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Despite the abundance of research investigating the efficacy of caffeine supplementation on exercise performance, the physiological and biochemical responses to caffeine supplementation during intermittent activities are less evident. This study investigated the acute effects of caffeine supplementation on measures of exercise performance, ratings of perceived exertion, and biomarkers of oxidative stress induced by an acute bout of sprint interval training. In a randomized crossover design, 12 healthy males (age: 26 ± 4 years, height: 177.5 ± 6 cm, body mass: 80.7 ± 7.6 kg) ingested 6 mg/kg of caffeine or placebo 60 min prior to performing sprint interval training (12 × 6 s "all-out sprints" interspersed by 60 s of rest). Performance scores and ratings of perceived exertion were assessed after every sprint. Blood samples were collected before supplementation, prior to and following each sprint, and 5 and 60 min after the last sprint. Caffeine had no effect on any performance measures, ratings of perceived exertion, or biomarkers of oxidative stress (p >.05). In conclusion, caffeine supplementation does not improve performance or decrease oxidative stress after an acute bout of sprint interval training. [ABSTRACT FROM AUTHOR]

Purpose: To analyze the contribution of physical measures and external load in the match-based internal load of elite soccer players. Methods: Twenty-three elite soccer players (n = 23, age 26.69 ± 3.93 years, body mass 78.04 ± 5.03 kg, height 178.04 ± 5.19 cm, body fat 10.98 ± 1.25%) from a first division soccer team of the Brazilian Championship were evaluated first with anthropometric and physical measures (flexibility and muscle power of lower limbs), and after 24 hrs they were asked to perform an incremental treadmill test (VO[subscript 2]max and ventilatory thresholds). Subsequently, athletes were monitored for 6 weeks during nine official matches of a regional championship. On match days, the external load data (e.g., player load) were collected by triaxial accelerometers with GPS systems and post 30 min after the end of the match the internal load was assessed with the Session Rating of Perceived Exertion method (Session-RPE). Results: Our main findings showed significant contributions of the Player Load (r = 0.62, p < 0.001; 42.3%) and Anaerobic Threshold (r = -0.199, p = 0.05, 17%) for the predictive model of Session-RPE. Conclusions: Physical measures and external load have a significant influence on the internal load in elite soccer players. Our findings suggest that sport scientists can use the Session-RPE as a low-cost method for prescribing and monitoring training loads, by the influence of physical measures and external load on the match-based internal load, in order to optimize athletes' performance.

Purpose: This study investigated the effect of progressively adding sets for the lower limb every 2 wk versus performing a constant set volume in resistance-trained males. Methods: Thirty-one resistance-trained males (age = 24.4 ± 2.9 yr, height = 175.5 ± 6.5 cm, body mass = 80.1 ± 9.4 kg, body fat = 14.4% ± 3.1%, resistance training [RT] experience = 5.1 ± 2.2 yr; one-repetition maximum [1RM] barbell back squat: body mass ratio = 1.7 ± 0.1 a.u.) were randomly allocated into a constant group (CG, n = 10), a four-set progression group (4SG, n = 10) or a six-set progression group (6SG, n = 11). After a 2-wk washout period and another 2-wk familiarization period, participants performed a lower-limb training program twice a week for 12 wk. Maximum dynamic strength (1RM) in the barbell back squat, vastus lateralis cross-sectional area, and the sum of lateral thigh muscle thickness at 30%, 50%, and 70% of the femur length were assessed at baseline and after the 12-wk training program. Results: Regarding 1RM, multiple comparisons revealed that 6SG elicited higher muscle strength gains than 4SG (P = 0.002) and CG (P < 0.0001), and 4SG had greater improvements than CG (P = 0.023). Cross-sectional area and sum of lateral thigh muscle thickness showed no between-group differences (P = 0.067 and P = 0.076, respectively). However, an inspection of 95% confidence intervals suggests a potential dose–response relationship, with results appearing to plateau in the higher volume conditions. Conclusions: Our results suggest that progressively adding four or six sets per week every 2 wk elicited greater lower-limb strength in resistance-trained individuals over a 12-wk training period. Although our findings indicate a possible small benefit for higher volume conditions regarding hypertrophic adaptations in this population, the limited certainty of our findings warrants caution. [ABSTRACT FROM AUTHOR]

Purpose: We investigated the effect of drop-set (DS) and rest-pause (RP) systems compared to traditional (TRAD) resistance training on muscular adaptations and psychophysiological responses. Methods: Twenty-seven trained men (age: 23.4 ± 3.4 years; resistance training experience: 5.1 ± 1.7 years) were assigned to experimental groups (DS: n = 9, 3 × 10 repetitions at 75% with 6 additional repetitions at 55% 1RM; RP: n = 9, 3 × 16 repetitions at 75% 1RM; TRAD: n = 9, 4 × 12 repetitions at 70% 1RM) and performed lower-limb training sessions twice a week for 8 weeks. Maximum dynamic strength (1RM) and localized muscular endurance (LME) tests were performed in 45° leg press at baseline and post intervention. Session-RPE was assessed 15 min after the end of each training session. Results: A significant time vs. group interaction was observed for 1RM (p = .012) and LME (p < .0001). Post hoc comparisons revealed that RP elicited greater gains in muscular strength than DS (p = .044) but not TRAD (p = .116); and DS elicited greater LME than RP (p < .001) and TRAD (p = .001). No statistical differences were observed in Session-RPE and training strain between conditions; however, RP promoted higher training monotony (p = .036) than DS and TRAD. Conclusions: The DS and RP systems have a potential role in training programs aiming to promote muscle strength and localized muscular endurance adaptations, respectively. However, RP may promote higher training monotony than DS and TRAD, even though the other psychophysiological responses are similar. [ABSTRACT FROM AUTHOR]

Approach: In elite soccer, the physical, technical, and tactical variables must be analyzed in a complex and detailed way, aiming to improve the understanding of the teams' performances. However, these variables can be influenced by the playstyle of teams from the different continents. Purpose: This study aimed to compare the physical, technical, and tactical differences between the soccer teams from different continents (America, Europe, and Africa/Asia/Oceania) who participated in the 2018 FIFA World Cup. Forty-eight matches played during the group stage of the 2018 FIFA World Cup were analyzed. The data obtained were coded and calculated by a tracking system (GPS). The national teams were grouped according to the qualifiers for the 2018 FIFA World Cup and analyzed into three main groups (Europe: UEFA + Russia; America: CONMEBOL + CONCACAF; Africa/Asia/Oceania: CAF + AFC). Thirty-seven variables were analyzed and divided into tactical, physical, and technical parameters. Results: The results showed that athletes from the European teams were taller, covered a greater total distance faster (between 20 and 25 km.h-1), and spent more time in the opposing field (final third and penalty area) when compared to athletes from other continents. In contrast, athletes from the American continent were older (average age) and their attacks originated more from the left side of the field. Finally, Africa/Asia/Oceania athletes recovered a greater number of balls, had fewer corners, and their attacks originated more from the right side of the field. Conclusions: In summary, European teams had a more intense (physical parameters) and offensive playstyle (tactical) when compared to teams from other continents participating in the 2018 FIFA World Cup. [ABSTRACT FROM AUTHOR]

Zandona, BA, Ramos, RA, de Oliveira, CdS, McAnulty, SR, Ferreira, LHB, Smolarek, AC, Enes, AAN, Urbinati, KMdSS, Aragon, AA, Schoenfeld, BJ, and de Souza Junior, TP. Reduced Dose of Beta-Alanine Is Sufficient to Maintain Performance in Repeated Sprints. J Strength Cond Res 36(6): 1636–1642, 2022—Beta-alanine (BA) supplementation has been shown to be effective in improving physical performance by increasing carnosine concentration. However, it is still necessary to know the effect of a maintenance dose on performance. Thus, this study aimed to investigate the effects of a maintenance dose of BA supplementation on performance. Forty-four anaerobically trained men with 23.9 ± 3.8 years of age, 176.0 ± 0.05 cm height, 81.2 ± 7.5 kg body mass, and 15.5 ± 2.9% of body fat performed a cycle ergometer test consisting of 4 sprints of 30 s with 4 minutes of active recovery. The study comprised 3 phases: (a) presupplementation, (b) supplementation with 6.4 g·d−1 BA or placebo, and (c) postsupplementation with a maintenance dose of 1.2 g·d−1 of BA or interruption of supplementation. Data were analyzed using generalized estimated equations with a priori 0.05 level of significance. The placebo group and interruption group presented a lower power (7.28 ± 0.66 and 7.71 ± 0.42 W·kg−1 vs. 8.04 ± 0.84 and 9.25 ± 1.18 W·kg−1, respectively; p < 0.05) during the third sprint in postsupplementation, whereas the maintenance group maintained the required power (7.47 ± 1.03 vs. 8.74 ± 1.07 W·kg−1; p > 0.05). The placebo group also presented higher percentage of fatigue (44.5% ± 12.3 and 44.8% ± 7.7 vs. 37.6 ± 7.2%; p = 0.021) and higher subjective perception of exertion (8.92 ± 0.90 vs. 8.00 ± 1.60; p = 0.028). Therefore, the maintenance dose of 1.2 g·d−1 BA was effective in maintaining performance, whereas a reduction in performance was observed after supplementation interruption. [ABSTRACT FROM AUTHOR]

The aim of this study was to verify and compare the reaction time, swimming speed, partial- and final time of freestyle swimmers at the Beijing 2008 (B08), London 2012 (L12), and Rio 2016 Olympics (R16). 109 athletes (male (n = 57) and female (n = 52)), Olympics finalists were analyzed in the 100m, 200m, and 400m freestyle swimming events. ANOVA one-way multi-compare was used to verify the difference between reaction time (RT), partial time (PT), mean speed (MS), and final time (FT) in the analyzed Olympics. Statistical differences were found in the RT in the 100, 200, and 400m freestyle in females and 400m freestyle in males over the three Olympics, while for the mean speed the first 50 meters presented differences in the partial times, and for final time only the 100m female was different over the three Olympics. The race and partial time strategies had similar characteristics during the analyzed Olympics, while the reaction time of the athletes presented significant evolution over the Olympics. [ABSTRACT FROM AUTHOR]

Purpose: to compare Multiple-Set (MS) and Drop-Set (DS) systems on acute testosterone responses and at different moments for lymphocytes and monocytes in recreationally trained men. Methods: the study was composed of twelve male subjects(age: 22,5 ± 3,2 years; height: 176,3 ± 6,7 cm; body mass: 75,4 ± 6,9 kg) recreationally trained individuals. The participants performed the 1RM test in the Leg Press 45º and 48h post the first test, did the test again for the reproducibility of the loads. The participants were randomly for both protocols (MS: 3 x 10 reps - 75%1RM; DS: 3 x 10 reps at 80% - 40% - 20% of 1RM), which were separated by 72-hour interval between each one of them. The blood collect of testosterone levels were realized before the experimental protocols (baseline), immediately after (IP), 15-, 30- and 60-minutes after the protocols. Lymphocytes and monocytes were collected at baseline, IP, 24- and 48-hours after the experimental protocols. Results: MS showed an increase in the testosterone levels only at the IP and the DS showed higher values compared to MS. However, the effect size (ES) didn't showed significant differences between the different moments, both protocols presented small and trivial values. The monocytes (24 and 48 hours post-training) and lymphocytes (IP, 24 and 48 hours post-training) responses were higher in DS compared to MS, but these levels didn't exceed the reference values considered salutary. Conclusion: Both protocols are efficient in acute increases in testosterone levels. However, despite the higher values in testosterone levels on DS, when this values compared with MS, both protocols showed similar magnitude. In addition, the small fluctuations in lymphocytes and monocytes observed in both protocols didn't present clinical significance. [ABSTRACT FROM AUTHOR]

The purpose of this study was to verify the intensity of occurrence of the heart rate deflection point (HRDP) and the rating of perceived exertion threshold (DmaxRPE) in college students and to verify its correlation in the arm ergometer. Twelve male college students (age = 21.15 ± 3.13 yrs, weight = 80.79 ± 11.1 kg, height = 175.13 ± 3.84 cm, and body fat = 13.9 ± 3.86%) were subjected to a continuous test with an arm ergometer with initial workload of 12.5 W with increments of 5 W every 1 min until voluntary exhaustion. No meaningful differences in the intensity of occurrence of HRDP and DmaxRPE and the HR values related to HRDP and DmaxRPE (P>0.05) were found. Significant correlation was found between the intensity of occurrence of the HRDP and DmaxRPE (r = 0.887, P<0.05). The results indicate that there is a correlation between the HRDP and a RPE obtained through the Dmax method. [ABSTRACT FROM AUTHOR]

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Football is consider a global sports phenomenon and there is a pleasure attached to the act of cheering. Such a feeling requires the understanding of the extent that this act may restrict the individual's enlightenment capacity as well as excite the violence. The present study aims to analyze the effectiveness of measuring single twists in classics in the state. During the period of the research, a data survey was carried out, referring to the main classics of the football teams of the A1 Series of the Campeonato Paulista and the Series A of the Brazilian Football Championship in 2015, 2016 and 2017, with a focus on identifying the levels of violence before and after the promulgation of the measure, which requires the presence of only one twist, in this case, the twist of the team principal of the classic. The results show that before the promulgation of the measure, there were 13 cases of violence because of the classics of São Paulo, and after the promulgation of the measure, there was a decrease for only 3 reported cases until the end of searches. In a conclusive way, there was a decrease in cases of violence in the classics analyzed after the promulgation of this measure, however, a short time after the promulgation of the measure, which makes - in a certain way - precipitated any statement regarding the effectiveness of this measure in the main classics of the state of São Paulo. [ABSTRACT FROM AUTHOR]

This study investigated the effects of biset, drop-set and traditional resistance training (RT) techniques on metabolic responses in resistance-trained males. Fifteen trained males (age 29.7 ± 6.1 years; body mass 83.4 ± 7.6 kg; RT experience 11.4 ± 6.7 years; one-repetition maximum (1RM) barbell bench press: body mass ratio 1.4 ± 0.1 a.u.) were assigned to three experimental conditions, in a randomized crossover design. The experimental conditions were bi-set (3×10 repetitions at 70%1RM in barbell bench press followed by 10 repetitions at 60%1RM in incline bench press), drop-set (3×10 repetitions at 70%1RM followed by 10 repetitions at 50%1RM in barbell bench press) and traditional RT (3×20 at 60%1RM in barbell bench press). A portable gas analyzer was used to assess energy expenditure and maximal oxygen uptake during the experimental protocols. Blood lactate levels were assessed at baseline and 1, 3, and 5 minutes after the training session. There were no differences for total training volume ( p = 0.999). Post hoc comparisons revealed that bi-set elicited higher aerobic energy expenditure ( p = 0.003 vs. drop-set; p < 0.001 vs. traditional RT) and aerobic oxygen consumption ( p = 0.034 vs. drop-set; p < 0.001 vs. traditional RT) than other RT schemes. There were no differences regarding anaerobic EE between-conditions ( p > 0.05). There was a main effect of time and condition for blood lactate levels ( p < 0.001). Post hoc comparisons revealed that drop-set training elicited higher blood lactate levels than traditional RT ( p = 0.009). The results suggest that RT techniques may have a potential role in optimizing metabolic responses in resistance-trained males.

Obesity induces several disorders, such as android obesity, insulin resistance, and coronary/peripheral artery disease, and obese individuals commonly have low adherence to training programs. Exercise at self-selected intensity is a feasible strategy to avoid dropouts of training routines. We aimed to assess the effects of different training programs at self-selected intensity on body composition, ratings of perceived exertion (RPE), feelings of pleasure and displeasure (FPD) and fitness outcomes (maximum oxygen uptake (VO2max) and maximum dynamic strength (1RM)) in obese women. Forty obese women ( n = 40; Body Mass Index: 33.2 ± 1.1 kg.m -2 ) were randomly allocated to combined training (CT = 10), aerobic training (AT = 10), resistance training (RT = 10) and control group (CG = 10). The frequency that CT, AT and RT performed the training sessions was 3 times per week during 8 weeks. Body composition (DXA), VO2max and 1RM were assessed at baseline and after intervention. All participants were on a restricted dietary intake aiming to ingest 2.650 kcal per day. Post hoc comparisons revealed that CT promotes a larger decrease in body fat percentage ( p = 0.001), body fat mass ( p = 0.004) than other groups. CT and AT elicited higher V • O2max increases ( p = 0.014) than RT and CG, and 1RM values were higher in CT and RT ( p = 0.001) than AT and CG at post-intervention. All training groups presented low RPE and high FPD over the training sessions, but only the CT was effective to reduce body fat percentage and body fat mass in obese women. In addition, CT was effective to increase simultaneously maximum oxygen uptake and maximum dynamic strength in obese women.