No Effect of Caffeine Supplementation on Dribbling Speed in Elite Basketball Players

2019 ◽  
Vol 14 (7) ◽  
pp. 997-1000 ◽  
Author(s):  
Aaron T. Scanlan ◽  
Vincent J. Dalbo ◽  
Daniele Conte ◽  
Emilija Stojanović ◽  
Nenad Stojiljković ◽  
...  
Keyword(s):  
Body Mass ◽  
Effect Size ◽  
Science Research ◽  
Crossover Design ◽  
Basketball Players ◽  
Double Blind ◽  
Sport Science ◽  
Performance Time ◽  
Small Effect Size ◽  
Performance Times

Purpose: To examine the effect of caffeine supplementation on dribbling speed in elite female and male basketball players. Methods: A double-blind, counterbalanced, randomized, crossover design was used. Elite basketball players (N = 21; 10 female, 11 male; age 18.3 [3.3] y) completed placebo (3 mg·kg−1 of body mass of dextrose) and caffeine (3 mg·kg−1 of body mass) trials 1 wk apart during the in-season phase. During each trial, players completed 20-m linear sprints with and without dribbling a basketball. Performance times were recorded at 5-, 10-, and 20-m splits. Dribbling speed was measured using traditional (total performance time) and novel (dribble deficit) methods. Dribble deficit isolates the added time taken to complete a task when dribbling compared with a nondribbling version of the same task. Comparisons between placebo and caffeine conditions were conducted at group and individual levels. Results: Nonsignificant (P > .05), trivial to small (effect size = 0.04–0.42) differences in dribbling speed were observed between conditions. The majority (20 out of 21) of players were classified as nonresponders to caffeine, with 1 player identified as a negative responder using dribble-deficit measures. Conclusions: Results indicate that caffeine offers no ergogenic benefit to dribbling speed in elite basketball players. The negative response to caffeine in 1 player indicates that caffeine supplementation may be detrimental to dribbling speed in specific cases and emphasizes the need for individualized analyses in nutrition-based sport-science research.

scholarly journals The Effect of Dietary Nitrate Supplementation on Physiology and Performance in Trained Cyclists

2017 ◽  
Vol 12 (5) ◽  
pp. 684-689 ◽  
Author(s):  
Joseph A. McQuillan ◽  
Deborah K. Dulson ◽  
Paul B. Laursen ◽  
Andrew E. Kilding
Keyword(s):  
Time Trial ◽  
Crossover Design ◽  
Moderate Intensity ◽  
Beetroot Juice ◽  
Double Blind ◽  
Dietary Nitrate ◽  
Performance Time ◽  
Exercise Economy ◽  
Nitrate Supplementation ◽  
And Performance

Purpose:To determine the effect of dietary nitrate (NO3 –) supplementation on physiology and performance in well-trained cyclists after 6–8 d of NO3 – supplementation.Methods:Eight competitive male cyclists (mean ± SD age 26 ± 8 y, body mass 76.7 ± 6.9 kg, VO2peak 63 ± 4 mL · kg–1 · min–1) participated in a double-blind, placebo-controlled, crossover-design study in which participants ingested 70 mL of beetroot juice containing ~4 mmol NO3 – (NIT) or a NO3 –-depleted placebo (PLA), each for 8 d. Replicating pretreatment measures, participants undertook an incremental ramp assessment to determine VO2peak and first (VT1) and second (VT2) ventilatory thresholds on d 6 (NIT6 and PLA6), moderate-intensity cycling economy on d 7 (NIT7 and PLA7), and a 4-km time trial (TT) on d 8 (NIT8 and PLA8).Results:Relative to PLA, 6 d of NIT supplementation produced unclear effects for VO2peak (mean ± 95% confidence limit: 1.8% ± 5.5%) and VT1 (3.7% ± 12.3%) and trivial effects for both VT2 (–1.0% ± 3.0%) and exercise economy on d 7 (–1.0% ± 1.6%). However, effects for TT performance time (–0.7% ± 0.9%) and power (2.4% ± 2.5%) on d 8 were likely beneficial.Conclusions:Despite mostly unclear outcomes for standard physiological determinants of performance, 8 d of NO3 – supplementation resulted in likely beneficial improvements to 4-km TT performance in well-trained male endurance cyclists.

Caffeine Ingestion Improves Performance During Fitness Tests but Does Not Alter Activity During Simulated Games in Professional Basketball Players

2020 ◽  
pp. 1-8
Author(s):  
Javier Raya-González ◽  
Aaron T. Scanlan ◽  
María Soto-Célix ◽  
Alejandro Rodríguez-Fernández ◽  
Daniel Castillo
Keyword(s):  
Physical Performance ◽  
Body Mass ◽  
Effect Size ◽  
Basketball Players ◽  
Caffeine Ingestion ◽  
Repeated Sprint Ability ◽  
Repeated Sprint ◽  
Local Positioning System ◽  
Fitness Tests ◽  
Sprint Ability

Purpose: To examine the effects of acute caffeine supplementation on physical performance during fitness testing and activity during simulated games in basketball players. Methods: A double-blind, counterbalanced, randomized, crossover study design was followed. A total of 14 professional male basketball players ingested a placebo (sucrose) and caffeine (6 mg·kg−1 of body mass) in liquid form prior to completing 2 separate testing sessions. Each testing session involved completion of a standardized 15-minute warm-up followed by various fitness tests including 20-m sprints, countermovement jumps, Lane Agility Drill trials, and a repeated-sprint-ability test. Following a 20-minute recovery, players completed 3 × 7-minute 5-vs-5 simulated periods of full-court basketball games, each separated by 2 minutes of recovery. Local positioning system technology was used to measure player activity during games. Players completed a side-effects questionnaire 12 to 14 hours after testing. Results: Players experienced significant (P < .05), moderate–very large (effect size = −2.19 to 0.89) improvements in 20-m sprint, countermovement jump, Lane Agility Drill, and repeated-sprint-ability performance with caffeine supplementation. However, external workloads completed during simulated games demonstrated nonsignificant, trivial–small (effect size = −0.23 to 0.12) changes between conditions. In addition, players reported greater (P < .05) insomnia and urine output after caffeine ingestion. Conclusions: Acute caffeine supplementation could be effective to improve physical performance during tests stressing fitness elements important in basketball. However, acute caffeine supplementation appears to exert no meaningful effects on the activity completed during simulated basketball games and may promote sleep disturbances and exert a diuretic effect when taken at 6 mg·kg−1 of body mass in professional players.

scholarly journals Bilateral Symmetry of Jumping and Agility in Professional Basketball Players: Differentiating Performance Levels and Playing Positions

Symmetry ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1316
Author(s):  
Sime Versic ◽  
Miran Pehar ◽  
Toni Modric ◽  
Vladimir Pavlinovic ◽  
Miodrag Spasic ◽  
...  
Keyword(s):  
Effect Size ◽  
Vertical Jump ◽  
Bilateral Symmetry ◽  
Medium Effect ◽  
F Test ◽  
Basketball Players ◽  
Performance Levels ◽  
Small Effect Size ◽  
Medium Effect Size ◽  
And Performance

Although functional asymmetry is very common and normal in professional athletes, the better interlimb symmetry between dominant and nondominant sides (bilateral symmetry) could contribute to successful performance in basketball. The aim of this study was to evaluate the importance of bilateral symmetry of the one-leg jumping and agility performances in differentiating basketball players according to their (i) playing position (guards, forwards, and centers) and (ii) performance levels (first division vs. second division). The participants were 102 professional male basketball players, with all members of the teams competing in the two highest national divisions at the moment of testing (height: 194.92 ± 8.09 cm; body mass: 89.33 ± 10.91 kg; 21.58 ± 3.92 years of age). Performance levels (first division, N = 58 vs. second division, N = 44) and playing positions (guards, N = 48; forwards, N = 22; centers, N = 32) were observed as dependent variables. We measured one-leg jumping capacities (running vertical jump and lay-up vertical jump), basketball-specific preplanned agility (CODS), and basketball-specific reactive agility (RAG), all executed on dominant and nondominant sides. Accordingly, the bilateral symmetry of jumping and agility was calculated by calculating the ratio of the corresponding performances on the dominant and nondominant sides. Factorial analysis of variance (performance levels × positions) indicated that the bilateral symmetry of one-leg jumping differentiated players according to their playing position, with better bilateral symmetry among guards (F-test = 6.11 (medium effect size) and 5.81 (small effect size), p < 0.05 for lay-up and running-jump symmetry, respectively). Performance levels significantly differed in the bilateral symmetry of lay-up jump, with better symmetry for first-division players (F-test = 10.11 (medium effect size), p < 0.001), which was mostly influenced by significant differences among guards. Playing positions and performance levels did not differ in bilateral symmetry of the CODS and RAG. The study reveals the importance of bilateral symmetry of the sport-specific performance in differentiating playing positions and performance levels in basketball. Further studies in other multidirectional sports and other sport-specific performances are warranted.

scholarly journals Acute caffeine supplementation promotes small to moderate improvements in performance tests indicative of in-game success in professional female basketball players

2019 ◽  
Vol 44 (8) ◽  
pp. 849-856 ◽  
Author(s):  
Emilija Stojanović ◽  
Nenad Stojiljković ◽  
Aaron T. Scanlan ◽  
Vincent J. Dalbo ◽  
Ratko Stanković ◽  
...  
Keyword(s):  
Body Mass ◽  
Perceived Exertion ◽  
Ratings Of Perceived Exertion ◽  
Basketball Players ◽  
Double Blind ◽  
Arm Swing ◽  
Squat Jump ◽  
Professional Basketball ◽  
Perceived Performance ◽  
Testing Data

The aim of this study was to determine the effect of acute caffeine supplementation on anaerobic performance in professional female basketball players. A double-blind, placebo-controlled, experimental design was used in a randomized counterbalanced manner. In separate sessions, 10 professional basketball players ingested caffeine (3 mg/kg body mass) or a placebo (dextrose: 3 mg/kg body mass) 60 min before completing countermovement jumps (CMJ) with and without arm swing, a squat jump (SJ), the Lane Agility Drill, 20-m sprints (with 5-m and 10-m split times recorded) with and without dribbling a ball, and a suicide run. Participants provided ratings of perceived exertion (RPE) and ratings of perceived performance 30 min following testing. Data analyses included the use of effect size (ES) and significance. Caffeine supplementation produced small nonsignificant (p > 0.05) increases in CMJ without arm swing (ES = 0.30), CMJ with arm swing (ES = 0.29), SJ (ES = 0.33), and the lane agility drill (ES = –0.27). Caffeine supplementation produced small to moderate significant improvements in 10-m (ES = –0.63; p = 0.05) and 20-m (ES = –0.41; p = 0.04) sprint times without dribbling. Caffeine supplementation promoted a moderate significant reduction in RPE during the test battery (ES = –1.18; p = 0.04) and a small nonsignificant improvement in perceived performance (ES = 0.23; p = 0.53). Acute caffeine supplementation may produce small to moderate improvements in key performance attributes required for basketball while reducing RPE.

scholarly journals Feasibility of Combining Transcranial Direct Current Stimulation and Active Fully Embodied Virtual Reality for Visual Height Intolerance: A Double-Blind Randomized Controlled Study

2022 ◽  
Vol 11 (2) ◽  
pp. 345
Author(s):  
Samuel Bulteau ◽  
Andrew Laurin ◽  
Kalyane Bach-Ngohou ◽  
Morgane Péré ◽  
Marie-Anne Vibet ◽  
...  
Keyword(s):  
Virtual Reality ◽  
Direct Current ◽  
Effect Size ◽  
Transcranial Direct Current Stimulation ◽  
Cortisol Concentration ◽  
Controlled Study ◽  
Double Blind ◽  
Direct Current Stimulation ◽  
Sense Of Presence ◽  
Small Effect Size

Background: Transcranial Direct Current Stimulation (tDCS) and Virtual Reality Exposure Therapy (VRET) are individually increasingly used in psychiatric research. Objective/Hypothesis: Our study aimed to investigate the feasibility of combining tDCS and VRET with the features of wireless, 360° full immersion and embodiment and an active task to reduce height-induced anxiety. Methods: We carried out a pilot randomized, double-blind, controlled study associating VRET (two 20 min sessions with a 48 h interval, during which, participants had to cross a plank at rising heights in a building in construction) with online tDCS (targeting the ventromedial prefrontal cortex) with 28 participants. The primary outcomes were the sense of presence level and the tolerability. The secondary outcomes were the anxiety level (Subjective Unit of Discomfort) and the salivary cortisol concentration. Results: We confirmed the feasibility of the association between tDCS and fully embodied VRET associated with a good sense of presence without noticeable adverse effects. In both groups, a significant reduction in the fear of height was observed after two sessions, with only a small effect size of add-on tDCS (0.1) according to the SUD. The variations of cortisol concentration differed in the tDCS and sham groups. Conclusion: Our study confirmed the feasibility of the association between wireless online tDCS and active, fully embodied VRET. The optimal tDCS paradigm remains to be determined in this context to increase effect size and then adequately power future clinical studies assessing synergies between both techniques.

Electroconvulsive Therapy for Depression: A Review of the Quality of ECT versus Sham ECT Trials and Meta-Analyses

2019 ◽  
Vol 21 (2) ◽  
pp. 64-103 ◽  
Author(s):  
John Read ◽  
Irving Kirsch ◽  
Laura McGrath
Keyword(s):  
Electroconvulsive Therapy ◽  
Effect Size ◽  
Memory Loss ◽  
Severe Depression ◽  
Double Blind ◽  
End Of Treatment ◽  
Significant Difference ◽  
Small Effect Size ◽  
Meta Analyses

BackgroundElectroconvulsive therapy (ECT) is still being administered to approximately a million people annually. There have been no ECT versus simulated ECT (SECT) studies since 1985. The five meta-analyses of ECT versus SECT studies all claim that ECT is more effective than SECT for its primary target, severe depression. This review assesses the quality of those meta-analyses and of the 11 studies on which they are based.MethodsThe meta-analyses were evaluated primarily in terms of whether they considered the quality of the studies they included, but also in terms of whether they addressed efficacy beyond end of treatment. The methodological rigor of the 11 studies included by one or more of the meta-analyses was assessed using a 24-point Quality scale developed for this review.ResultsThe five meta-analyses include between 1 and 7 of the 11 studies. The meta-analyses pay little or no attention to the multiple limitations of the studies they include. The 11 studies have a mean Quality score of 12.3 out of 24. Eight scored 13 or less. Only four studies describe their processes of randomization and testing the blinding. None convincingly demonstrate that they are double-blind. Five selectively report their findings. Only four report any ratings by patients. None assess Quality of Life. The studies are small, involving an average of 37 people. Four of the 11 found ECT significantly superior to SECT at the end of treatment, five found no significant difference and two found mixed results (including one where the psychiatrists reported a difference but patients did not). Only two higher Quality studies report follow-up data, one produced a near-zero effect size (.065) in the direction of ECT, and the other a small effect size (.299) in favor of SECT.ConclusionsThe quality of most SECT–ECT studies is so poor that the meta-analyses were wrong to conclude anything about efficacy, either during or beyond the treatment period. There is no evidence that ECT is effective for its target demographic—older women, or its target diagnostic group—severely depressed people, or for suicidal people, people who have unsuccessfully tried other treatments first, involuntary patients, or children and adolescents. Given the high risk of permanent memory loss and the small mortality risk, this longstanding failure to determine whether or not ECT works means that its use should be immediately suspended until a series of well designed, randomized, placebo-controlled studies have investigated whether there really are any significant benefits against which the proven significant risks can be weighed.

Guidelines to Classify Female Subject Groups in Sport-Science Research

2016 ◽  
Vol 11 (2) ◽  
pp. 204-213 ◽  
Author(s):  
Lieselot Decroix ◽  
Kevin De Pauw ◽  
Carl Foster ◽  
Romain Meeusen
Keyword(s):  
Body Mass ◽  
Classification System ◽  
Female Subject ◽  
Maximal Oxygen Consumption ◽  
Science Research ◽  
Peak Power Output ◽  
Science Literature ◽  
Training Status ◽  
Sport Science ◽  
Review Current

Aim:To review current cycling-related sport-science literature to formulate guidelines to classify female subject groups and to compare this classification system for female subject groups with the classification system for male subject groups.Methods:A database of 82 papers that described female subject groups containing information on preexperimental maximal cycle-protocol designs, terminology, biometrical and physiological parameters, and cycling experience was analyzed. Subject groups were divided into performance levels (PLs), according to the nomenclature. Body mass, body-mass index, maximal oxygen consumption (VO2max), peak power output (PPO), and training status were compared between PLs and between female and male PLs.Results:Five female PLs were defined, representing untrained, active, trained, well-trained, and professional female subjects. VO2max and PPO significantly increased with PL, except for PL3 and PL4 (P < .01). For each PL, significant differences were observed in absolute and relative VO2max and PPO between male and female subject groups. Relative VO2max is the most cited parameter for female subject groups and is proposed as the principal parameter to classify the groups.Conclusion:This systematic review shows the large variety in the description of female subject groups in the existing literature. The authors propose a standardized preexperimental testing protocol and guidelines to classify female subject groups into 5 PLs based on relative VO2max, relative PPO, training status, absolute VO2max, and absolute PPO.

scholarly journals The Importance of Biological Maturation and Years of Practice in Kayaking Performance

2021 ◽  
Vol 18 (16) ◽  
pp. 8322
Author(s):  
Rui António Fernandes ◽  
Daniel López-Plaza ◽  
Lorena Correas-Gómez ◽  
Beatriz Branquinho Gomes ◽  
Fernando Alacid
Keyword(s):  
Body Mass ◽  
Adult Height ◽  
Performance Time ◽  
Sitting Height ◽  
Biological Maturation ◽  
Specific Practice ◽  
And Performance ◽  
Performance Times

Previous canoe sprint studies evaluated the best paddlers of their categories. This investigation aimed to identify the importance of biological maturation and athletes’ experience in kayaking performance and observe possible differences regarding anthropometry, years of practice, and performance. Eighty under 14 years of age (U14) and fifty under 16 years of age (U16) kayakers aged 13.40 ± 0.54 and 15.25 ± 0.61 years were evaluated. Kayakers were assessed for anthropometry (body mass (kg); stretch stature (cm); and sitting height (cm)), performance (time at 3000 m for U14 and 5000 m for U16 kayakers), and somatic maturation (predicted adult height (PAH) and maturity offset). In the U14 kayakers, years of practice, sitting height, and maturity offset showed significant differences (p < 0.05) between the Top10 and Middle, and Middle and Bottom10 performance times. Significantly higher (p < 0.05) sitting heights were identified between the Top10 and Middle U16 kayakers. Significant differences (p < 0.05) were observed for maturity offset and PAH% between the Top10 and Middle groups compared to the Bottom10 group. In conclusion, this research shows differences in the maturity status of young U14 and U16 kayakers, identifying that the more biologically mature individuals, with more years of specific practice, achieved better performances.

Caffeine supplementation for 4-day, followed by acute ingestion, did not impact triathlete output power after submaximal intensity exercise

2019 ◽  
Vol 18 (3) ◽  
pp. 118
Author(s):  
Anderson Pontes Morales ◽  
Felipe Sampaio-Jorge ◽  
Thiago Barth ◽  
Alessandra Alegre De Matos ◽  
Luiz Felipe Da Cruz Rangel ◽  
...  
Keyword(s):  
Blood Lactate ◽  
Output Power ◽  
Body Mass ◽  
Effect Size ◽  
Power Output ◽  
Anaerobic Power ◽  
Lactate Concentration ◽  
Wingate Test ◽  
Large Effect Size ◽  
Acute Ingestion

Introduction: The aim of this study was to test the hypothesis that caffeine supplementation (6 mg·kg-1 body mass) for 4-days, followed by acute intake, would impact five male triathletes output power after performed submaximal intensity exercise. Methods: This was a randomized, double-blind, placebo-controlled crossover study, placebo (4-day) - placebo (acute) PP, placebo (4-days) -caffeine (acute) PC, and caffeine (4-day) - caffeine (acute) CC. Participants abstained from dietary caffeine sources for 4 days and ingested capsules containing either placebo or caffeine (6 mg.kg-1 body mass day in one absorption). The acute trials the capsules containing placebo or caffeine (6 mg.kg-1 body mass day in one absorption) were ingested 60min before completing exercise in a treadmill for 40min (80% VO2max) and to perform the Wingate test. Results: Blood lactate was determined before, 60min after ingestion, and immediately after the exercise on the treadmill, the Wingate test, and after the recovery (10-min). CC and PC trials did not change the cardiopulmonary variables (P>0.05) and the anaerobic power variables (peak/mean power output and fatigue index) (P>0.05). The PC trial compared with PP promoted improvements in the curve power output in 2 sec by 31.19% (large effect-size d = 1.08; P<0.05) and 3 sec by 20% (large effect-size d = 1.19; P<0.05). A 10min recovery was not sufficient to reduce blood lactate concentration in the PC trial compared with PP (PC, 13.73±2.66 vs. PP, 10.26±1.60 mmol.L-1; P<0.05, respectively) (P<0.05). Conclusion: In conclusion, these results indicate that caffeine supplementation (6 mg·kg-1 body mass) for 4 days, followed by acute ingestion, did not impact the triathletes output power after performed submaximal intensity exercise. Nutritional interventions may help researchers and athletes to adapt strategies for manipulating caffeine use.Key-words: caffeine metabolism, Wingate test, blood lactate, performance.

scholarly journals Comparison of Official and Friendly Matches through Acceleration, Deceleration and Metabolic Power Measures: A Full-Season Study in Professional Soccer Players

2021 ◽  
Vol 18 (11) ◽  
pp. 5980
Author(s):  
Hadi Nobari ◽  
Sara Mahmoudzadeh Khalili ◽  
Rafael Oliveira ◽  
Alfonso Castillo-Rodríguez ◽  
Jorge Pérez-Gómez ◽  
...  
Keyword(s):  
Effect Size ◽  
Total Duration ◽  
Soccer Players ◽  
Metabolic Power ◽  
Professional Soccer ◽  
Premier League ◽  
Small Effect Size ◽  
Moderate Effect Size ◽  
High Effort

Soccer is a popular team sport and highly demanding activity that requires high effort and long-term training plans. The goals of this study were to compare the accelerations, decelerations and metabolic power between official and friendly full matches, between the first and second halves of the matches, and between both halves of official and friendly matches. Twelve professional soccer players (age, 28.6 ± 2.7 years; height, 182.1 ± 8.6 cm; body mass, 75.3 ± 8.2 kg; BMI, 22.6 ± 0.7 kg/m2) participated in this study. A total of 33 official and 10 friendly matches were analyzed from the Iranian Premier League. All matches were monitored using GPSPORTS systems Pty Ltd. The following variables were selected: total duration of the matches, metabolic power, accelerations Zone1 (<2 m·s−2) (AccZ1), accelerations Zone2 (2 to 4 m·s−2) (AccZ2), accelerations Zone3 (>4 m·s−2) (AccZ3), decelerations Zone1 (<−2 m·s−2) (DecZ1), decelerations Zone2 (−2 to −4 m·s−2) (DecZ2) and decelerations Zone3 (>−4 m·s−2) (DecZ3). The major finding was shown in metabolic power, where higher values occurred in friendly matches (p < 0.05 with small effect size). Furthermore, total duration, AccZ3, DecZ1, DecZ2, and DecZ3 were revealed to be higher in official matches, while AccZ1 and AccZ2 were higher in friendly matches. The second half of the official matches revealed higher values for total duration compared to friendly matches (p < 0.05, moderate effect size). In conclusion, this study observed higher values of metabolic power in friendly matches compared to official matches. AccZ3, DecZ1, DecZ2, and DecZ3 were higher in official matches, while AccZ1 and AccZ2 were higher in friendly matches.

Sign in / Sign up

Export Citation Format

Share Document