with menthol and Arnica montana accelerates recovery following a high-volume resistance training session for lower body in trained men. J Strength Cond Res 36(7): 1909-1915, 2022-The aim of this study was to compare the effects of a mud pack, containing menthol and Arnica montana, on the recovery responses following a high-volume resistance protocol. Ten resistance-trained men (mean ± SD: age = 25.3 ± 6.1 years; body mass = 79.1 ± 10.6 kg; height = 178.9 ± 7.5 cm) performed a high-volume resistance workout for lower body squat and leg extension, (5 sets of 10 reps at 70% of one repetition maximum for both exercises). All the subject used mud (MUD) or a placebo (PL) in randomized counterbalanced crossover design. MUD or PL were applied 4 times: 3, 19, 27, and 45 hours after the workout, on the skin surface above the quadriceps muscle of both legs. Muscle performance (countermovement jump power [CMJP], isokinetic leg press at 75 cm·s-1 and 25 cm·s-1 [ISOK75 and ISOK25, respectively], isometric squat [ISQ]), and morphology (muscle thickness of vastus lateralis [VLMT]), were measured before exercise (baseline [BL]), and 15 minutes (15P), 24 hours (24P), and 48 hours (48P) postexercise. In addition, muscle soreness was assessed at the same time points using a visual analog scale (VAS). No significant interactions (p > 0.05) between the trials were detected for CMJP, ISOK75, ISQ, and VLMT. A significant interaction between trials was noted for ISOK25 (p = 0.022) and for VAS (p = 0.001). ISOK25 was significantly (p < 0.01) reduced from BL at 15P, 24P and 48P in PL, whereas changes were significant (p < 0.05) at 15P and 24P only in MUD. The present findings indicate that MUD may enhance the recovery rate of strength and reduce muscle soreness after high-volume exercise. Muscle morphology do not seem to be influenced by mud packs.


Assuntos
Arnica , Peloterapia , Treinamento Resistido , Adulto , Humanos , Masculino , Mentol , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Mialgia , Treinamento Resistido/métodos , Adulto Jovem
8.
J Strength Cond Res ; 36(2): 299-303, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31895282

RESUMO

ABSTRACT: Bartolomei, S, Rovai, C, Lanzoni, IM, and di Michele, R. Relationships between muscle architecture, deadlift performance, and maximal isometric force produced at the midthigh and midshin pull in resistance-trained individuals. J Strength Cond Res 36(2): 299-303, 2022-The aim of this study was to investigate the relationships between muscle architecture, lower-body power, and maximal isometric force produced at midthigh pull (MTP), and at midshin pull (MSP). Twenty experienced resistance-trained men (age = 25.5 ± 3.2 years; body mass = 86.9 ± 12.4 kg; body height = 178.0 ± 5.3 cm) were tested for deadlift 1 repetition maximum (1RM), countermovement jump (CMJ), peak force (PF), and rate of force development (pRFD20) produced at isometric MTP and isometric MSP. Subjects were also assessed for architecture of vastus lateralis (VL). Physiological muscle thickness, pennation angle, and fascicle length (FL) were measured. Pearson's correlation coefficients were calculated to assess the relationships between variables. In addition, differences between MTP and MSP were assessed using paired-sample t-tests. A significant (p < 0.05) difference was detected on the correlation between deadlift 1RM and MSP (r = 0.78; p < 0.001) compared with MTP (r = 0.55; p = 0.012). Moderate correlations were observed between MSP PF and VLFL (r = 0.55; p = 0.011). Midshin pull pRFD20 was the only parameter significantly correlated with CMJ (r = 0.50; p = 0.048). Significantly higher PF and pRFD20 were recorded in MTP compared with MSP (p = 0.007 and p = 0.003, respectively). The present results show that force produced from the floor position may be more important than force produced from a position that mimics the second pull of the clean for deadlift and vertical jump performances. Coaches and scientific investigators should consider using MSP to assess isometric PF using a test correlated with both muscle architecture and dynamic performances.


Assuntos
Contração Isométrica , Força Muscular , Adulto , Humanos , Masculino , Músculo Esquelético , Músculo Quadríceps/diagnóstico por imagem , Adulto Jovem
9.
Sensors (Basel) ; 21(2)2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33418870

RESUMO

The present study aimed to explore the variability of the arm-stroke temporal descriptors between and within laps during middle-distance swimming event using IMMUs. Eight male swimmers performed a 200-m maximum front-crawl in which the inter-lap and intra-lap variability of velocity, stroke rate, stroke-phases duration and arm-coordination index were measured through five units of IMMU. An algorithm computes the 3D coordinates of the wrist by means the IMMU orientation and the kinematic chain of upper arm biomechanical model, and it recognizes the start events of the four arm-stroke phases. Velocity and stroke rate had a mean value of 1.47 ± 0.10 m·s-1 and 32.94 ± 4.84 cycles·min-1, respectively, and a significant decrease along the 200-m (p < 0.001; η2 = 0.80 and 0.47). The end of each lap showed significantly lower stroke rate compared to the start and the middle segment (p < 0.05; η2 = 0.55). No other significant inter-lap and intra-lap differences were detected. The two main findings are: (i) IMMUs technology can be an effective solution to continuously monitor the temporal descriptors during the swimming trial; (ii) swimmers are able to keep stable their temporal technique descriptors in a middle-distance event, despite the decrease of velocity and stroke rate.


Assuntos
Natação , Punho , Algoritmos , Fenômenos Biomecânicos , Masculino
10.
J Strength Cond Res ; 35(Suppl 1): S180-S187, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30844990

RESUMO

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.


Assuntos
Treinamento Resistido , Adulto , Exercício Físico , Humanos , Masculino , Força Muscular , Músculo Esquelético , Levantamento de Peso , Adulto Jovem
11.
J Strength Cond Res ; 35(6): 1520-1526, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32168178

RESUMO

ABSTRACT: Bartolomei, S, Nigro, F, Malagoli Lanzoni, I, Masina, F, Di Michele, R, and Hoffman, JR. A comparison between total body and split routine resistance training programs in trained men. J Strength Cond Res 35(6): 1520-1526, 2021-The purpose of the present investigation was to compare the effects of total body (TB) versus split routine (SR) resistance training workouts on maximal strength and muscle hypertrophy in trained men. Twenty-one resistance-trained men were randomly assigned to either a TB (TB: age = 24.1 ± 4.4 years; body mass = 78.7 ± 11.3 kg; body height = 177.0 ± 3.9 cm) or the SR group (SR: age = 24.9 ± 4.2 years; body mass = 79.2 ± 9.5 kg; body height = 175.2 ± 6.0 cm). Both groups performed a 10-week resistance training program. Isokinetic bench press at 75 and 25 cm·s-1 (ISOK75 and ISOK25, respectively), isometric bench press (ISOBP), isometric squat (ISOSQ), and one repetition maximum BP and SQ assessments were performed before and after training. Muscle thickness of the pectoralis major (PECMT), superior part of trapezius (TRAPMT), and vastus lateralis (VLMT) muscles was also evaluated at the same timepoints using ultrasonography. Improvements were observed in both groups for all strength assessments and muscle thicknesses. Only changes in ISOK25 were significantly (p = 0.015) greater in TB than in SR, while significantly greater (p = 0.037) changes in VLMT were detected in SR compared with TB. Results indicated that a TB training paradigm may be more appropriate for maximal strength improvement, while an SR training protocol may be more optimal in stimulating muscle growth in experienced, resistance-trained men.


Assuntos
Treinamento Resistido , Adulto , Humanos , Masculino , Força Muscular , Músculo Esquelético/diagnóstico por imagem , Músculo Quadríceps , Ultrassonografia , Adulto Jovem
12.
J Strength Cond Res ; 33(11): 3123-3128, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29470363

RESUMO

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.


Assuntos
Aptidão , Desempenho Atlético , Hóquei/fisiologia , Aptidão Física/fisiologia , Adulto , Composição Corporal , Estatura , Força da Mão , Humanos , Itália , Masculino , Adulto Jovem
13.
J Sports Sci Med ; 18(3): 438-447, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31427865

RESUMO

Monitoring the upper arm propulsion is a crucial task for swimmer performance. The swimmer indeed can produce displacement of the body by modulating the upper limb kinematics. The present study proposes an approach for automatically recognize all stroke phases through three-dimensional (3D) wrist's trajectory estimated using inertial devices. Inertial data of 14 national-level male swimmer were collected while they performed 25 m front-crawl trial at intensity range from 75% to 100% of their 25 m maximal velocity. The 3D coordinates of the wrist were computed using the inertial sensors orientation and considering the kinematic chain of the upper arm biomechanical model. An algorithm that automatically estimates the duration of entry, pull, push, and recovery phases result from the 3D wrist's trajectory was tested using the bi-dimensional (2D) video-based systems as temporal reference system. A very large correlation (r = 0.87), low bias (0.8%), and reasonable Root Mean Square error (2.9%) for the stroke phases duration were observed using inertial devices versus 2D video-based system methods. The 95% limits of agreement (LoA) for each stroke phase duration were always lower than 7.7% of cycle duration. The mean values of entry, pull, push and recovery phases duration in percentage of the complete cycle detected using 3D wrist's trajectory using inertial devices were 34.7 (± 6.8)%, 22.4 (± 5.8)%, 14.2 (± 4.4)%, 28.4 (± 4.5)%. The swimmer's velocity and arm coordination model do not affect the performance of the algorithm in stroke phases detection. The 3D wrist trajectory can be used for an accurate and complete identification of the stroke phases in front crawl using inertial sensors. Results indicated the inertial sensor device technology as a viable option for swimming arm-stroke phase assessment.


Assuntos
Acelerometria/instrumentação , Braço/fisiologia , Destreza Motora/fisiologia , Natação/fisiologia , Algoritmos , Fenômenos Biomecânicos , Humanos , Masculino , Reprodutibilidade dos Testes , Estudos de Tempo e Movimento , Gravação em Vídeo , Dispositivos Eletrônicos Vestíveis , Punho , Adulto Jovem
14.
J Sports Sci ; 36(23): 2637-2643, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29578375

RESUMO

The aim of the present study was to compare the biomechanical characteristics of the table tennis top spin shot when played cross-court (CC) or long-line (LL) in competitive table tennis players. Seven national level players respectively completed 10 long-line and 10 cross-court top spin shots responding to a standard ball machine. A stereophotogrammetric system was used to track body segments while executing the motion. Significantly more flexed right knee and elbow angles were measured at the moment of maximum velocity of the racket (MMV) in LL. In addition, significantly greater angles between the feet and the table and between the shoulders and the table at the MMV, indicated more pronounced rotation angles of the lower upper and upper-body in LL compared to CC with respect to the table. A higher inclination of the racket at the MMV was found in LL. The elbow flexion and the racket inclination may be associated to the direction of the shot. The present findings show that kinematic differences exist between the LL and the CC topspin forehand in competitive table tennis players. Coaches should be aware of these differences to adopt the optimal teaching strategies and to reproduce proper joint angles during training.


Assuntos
Desempenho Atlético , Fenômenos Biomecânicos , Tênis , Adulto , Atletas , Cotovelo , Humanos , Joelho , Masculino , Amplitude de Movimento Articular , Rotação , Ombro , Torque , Adulto Jovem
15.
J Strength Cond Res ; 32(1): 13-18, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29257792

RESUMO

Bartolomei, S, Hoffman, JR, Stout, JR, and Merni, F. Effect of lower-body resistance training on upper-body strength adaptation in trained men. J Strength Cond Res 32(1): 13-18, 2018-The aim of this study was to examine the effect of 2 different lower-body strength training schemes on upper-body adaptations to resistance training. Twenty resistance-trained men (4.25 ± 1.6 years of experience) were randomly assigned to either a high intensity (HI; n = 9; age = 24.9 ± 2.9 years; body mass = 88.7 ± 17.2 kg; height = 177.0 ± 5.6 cm) or a mixed high volume and HI resistance training program (MP; n = 11; age = 26.0 ± 4.7 years; body mass = 82.8 ± 9.1 kg; height = 177.54 ± 5.9 cm). High-intensity group followed a HI training for both upper and lower body (4-5 reps at 88%-90% of 1 repetition maximum (1RM)), whereas the MP group performed high-volume training sessions focused on muscle hypertrophy for lower body (10-12 reps at 65%-70% of 1-RM) and a HI protocol for the upper body. Maximal strength and power testing occurred before and after the 6-week training program. Analysis of covariance was used to compare performance measures between the groups. Greater increases in MP groups compared with HI groups were observed for bench press 1RM (p = 0.007), bench press power at 50% of 1RM (p = 0.011), and for arm muscle area (p = 0.046). Significant difference between the 2 groups at posttest were also observed for fat mass (p = 0.009). Results indicated that training programs focused on lower-body muscle hypertrophy and maximal strength for upper body can stimulate greater strength and power gains in the upper body compared with HI resistance training programs for both the upper and lower body.


Assuntos
Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Treinamento Resistido/métodos , Adaptação Fisiológica , Adulto , Humanos , Masculino , Adulto Jovem
16.
J Strength Cond Res ; 32(1): 244-247, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28922211

RESUMO

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.


Assuntos
Amônia/administração & dosagem , Estimulantes do Sistema Nervoso Central/administração & dosagem , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Adulto , Atletas , Estudos Cross-Over , Humanos , Contração Isométrica/fisiologia , Masculino , Movimento , Treinamento Resistido , Adulto Jovem
17.
J Strength Cond Res ; 32(6): 1503-1510, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29528954

RESUMO

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.


Assuntos
Teste de Esforço/métodos , Força Muscular , Treinamento Resistido , Levantamento de Peso/fisiologia , Adulto , Área Sob a Curva , Humanos , Masculino , Músculo Esquelético/fisiologia , Distribuição Aleatória , Adulto Jovem
18.
Eur J Appl Physiol ; 117(7): 1287-1298, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28447186

RESUMO

PURPOSE: The purpose of this study was to compare the physiological responses of a high-volume (HV; 8 sets of 10 repetitions) versus high-intensity (HI; 8 sets of 3 repetitions) exercise protocol in resistance-trained men. METHODS: Twelve men (24.5 ± 4.2 years; 82.3 ± 8.4 kg; 175.2 ± 5.5 cm) with 6.3 ± 3.4 years of resistance training experience performed each protocol in a counterbalanced, randomized order. Performance [counter movement jump peak power (CMJP), isokinetic (ISOK) and isometric leg extension (MVIC), isometric mid-thigh pull (IMTP), and isometric squat (ISQ)] and muscle morphological [cross-sectional area (CSA) of vastus lateralis] assessments were performed at baseline (BL), 30-min (P-30 min), 24-h (P-24 h), 48-h (P-48 h), and 72-h (P-72 h) post-exercise for each testing session. In addition, endocrine (testosterone and cortisol), inflammatory [interleukin-6 (IL-6) and C-reactive protein (CRP)], and markers of muscle damage [creatine kinase (CK), lactate dehydrogenase (LDH), and myoglobin (Mb)] were assessed at the same time points. RESULTS: Significantly greater reductions in CMJP (p < 0.001), and peak torque during both ISOK (p = 0.003) and MVIC (p = 0.008) at P-30 min were detected in HV compared to HI protocol. MVIC was still impaired at P-72 h following the HV protocol, while no differences were noted following HI. Markers of muscle damage (LDH, CK, and Mb) were significantly elevated following both HV and HI (p < 0.05), while cortisol and IL-6 concentrations were significantly elevated at P-30 min following HV only (p < 0.001 and p < 0.05, respectively). CONCLUSIONS: Results indicate that high-volume resistance exercise results in greater performance deficits, and a greater extent of muscle damage, than a bout of high-intensity resistance exercise.


Assuntos
Treinamento Intervalado de Alta Intensidade/efeitos adversos , Músculo Esquelético/fisiologia , Mialgia/reabilitação , Treinamento Resistido/efeitos adversos , Adulto , Proteína C-Reativa/metabolismo , Creatina Quinase/sangue , Humanos , Hidrocortisona/sangue , Interleucina-6/sangue , Contração Isométrica , L-Lactato Desidrogenase/sangue , Perna (Membro)/fisiologia , Masculino , Músculo Esquelético/metabolismo , Mialgia/etiologia , Mialgia/fisiopatologia , Mioglobina/metabolismo , Recuperação de Função Fisiológica , Testosterona/sangue
19.
J Sports Sci ; 35(13): 1270-1278, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27540875

RESUMO

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.


Assuntos
Desempenho Atlético/fisiologia , Comportamento Competitivo/fisiologia , Corrida/fisiologia , Atletismo/fisiologia , Aceleração , Adolescente , Adulto , Fenômenos Biomecânicos , Feminino , Humanos , Modelos Lineares , Masculino , Fatores Sexuais , Estudos de Tempo e Movimento , Adulto Jovem
20.
J Strength Cond Res ; 31(5): 1338-1345, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28166187

RESUMO

Wang, R, Hoffman, JR, Sadres, E, Bartolomei, S, Muddle, TWD, Fukuda, DH, and Stout, JR. Evaluating upper-body strength and power from a single test: the ballistic push-up. J Strength Cond Res 31(5): 1338-1345, 2017-The purpose of this study was to examine the reliability of the ballistic push-up (BPU) exercise and to develop a prediction model for both maximal strength (1 repetition maximum [1RM]) in the bench press exercise and upper-body power. Sixty recreationally active men completed a 1RM bench press and 2 BPU assessments in 3 separate testing sessions. Peak and mean force, peak and mean rate of force development, net impulse, peak velocity, flight time, and peak and mean power were determined. Intraclass correlation coefficients were used to examine the reliability of the BPU. Stepwise linear regression was used to develop 1RM bench press and power prediction equations. Intraclass correlation coefficient's ranged from 0.849 to 0.971 for the BPU measurements. Multiple regression analysis provided the following 1RM bench press prediction equation: 1RM = 0.31 × Mean Force - 1.64 × Body Mass + 0.70 (R = 0.837, standard error of the estimate [SEE] = 11 kg); time-based power prediction equation: Peak Power = 11.0 × Body Mass + 2012.3 × Flight Time - 338.0 (R = 0.658, SEE = 150 W), Mean Power = 6.7 × Body Mass + 1004.4 × Flight Time - 224.6 (R = 0.664, SEE = 82 W); and velocity-based power prediction equation: Peak Power = 8.1 × Body Mass + 818.6 × Peak Velocity - 762.0 (R = 0.797, SEE = 115 W); Mean Power = 5.2 × Body Mass + 435.9 × Peak Velocity - 467.7 (R = 0.838, SEE = 57 W). The BPU is a reliable test for both upper-body strength and power. Results indicate that the mean force generated from the BPU can be used to predict 1RM bench press, whereas peak velocity and flight time measured during the BPU can be used to predict upper-body power. These findings support the potential use of the BPU as a valid method to evaluate upper-body strength and power.


Assuntos
Teste de Esforço/métodos , Força Muscular/fisiologia , Levantamento de Peso/fisiologia , Adolescente , Adulto , Índice de Massa Corporal , Humanos , Masculino , Análise de Regressão , Reprodutibilidade dos Testes , Adulto Jovem
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