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This study aimed to compare changes in swimmers' performance, biomechanical variables, and strength asymmetries within two successive training years. Eight competitive age-group swimmers (four males and four females; age: 14.8 ± 1.3 years) were tested before and after the same 12-week mesocycle period within two successive years (Year-1, Year-2). The swimmers were timed in 50, 200, and 400 m, and the stroke rate (SR), stroke length (SL), and stroke index (SI) were calculated. SI was calculated by the product of SL with swimming speed. Dryland shoulder isometric strength (ISO), hand grip isometric strength test (HG), and in-water maximum 30 s tethered swimming force (TF) were evaluated. The asymmetry index was calculated using ISO, HG, and TF tests as [(Fd − Fnd)/0.5 × (Fd + Fnd)] × 100, where Fd is strength in the dominant hand and Fnd is strength in the non-dominant hand. Performance time improved in 200 and 400 m, while the asymmetry indices calculated by the ISO, HG, and TF tests were similar after 12 weeks of training in both Year-1 and Year-2 (p = 0.01). Changes (Δ) in HG strength asymmetries correlated with Δ in 200 and 400 m in Year-2 (r = 0.78–0.87, p = 0.01). The asymmetry index does not change after two successive years of training but may be connected to performance changes in 200 and 400 m front crawl. [ABSTRACT FROM AUTHOR]

Purpose: To examine the effect of dryland training during an 11-week lockdown period due to COVID-19 on swimming performance. Methods: Twelve competitive swimmers performed 50- and 300-m maximum-effort tests in their preferred stroke and 200-, 400-, and four 50-m front crawl sprints (4 × 50 m) before and after the lockdown period. Critical speed as an index of aerobic endurance was calculated using (1) 50-, 300-, and (2) 200-, 400-m tests. Blood lactate concentration was measured after the 400- and 4 × 50-m tests. To evaluate strength-related abilities, the dryland tests included handgrip and shoulder isometric strength. Tethered swimming force was measured during a 10-second sprint. During the lockdown period, dryland training was applied, and the session rating of perceived exertion training (sRPE) load was recorded daily. Results: sRPE training load during the lockdown was decreased by 78% (16%), and critical speed was reduced 4.7% to 4.9% compared to prelockdown period (P <.05). Performance time in 200, 300, and 400 m deteriorated 2.6% to 3.9% (P <.05), while it remained unaltered in 4 × 50- and 50-m tests (P >.05). Tethered force increased 9% (10%) (P <.01), but handgrip and shoulder isometric force remained unaltered (P >.05). Blood lactate concentration decreased 19% (21%) after the 400-m test and was unchanged following the 4 × 50-m tests (P >.05). Conclusions: Performance deterioration in the 200, 300, and 400 m indicates reduced aerobic fitness and impaired technical ability, while strength and repeated-sprint ability were maintained. When a long abstention from swimming training is forced, dryland training may facilitate preservation in short-distance but not middle-distance swimming performance. [ABSTRACT FROM AUTHOR]

The aim of this study was to identify the relationship between dry-land and in-water strength with performance and kinematic variables in short-distance, middle-distance, and repeated sprint swimming. Fifteen competitive swimmers applied a bench press exercise to measure maximum strength (MS), maximum power (P), strength corresponding to P (F@P), maximum velocity (MV), and velocity corresponding to P (V@P) using F–V and P–V relationships. On a following day, swimmers performed a 10 s tethered swimming sprint (TF), and impulse was measured (IMP). On three separate days, swimmers performed (i) 50 and 100 m, (ii) 200 and 400 m, and (iii) 4 × 50 m front crawl sprint tests. Performance time (T), arm stroke rate (SR), arm stroke length (SL), and arm stroke index (SI) were calculated in all tests. Performance in short- and middle-distance tests and in 4 × 50 m training sets were related to dry-land MS, P, TF, and IMP (r = 0.51–0.83; p < 0.05). MS, P, and TF were related to SR in 50 m and SI in 50 and 100 m (r = 0.55–0.71; p < 0.05). A combination of dry-land P and in-water TF variables explains 80% of the 50 m performance time variation. Bench press power and tethered swimming force correlate with performance in short- and middle-distance tests and repeated sprint swimming. [ABSTRACT FROM AUTHOR]

Purpose: To examine the effects of active and passive recovery of various durations after a 100-m swimming test performed at maximal effort. Methods: Eleven competitive swimmers (5 males, 6 females, age: 17.3 ± 0.6 y) completed two 100-m tests with a 15-min interval at a maximum swimming effort under three experimental conditions. The recovery between tests was 15 min passive (PAS), 5 min active, and 10 min passive (5ACT) or 10 min active and 5 min passive (10ACT). Self-selected active recovery started immediately after the first test, corresponding to 60 ± 5% of the 100-m time. Blood samples were taken at rest, 5, 10, and 15 min after the first as well as 5 min after the second 100-m test for blood lactate determination. Heart rate was also recorded during the corresponding periods. Results: Performance time of the first 100 m was not different between conditions (P > .05). The second 100-m test after the 5ACT (64.49 ± 3.85 s) condition was faster than 10ACT (65.49 ± 4.63 s) and PAS (65.89 ± 4.55 s) conditions (P < .05). Blood lactate during the 15-min recovery period between the 100-m efforts was lower in both active recovery conditions compared with passive recovery (P < .05). Heart rate was higher during the 5ACT and 10ACT conditions compared with PAS during the 15-min recovery period (P < .05). Conclusion: Five minutes of active recovery during a 15-min interval period is adequate to facilitate blood lactate removal and enhance performance in swimmers. Passive recovery and/or 10 min of active recovery is not recommended. [ABSTRACT FROM AUTHOR]

Purpose. The purpose of the study was to compare the effectiveness of 2 different dry-land active warm-up protocols on 50-m front-crawl swimming performance, biomechanical variables (stroke rate, stroke length, and stroke index), rate of perceived exertion, and exercise heart rate in swimmers of both genders. Methods. The total of 10 male and 9 female national-level swimmers completed a standardized 1000-m in-water warm-up protocol followed by a 30-min transition phase and a 50-m front-crawl time-trial. During this 30-min period, each swimmer executed, on different occasions, a protocol consisting of either a dynamic stretching routine (stretch) or a power exercise circuit (power) of equal duration (~ 5 min) in a randomized sequence. A control condition (control) including a passive recovery strategy after the in-water warm-up protocol was also analyzed. Results. An improvement in 50-m time-trial performance was demonstrated in male swimmers after executing the power protocol (p = 0.034), while in female swimmers a trend towards faster performance times was revealed after the stretch protocol (p = 0.064). Stroke index was improved after the stretch routine only in female swimmers (p = 0.010). Stroke rate, stroke length, rate of perceived exertion, and exercise heart rate showed no differences among all the 3 conditions in either gender (p > 0.05). Conclusions. Male and female swimmers respond differently to a power or a dynamic stretching protocol. In addition, the variation in responses to different warm-up conditions highlights the importance of individualizing the dry-land warm-up procedure to promote maximum performance during 50-m front-crawl swimming events. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine the metabolic responses during submaximal swimming with self-selected normal breathing (N) and prolonged expiration along with reduced frequency breathing (RB). Ten male swimmers (age: 23.1 ± 2.2 years; VO2max: 47.3 ± 7.2 ml · kg−1· min−1) performed 75-, 100-, 175-, 200-, 275-, 300-, 375- and 400-m trials with N and RB at intensity corresponding to 90% of the critical speed. In RB condition, all trials longer than 75 m were interspersed with 25 m of self-selected N in regular intervals. In RB, oxygen saturation during recovery was decreased compared to starting values after 75, 100, 175, 275 and 375 m (78–91%,P < 0.05), while it remained unchanged after all trials in N condition (98 ± 2%,P > 0.05). Lactate concentration was higher in RB than in N after 400 m (4.3 ± 1.5 vs. 3.3 ± 1.7 mmol · l−1,P < 0.05). During recovery after the 375-m trial, partial pressure of carbon dioxide was increased and pH was decreased in RB compared to N condition. Prolonged expiration along with RB provokes severe hypoxemia during the recovery period after swimming, which is restored with self-selected N during submaximal swimming. [ABSTRACT FROM PUBLISHER]

The Critical velocity (Vcrit) represents a holistic swimming fatigue threshold and critical stroke rate is thought to coincide with Vcrit. Whether Vcrit, and in-turn critical stroke rate, also represent an inspiratory muscle fatigue threshold is not known. Following the determination of Vcrit and critical stroke rate via a two-parameter 200-m and 400-m model, 17 well-trained competitive swimmers (9 males and 8 females) undertook three experimental 200-m front crawl (FC) swims on separate occasions. One experimental swim corresponded to Vcrit, one was 5% slower than Vcrit (Vcrit5%+) and one 5% faster (Vcrit5%-) than Vcrit. Swim time, inspiratory and expiratory mouth pressure (PImax and PEmax, respectively), stroke rate, stroke length and breathing frequency were recorded during each experimental swim and were compared between swims as well as between genders. Baseline PImax and PEmax did not differ between experimental swims or genders. Although PEmax decreased significantly by a similar magnitude after each swim (range 5-8%), PImax was significantly lower in response to swimming at Vcrit (7%) and Vcrit5%- (22%) thus indicating inspiratory muscle fatigue. However, the difference in magnitude between velocities was not significant. Only stroke rate and relative swimming velocity were significantly related to the fall in PImax and no correlations were observed between PEmax and any other variable. The development of inspiratory muscle fatigue at and above Vcrit is consistent with substantial swim induced metabolic strain with the response similar between males and females. Our data suggest that Vcrit represents a FC inspiratory muscle fatigue threshold when using this two-parameter Vcrit model. [ABSTRACT FROM AUTHOR]

The study examined the changes of training load and physiological parameters in relation to competitive performance during a period leading to a national championship. The training content of twelve swimmers (age: 14.2±1.3 yrs) was recorded four weeks before the national championship (two weeks of normal training and two weeks of the taper). The training load was calculated: i) by the swimmer's session-RPE score (RPE-Load), ii) by the training intensity levels adjusted after a 7x200-m progressively increasing intensity test (LA-Load). Swimmers completed a 400-m submaximal intensity test, a 15 s tethered swimming and hand-grip strength measurements 34-35 (baseline: Test 1), 20-21 (before taper: Test 2) and 6-7 (Test 3) days before the national championship. Performance during the national championship was not significantly changed compared to season best (0.1±1.6%; 95% confidence limits: -0.9, 1.1%; Effect Size: 0.02, p=0.72) and compared to performance before the start of the two-week taper period (0.9±1.7%; 95% confidence limits: 0.3, 2.1%; Effect size: 0.12, p=0.09). No significant changes were observed in all measured physiological and performance related variables between Test 1, Test 2, and Test 3. Changes in RPE-Load (week-4 vs. week-1) were correlated with changes in performance (r=0.63, p=0.03) and the RPE-Load was correlated with the LALoad (r=0.80, p=0.01). The estimation of the session-RPE training load may be helpful for taper planning of young swimmers. Increasing the difference between the normal and last week of taper training load may facilitate performance improvements. [ABSTRACT FROM AUTHOR]

The article presents the results of a study which compared repeated sprint swimming performances using various types of recovery from fatigue. An overview of related previous research is provided, along with details of the experimental protocol, which used low-intensity, high-intensity, and passive recovery methods.

The effect of active and passive recovery on repeated-sprint swimming bouts was studied in eight elite swimmers. Participants performed three trials of two sets of front crawl swims with 5 min rest between sets. Set A consisted of four 30-s bouts of high-intensity tethered swimming separated by 30 s passive rest, whereas Set B consisted of four 50-yard maximal-sprint swimming repetitions at intervals of 2 min. Recovery was active only between sets (AP trial), between sets and repetitions of Set B (AA trial) or passive throughout (PP trial). Performance during and metabolic responses after Set A were similar between trials. Blood lactate concentration after Set B was higher and blood pH was lower in the PP (18.29 ± 1.31 mmol · l-1 and 7.12 ± 0.11 respectively) and AP (17.56 ± 1.22 mmol · l-1 and 7.14 ± 0.11 respectively) trials compared with the AA (14.13 ± 1.56 mmol · l-1 and 7.23 ± 0.10 respectively) trial (P < 0.01). Performance time during Set B was not different between trials (P > 0.05), but the decline in performance during Set B of the AP trial was less marked than in the AA or PP trials (main effect of sprints, P < 0.05). Results suggest that active recovery (60% of the 100-m pace) could be beneficial between training sets, and may compromise swimming performance between repetitions when recovery durations are short (< 2 min). [ABSTRACT FROM AUTHOR]

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Background: The purpose of this study was to compare physiological responses during continuous and intermittent swimming at intensity corresponding to critical speed (CS: slope of the distance vs. time relationship using 200 and 400-m tests) with maximal lactate steady state (MLSS) in children and adolescents. Methods: CS and the speed corresponding to MLSS (sMLSS) were calculated in ten male children (11.5 ± 0.4 years) and ten adolescents (15.8 ± 0.7 years). Blood lactate concentration (BL), oxygen uptake ( V · O2), and heart rate (HR) at sMLSS were compared to intermittent (10 × 200-m) and continuous swimming corresponding to CS. Results: CS was similar to sMLSS in children (1.092 ± 0.071 vs. 1.083 ± 0.065 m·s−1; p = 0.12) and adolescents (1.315 ± 0.068 vs. 1.297 ± 0.056 m·s−1; p = 0.12). However, not all swimmers were able to complete 30 min at CS and BL was higher at the end of continuous swimming at CS compared to sMLSS (children: CS: 4.0 ± 1.8, sMLSS: 3.4 ± 1.5; adolescents: CS: 4.5 ± 2.3, sMLSS: 3.1 ± 0.8 mmol·L−1; p < 0.05). V · O2 and HR in continuous swimming at CS were not different compared to sMLSS (p > 0.05). BL, V · O2 and HR in 10 × 200-m were similar to sMLSS and no different between groups. Conclusion: Intermittent swimming at CS presents physiological responses similar to sMLSS. Metabolic responses of continuous swimming at CS may not correspond to MLSS in some children and adolescent swimmers. [ABSTRACT FROM AUTHOR]