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Danica Janicijevic and Amador Garcia-Ramos

This systematic review aimed to synthesize the current evidence on the feasibility of volitional reaction time (RT) tests to evaluate the information processing abilities of athletes. Four databases were searched, and, finally, 38 studies exploring the reliability, validity, or sensitivity of RT tests were included. Seven studies explored the reliability, which ranged from poor to excellent, while only three studies explored the validity of RT tests. The most important downside of the majority of the implemented RT tests is their nonspecific nature (i.e., stimulus and response did not resemble the sports actions). Sports scientists should focus on developing RT tests that are specific for each sport and refine the testing procedures to obtain accurate, reproducible, and sensitive measurements of RT.

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Danica Janicijevic, Ivan Jukic, Jonathon Weakley, and Amador García-Ramos

Purpose: To compare the accuracy of nine 1-repetition maximum (1RM) prediction methods during the paused and touch-and-go bench press exercises performed in a Smith machine. Method: A total of 86 men performed 2 identical sessions (incremental loading test until reaching the 1RM followed by a set to failure) in a randomized order during the paused and touch-and-go bench press exercises. Individualized load–velocity relationships were modeled by linear and polynomial regression models considering 4 loads (45%–60%–75%–90% of 1RM) (multiple-point methods) and considering only 2 loads (45%–90% of 1RM) by a linear regression (2-point method). Three minimal velocity thresholds were used: the general velocity of 0.17 m·s−1 (general velocity of the 1RM [V1RM]), the velocity obtained when lifting the 1RM load (individual V1RM), and the velocity obtained during the last repetition of a set to failure. Results: The 1RM prediction methods were generally valid (range: r = .96–.99, standard error of the estimate = 2.8–4.9 kg or 4.6%–8.0% of 1RM). The multiple-point linear method (2.79 [2.29] kg) was more precise than the multiple-point polynomial method (3.54 [3.31] kg; P = .013), but no significant differences were observed when compared with the 2-point method (3.09 [2.66] kg, P = .136). The velocity of the last repetition of a set to failure (3.47 [2.97] kg) was significantly less precise than the individual V1RM (2.91 [2.75] kg, P = .009) and general V1RM (3.00 [2.65] kg, P = .010). Conclusions: Linear regression models and a general minimal velocity threshold of 0.17 m·s−1 should be recommended to obtain a quick and precise estimation of the 1RM during the bench press exercise performed in a Smith machine.

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Amador García-Ramos, Jonathon Weakley, Danica Janicijevic, and Ivan Jukic

Purpose: To explore the effect of several methodological factors on the number of repetitions performed before and after reaching certain velocity loss thresholds (VLTs). Method: Fifteen resistance-trained men (bench press 1-repetition maximum = 1.25 [0.16] kg·kg−1) performed with maximum intent a total of 182 sets (77 short sets [≤12 repetitions] and 105 long sets [>12 repetitions]) leading to failure during the Smith machine bench press exercise. Fifteen percent, 30%, and 45% VLTs were calculated, considering 2 reference repetitions (first and fastest repetitions) and 2 velocity variables (mean velocity [MV] and peak velocity [PV]). Results: The number of repetitions performed before reaching all VLTs were affected by the reference repetition and velocity variable (P ≤ .001). The fastest MV and PV during the short sets (75.3%) and PV during the long sets (72.4%) were predominantly observed during the first repetition, while the fastest MV during long sets was almost equally distributed between the first (37.1%) and second repetition (40.0%). Failure occurred before reaching the VLTs more frequently using PV (4, 8, and 33 occasions for 15%, 30%, and 45% VLTs, respectively) than MV (only 1 occasion for the 45% VLT). The participants rarely produced a velocity output above a VLT once this threshold was exceeded for the first time (≈10% and 30% of occasions during the short and long sets, respectively). Conclusions: The reference repetition and velocity variable are important factors to consider when implementing VLTs during resistance training. The fastest repetition (instead of the first repetition) and MV (instead of PV) are recommended.

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Marko Milic, Danica Janicijevic, Aleksandar Nedeljkovic, Ivan Cuk, Milos Mudric, and Amador García-Ramos

This study aimed to determine the instruction that maximizes fencing attack performance and to explore the sensitivity of a novel efficiency index (EI) that considers reaction time, attack velocity, and absolute error to discriminate between beginners and experienced fencers. Instructions that directed attentional focus internally (react as fast as possible and perform the attack movement as fast as possible) or externally (be as accurate as possible) were provided prior to stimulus presentation. The EI did not differ between the instructions in any group (p > .05), the instructions “react as fast as possible” and “be as accurate as possible” promoted in beginners the highest and the lowest EI, and the EI was higher for fencers. Our findings suggest that the EI could be recommended as a general index of fencing attack efficiency.

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Lazar Tomic, Danica Janicijevic, Aleksandar Nedeljkovic, Bojan Leontijevic, and Amador García-Ramos

Reliability and sensitivity of reaction time (RT) during quasi-realistic soccer situations was explored in 10 professional soccer players (skilled; age = 20.9 ± 3.6 years) and 10 males without soccer experience (nonskilled; age = 23.4 ± 0.5 years). The participants were instructed to react as fast as possible to a stimulus presented via the video-based method while standing on force platforms. RT was computed as the difference between the instant when the rate of force development of any leg reaches 5% of its maximal value and the instant of stimulus presentation. The results revealed acceptable to high reliability of RT (intraclass correlation coefficient median = .90; coefficient of variation ≤ 5.83%), and shorter RT for skilled compared with nonskilled participants in three out of eight comparisons (effect size range = 1.00–1.41). The video-based methods can be confidently used to assess the RT in soccer players.

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Milos R. Petrovic, Amador García-Ramos, Danica N. Janicijevic, Alejandro Pérez-Castilla, Olivera M. Knezevic, and Dragan M. Mirkov

Purpose: To test whether the force–velocity (F–V) relationship obtained during a specific single-stroke kayak test (SSKT) and during nonspecific traditional resistance-training exercises (bench press and prone bench pull) could discriminate between 200-m specialists and longer-distance (500- and 1000-m) specialists in canoe sprint. Methods: A total of 21 experienced male kayakers (seven 200-m specialists and 14 longer-distance specialists) participated in this study. After a familiarization session, kayakers came to the laboratory on 2 occasions separated by 48 to 96 hours. In a randomized order, kayakers performed the SSKT in one session and the bench press and bench pull tests in another session. Force and velocity outputs were recorded against 5 loads in each exercise to determine the F–V relationship and related parameters (maximum force, maximum velocity, F–V slope, and maximum power). Results: The individual F–V relationships were highly linear for the SSKT (r = .990 [.908, .998]), bench press (r = .993 [.974, .999]), and prone bench pull (r = .998 [.992, 1.000]). The F–V relationship parameters (maximum force, maximum velocity, and maximum power) were significantly higher for 200-m specialists compared with longer-distance specialists (all Ps ≤ .047) with large effect sizes (≥0.94) revealing important practical differences. However, no significant differences were observed between 200-m specialists and longer-distance specialists in the F–V slope (P ≥ .477). Conclusions: The F–V relationship assessed during both specific (SSKT) and nonspecific upper-body tasks (bench press and bench pull) may distinguish between kayakers specialized in different distances.

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Jesualdo Cuevas-Aburto, Ivan Jukic, Jorge Miguel González-Hernández, Danica Janicijevic, Paola Barboza-González, Luis Javier Chirosa-Ríos, and Amador García-Ramos

Purpose: To compare the effects of 2 upper-body strength-training programs differing in set configuration on bench press 1-repetition maximum (BP1RM), bench press throw peak velocity against 30 kg (BPT30), and handball throwing velocity. Methods: Thirty-five men were randomly assigned to a traditional group (TRG; n = 12), rest redistribution group (RRG; n = 13), or control group (n = 10). The training program was conducted with the bench press exercise and lasted 6 weeks (2 sessions per week): TRG—6 sets × 5 repetitions with 3 minutes of interset rest; RRG—1 set × 30 repetitions with 31 seconds of interrepetition rest. The total rest period (15 min) and load intensity (75% 1RM) were the same for both experimental groups. Subjects performed all repetitions at maximal intended velocity, and the load was adjusted on a daily basis from velocity recordings. Results: A significant time × group interaction was observed for both BP1RM and BPT30 (P < .01) due to the higher values observed at posttest compared with pretest for TRG (effect size [ES] = 0.77) and RRG (ES = 0.56–0.59) but not for the control group (ES ≤ 0.08). The changes in BP1RM and BPT30 did not differ between TRG and RRG (ES = 0.04 and 0.05, respectively). No significant differences in handball throwing velocity were observed between the pretest and posttest (ES = 0.16, 0.22, and 0.02 for TRG, RRG, and control group, respectively). Conclusions: Resistance-training programs based on not-to-failure traditional and rest redistribution set configurations induce similar changes in BP1RM, BPT30, and handball throwing velocity.