Adolescent Swimmers Research Articles

Nutritional Composition of Developed Bars and Their Impact on Work Performance of Adolescent Swimmers’ Girls

With the growing interest in sports nutrition and its impact on athletic performance, understanding the specific needs of adolescent athletes, particularly females, is crucial for optimizing their training and performance outcomes. The three variants of the Protein-rich bar (PB1, PB2, PB3) with the CB were developed by using different ingredients. The research employs a mixed-methods approach, combining nutritional analysis of developed bars with performance assessments among adolescent swimmers’ girls. Firstly, organoleptic evaluation (9-point hedonic scale) was performed on the variants of Protein-rich bar with the CB. Then nutritional analysis involves proximate (moisture, ash, protein, crude fat, crude fiber, CHO), mineral (calcium, iron), as well as antioxidant analysis (DPPH, TPC, vitamin C) assessed on selected variants of Protein-rich bar with the CB. Pre- and post-intervention were done on two groups for 3 months and performance assessments included anthropometric measurement, sit and reach test, hand grip strength test, Nelson hand reaction time test, and Tuttle pulse ratio test. Preliminary findings suggested that the developed bars (PB1) provide a more balanced nutritional profile than the CB. Moisture 10.2±0.66%, ash 3.7±0.27%, protein 22.3±0.74 g, crude fat 13.1±0.41 g, crude fiber 11.5±0.02 g, CHO 39.4±0.19 g, iron 4.4±0.15 mg, calcium 82.4±0.21 mg, DPPH 47.6±0.31%, TPC 53.1±0.11 mg GAE, and vitamin C 11.2±0.19 mg in 100 g respectively in PB1 and significantly difference at (p<0.05). Additionally, the consumption of PB1 bar appears to positively impact higher work performance among adolescent swimmers girls. Overall, this study contributes to the growing body of research on sports nutrition tailored to adolescent athletes, particularly focusing on the nutritional needs of swimmers girls.

Contribution of Ladder Drill and Dryland Circuit Training to 50-meter Freestyle Swimming Speed in 13-to-14 Male Swimmers Aquatic Swimming Club

The objective of this study was to assess the impact of ladder drill and dryland circuit exercises on the pace of 50-meter freestyle swimming in male swimmers aged 13-14 years at the Aquatic Swimming Club in Medan. The researchers employed an experimental approach utilising a pre-experimental design consisting of a single group with pretest and posttest measurements. The sample comprised 8 adolescent male swimmers, aged 13-14 years, who were actively involved in the club. They were recruited via purposive sampling. The study was carried out for a duration of 6 weeks, consisting of 18 training sessions, conducted 3 times a week. Measurements were obtained using 40-meter sprint tests, medicine ball throw tests, and 50-meter freestyle swimming speed tests conducted both before and after the training treatments. The data underwent analysis through normality tests, homogeneity tests, correlation tests, and regression tests. The findings demonstrated that ladder drill training made a noteworthy contribution of 59.29% to enhancing 50-meter freestyle swimming speed. Similarly, dryland circuit training had a substantial impact, accounting for 77.44% of the improvement. Furthermore, when both training methods were combined, they together contributed 62% to the enhancement of swimming speed. The study found that both ladder drill and dryland circuit training have a substantial impact on improving the 50-meter freestyle swimming speed of male swimmers aged 13-14 at the Aquatic Swimming Club in Medan. Additionally, the dryland circuit training was found to have a greater effect than the ladder drill.

The Acute Effects of a Preload Upper-Body Power Exercise on 50-m Freestyle Performance in Youth Swimmers.

Hill, V, Patterson, S, Buckthorpe, M, and Legg, HS. The acute effects of a preload upper-body power exercise on 50-m freestyle performance in youth swimmers. J Strength Cond Res 38(7): 1295-1299, 2024-This study aimed to investigate the acute effects of a medicine ball slam and the optimal recovery time required to induce a postactivation performance enhancement (PAPE) response on 50-meter freestyle swimming performance. Twenty-four (13 female, 11 male) competitive, adolescent swimmers (mean ± SD: age, 16.7 ± 1.2 years; height, 173.3 ± 6.7 cm; mass, 63.1 ± 6.4 kg) participated in a randomized crossover study. After the PAPE intervention (3 × 5 medicine ball slams), subjects had 1-minute, 4-minute, and 8-minute recovery periods before a 50-m maximal freestyle swim. A 1-way repeated-measures ANOVA revealed that different recovery times elicited changes in 50-m performance (F = 12.12, p < 0.0005). After 4 minutes of recovery, 50-m performance was 1.6% (0.47 seconds) faster (95% confidence interval [CI] [0.17-0.77], p < 0.001). When the data were split by sex, after 4 minutes of recovery, 50-m performance was 2% (0.64 seconds) faster for women (95% CI [0.279-0.998], p < 0.001). In conclusion, an upper-body power exercise, before performance, can induce a PAPE response and enhance 50-m freestyle performance after a 4-minute recovery period.

Metrology of Supraspinatus Tendon Thickness in Swimmers with Tendinopathy Using Ultrasound Imaging: An Intra- and Inter-Rater Reliability Study.

Objective: This study aimed to assess the relative and absolute intra- and inter-rater reliability of supraspinatus tendon (SST) thickness. Materials: Thirty adolescent swimmers with supraspinatus (SS) tendinopathy (n = 15) and a control-matched group (n = 15) were evaluated. Tendon thickness was measured according to four different measure procedures, i.e., (1) at 15 mm, (2) at 10, 20, and 30 mm, (3) at 10, 15, and 20 mm, and (4) 5 and 10 mm lateral to the most hyperechogenic reference point of the biceps tendon. Each examiner took two US images for the test measurements with a 10 min rest period. After 30 min, the subjects underwent retest measurements that were also repeated 1 week later. Results: SST thickness was greater in swimmers with SS tendinopathy compared with the matched control group for each procedure and rater (p < 0.001). Intra- and inter-rater reliability was good to excellent (ICC2.3: 0.78-0.98 and 0.83-0.97, respectively) in both groups. The lowest intra- and inter-rater reliability was found in procedures no. 2 and 4 (ICC2.3: 0.78 and 0.83). However, procedure no. 3 was the most reliable with the lowest error rate (ICC2.3: 0.92-0.97; SEM: 0.05-0.10 mm; MDC: 0.14-0.28 mm). Conclusions: The study confirmed the diagnostic value of ultrasound in SS tendinopathy. A multiple-reference-point procedure including a simple methodology (10, 15, and 20 mm from biceps tendon), was defined as the most reliable, expressed by the highest intra- and inter-rater ICCs.

Effects of Dry Land Speed Training on 100-Meter Freestyle Swimming in Adolescent Swimming

Background and Aim: The specific strength development in swimming tends to start at a younger age, so it becomes particularly important to conduct effective Specific strength training during adolescence. It is essential to utilize training methods and means that align with the developmental characteristics of Specific strengths in young swimmers. Thus, this study has developed a specific dry-land training program to enhance the 100-meter freestyle swimming speed of adolescent swimmers. Methods: This study selected 30 male adolescent swimmers from the Shaanxi Provincial Swimming Team and divided them into an experimental group and a control group (15 individuals in each group) based on their 100-meter freestyle speed. Both groups underwent a 12-week training intervention, with 12 training sessions per week, each lasting 2 hours. The total training time and water-based training content were the same for both groups, but the content of dry-land training differed. The experimental group followed a specific dry-land training program, while the control group followed a traditional training program. Comprehensive tests were conducted before and after the 12-week training intervention for both groups, using the physical fitness and test scores of swimmers in the experimental and control groups as research indicators. Experimental and analytical methods, including experimental and statistical methods, were employed to conduct a targeted study on the changes in physical fitness and test scores before and after the training. Results: show that after 12 weeks of training, the scores for both groups are as follows: Pull-ups (Experimental group: P=0.000&lt;0.01, Control group: P=0.777&gt;0.05), Vertical jump (Experimental group: P=0.032&lt;0.05, Control group: P=0.848&gt;0.05), Abdominal muscle endurance (Experimental group: P=0.000&lt;0.01, Control group: P=0.396&gt;0.05), and Back muscle endurance (Experimental group: P=0.004&lt;0.01, Control group: P=0.583&gt;0.05). The post-test results reveal that swimmers in the experimental group performed significantly better in pull-ups, vertical jumps, abdominal muscle endurance, and back muscle endurance compared to the control group. Conclusion: The specialized training program effectively increased the upper limb strength of the participants, with no significant advantage over the traditional training program.

Sleep Quality in Greek Adolescent Swimmers.

The aim of our study was to investigate the relationship between sleep quality and functional indices, swimming distance and gender in adolescent competitive swimmers. Forty-eight adolescent swimmers (boys, n = 22, 15.7 ± 1.0 years and girls, n = 26, 15.1 ± 0.8 years) were included in our study. They were assessed for handgrip strength, respiratory muscle strength and pulmonary function, answered a Pittsburg Sleep Quality Index questionnaire (PSQI), and recorded their anthropometric and morphological characteristics and training load for the last four weeks. The results showed differences between swimming distance and chest circumference difference, between maximal inhalation and exhalation (Δchest) (p = 0.033), PSQI score (p < 0.001), and sleep quality domains for "cannot breathe comfortably" (p = 0.037) and "have pain" (p = 0.003). Binary logistic regression (chi-square = 37.457, p = 0.001) showed that the variables Δchest (p = 0.038, 95% CI: 1.05-6.07) and PSQI score (p = 0.048, 95% CI: 0.1-1.07) remained independent predictors of the swim distance groups. Girls had a lower percentage of predicted values for the maximal inspiratory pressure (p < 0.001), maximal expiratory pressure (p = 0.027), forced expiratory volume within the first second (p = 0.026), forced vital capacity (p = 0.008) and sleep quality domains for "cough or snore loudly" (p = 0.032) compared to boys. A regression analysis showed that the sleep quality score was explained by the six independent variables: respiratory muscle strength (t = 2.177, β = 0.164, p = 0.035), Δchest (t = -2.353, β = -0.17, p = 0.023), distance (t = -5.962, β = -0.475, p < 0.001), total body water (t = -7.466, β = -0.687, p < 0.001), lean body mass (t = -3.120, β = -0.434, p = 0.003), and handgrip (t = 7.752, β = 1.136, p < 0.001). Our findings demonstrate that sleep quality in adolescent swimmers is a multifactorial result of morphometric characteristics, strength and respiratory function.

The Effects of Eccentric Training on Undulatory Underwater Swimming Performance and Kinematics in Competitive Swimmers.

This study aimed to evaluate the effects of a five-week training program on undulatory underwater swimming (UUS) in swimmers and to compare the specific effects prompted by two different training protocols on UUS performance and kinematics. Swimmers (n = 14) were divided into in-water only (WO) (18.61 ± 2.62 years, FINA points: 507 ± 60) and water + dry-land training groups (with conical pulleys) (WD) (18.38 ± 2.67 years, FINA points: 508 ± 83). Three countermovement jumps (CMJ) and three maximal UUS trials were performed before and after a five-week training period. The training program comprised 14 × 30-min sessions. The WO group repeated the same 15-min block twice, while the WD group performed one block of 15 min in the water and the other block on land performing lower limb exercises with conical pulleys. Seven body landmarks were auto-digitalized during UUS by a pre-trained neural network and 21 kinematic variables were calculated. The level of statistical significance was set at p < 0.05. Significant time × group interaction in favour of the WD group was observed for mean vertical toe velocity (p = 0.035, = 0.32). The WD group experienced enhancements in mean and maximum underwater velocity, kick frequency, maximum shoulder angular velocity, as well as mean and maximum vertical toe velocity (p < 0.05). The WO group exhibited an enhancement in CMJ height (p < 0.05). In conclusion, UUS performance was improved in adolescent swimmers after five weeks of specific training, only when combining water and conical pulley exercises. Coaches should include dry-land specific lower limb exercises in addition to in-water training to improve UUS performance.

Sink or Swim? Sleep Patterns in Highly Trained Adolescent Swimmers during the In-Season Phase of Training

Abstract Objectives The aim of this study was to investigate the sleeping patterns of highly-trained adolescent swimmers. Further objectives were to compare subjective and objective measures of sleep and to evaluate the relationship between electronic device use and sleep in this cohort. Methods Fifteen national-level swimmers (age: 16.4 ± 1.0 years) wore wrist actigraphs while completing sleep diaries over a two-week training period. Types of nights were classified as early morning training (≤7am - EARLY), day training (&gt;7am - DAY), and no training (REST). Information on electronic device use before bed and other sleep behaviors was collected via questionnaires. Results Total sleep time (TST) was significantly (p &lt; 0.05) shorter on nights preceding EARLY (5:53 ± 1:06 hour:min) compared with nights preceding DAY (7:40 ± 1:12 hour:min) and REST (7:59 ± 1:19 hour:min). Participants overestimated subjective TST by ∼54 minutes when compared with objectively measured TST (p &lt; 0.05). Discussion Adolescent athletes obtained a greater amount of sleep prior to later training the next day or before rest days, when compared with early morning swim training the next day. Adolescents also overestimated their sleep duration by ∼1 hour per night. There were no significant relationships between electronic device use at night and measured sleep indices.

Effects of post-exercise cold-water immersion on performance and perceptive outcomes of competitive adolescent swimmers

PurposeTo evaluate the effects of repeated use of cold-water immersion (CWI) during a training week on performance and perceptive outcomes in competitive adolescent swimmers.MethodsThis randomized-crossover study included 20 athletes, who received each intervention [CWI (14 ± 1 °C), thermoneutral water immersion (TWI) (27 ± 1 °C) as placebo, and passive recovery (PAS)] three times a week between the land-based resistance training and swim training. The interventions were performed in a randomized order with a 1-week wash-out period. We tested athletes before and after each intervention week regarding swim (100 m freestyle sprints) and functional performance (flexibility, upper and lower body power, and shoulder proprioception). We monitored athlete’s perceptions (well-being, heaviness, tiredness, discomfort and pain) during testing sessions using a 5-item questionnaire. Athlete preferences regarding the interventions were assessed at the end of the study. We used generalized linear mixed models and generalized estimating equations for continuous and categorical variables, respectively (intervention x time).ResultsWe found a time effect for swim performance (p = .01) in which, regardless the intervention, all athletes improved sprint time at post-intervention compared to baseline. There was an intervention effect for pain (p = .04) and tiredness (p = .04), but with no significant post-hoc comparisons. We found no significant effects for other outcomes. All athletes reported a preference for CWI or TWI in relation to PAS.ConclusionThe repeated use of CWI throughout a training week did not impact functional or swim performance outcomes of competitive adolescent swimmers. Perceptive outcomes were also similar across interventions; however, athletes indicated a preference for both CWI and TWI.

The Effect of Coaching Style on Performance of Athletes Through Anxiety as Mediating Variable in Adolescent Swimmers

This study aimed to analyze the effect of the relationship between coach leadership style and the performance achievement of adolescent swimmers through anxiety as a mediator. This study was conducted on 100 adolescent swimmers in the Special Region of Yogyakarta Province who have won at least at the regional level. This type of research was descriptive correlation using the Structural Equation Modeling (SEM) approach with Smart-PLS. The results of this research are the validity test on outer loading (&gt;0.7) and the constructed value on the Fornell-Larcker Criterion is greater than the other construct values (&gt;0.7) and the Cronbach's alpha reliability value (&gt;0.7) means that this instrument is suitable for use for research. The results of the fit model are SRMR or Standardized Root Mean Square value, the value is 0.066 &lt; 0.10 or 0.077 &lt; 0.08 so the model fits the data. Hypothesis results from 1) coaching style and the performance of swimming athletes are P-Values 0.001, 2) the relationship between coaching style and anxiety, P-Values 0.002, 3) the relationship between anxiety and the performance of swimming athletes, P-Values 0.000, 4) the relationship between coaching style and the performance of swimming athletes through anxiety P-Values 0.021. Therefore, four hypotheses can be accepted. In conclusion, differences in types of coaching styles, either directly or indirectly, will influence athletes' achievement orientation and performance. Keywords: Coaching Style, Anxiety, Performance Achievement, Swimmer

Glycerophospholipids in Red Blood Cells Are Associated with Aerobic Performance in Young Swimmers.

This study aimed to characterize the composition of lipids in the red blood cells (RBCs) of adolescent swimmers and correlate this lipidome with the aerobic performance of the athletes. Five experimental assessments were performed by 37 adolescent swimmers. During the first session, the athletes went to the laboratory facility for venous blood sampling. The critical velocity protocol was conducted over the 4 subsequent days to measure aerobic performance (CV), comprising maximal efforts over distances of 100, 200, 400, and 800 m in a swimming pool. RBCs were obtained and extracted for analysis using the liquid chromatography-high resolution mass spectrometry untargeted approach. A total of 2146 ions were detected in the RBCs, of which 119 were identified. The enrichment pathway analysis indicated intermediary lipids in the glycerophospholipid, glycerolipid, sphingolipid, linoleic acid, and alpha-linolenic metabolisms, as well as pentose and glucuronate interconversions. A significant impact of the intermediary lipids was observed for the glycerophospholipid metabolism, including phosphatidylethanolamine (PE), phosphatidylcholine (PC), 1-acyl-sn-glycero-3-phosphocholine, sn-glycerol 3-phosphate, and phosphatidic acid. Inverse and significant associations were observed for PE 18:2/18:3 (r = -0.39; p = 0.015), PC 18:3/20:0 (r = -0.33; p = 0.041), and phosphatidic acid 18:0/0:0 (r = -0.47; p = 0.003) with aerobic performance. Swimmers who exhibited higher levels of aerobic performance also had the lowest abundance of PE, PC, and phosphatidic acid.

Investigating Nutrition Literacy Levels among Adolescent Swimmers

Investigating Nutrition Literacy Levels among Adolescent Swimmers

Does scapular dysfunction alter scapular muscles activity and kinematics during swim stroke motion on adolescent swimmers?

ABSTRACT Scapular dyskinesis (SD) indicates dysfunction of the scapular muscle activity during the arm elevation, resulting in altered scapular kinematics. This study examined whether SD alters scapular muscle activity and kinematics during swim stroke motion. Seventeen swimmers (mean age: 13 ± 1 years) were divided into SD (n = 8) and control (n = 9) groups. Scapular muscle activity (the upper, middle, and lower trapezius and the serratus anterior muscle) and kinematics data were collected and time-normalised (0–100%) during swim stroke motion by swim-bench on land. Scapular kinematics were calculated for upward rotation, internal rotation, posterior tilt, and arm elevation angles. To compare patterns of muscle activity and kinematics with and without SD, statistical parametric mapping unpaired t-test was used. The scapular upward rotation angle was decreased in SD compared to control in the 0–10% of the swim stroke phase (p = 0.041, t* = 3.018), and the internal rotation angle was increased in 0–15% of the phase (p = 0.033, t* = 2.994). Scapular posterior tilt and muscle activity showed no significant differences. These results suggested that SD altered scapular upward rotation and internal rotation at the initial phase of the swim stroke motion in adolescent swimmers and might potentially provoke a risk of subacromial impingement.

Effects of anthropometrics, thrust, and drag on stroke kinematics and 100 m performance of young swimmers using path-analysis modeling.

The aim of this study was to understand the interactions between anthropometric, kinetic, and kinematic variables and how they determine the 100 m freestyle performance in young swimmers. Twenty-five adolescent swimmers (15 male and 10 female, aged 15.75 ± 1.01 years) who regularly participated in regional and national competitions were recruited. The 100 m freestyle performance was chosen as the variable to be predicted. A series of anthropometric (hand surface area-HSA), kinetic (thrust and active drag coefficient (CDA )), and kinematic (stroke length (SL); stroke frequency (SF), and swimming speed) variables were measured. Structural equation modeling (via path analysis) was used to develop and test the model. The initial model predicted performance with 90.1% accuracy. All paths were significant (p < 0.05) except the thrust-SL. After deleting this non-significant path (thrust-SL) and recalculating, the model goodness-of-fit improved and all paths were significant (p < 0.05). The predicted performance was 90.2%. Anthropometrics had significant effects on kinetics, which had significant effects on kinematics, and consequently on the 100 m freestyle performance. The cascade of interactions based on this path-flow model allowed for a meaningful prediction of the 100 m freestyle performance. Based on these results, coaches and swimmers should be aware that the swimming predictors can first meaningfully interact with each other to ultimately predict the 100 m freestyle performance.

Psychophysiological Effects of Slow-Paced Breathing on Adolescent Swimmers' Subjective Performance, Recovery States, and Control Perception.

This study examined the effect of a Slow-Paced Breath (i.e., 6 breaths per minute) without Biofeedback (SPB-NoHRVB) protocol on semi-elite adolescent swimmers' psychological and physiological states during a seven-week ecological training period. A linear mixed-effects multilevel regression analysis approach was used with 13 adolescent national-level swimmers. Athletes were randomly assigned to an intervention group (n = 7) and a control group (n = 6). Seven waves of assessments were completed weekly during a seven-week training preparation in ecological conditions. During the protocol, swimmers completed subjective quantitative measures (RESTQ-36-R-Sport; cognitive perceived stress and control states about the training process, training subjective performance, and subjective internal training load) and physiological heart rate (HR) (HR of exercise, absolute and normalized HR recovery during the first 60 s of recovery; HRR60 and nHRR60) and heart rate variability (HRV) (MeanRR, RMSSD, LFnu and HFnu, LF/HF ration) tests (through a submaximal heart rate (5'-5' test) once a week. Results revealed that the SPB-NoHRVB protocol significantly predicts biopsychosocial recovery states, cognitive perception of control, and training subjective performance (i.e., a significant effect of the SPB-NoHRVB protocol with the dependent variables simple time trajectories). However, no significant effects were found for biopsychosocial stress scales, cognitively perceived stress, HR, or HRV markers. Our results suggest that SPB-NoHRVB induces simple evolutions over time for crucial variables in athletes' adaptation to the training process (i.e., cognitive appraisals and biopsychosocial states). In contrast, it highlights that SPB-NoHRVB does not induce better stress states. This specific effect on the resource component is an exciting result that will be discussed in the manuscript.

Investigating the interrelationships among food habits, sports nutrition knowledge, and perceived barriers to healthy eating: a study of adolescent swimmers.

This cross-sectional study aims to explore the relationships between food habits, perceived barriers to healthy eating, and sports nutrition knowledge among adolescent swimmers. The study focuses on understanding how these factors interact and influence dietary choices in young athletes. A cohort of 52 adolescent swimmers aged 12-18 from Al Hussein Youth Club in Al-Hussein Sport City participated in the study. Data were collected through surveys assessing food habits, perceived barriers to healthy eating, and sports nutrition knowledge. Pearson Correlation analysis was employed to examine associations between variables, and stepwise regression analysis was used to identify predictors of food habits. The analysis revealed a significant positive association between food habits and sports nutrition knowledge (r = 0.393, p = 0.004). Knowledge emerged as a significant positive predictor of food habits (β = 0.393, p = 0.004), highlighting the influential role of sports nutrition knowledge in shaping the dietary choices of adolescent swimmers. However, the introduction of Barriers lacked significance, and individual predictors did not reach statistical significance. These findings underscore the importance of targeted interventions aimed at enhancing nutritional education among adolescent swimmers. Understanding the interplay between knowledge, barriers, and food habits provides valuable insights into the complex dynamics that influence the dietary choices of young athletes. Addressing these factors through tailored educational programs can promote healthier eating habits and optimize performance among adolescent swimmers. This study highlights the critical role of sports nutrition knowledge in shaping the dietary behaviors of adolescent swimmers. By addressing knowledge gaps and overcoming perceived barriers, targeted interventions can help improve food habits and enhance the overall health and performance of young athletes.

The influence of anthropometric characteristics on swimming speed in adolescent swimmers

Swimming speed depends on anthropometric characteristics, biomechanics factors, physical fitness, physiological components, and genetics. Therefore, this study aimed to identify which anthropometric characteristics influence swimming speed in adolescent competitive swimmers. Thirty-eight male swimmers (aged 16.94 ± 0.8 years; body height: 178.3 ± 5.4 cm; body weight 67.7 ± 9.6 kg) and thirty-five female swimmers (aged 17.12 ± 0.7 years; body height: 175.1 ± 6.6 cm; body weight 59.9 ± 7.1 kg) participated in the study. All swimmers have competed at the national level in Serbia for at least three years and have at least five years of training experience. Fifteen variables were measured: arm length, hand length, leg length, foot length, seat height, wrist diameter, ankle joint diameter, elbow diameter, chest circumference, triceps skinfold, forearm skinfold, abdominal skinfold, subscapular skinfold, thigh skinfold, calf skinfold. The measurements were taken by the Martin anthropometer, Omron digital scale BF511, and John Bull caliper. Swimming speed was measured during 50-m and 100-m front crawl swimming. Multiple regression analysis revealed that arm length, wrist diameter, and chest circumference, all together, accounted for 77% of 100-m front crawl swimming speed in male swimmers, while abdominal skinfold accounted for 90% of 100-m front crawl swimming speed in female swimmers. Results showed that anthropometric characteristics could not account for adolescent swimmers' 50-m front crawl swimming speed. However, anthropometric characteristics can influence the result in swimming (100-m front crawl swimming speed) in adolescents and thus should be considered a diagnostic tool in selecting young swimmers.

Reliability of a semi-tethered front crawl sprint performance test in adolescent swimmers.

This study aimed to evaluate the test-retest reliability of a sprint performance test with semi-tethered front crawl swimming to indirectly assess the current potential to perform at maximal anaerobic effort in adolescent swimmers. Eight adolescent swimmers participated in this study (gender: females (n = 4) aged 13.0 ± 0.8 years, body height 1.6 ± 0.0m, body mass 50.1 ± 4.5kg; and males (n = 4) aged 13.3 ± 1.3 years, body height 1.7 ± 0.1m, body mass 59.0 ± 8.2kg. The testing protocol consisted of two trials of 25m semi-tethered front crawl swimming with maximal effort and with 1kg resisted isotonic load. Velocity data were recorded automatically by the 1080 Sprint device for 15m (between 3m and 18m). The Fast Fourier Transform algorithm filtered raw instantaneous swimming velocity data in distance (time) function. A third-degree polynomial was used to extract the individual velocity profile, from which the following variables were chosen for test-retest reliability and the assessment of sprint performance: ttrial15, vmax, vmin, tvto max, tvat max, Dto vmax, Dat vmax, fatigue index. Parameters such as vmax, vmin, and ttrial15 were estimated from swimming velocity profiles and considered as reliable. The CV showed low variance <5%; while ICC2,1 demonstrated respectively good (ICC2,1: 0.88), very good (ICC2,1: 0.95), and excellent (ICC2,1: 0.98) rate of relative reliability; and the Bland-Altman index revealed an acceptable agreement (LoA ≤5%) between two measurements. The sprint performance test based on semi-tethered front crawl swimming confirmed that ttrial15, vmax, and vmin were reliable variables to indirectly indicate a potential to perform the maximal anaerobic effort among adolescent swimmers. The evaluation of the swimming velocity profiles allows coaches to monitor the adaptive changes of performance during the training process.

Test–retest reliability of the power push-up test in adolescent swimmers: force plate-derived parameters’ reliability of power push-up test in adolescent swimmers

Test–retest reliability of the power push-up test in adolescent swimmers: force plate-derived parameters’ reliability of power push-up test in adolescent swimmers

Development and Interplay of Metabolic and Mechanical Performance Determinants Over an Annual Training Period in Adolescent National-Level Squad Swimmers.

The study examined the longitudinal interplay of anthropometric, metabolic, and neuromuscular development related to performance in adolescent national-level swimmers over 12months. Seven male and 12 female swimmers (14.8 [1.3]y, FINA [International Swimming Federation] points 716 [51]) were tested before (T0) and after the preparation period (T1), at the season's peak (T2), and before the next season (T3). Anthropometric (eg, fat percentage) and neuromuscular parameters (squat and bench-press load-velocity profile) were assessed on dry land. Metabolic (cost of swimming [C], maximal oxygen uptake [V˙O2peak], and peak blood lactate [bLapeak]) and performance (sprinting speed [vsprint] and lactate thresholds [LT1 and 2]) factorswere determined using a 500-m submaximal, 200-m all-out, 20-second sprint, and incremental test (+0.03m·s-1, 3min), respectively, in front-crawl swimming. vsprint (+0.6%) and LT1 and 2 (+1.9-2.4%) increased trivially and slightly, respectively, from T0 to T2 following small to moderate strength increases (≥+10.2%) from T0 to T1 and V˙O2peak (+6.0%) from T1 to T2. Bench-press maximal strength and peak power correlated with vsprint from T0 to T2 (r ≥ .54, P < .05) and LT2 at T1 (r ≥ .47, P < .05). Changes in fat percentage and V˙O2peak (T2-T1 and T3-T2, r ≤ -.67, P < .01) and C and LT2 (T2-T0, r = -.52, P = .047) were also correlated. Increases in strength and V˙O2peak from preparation to the competition period resulted in improved sprint and endurance performance. Across the season, upper-body strength was associated with vsprint and LT2, although their changes were unrelated.