A Novel Approach for Athlete Profiling: The Unilateral Dynamic Strength Index

Effectiveness of an Individualized Training Based on Dynamic Strength Index on Sprinting, Jumping and Change of Direction Performance in Basketball Players: A Randomized Controlled Trial

The dynamic strength index (DSI) is calculated as the ratio between countermovement jump (CMJ) peak force and isometric mid-thigh pull (IMTP) peak force and is said to inform whether ballistic or strength training is warranted for a given athlete. This study assessed the impact of an individualized in-season resistance training program, guided by DSI on basketball players' physical performance. Forty-three elite players (19.4 ± 2.9 years; 1.97 ± 0.08 cm; 89.1 ± 9.5 kg) were divided into an intervention group (IG) (27 players) and a control group (CG) (16 players). The IG was further split based on DSI into a ballistic group (DSI ≤ 0.90, 11 players) and a strength group (DSI > 0.90, 16 players). Over five weeks, participants underwent two weekly resistance sessions, with the IG following a DSI-based program and the CG a standard program. Performance was measured pre- and post-intervention through 20-m sprints, 505 change of direction test, CMJ, and IMTP. There were statistically significant improvements in the IG, notably in sprint times (η2 = 0.12-0.21, p < 0.05) and 505 test (η2 = 0.15-0.16, p < 0.05), predominantly in the strength group. The CG's performance was either unchanged or declined for different variables. Our results suggest that DSI-guided training effectively enhances basketball players' physical performance within a competitive season.

INFLUENCES OF STRENGTH TRAINING ON ATHLETES’ SKILLS IN TABLE TENNIS

ABSTRACT Introduction The progressive advance of table tennis athletes’ competitive level demands restructuring the traditional strength training program to readjust itself to the current athletic abilities. Objective Explore a strategy based on strength training to improve table tennis athletes’ physical capacity and hitting ability. Methods Thirty table tennis students from a physical education college were selected as research volunteers. A strength training protocol was added to the traditional protocol in the experimental group. The duration of the exercises in the experimental group and the control group was the same, with a frequency of 3 times a week, totaling 9 weeks. Results The optimization scheme of the strength training combination proposed in this paper revealed an improved effect on table tennis players’ performance of hitting skills and fitness. Its range of improvement was greater than the traditional strength training scheme of the control group. Conclusion The optimization scheme combining strength training proposed in this paper can be adjusted to the training according to the athletes’ situation and benefit the athletes’ training efficiency. It can also prevent repetitive injuries caused by the standard training mode in the long run, increasing the athletes’ enthusiasm. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

INFLUENCE OF PROGRESSIVE UPPER LIMB STRENGTH TRAINING ON TABLE TENNIS ATHLETES

ABSTRACT Introduction Progressive strength training can help athletes improve their strength levels quickly and safely. By controlling the frequency and amplitude of vibrations, muscles can produce unconscious and voluntary contractions that help prevent diseases such as osteoporosis. Objective To explore the change in sports performance caused by progressive upper limb muscle strength training in table tennis players. Methods 12 table tennis players with a minimum experience of 5 years were randomly divided into experimental and control groups. The control performed traditional strength training methods while the experimental group used the progressive directed strength training method developed by the research team for nine weeks. Tests were performed on ISOMED 2000 equipment at the conditions of 60°/s and 450°/s. Results Circumference, muscle strength, and relative upper limb strength increased. In addition, a difference in the rate of the maximum elbow flexion moment of the athletes in the experimental group in the 60°/s test conditions was observed. At 450°/s, the maximum flexion and extension elbow moment showed a significant difference (P<0.05). Conclusion The progressive strength training method significantly affects the athletes’ maximum elbow flexion moment and maximum elbow extension moment than traditional strength training methods. Muscle strength progress was noted mainly in the elbow and wrist joints, with less intensity in the shoulders. Evidence Level II; Therapeutic Studies – Investigating the results.

Influence of Physical and Technical Aspects on Change of Direction Performance of Rugby Players: An Exploratory Study

We examined the relationships between change of direction (COD) speed and deficit, and a series of speed- and power-related measurements in national team rugby union players and analyzed the influence of movement patterns on COD ability. Eleven male athletes completed the following physical assessments on different days: day 1—anthropometric measurements, and lower-body kinematic parameters (assessed with eight inertial sensors) and completion time in COD tests (pro-agility, 45° cutting maneuver (CUT), and “L” (L-Drill)); day 2—bilateral and unilateral squat and countermovement jumps, 40 m linear sprint, and bar-power output in the jump squat and half-squat exercises. Pearson’s product–moment correlations were performed to determine the relationships between COD velocities, COD deficits, and the speed–power variables. Differences between players with higher and lower COD deficits were examined using magnitude-based inferences. Results showed that (1) greater sprint momentum was associated with higher COD deficits, particularly in drills with sharper angles and multiple directional changes (L-drill and pro-agility); (2) higher unilateral jump heights were associated with greater COD deficits in the pro-agility and L-drill but not in the CUT; (3) faster athletes were less efficient at changing direction and presented greater trunk and knee flexion angles during COD maneuvers, probably as a consequence of higher inertia.

Seasonal Variations in Game Activity Profiles and Players' Neuromuscular Performance in Collegiate Division I Basketball: Non-conference vs. Conference Tournament

Basketball has a high demand on a player's neuromuscular system due to a high volume of explosive high-intensity actions. This study aimed to examine the seasonal variations on game demands and players' neuromuscular performance during the Non-Conference (NON-CONF) and Conference (CONF) seasons in NCAA Division I Men's Basketball. Seven NCAA Division I Basketball players' (20 ± 1.2 years, 1.95 ± 0.1 m, and 94 ± 15 kg) match activity profiles were tracked in 17 home games (7 NON-CONF; 10 CONF); furthermore, players performed a repeat hop test on a force platform the day before competition to assess neuromuscular performance. A t-test for paired samples was used to analyze the differences between NON-CONF and CONF. Results indicated no significant differences in Total Distance, Peak Speed, Acceleration, and Deceleration loads when comparing NON-CONF and CONF match-play. Regarding neuromuscular performance, Jump Height (p = 0.03; ES = 0.43) was negatively affected during CONF. Moreover, a trend toward a decline in Peak Force (p = 0.06; ES = 0.38) was found in CONF. Conversely, no differences were obtained regarding Reactive Strength Index and Contact Time. In conclusion, match-play demands remained constant across the season whilst neuromuscular outputs were inhibited during the CONF season.