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Raineteau Y, Nicolas G, Bideau B, Bideau N, Pla R. Associations between load-velocity profiling and race parameters of elite swimmers in the 100 and 200m freestyle events. Front Sports Act Living 2023; 5:1326106. [PMID: 38162699 PMCID: PMC10757606 DOI: 10.3389/fspor.2023.1326106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2023] [Accepted: 11/30/2023] [Indexed: 01/03/2024] Open
Abstract
Introduction Improving swimming performance involves assessments of biomechanical variables of the stroke, and it can be achieved using semi-tethered swimming tests. The aim of this study was thus to investigate the associations between load-velocity (L-V) profiles, from a semi-tethered swimming protocol and race variables in the 100 m and 200 m freestyle events. Methods Eight swimmers completed a L-V profiling protocol consisting of four sprints (25 m, 25 m, 20 m, 15 m) against increasing loads (0.1, 2.0, 4.0, 6.0 kg respectively) with complete recovery between repetitions (>5 min). The L-V linear regression was used to estimate maximal velocity (V0) and body mass normalized load (rL0). Race variables such as clean swimming speed (V), stroke rate (SR), distance per cycle (SL) and stroke index (SI) were assessed from video analysis of 100 m and 200 m freestyle events taking place 3-4 days after the L-V protocol. Results L-V results showed high levels of speed (mean ± SD: 1.87 ± 0.04 m/s) and heavy maximal relative loads (mean ± SD: 38.5 ± 6.51 as % of body mass). Swimmers also achieved high-level performances in the 100 m (mean ± SD time: 51.95 ± 0.75 s) and the 200 m (mean ± SD time: 113.85 ± 2.67 s). For the 100 m events, the maximal relative load showed strong correlation with performance (r = 0.63) whereas trivial correlation was observed for the 200 m events (r = 0.12). SR on the 100 m and the 200 m also showed very strong association with rL0 (r = 0.83) and a strong association with V0 (r = 0.68) respectively. Conclusion The relationships between L-V variables and race variables depend on the distance of the event. However, L-V variables seem to be less related to SR and SL evolutions for the 100 m than in the 200 m event. Moreover, L-V profiles tend to be more related to the 100 m than 200 m freestyle performance. L-V profile should be interpreted taking into consideration the specific physiological and biomechanical constraints of the main events of the swimmer.
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Affiliation(s)
- Yannis Raineteau
- M2S Laboratory—Laboratoire Mouvement Sport Santé, Université Rennes 2, Rennes, France
- Optimization service, Fédération Française de Natation, Clichy, France
| | - Guillaume Nicolas
- M2S Laboratory—Laboratoire Mouvement Sport Santé, Université Rennes 2, Rennes, France
- MIMETIC-Team, INRIA Rennes Bretagne Atlantique, Rennes, France
| | - Benoit Bideau
- M2S Laboratory—Laboratoire Mouvement Sport Santé, Université Rennes 2, Rennes, France
- MIMETIC-Team, INRIA Rennes Bretagne Atlantique, Rennes, France
| | - Nicolas Bideau
- M2S Laboratory—Laboratoire Mouvement Sport Santé, Université Rennes 2, Rennes, France
- MIMETIC-Team, INRIA Rennes Bretagne Atlantique, Rennes, France
| | - Robin Pla
- Optimization service, Fédération Française de Natation, Clichy, France
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Szczepan S, Wróblewska Z, Klich S, Michalik K, Gonjo T, Olstad BH, Rejman M. Reliability of a semi-tethered front crawl sprint performance test in adolescent swimmers. Front Physiol 2023; 14:1260346. [PMID: 38156067 PMCID: PMC10753824 DOI: 10.3389/fphys.2023.1260346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 11/29/2023] [Indexed: 12/30/2023] Open
Abstract
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 ± 0.0 m, body mass 50.1 ± 4.5 kg; and males (n = 4) aged 13.3 ± 1.3 years, body height 1.7 ± 0.1 m, body mass 59.0 ± 8.2 kg. The testing protocol consisted of two trials of 25 m semi-tethered front crawl swimming with maximal effort and with 1 kg resisted isotonic load. Velocity data were recorded automatically by the 1080 Sprint device for 15 m (between 3 m and 18 m). 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.
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Affiliation(s)
- Stefan Szczepan
- Department of Swimming, Faculty of Physical Education and Sport, Wroclaw University of Health and Sport Sciences, Wroclaw, Poland
| | - Zofia Wróblewska
- Faculty of Pure and Applied Mathematics, Wroclaw University of Science and Technology, Wroclaw, Poland
| | - Sebastian Klich
- Department of Paralympic Sport, Faculty of Physical Education and Sport Science, Wroclaw University of Health and Sport Sciences, Wroclaw, Poland
| | - Kamil Michalik
- Department of Human Motor Skills, Faculty of Physical Education and Sport Sciences, Wroclaw University of Health and Sport Sciences, Wroclaw, Poland
| | - Tomohiro Gonjo
- Institute for Life and Earth Sciences, School of Energy, Geoscience, Infrastructure and Society, Heriot-Watt University, Edinburgh, United Kingdom
| | - Bjørn Harald Olstad
- Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway
| | - Marek Rejman
- Department of Swimming, Faculty of Physical Education and Sport, Wroclaw University of Health and Sport Sciences, Wroclaw, Poland
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Gonjo T, Njøs N, Eriksrud O, Olstad BH. The Relationship Between Selected Load-Velocity Profile Parameters and 50 m Front Crawl Swimming Performance. Front Physiol 2021; 12:625411. [PMID: 33679439 PMCID: PMC7933527 DOI: 10.3389/fphys.2021.625411] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 02/01/2021] [Indexed: 11/29/2022] Open
Abstract
The purpose of the present study was to establish relationships between sprint front crawl performance and a swimming load-velocity profile. Fourteen male national-level swimmers performed 50 m front crawl and semi-tethered swimming with three progressive loads. The 50 m performance was recorded with a multi-camera system, with which two-dimensional head displacement and the beginning of each arm-stroke motion were quantified. Forward velocity (V50m), stroke length (SL) and frequency (SF) were quantified for each cycle, and the mean value of all cycles, excluding the first and last cycles, was used for the analysis. From the semi-tethered swimming test, the mean velocity during three stroke cycles in mid-pool was calculated and plotted as a function of the external load, and a linear regression line expressing the relationship between the load and velocity was established for each swimmer. The intercepts between the established line and the axes of the plot were defined as theoretical maximum velocity (V0) and load (L0). Large to very large correlations were observed between V50m and all variables derived from the load-velocity profiling; L0 (R = 0.632, p = 0.015), L0 normalized by body mass (R = 0.743, p = 0.002), V0 (R = 0.698, p = 0.006), and the slope (R = 0.541, p < 0.046). No significant relationships of SL and SL with V50m and the load-velocity variables were observed, suggesting that each swimmer has his own strategy to achieve the highest swimming velocity. The findings suggest that load-velocity profiling can be used to assess swimming-specific strength and velocity capabilities related to sprint front crawl performance.
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Affiliation(s)
- Tomohiro Gonjo
- Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway
| | - Nikolai Njøs
- Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway
| | - Ola Eriksrud
- Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway
| | - Bjørn H Olstad
- Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway
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Olstad BH, Gonjo T, Njøs N, Abächerli K, Eriksrud O. Reliability of Load-Velocity Profiling in Front Crawl Swimming. Front Physiol 2020; 11:574306. [PMID: 33071829 PMCID: PMC7538691 DOI: 10.3389/fphys.2020.574306] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 08/26/2020] [Indexed: 11/13/2022] Open
Abstract
The purposes of this study were to establish test-retest reliability of calculating load-velocity profiles in front crawl swimming using five and three different external loads, and if outcome results were comparable between calculation methods for monitoring performance over time. Fifteen swimmers at either national or international competition level (seven females and eight males) participated in this study. The subjects performed 25 m of semi-tethered swimming with maximal effort with five progressive loads (females 1, 2, 3, 4, and 5 kg and males 1, 3, 5, 7, and 9 kg) as well as 50 m maximal front crawl on 2 different days. The mean velocity during three stroke cycles in mid-pool was calculated and plotted as a function of the external load. Relationship between the load and velocity was expressed by a linear regression line and established for each swimmer. The intercepts between the axes of the plot and the established regression line were defined as theoretical maximum velocity (V0) and load (L0). In addition, L0 was also expressed as a percentage of body mass (rL0). The coefficient of determination (R2) and the slope (Slv) of the linear load-velocity relationship were calculated. The intra-class correlation coefficient (ICC) showed excellent agreement (ICC ≥0.902) for all variables. The coefficient of variation was ≤3.14% and typical error was rated as "good" in all variables. A difference was found between day 1 and 2 in V0 for three- and five-load calculations and for 50 m front crawl time (p < 0.05). No difference was found between the load-velocity profile outcomes variables compared between the three- and five-trial protocols on neither day 1 nor 2. The Bland-Altman plots showed a small bias across all resistance conditions for five loads, L0: 0.04 kg, rL0: 0.13%, V0: -0.03 m/s, and Slv: 0.003 -m/s/kg and for three loads, L0: -0.24 kg, rL0: -0.27%, V0: -0.04 m/s, Slv: 0.002 -m/s/kg. In conclusion, the load-velocity profile for front crawl swimming can be calculated with high reliability from both five and three external loads and comparable results in outcome variables were established. These methods can be used to monitor performance parameters over time, and to investigate and compare swimmers' velocity and strength capabilities to allow for individualized training prescription to improve performance.
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Affiliation(s)
- Bjørn Harald Olstad
- Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway
| | - Tomohiro Gonjo
- Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway
| | - Nikolai Njøs
- Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway
| | - Kathrin Abächerli
- Department of Health Professions, Bern University of Applied Sciences, Bern, Switzerland
| | - Ola Eriksrud
- Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway
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Cuenca-Fernández F, Batalha NM, Ruiz-Navarro JJ, Morales-Ortiz E, López-Contreras G, Arellano R. Post high intensity pull-over semi-tethered swimming potentiation in national competitive swimmers. J Sports Med Phys Fitness 2020; 60:1526-1535. [PMID: 32608939 DOI: 10.23736/s0022-4707.20.11136-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND The swimming community has shown considerable interest in using dry-land warm-ups as a method of impacting performance. This study compared the effects of high-resistance pull-over and swimming warm-up in semi-tethered resisted swimming. METHODS An incremental-load semi-tethered swimming test was individually administered in 20 national-competitive swimmers to determine the load maximizing swimming power. In different sessions, participants tested such a load 6 min after a swimming warm-up (SWU) or a dry-land warm-up (DLWU: 3 pull-over reps at 85% of the one-repetition maximum). Kinetic variables (velocity, force, acceleration, impulse, power rate of force development [RFD] and intra-cycle variation), were obtained with a linear encoder through trapezoidal integration regarding time. Kinematic variables (distance, time, stroke-rate and stroke-length), were obtained by video recordings. The differences between protocols were observed by paired-samples t-test (ANOVA). Pearson's coefficient explored correlations between kinetics and kinematics variables; significance was set at P<0.05. RESULTS DLWU increased RFD (34.52±16.55 vs. 31.29±13.70 N/s; Δ=9.35%) and stroke-rate (64.70±9.84 vs. 61.56±7.07 Hz; Δ=5.10%) compared to SWU, but decreased velocity, force, acceleration, impulse and power. During the incremental-load test velocity and power were higher than obtained after SWU (1.21±0.14 vs. 1.17±0.12 m/s; Δ=3.06%), (51.38±14.93 vs. 49.98±15.40 W; Δ=2.72%), suggesting enhancements prompted by the test itself. Correlations between stroke-length with impulse (r=0.76) and power (r=0.75) associated kinetics with kinematics. CONCLUSIONS Potentiation responses were present after the dry-land warm-up. However, swimmers may benefit more from submaximal prolonged conditioning activities such as resisted swimming rather than high-resistance dry-land sets to obtain performance enhancements.
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Affiliation(s)
- Francisco Cuenca-Fernández
- Aquatics Lab, Department of Physical Education and Sports, Faculty of Sport Sciences, University of Granada, Granada, Spain -
| | - Nuno M Batalha
- Department of Sports and Health, University of Evora, Evora, Portugal.,CHRC-UE - Comprehensive Health Research Care, University of Evora, Evora, Portugal
| | - Jesús J Ruiz-Navarro
- Aquatics Lab, Department of Physical Education and Sports, Faculty of Sport Sciences, University of Granada, Granada, Spain
| | - Esther Morales-Ortiz
- Aquatics Lab, Department of Physical Education and Sports, Faculty of Sport Sciences, University of Granada, Granada, Spain
| | - Gracia López-Contreras
- Aquatics Lab, Department of Physical Education and Sports, Faculty of Sport Sciences, University of Granada, Granada, Spain
| | - Raúl Arellano
- Aquatics Lab, Department of Physical Education and Sports, Faculty of Sport Sciences, University of Granada, Granada, Spain
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Arakawa H, Kumagawa D, Fujisaki I, Ozawa Y, Ishige Y. Development of the Rope-Climbing Ergometer for Physical Training and Testing. Sports Med Int Open 2017; 1:E128-E134. [PMID: 30539097 PMCID: PMC6226072 DOI: 10.1055/s-0043-112335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Revised: 05/12/2017] [Accepted: 05/16/2017] [Indexed: 11/11/2022] Open
Abstract
The purpose of this study was to develop and characterize a rope-climbing ergometer. A custom-made loading device that has an eddy current brake with an electrical current control circuit was developed to impose resistive load on the rope. A calibration test was first performed using a three-phase induction motor to associate the scale of the load-level setting (100 levels) with the resultant traction force. The calibration test yielded criteria values of loads (123 N at Level 0 and 1064 N at Level 100). The human test was carried out by 14 male subjects. The participants performed eight sets of 10-second maximal-effort exercises at different levels. Presumable trajectories of force, velocity, and power were obtained. The mean force increased by 161% (from 147.5 N at Level 0 to 383.7 N at Level 18), whereas the mean velocity decreased by 64.7% (from 1.87 m/s at Level 0 to 0.66 m/s at Level 18). The mean power reached its peak at Level 9 (320 W). The new rope ergometer for physical training and testing was successfully developed and characterized in this study. However, it remains to be seen whether its concurrent validity and reliability are qualifiable.
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Affiliation(s)
- Hiroshi Arakawa
- Physical Education, International Budo University, Katsuura, Chiba, Japan
| | - Daisuke Kumagawa
- Department of Physical Education, Kokushikan University, Tama, Tokyo, Japan
| | - Iwao Fujisaki
- Research and Development, Apowatec Corporation, Yashio, Saitama, Japan
| | - Yoshiaki Ozawa
- Research and Development, Apowatec Corporation, Yashio, Saitama, Japan
| | - Yusuke Ishige
- Department of Sports Sciences, Japan Institute of Sports Sciences, Kita, Tokyo, Japan
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Gatta G, Cortesi M, Zamparo P. The Relationship between Power Generated by Thrust and Power to Overcome Drag in Elite Short Distance Swimmers. PLoS One 2016; 11:e0162387. [PMID: 27654992 PMCID: PMC5031421 DOI: 10.1371/journal.pone.0162387] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Accepted: 08/22/2016] [Indexed: 11/19/2022] Open
Abstract
At constant average speed (v), a balance between thrust force (Ft) and drag force (Fd) should occur: Ft−Fd = 0; hence the power generated by thrust forces (Pt = Ft·v) should be equal to the power needed to overcome drag forces at that speed (Pd = Fd·v); the aim of this study was to measure Pt (tethered swims), to estimate Pd in active conditions (at sprint speed) and to compare these values. 10 front crawl male elite swimmers (expertise: 93.1 ± 2.4% of 50 m world record) participated to the study; their sprint speed was measured during a 30 m maximal trial. Ft was assessed during a 15 s tethered effort; passive towing measurement were performed to determine speed specific drag in passive conditions (kP = passive drag force/v2); drag force in active conditions (Fd = kA·v2) was calculated assuming that kA = 1.5·kP. Average sprint speed was 2.20 ± 0.07 m·s-1; kA, at this speed, was 37.2 ± 2.7 N·s2·m-2. No significant differences (paired t-test: p > 0.8) were observed between Pt (399 ± 56 W) and Pd (400 ± 57 W) and a strong correlation (R = 0.95, p < 0.001) was observed between these two parameters. The Bland-Altman plot indicated a good agreement and a small, acceptable, error (bias: -0.89 W, limits of agreement: -25.5 and 23.7 W). Power thrust experiments can thus be suggested as a valid tool for estimating a swimmer’s power propulsion.
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Affiliation(s)
- Giorgio Gatta
- Department for Life Quality Studies, Rimini, School of Pharmacy, Biotechnology and Sport Science, University of Bologna, Bologna, Italy
- * E-mail:
| | - Matteo Cortesi
- Department for Life Quality Studies, Rimini, School of Pharmacy, Biotechnology and Sport Science, University of Bologna, Bologna, Italy
| | - Paola Zamparo
- Department of Neurological, Biomedical and Movement Sciences, University of Verona, Verona, Italy
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Ribeiro J, Figueiredo P, Morais S, Alves F, Toussaint H, Vilas-Boas JP, Fernandes RJ. Biomechanics, energetics and coordination during extreme swimming intensity: effect of performance level. J Sports Sci 2016; 35:1614-1621. [PMID: 27602781 DOI: 10.1080/02640414.2016.1227079] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The present study aimed to examine how high- and low-speed swimmers organise biomechanical, energetic and coordinative factors throughout extreme intensity swim. Sixteen swimmers (eight high- and eight low-speed) performed, in free condition, 100-m front crawl at maximal intensity and 25, 50 and 75-m bouts (at same pace as the previous 100-m), and 100-m maximal front crawl on the measuring active drag system (MAD-system). A 3D dual-media optoelectronic system was used to assess speed, stroke frequency, stroke length, propelling efficiency and index of coordination (IdC), with power assessed by MAD-system and energy cost by quantifying oxygen consumption plus blood lactate. Both groups presented a similar profile in speed, power output, stroke frequency, stroke length, propelling efficiency and energy cost along the effort, while a distinct coordination profile was observed (F(3, 42) = 3.59, P = 0.04). Speed, power, stroke frequency and propelling efficiency (not significant, only a tendency) were higher in high-speed swimmers, while stroke length and energy cost were similar between groups. Performing at extreme intensity led better level swimmers to achieve superior speed due to higher power and propelling efficiency, with consequent ability to swim at higher stroke frequencies. This imposes specific constraints, resulting in a distinct IdC magnitude and profile between groups.
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Affiliation(s)
- João Ribeiro
- a Centre of Research, Education, Innovation and Intervention in Sport, Faculty of Sport , University of Porto , Porto , Portugal.,b Porto Biomechanics Laboratory , University of Porto , Porto , Portugal
| | - Pedro Figueiredo
- c School of Physical Education , Federal University of Rio Grande do Sul , Porto Alegre , Brazil.,d Department of Kinesiology , University of Maryland , College Park , MD , USA
| | - Sara Morais
- b Porto Biomechanics Laboratory , University of Porto , Porto , Portugal
| | - Francisco Alves
- e Faculty of Human Movement Technical , University of Lisbon , Lisbon , Portugal
| | - Huub Toussaint
- f School of Sports and Nutrition , Amsterdam University of Applied Sciences , Amsterdam , Netherlands
| | - João Paulo Vilas-Boas
- a Centre of Research, Education, Innovation and Intervention in Sport, Faculty of Sport , University of Porto , Porto , Portugal.,b Porto Biomechanics Laboratory , University of Porto , Porto , Portugal
| | - Ricardo Jorge Fernandes
- a Centre of Research, Education, Innovation and Intervention in Sport, Faculty of Sport , University of Porto , Porto , Portugal.,b Porto Biomechanics Laboratory , University of Porto , Porto , Portugal
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Abstract
The aim of this study was to analyse to what extent the use of different loads modifies freestyle stroke and coordination parameters during semi-tethered swimming, and to examine whether those changes are positive or negative to swimming performance. First, behaviour of swimming speed (v), stroke rate (SR) and stroke length (SL) with increasing loads was examined. Secondly, mean and peak speed of propulsive phases (propvmean and propvpeak) were analysed, as well as the relative difference between them (%v). Finally, index of coordination (IdC) was assessed. Eighteen male swimmers (22.10±4.31years, 1.79±0.07m, 76.74±9.00kg) performed 12.5m maximal sprints, pulling a different load each trial (0, 1.59, 2.21, 2.84, 3.46, 4.09, 4.71, 5.34, 5.96, 6.59, 7.21 and 7.84kg). Rest between repetitions was five minutes. Their feet were tied together, keeping a pull-buoy between legs and isolating the upper limb action. A speedometer was used to measure intra-cycle speed and the test was recorded by a frontal and a lateral underwater cameras. Variables v and SL decreased significantly when load increased, while SR remained constant (p<0.05). Propvmean and propvpeak decreased significantly with increasing loads (p<0.05). In contrast, %v grew when load rose (r = 0.922, p<0.01), being significantly different from free swimming above 4.71kg. For higher loads, swimmers did not manage to keep a constant velocity during a complete trial. IdC was found to increase with loads, significantly from 2.84kg (p<0.05). It was concluded that semi-tethered swimming is one training method useful to enhance swimmers’ performance, but load needs to be individually determined and carefully controlled.
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Fujita T, Iwata M, Fukuda M. Reliability and Validity of a New Test for Muscle Power Evaluation of Stroke Patients. J Phys Ther Sci 2011. [DOI: 10.1589/jpts.23.259] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Affiliation(s)
- Toshifumi Fujita
- Department of Disability and Health, Division of Health Sciences, Hirosaki University Graduate School of Health Sciences
| | - Manabu Iwata
- Department of Disability and Health, Division of Health Sciences, Hirosaki University Graduate School of Health Sciences
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Laterality of Hand Grip and Elbow Flexion Power in Right Hand–Dominant Individuals. Int J Sports Physiol Perform 2009; 4:355-66. [DOI: 10.1123/ijspp.4.3.355] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Purpose:This study aimed to compare the laterality, and its gender difference, of hand grip and elbow flexion power according to load in right hand–dominant individuals.Results:The subjects were 15 healthy young males (age 22.1 ± 0.7 y, height 171.3 ± 3.4 cm, mass 64.5 ± 4.1 kg) and 15 healthy young females (age 22.4 ± 1.0 y, height 161.1 ± 3.0 cm, mass 55.4 ± 4.6 kg). Isotonic peak power was measured with 6 different loads ranging from 20% to 70% of maximum voluntary contraction (MVC) for grip and elbow flexion movements.Results:The peak power was significantly larger in males than in females in both movements (ratio, males:females was 58.1:49.4%). The dominant right hand had larger peak power in all loads for hand grip power (ratio, dominant:nondominant was 83.6:71.1%) and in loads of 20% to 50% MVC for elbow flexion power (88.7:85.7%) in both genders, confirming laterality in both movements. The peak power ratio of the dominant right hand to the nondomi-nant left hand was significantly larger in hand grip than in elbow flexion for all loads in females.Conclusion:Even though laterality was confirmed in both grip and elbow flexion, gender difference is more marked in hand grip.
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