Acta Kinesiologica

Relationship between bone mineral density and body compositions, strength, type of sport competition, vitamin D and birth-related factors in elite Polish track and field athletes: a cross-sectional study

Jakub Baldyka, Anna Kopiczko — Thu, 31 Oct 2024 00:00:00 +0100

Purpose: The purpose of this investigation was to characterize the forearm bone mineral density (BMD) in Elite Competitive
Track and Field Athletes. Somatic, body composition, hand grip strength birth variables, and blood vitamin D levels were
also analyzed.
Methods: In this cross-sectional study, the participants were 30 elite Polish athletes. Somatic measurements, body
composition by kinanthropometry, and bioelectrical impedance were taken. Forearm bone parameters were measured by
densitometry in two points distal (dis) and proximal (prox). Measurement of hand grip strength (HGS) on a dynamometer
was performed. Birth-related factors such as birth weight and length of breastfeeding were collected by direct interview.
Vitamin D concentration was assessed by blood test.
Results: Low BMD was not observed in the distal part of the forearm. Significantly more frequent low BMD prox were found
in endurance athletes (EA) group compared to throwing athletes group (TA) (χ2=10.8; P = .001; Φ= .6). Inadequate vitamin
D levels were significantly higher in the EA group compared to TA (χ2=10.8; P = .001; Φ= .6). The main parameters affecting
BMD dis and BMC prox of men athletes were HGS (kg) and type of sports competition (Rˆ2 adj= .93; .89). BMC dis was
affected by the type of sports competition (Rˆ2 adj= .83). There was also a significant relationship between the T-score prox
and the HGS (Rˆ2 adj= .98). In the case of women, the main parameters affecting BMD prox were menarche age and body
composition (Rˆ2 adj= .93). The BMC prox was affected by the age of the menarche (Rˆ2 adj= .73).
Conclusions: In conclusion, the present study found that the highest BMD of the forearm bones was characterized by men
and women athletes training in athletic throws relative to running sports. Screening assessment of bone mineral status
should be included in sports diagnostics.

Effects of Different Endurance Training Models on Players’ Fitness Levels during the National Break in the Football Season

Gülbin Rudarlı, Murat Tutar, Bülent KAYITKEN — Thu, 31 Oct 2024 00:00:00 +0100

Purpose: This pilot study aims to determine the effects of different endurance exercises, during the 14-day national break
during the football season.
Methods: Four groups were formed randomly from 44 male football players (age 17-19 years old, stature 179.0±6.16 cm,
body mass 70.4±5.53 kg, and body fat ratio 10.6±2.18 %) who regularly train and compete in the youth category of a football
team: Small-Sided Games (SSG, n=10), Large-Sided Games (LSG, n=18), Running Without the Ball (RWB, n=8), and Control
group (CG, n=8). VO2max (30-15 IFT and Bruce Protocol), balance (Y test), 10-20-30 m sprint, and T-test before and after the
14-day national break during the football season were measured. Heart rate and rate of perceived exertion (RPE) followed
during the training program.
Results: Significant differences were found in SSG (P= .001) and LSG (P= .005) in 30-15 IFT test (P< .05). In the Y-balance
test, a statistically significant difference was found in SSG (P= .001) and LSG (P= .001) only.
Conclusions: As a result, coaches are recommended to apply one of the RWB, SSG, or LSG training in addition to their routine
football periods.

Postural Sway Characteristics in Static Balance Control of Youth Female Soccer Players

eryk przysucha, Carlos Zerpa, erica vidotto, Liam Puskas, Carl Goodwin — Thu, 31 Oct 2024 00:00:00 +0100

Purpose: Balance control, particularly in uni-lateral domain, is essential in soccer. Majority of the existing studies examined
dynamic balance via clinical tools, and primarily involved male players. Thus, the purpose here was to examine the nature of
Center of Pressure (COP) postural sway in youth female players across bipedal and unipedal conditions
Methods: Sixteen pre-adolescent female competitive players (age 12.4±21.40 years) were asked to stand on a force plate
in bi-pedal stance with the dominant and non-dominant legs respectively. Three, 10 second trials were carried out for each
condition.
Results: As expected, across the four COP measures bi-pedal stance resulted in least sway (P= .05). However, the subsequent
analysis showed different center of pressure (COP) profiles in the dominant versus non-dominant condition across COP
velocity (P= .003), path length (P= .001) and anterior-posterior (AP) sway (P= .003), with sway area revealing no statistical
differences (P= .821). In addition, the analysis of stabilograms confirmed that in the non-dominant condition the pronounced
COP oscillations were of lower amplitude and frequency as compared to the dominant leg.
Conclusions: Overall, postural asymmetry was found as the sway characteristics on both legs differed, with dominant side
exhibiting more sway and faster COP oscillations. In line with the inverted pendulum model, this may be due to less than
optimal ability to modulate muscle torques generated at the ankle. It is hypothesized that the postural asymmetry between
the dominant and non-dominant legs may result from muscular asymmetries that have been often reported in youth soccer
players, as a result of their pronounced foot dominance.

Asymmetries in Postural Stability and Balance Parameters during Specific Elements in Sub-Elite Rhythmic Gymnasts

Iva Macan, Marin Marinovic, Ana Kezic — Thu, 31 Oct 2024 00:00:00 +0100

Purpose: This study aims to investigate the level of lower-limb functional asymmetries in sub-elite rhythmic gymnasts while
performing sport-specific elements, including passe and side passe balance stance.
Methods: The analysis focuses on postural stability and balance parameters, measured using Gyko, a 3-axis accelerometer,
gyroscope, and magnetometer device. The task was to execute a passe balance and maintain the position for 30 seconds,
which was the duration of the test, and then perform the same task with the other leg. The test was repeated for both legs in
a side passe balance stance. Sixteen active female sub-elite rhythmic gymnasts participated in the study.
Results: The results reveal significant differences in the mean travel velocity in all anatomical planes during the passe
elements, indicating asymmetry in postural stability in favor of the non-dominant leg (P≤ .01). Similarly, in the side passe
balance test, significant differences were observed in the mediolateral (in favor of the dominant leg) and anteroposterior (in
favor of the non-dominant leg) total distances, indicating asymmetry in postural stability (P= .03). However, no significant
differences were found in other postural stability parameters, the ellipse (EA) and the total length of the trajectory (Len(D)).
Conclusions: Evident asymmetries in movement speed during the passe element and imbalances in weight distribution
during the side passe balance test do not appear to compromise overall postural stability considering that asymmetry was
not proven in several variables, such as the ellipse or the total length of the trajectory. These findings shed light on the
potential impact of asymmetries on performance and injury risk in rhythmic gymnastics, emphasizing the importance of
considering sport-specific balance tests.

Acute effects of a dynamic stretching and core stability exercise protocol on physical performance in U-16 volleyball players

Thu, 31 Oct 2024 00:00:00 +0100

Purpose: Stretching and core exercises are is often used in different sports to develop higher sport performance and
reduce injury risks. In acute, dynamic stretching (DS) seems to produce more benefits than static for improving physical
performance. Moreover, sports tasks characterized by explosive and multi joints movement, such as wall jumping or dunking
and serving in volleyball, also require core stabilization. Therefore, the aim of present study was to evaluate a potential postactivation
potentiation enhancement (PAPE) effect induced by a functional exercise protocol including dynamic stretching
and stimulation of core stability (StretCor) on physical performance in a group of U-16 volleyball players.
Methods: Eighteen young volleyball players (9 boys and 9 girls; age: 15.33± .68 y; BMI: 22.12±2.25 kg.m-2) participating in the
regional championship were recruited by Italian Volleyball Federation (FIPAV) – Campania Committee. The StretCor protocol
consisted in eight exercises, performed with ball, combining both DS and Core Stability (CS) exercises that stimulates the
main muscles group. Before and after exercise protocol, Countermovement Jump (CMJ), modified Stars Excursion Balance
Test (mSEBT) and agility T-test performances were assessed in all participants.
Results: After StretCor protocol, there were improvements (P< .05) in agility T-test (10.48±1.01 vs 10.70±1.09 s), jump
height (31.81±5.36 vs 29.75±5.73 cm) and relative peak power (51.53±9.77 vs 46.04±6.21 W/kg). Moreover, in mSEBT,
left normalized Anterior (left ANT) (71.29±7.59 vs 66.84±7.19 %), Posteromedial direction (left PM) (105.63±8.80 vs
98.28±12.82 %), Posterolateral (left PL) directions (106.15±9.95 vs 98.47±13.06 %) and in right normalized Posterolateral
direction (right PL) (103.90±10.65 vs 98.14±12.95 %) were improved after StretCor protocol; in addition, improvement
were also observed in left (94.36±6.61 vs 87.87±9.88 %) and right (92.85±7.03 vs 88.47±10.22 %) composite (COMP) score.
Conclusions: The present study suggests that an acute session of StretCor protocol, improved lower limb muscle power,
dynamic balance and agility in U-16 volleyball players. We suggest including these types of exercises as a CA to produce a
PAPE effect in the warm-up phase of volleyball training for improve the physical performance.

Concordance of a new IMU in different small-sided games and real game tasks in indoor sports

Thu, 31 Oct 2024 00:00:00 +0100

Purpose: The purpose of this study was to analyze the concordance of a new Inertial Measurement Unit (IMU) device called
OLIVER in different specific training tasks and real futsal game.
Methods: 10 elite futsal players competing in First National Division performed most of the typical futsal training tasks
(game possession in 22×20m, 2vs2 in 20×20m, 3vs3, 4vs4 in 28×20m and 4vs4 in 40×20m). Players wore two tracking
devices (OLIVER and WIMU Pro). Data were recorded with specific software systems to compare the concordance of data.
After recording data, descriptive analysis was developed for each training task, as well as a one-way ANOVA to evaluate the
concordance of OLIVER and WIMU devices.
Results: The results reported good agreement for most variables, such as total distance, distance covered in different
partials, as well as meters of accelerations and decelerations at different intensities and maximum speed (P> .05). However,
the distance covered in high-speed running 12.1-18 km/h (m) and the number of runs above 12 km/h reported statistical
differences between OLIVER and WIMU (P< .05) in some of the training tasks.
Conclusion: The OLIVER system and WIMU system shows a high level of concordance in main variables of external load in
different training tasks. OLIVER system is a valid and useful device to monitor external load in indoor sports, both smallsided
games and real games.

The contest for movement education teachers in primary schools: issues of the written exam

Gaetano Raiola, Sara Aliberti, Tiziana D'Isanto, Francesca D'Elia — Thu, 31 Oct 2024 00:00:00 +0100

Purpose: On December 15, 2023, the written test for the first competition for teaching movement education in primary
schools was held, reserved for graduates with a master's degree in Exercise and Sports Science (ESS), of which only 7%
achieved a positive outcome. The aim was twofold: to measure the frequency of errors within each disciplinary field and their
impact on the test result; to identify trends, relationships, and correlations among the variables to analyze and interpret the
reasons for the negative outcome.
Methods: The study involved 100 sport science candidates from 15 Italian regions, recruited nationally through direct
inquiries using personal contacts and social platforms. After obtaining informed consent, candidates were asked to submit
their written tests, omitting identifying data. Spearman's correlation was used to analyze relationships between variables.
Multiple regression was used to assess the impact of errors in each field on the final score.
Results: The biomedical area showed the strongest negative correlation with the final score, followed by the regulatory,
psycho-pedagogical, ESS and English fields. The regression model predicting the final test score based on the errors in each
field was statistically significant (P= .001); particularly, errors in the regulatory field seemed to have a greater impact on
determining the final score.
Conclusions: The study achieved its objective by clarifying that the high rate of negative outcomes was not due to flaws
attributable to the specific training of the graduates in sports sciences, as they performed well in the ESS and psychopedagogical
sections.

Revolutionizing “Text Neck Syndrome” Management: Paradigm Shifting from “Posture Correction” to “Posture Change”

Wissem Dhahbi, Helmi Ben Saad — Thu, 31 Oct 2024 00:00:00 +0100

Purpose: The pervasive use of mobile devices has precipitated an increase in musculoskeletal disorders, notably “text neck
syndrome” (TNS), characterized by neck pain, stiffness, and dysfunction due to prolonged forward head posture. Traditional
management strategies have focused on static posture correction exercises, but recent research advocates for a paradigm
shift towards a dynamic and holistic approach, emphasizing joint-specific mobility and stability. This technical note critiques
the limitations of conventional posture correction and explores the scientific basis for the joint-by-joint approach (JBJA)
training program, which prioritizes mobility restoration to promote sustainable posture change.
Conclusions: The JBJA model highlighted the necessity of addressing the entire kinetic chain, particularly the thoracic spine
and shoulder girdle, to alleviate cervical spine strain. Evidence from recent studies supports the efficacy of this approach
in reducing TNS symptoms and improving overall posture. Implementing posture change into TNS management involves
education, technology-assisted reminders, environmental modifications, and movement-based interventions. This shift not
only addresses the biomechanical imbalances that contribute to TNS but also empowers patients to actively manage their
condition, fostering long-term well-being.

Effect of additional short sprint training on physical performance in adolescent male soccer players: a systematic review and meta-analysis

Elena Mainer Pardos, Okan Kamiş, Rafael Oliveira, Hadi Nobari — Thu, 31 Oct 2024 00:00:00 +0100

Purpose: The aim of this systematic review with meta-analysis (SRMA) was to evaluate the effects of additional short
sprint training with different intervention training programs (i.e. plyometric training, strength training or multidirectional
training) on linear sprint, change of direction speeds (CODS) and jump ability performance in young male soccer players.
Methods: An electronic database search was performed, and 7 articles were included in the meta-analysis.
Results: The players’ mean age ranged from 7.6 to 18.8 years. The duration of combined interventions was from three weeks to
10 months, with training frequency ranging from one to two sessions per week. In general, the results of the performance were
associated with a large and significant reduction in the time of CODS (ES -1.60 (95% CI – 2.33, -.87), Z=4.32 (P< .001)]. Moreover,
the effects on vertical jump height showed a non-significant and small improvement between pre and post-test on the vertical jump
performance [ES .45 (95% CI – .14, .75), Z=2.90 (P= .004)], with an average heterogeneity of I2 = 0%.
Conclusions: The current SRMA suggests that although additional short sprint training may produce improvements in certain
aspects of performance, efficacy varies depending on individual and training-specific factors.

A Systematic Review Evaluating Diagnosis Methods and Treatment Protocols for Achilles Tendinopathy

Karol Jaskulski, Michal Starczewski — Thu, 31 Oct 2024 00:00:00 +0100

Purpose: Diagnosis and treatment protocols for Achilles tendinopathy can be categorized into various groups. However, their
effectiveness varies depending on managing and reducing pain. Therefore, this systematic review analyzes and evaluates the
diagnosis methods and compares treatment protocols' effectiveness for Achilles tendinopathy.
Methods: A systematic review was performed by searching six electronic databases: PubMed, Cochrane Library, Web of
Science, Embase, MEDLINE Ovid, and ProQuest, which were searched for articles on the diagnosis and treatment protocols
for Achilles tendinopathy. The studies that met the inclusion criteria were evaluated, and appropriate data was extracted.
Results: The ten articles that met the inclusion criteria were included in the study. Evidence from the review showed that the
Alfredson protocol had a higher pain nd function improvement compared to the Stanish protocol, with a higher VISA-A score
in the Alfredson than the Stanish protocol. The findings showed that combining the Alfredson eccentric exercise and Stanish
Stretching exercises would significantly improve pain and function for patients with Midportion Achilles tendinopathy. This
result showed that both protocols significantly improve pain and function in Achilles tendinopathy patients. Similarly, HSR
and ECC showed no significant statistical difference in the VISA-A (Victorian Institute of Sport Assessment-Achilles) scores.
Conclusions: HSR is more favorable than ECC, while Alfredson is superior to the Stanish protocol. The VISA-A scores in
Alfredson versus Silbernagel and ECC versus HSR did not provide any significant statistical difference between the groups.
Alfredson and Silbernagel protocols and ECC and HSR show similar results in reducing pain.