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PURPOSE: To assess the variations in power performance and perceptual training responses and compare the physical performance of national boxing athletes qualified or not qualified for the Tokyo Olympic Games over a 7-month training period. METHODS: Twelve amateur boxers from the Brazilian national team were tested 6 times across 7 months. In the first assessment, boxers performed squat and countermovement jumps and bench press, prone bench pull, half squat, and jump squat power tests. In the following testing sessions, only countermovement jump and bench press power were assessed. In addition, the rating of perceived exertion and total quality recovery status were assessed in 106 training sessions across the study. Independent t test and repeated-measures analysis of variance were used for data analysis purposes. RESULTS: No significant differences (P > .05) were observed between Olympic and non-Olympic groups for any test variables (effect size [95% CI] ranging from 0.01 [-1.13 to 1.13] to 0.69 [-0.53 to 1.79]). No significant changes (P > .05) were detected throughout the study for countermovement jump height and bench press power in either group (effect size [95% CI] ranging from 0.01 [-1.13 to 1.13] to 1.03 [-0.25 to 2.14]). Overall, both groups exhibited similar variations in both rating of perceived exertion and total quality recovery over the 7-month period. CONCLUSIONS: Within the same national team, power-related performance was similar between Olympic and non-Olympic boxers. The maintenance of power abilities and optimization of technical and tactical skills seem to be key issues to consider during the final stages of preparation for international boxing competitions.

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The number of offensive actions and glycolytic energy in combat sports both increase with caffeine (CAF) ingestion. In addition, the effects of CAF on technical-tactical and time-motion analysis and physiological parameters in boxing are unknown. This study aimed to investigate the effects of CAF ingestion on physiological parameters and the notational analysis of boxing matches. Ten male boxers were recruited; the participants ingested 6 mg kg-1 BM of CAF or placebo (PLA) 30 min prior to the match in a crossover design. Heart rate (HR) and rate of perceived exertion (RPE) were collected before and after each of three 2 min rounds, interspersed by 1-min recovery; the matches were recorded for notational analysis. A two-way ANOVA for repeated measures was used for the physiological variables, and a three-way ANOVA with repeated measures was used for technical-tactical and time-motion variables. Statistical differences were found for HR and RPE between rounds (F(6, 54) = 131.3, p = .001; [Formula: see text] = 0.93 and F(2, 18) = 40.6, p = .001; [Formula: see text] = 0.81, respectively) but not between conditions (F(1, 9) = 0.46; p = .51; [Formula: see text] = 0.05 and F(1, 9) = 0.02, p = .89; [Formula: see text] = 0.002, respectively). The CAF condition induced a greater duration of interaction blocks (CAF = 6.5 ± 1.8 s; PLA = 4.4 ± 0.9 s; p = .01). Effort:pause ratio was 4.4 s:8.7 s (approx. 1:2) for PLA and 6.5 s:9.4 s (1:1.44) for CAF, which were significantly different (p < .05). In conclusion, 6 mg kg-1 BM of CAF prior to simulated boxing matches induces a greater duration of high-intensity actions, with no effects on internal load markers.

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OBJECTIVE: To evaluate whether virtual reality games (VRGs) in stroke survivors produce significant and reproducible heart rate and oxygen consumption (V˙o2) responses during their execution, corresponding to an intensity between the anaerobic threshold (AT) and the respiratory compensation point (RCP). DESIGN: Single-subject, repeated-measure design. SETTING: Stroke survivors registered from a rehabilitation program. PARTICIPANTS: Chronic hemiparetic stroke survivors (N=12; 10 men; mean age ± SD, 58±12y) rated at 3 or 4 in the Functional Ambulation Categories. INTERVENTIONS: Participants underwent, in a random order, 2 identical sessions of VRGs (console Xbox 360 + Kinect) and 1 control session (38min watching a movie). The VRG sessions were composed of 4 sets of VRGs (3min of tennis, 1min for changing the game, and 4min of boxing) interspaced with 2 minutes of rest. MAIN OUTCOME MEASURES: Heart rate and V˙o2 were measured during the experimental sessions and compared with heart rate and V˙o2 obtained at AT and RCP assessed during a maximal cardiopulmonary exercise test. RESULTS: Heart rate and V˙o2 during VRGs had good reproducibility (intraclass correlation coefficients, ≥.91 and ≥.85, respectively; coefficients of variation, ≤6.7% and ≤13.7%, respectively). Heart rate during VRGs was similar to AT and significantly lower than RCP (P≤.05), while V˙o2 was significantly lower than AT and RCP (P<.05). CONCLUSIONS: An acute session of VRGs composed of tennis and boxing games using the console XBox 360 + Kinect promotes reproducible responses of heart rate and V˙o2 that corresponded, respectively, to AT and below AT, characterizing a low-intensity aerobic stimulus.

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This study investigated the relationship between punching impact and selected strength and power variables in 15 amateur boxers from the Brazilian National Team (9 men and 6 women). Punching impact was assessed in the following conditions: 3 jabs starting from the standardized position, 3 crosses starting from the standardized position, 3 jabs starting from a self-selected position, and 3 crosses starting from a self-selected position. For punching tests, a force platform (1.02 × 0.76 m) covered by a body shield was mounted on the wall at a height of 1 m, perpendicular to the floor. The selected strength and power variables were vertical jump height (in squat jump and countermovement jump), mean propulsive power in the jump squat, bench press (BP), and bench throw, maximum isometric force in squat and BP, and rate of force development in the squat and BP. Sex and position main effects were observed, with higher impact for males compared with females (p ≤ 0.05) and the self-selected distance resulting in higher impact in the jab technique compared with the fixed distance (p ≤ 0.05). Finally, the correlations between strength/power variables and punching impact indices ranged between 0.67 and 0.85. Because of the strong associations between punching impact and strength/power variables (e.g., lower limb muscle power), this study provides important information for coaches to specifically design better training strategies to improve punching impact.

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Objetivo: Verificar a influência de duas diferentes intensidades e volumes de treinamento resistido na pressão intraocular. Método: Dezenove boxeadores (13 homens e 6 mulheres; idade média de 22 ± 3 anos) foram randomicamente submetidos a duas diferentes sessões de exercícios resistidos: resistência muscular com 3 séries de 15 repetições máximas e hipertrofia muscular com 4 séries de 8RM. A pressão intraocular foi obtida com Tonometro de Perkins antes, durante e após as sessões de exercício resistido. Os dados foram expressos em média e desvio padrão. Foi realizada análise de variância (ANOVA) com medidas repetidas e pós teste de Tukey. Resultados: Foi observada redução da pressão intraocular durante as sessões de treinamento resistido. Contudo, a sessão de exercício para resistência muscular promoveu uma redução significativa da pressão intraocular comparada a de hipertrofia muscular. Ao final da sessão de resistência muscular a pressão intraocular retornou aos valores prévios ao exercício, por outro lado na sessão de hipertrofia muscular a pressão intraocular após o término dos exercícios apresentou-se acima dos valores iniciais. Conclusão: O treinamento resistido pode influenciar os valores da pressão intraocular, especificamente 3 séries de 15 repetições com 60% de 1RM promoveu respostas hipotensivas mais expressivas na pressão intraocular do que 3 séries de 8 repetições com 80% de 1RM. Esses achados podem contribuir para prescrição de exercício resistido para pessoas com fatores de risco para o glaucoma. .

Abstract Purpose: To verify the influence of two different intensities and volumes of resistance training on intraocular pressur. Method: Nineteen athletes boxers (13 male and 6 female; mean age of 22 ± 3 years) were randomly assigned to two different resistance exercise sessions: muscular endurance with 3 sets of 15 repetition maximum and muscular hypertrophy with 4 sets of 8 RM. The intraocular pressure was measured with a Perkins tonometer before, during and after the resistance exercise sessions. Data were expressed as mean and standard deviation. A repeated-measures analysis of variance (ANOVA) was used and the Tukey post hoc test for multiple comparisons were applied. Results: A reduction in intraocular pressure during the resistance exercise session was observed. However, the muscular endurance exercise produced a significant reduction in intraocular pressure when compared with muscular hypertrophy. At the end of session, intraocular pressure returned to pre-exercise levels in muscular endurance session and above to pre-exercise levels in hypertrophy session. Conclusion: Resistance exercises influence intraocular pressure values, thus 3 sets of 15 repetitions with 60%1RM promote better intraocular pressure responses than 3 sets of 8 repetitions with 80% 1RM. This finding of the present research can contribute in prescription of resistance exercise to people with glaucoma risk factors. .

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