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Short introduction- Basketball play is classically accompanied with a significant loss of body water with a potential negative impact on both physical and cognitive performance 1. Very few studies have examined the impact of dehydration on biomechanical adjustments required to score in basketball, though joints angles, the position of the centre of mass and ball release parameters (i.e. height, release speed and angle) are among the best predictive factors of success in basketball shooting 2. Dehydration might alter the biomechanical requirements of successful shots and especially three-point shots (3PS) which generate 16% of points scored during a match. However, only 35% of 3PS are successful in game. Within this framework we analysed the effects of a controlled dehydration protocol on the success and technique of 3PS in elite basketball players. Changes in shooting technique were analysed through changes in body kinematics (i.e. 3D angles of the ankle, knee, hip, shoulder, elbow and wrist, and the height of the centre of mass) and ball release parameters (i.e. height, velocity and angle of the ball at release) of 3PS in a dynamic playing condition.
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 
    
      
 
   
  
        
         
  
 
i.e.   
      
       
         
  
           
    
         
      
          
   
      
          
       
    
    
            
 
 
     
  
    
      
    
PROFF ID.indd 1 10/09/10 14:28
  
   
 
  
     
       
    
         
1.    
2.         
3. 
4.         
          
5.    
        
        
Cite this article as:
     
Conicts of interest.—     
     
  
et al.
   
PROFF ID.indd 1 10/09/10 14:28
... In these studies, hypohydration established prior to simulated play was associated with increased ratings of fatigue and impaired attention [115], but had no effect on ratings of perceived exertion [113,114]. Louis et al. [116] reported that 2% hypohydration decreased 3-point shooting performance in seven of nine elite basketball players and increased ratings of perceived exertion compared to when they were euhydrated. Similarly, perceived exertion was higher when adolescent athletes began a 30-min series of basketball drills 2.5% hypohydrated compared to when they were permitted water intake (1.0% hypohydration) prior to performance testing, but there were no significant differences in measures of basketball performance [117]. ...
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Basketball players face multiple challenges to in-season recovery. The purpose of this article is to review the literature on recovery modalities and nutritional strategies for basketball players and practical applications that can be incorporated throughout the season at various levels of competition. Sleep, protein, carbohydrate, and fluids should be the foundational components emphasized throughout the season for home and away games to promote recovery. Travel, whether by air or bus, poses nutritional and sleep challenges, therefore teams should be strategic about packing snacks and fluid options while on the road. Practitioners should also plan for meals at hotels and during air travel for their players. Basketball players should aim for a minimum of 8 h of sleep per night and be encouraged to get extra sleep during congested schedules since back-to back games, high workloads, and travel may negatively influence night-time sleep. Regular sleep monitoring, education, and feedback may aid in optimizing sleep in basketball players. In addition, incorporating consistent training times may be beneficial to reduce bed and wake time variability. Hydrotherapy, compression garments, and massage may also provide an effective recovery modality to incorporate post-competition. Future research, however, is warranted to understand the influence these modalities have on enhancing recovery in basketball players. Overall, a strategic well-rounded approach, encompassing both nutrition and recovery modality strategies, should be carefully considered and implemented with teams to support basketball players’ recovery for training and competition throughout the season.
... The instructions were to complete a precise motion in the direction of the punching bag with maximal possible strength, as classically performed during their habitual training sessions. Participants wore an MVN Biomech Link suit (Xsens Technologies BV, Enschede, The Netherlands) collecting live kinematic data during the entire movement (Louis et al., 2018;Figueiredo et al., 2020). This suit was composed of 17 miniature inertial measurement units (IMU) strapped onto the body. ...
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Punching in boxing requires a combination of force and velocity of the acting arm, originating from an optimal synchronization of the different body segments. However, it is not well understood what kinematic parameters of the punching execution influence boxing performance the most. This study aimed to investigate the differences in punching execution between 15 potential Olympic medalist boxers (Elite group) and 8 younger well trained boxers (Junior group). Each athlete was equipped with an instrumented suit composed of 17 inertial measurement units (IMU) and were asked to perform several series of 3 standardized punch types (cross, hook and uppercut) with maximal force. Linear velocity, stability and punch forces were computed from the different sensors. Our findings show that Elite boxers systematically produced more force and at a higher velocity for the three punch types compared to Juniors. Further analysis revealed differences in joint contributions between Elite and Juniors, Juniors presenting a higher contribution of the shoulder for the three punch types. Finally ground reaction force imbalance between the front and rear foot was revealed in the cross only, in all boxers (60.6 ± 24.9 vs 39.4 ± 24.9 % and 54.1 ± 7.1 vs 45.9 ± 7.1 %, p ≤ 0.05, for the front vs. rear foot in Elite and Juniors, respectively) but not different between groups. These results have important implications for practitioners involved in the talent identification process, longitudinal follow-up, and training of boxers.
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It is unknown how hypohydration influences fine motor performance training and motor learning. Here, 30 participants (aged 19–46 years) were randomly assigned to a hypohydration (HYPO) or control (CON) group (both n = 15). Moderate hypohydration (~ 2.4% loss in body mass) was produced in HYPO via active dehydration before a 46 min fluid restricted rest period was undertaken. The conclusion of rest coincided with when CON attended the facilities. Both groups undertook a discrete sequence production task consisting of 6 training blocks, and returned ~ 300 min later to complete a delayed retention and transfer test while euhydrated. Bilateral pre-frontal cortex (PFC) haemodynamics were assessed using functional near-infrared spectroscopy throughout training and delayed learning assessments. Response time improved across training ( P < 0.01) and was similar between the groups (both P = 0.22). Analysis of training PFC haemodynamics revealed a significant group by block interaction for oxygenated (O 2 Hb; P < 0.01), but not deoxygenated haemoglobin ( P = 0.77). In training block 1, bilateral O 2 Hb was higher in HYPO ( P = 0.02), while bilateral O 2 Hb increased in CON between blocks 2–3 and 5–6 (both P ≤ 0.03). During the delayed retention and transfer test, no group differences or interactions were found in response time, response error, or PFC haemodynamics (all P ≥ 0.27). Moderate hypohydration does increase PFC activation during motor skill learning, however, this appears to be transient and of little consequence to training or delayed retention or transfer performance.
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The ability to shoot an effective jump shot in the sport of basketball is critical to a player’s success. In an attempt to better understand the aspects related to expert performance, researchers have investigated successful free throws and jump shots of various basketball players and identified movement variables that contribute to their success. The purpose of this study was to complete a systematic review of the scientific literature on the basketball free throw and jump shot for the purpose of revealing the critical components of shooting that coaches, teachers, and players should focus on when teaching, learning, practising, and performing a jump shot. The results of this review are presented in three sections: (a) variables that affect ball trajectory, (b) phases of the jump shot, and (c) additional variables that influence shooting.
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The present study analyzed the effect of increased distance on basketball jump shot outcome and performance. Ten male expert basketball players were filmed and a number of kinematic variables analyzed during jump shot that were performed from three conditions to represent close, intermediate and far distances (2.8, 4.6, and 6.4m, respectively). Shot accuracy decreased from 59% (close) to 37% (far), in function of the task constraints (p < 0.05). Ball release height decreased (p < 0.05) from 2.46 m (close) to 2.38m (intermediate) and to 2.33m (long). Release angle also decreased (p < 0.05) when shot was performed from close (78.92°) in comparison to intermediate distances (65.60°). While, ball release velocity increased (p < 0.05) from 4.39 m/s (close) to 5.75 m·s(-1) (intermediate) to 6.89 m·s(-1) (far). These changes in ball release height, angle and velocity, related to movement performance adaptations were suggested as the main factors that influence jump shot accuracy when distance is augmented. Key pointsThe increased distance leads to greater spatial con-straint over shot movement that demands an adapta-tion of the movement for the regulation of the accu-racy and the impulse generation to release the ball.The reduction in balls release height and release angle, in addition to the increase in balls release ve-locity, were suggested as the main factors that de-creased shot accuracy with the distance increased.Players should look for release angles of shooting that provide an optimal balls release velocity to im-prove accuracy.
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This study examined the effect of high intensity, moderate duration (40 min) exercise and water restriction on anaerobic power, vertical jumping height, and basketball shooting performance. Ten healthy male basketball players participated in two simulated '2 on 2 full-court' basketball games. Water consumption was permitted in one game (Wa) but not in the other (NWa), in a balanced cross-over design. Subjects began each game euhydrated. All jump tests (squat jump, counter movement jump, and 30 second jump test) were performed prior to, at half-time, and immediately following each game (POST). Performance was measured by both field goal (FG%) and free throw (FT%) percentages recorded during each half. Players incurred a -1.9 +/- 0.4% body weight loss during NWa. No significant differences were observed between WA and NWa in anaerobic power, squat jump, or counter movement jump. However, a 19% difference in anaerobic power (p > 0.05) was observed between Wa (36.1 +/- 4.8 and NWa (30.4 +/- 6.6 at POST. No significant differences were observed between Wa and NWa in both FG% and FT% however, an 8.1% decrease (p > 0.05) in FG% was seen between the first and second half during NWa. Although the decreases in anaerobic power and FG% did not reach significance, the results suggest that the combination of high intensity, moderate duration exercise, and fluid restriction might be detrimental to performance.
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Three-dimensional cinematography (100 Hz) was used to establish the relationship between distance and the kinematics of shooting with respect to playing position in basketball. Fifteen subjects, divided into guards, forwards and centres (all n = 5), performed jump shots from each of three distances: 2.74, 4.57 and 6.40 m from the basket. Increases in mean release speed were found as shooting distance increased for all groups. This was due to increased angular velocities of both shoulder flexion and elbow extension and an increased speed of the centre of mass in the direction of the basket. Release angles for the two shorter distances (52-55 degrees) tended to provide the advantage of a steep angle of entry into the basket, whereas those at the longest distance (48-50 degrees) were closer to those requiring the minimum possible release speed. All groups exhibited an earlier timing of release as shooting distance increased, which gave rise to an earlier rotation of the shoulder axis. The more consistent changes in kinematic patterns with changes in shooting distance exhibited by guards as compared to centres would suggest that such adjustments are easier to make for those players who regularly shoot from long range.
The objective of this study was to investigate the coordination of a whole-body task (basketball free-throw) in which success in performance outcome can be achieved through a manifold of combinations of postural and movement trajectory configurations. Participants were healthy men (19–24 years) with a range of skill levels that were tested for the accuracy of 50 basketball free-throws with both their dominant and non-dominant hand. The trial-to-trial variance in release parameters as well as postural stability of the shooter and synchronization of postural movement and ball release were strong predictors of performance, with non-elite shooters having a higher mean and variability of center-of-mass (COM) speed at the time of ball release. The synchronization between the time of peak COM and the time of ball release increased as a function of skill level and hand dominance, with the better performers releasing the ball more closely to the time of COM peak height. These findings reveal how, in addition to successfully controlling the trial-to-trial variability along the solution manifold of release parameters, the relative importance of the coordination of postural control and ball release properties on shooting success changes as a function of skill level.
The purpose of this case study is to establish how a gradual increase in fatigue affects the position of the arms and shoulders during a long shot in a basketball game. For this purpose, Primoz Brezec, an elite National Basketball Association player, performed a total of 7 series of 20 shots from a distance of 7.24 m. The subject performed a special basketball motor task between individual series' of shots. The fatigue gradually increased with each motor task, and in the meantime, the subject's heart rate (HR) and blood lactate concentration (LA) were measured. The height of each jump during the shot at the basket was measured, and all shots were recorded using a system of 3 digital cameras operating at a frequency of 50 Hz. Thereafter, a kinematic analysis was applied to calculate the height of the shoulder and wrist of the release arm, as well as the elbow and upper arm angles, with regard to the vertical line. The study results reveal statistically significant differences (p < 0.05) between the series of throws in all measured variables. The heights of the shoulder axis and of the wrist both decrease with growing fatigue. This is particularly apparent in the last series, i.e., in the conditions of maximum fatigue (HR = 96% HRpeak; LA = 9.7 mmolxL). Both measured angles decrease drastically in the last series of shots. The results of the study clearly demonstrate changes in the shooting technique as a consequence of moderate and, in particular, heavy fatigue. The findings also suggest the need for basketball coaches and basketball conditioning coaches to include moderate- and high-intensity exercise in their shooting practice sessions.
Urine specific gravity (USG) has been used to estimate hydration status in athletes on the field, with increasing levels of hypohydration indicated by higher USG measurements (eg, greater than 1.020). Whether initial hydration status based on a urine measure is related to subsequent drinking response during exercise or athletic competition is unclear. To determine the relationship between pregame USG and the volume of fluid consumed by players in a professional basketball game. Cross-sectional study. Basketball players were monitored during Summer League competition. Players (n = 29) from 5 teams of the National Basketball Association agreed to participate. Pregame USG was measured for each player on 2 occasions. Athletes were given ad libitum access to fluid during each game and were unaware of the purpose of the study. Volume of fluid intake was measured for each player. To assess sweat loss, athletes were weighed in shorts before and after each game. Sweat loss ranged from 1.0 to 4.6 L, with a mean sweat loss of 2.2 +/- 0.8 L. Fluid intake ranged from 0.1 to 2.9 L, with a mean fluid intake of 1.0 +/- 0.6 L. Pregame USG was greater than 1.020 in 52% of the urine samples collected and was not correlated with fluid volume consumed during either of the games (r = 0.15, P = .48, and r = 0.15, P = .52, respectively). Approximately half of the players began the games in a hypohydrated state, as indicated by USG. Fluid intake during the game did not compensate for poor hydration status before competition. Furthermore, sweat losses in these players during games were substantial (greater than 2 L in approximately 20 minutes of playing time). Therefore, both pregame and during-game hydration strategies, such as beverage availability and player education, should be emphasized.
The phenomenon of involuntary dehydration, the delay in full restoration of a body water deficit by drinking, has been described extensively but relatively little is known about its physiological mechanism. It occurs primarily in humans when they are exposed to various stresses including exercise, environmental heat and cold, altitude, water immersion, dehydration, and perhaps microgravity, singly and in various combinations. The level of involuntary dehydration is approximately proportional to the degree of total stress imposed on the body. Involuntary dehydration appears to be controlled by more than one factor including social customs that influence what is consumed, the capacity and rate of fluid absorption from the gastrointestinal system, the level of cellular hydration involving the osmotic-vasopressin interaction with sensitive cells or structures in the central nervous system, and, to a lesser extent, hypovolemic-angiotensin II stimuli. Since humans drink when there is no apparent physiological stimulus, the psychological component should always be considered when investigating the total mechanisms for drinking.
There is a great demand for perceptual effort ratings in order to better understand man at work. Such ratings are important complements to behavioral and physiological measurements of physical performance and work capacity. This is true for both theoretical analysis and application in medicine, human factors, and sports. Perceptual estimates, obtained by psychophysical ratio-scaling methods, are valid when describing general perceptual variation, but category methods are more useful in several applied situations when differences between individuals are described. A presentation is made of ratio-scaling methods, category methods, especially the Borg Scale for ratings of perceived exertion, and a new method that combines the category method with ratio properties. Some of the advantages and disadvantages of the different methods are discussed in both theoretical-psychophysical and psychophysiological frames of reference.