Catalogue Search | MBRL
Are you sure you want to remove the book from the shelf?
{{itemTitle}}
78
result(s) for
"Swim time"
Sort by:
Swimming into trouble
\"As a member of the Vipers Swim Team, Julia Nam's always in the pool. Mountainview Community Center is like her second home, not only because swimming at the aquatic center is her favorite thing in the world, but also because her parents run the center's sushi café. She's the youngest swimmer on the team, but definitely not the slowest. Julia can't wait for Personal Best Day -- the most important day for all of the swimmers. If their times are good enough, they can enter a big regional swim meet. But then the worst thing happens. A sharp pain in Julia's ear reveals an infection and she's forbidden to swim for ten days. How can she get timed during Personal Best Day when she's not allowed in the water? Julia is desperate to get back in the pool, even if it means having to go behind her parents' backs in order to do so. But Julia's solution lands her in a sticky situation, and it's going to require the entire community center to come together to help her out of it!\"-- Provided by publisher.
CHILDBOOK
Effects of carbohydrate intake and body composition on short-distance swimming performance in adolescents
Background This study aimed to evaluate the influence of carbohydrate intake and body composition on athletic performance in adolescent swimmersMethods A cross-sectional study was conducted with 22 adolescent swimmers (both sexes) from a sports center in Paraíba, Brazil. Pre- and post-training carbohydrate intake was assessed using 24-hour dietary recalls and compared against the International Society of Sports Nutrition (ISSN) guidelines. Body composition was estimated via skinfold measurements, using age- and sex-specific cutoff points. Swimming performance was assessed based on the time to complete a 25-meter front crawl. Performance was categorized as optimal ( < 15 s), good (15–16 s), or regular ( > 16 s). These thresholds were defined by the authors based on the distribution of swim times in the study sample. Statistical analysis was performed using IBM® SPSS® Statistics 20.0. Associations between categorical variables were tested using the Chi-square test, with significance set at p < 0.05.Results Although 60% of participants with a “good” body fat percentage demonstrated better performance, no statistically significant association was observed between body composition and swim time (p = 0.073). In contrast, participants who consumed carbohydrates in amounts exceeding ISSN recommendations before training showed significantly better performance (p = 0.003). Additionally, all participants whose pre-training carbohydrate intake was below the recommended levels demonstrated regular performance (p = 0.003).Conclusions While body fat percentage is a relevant marker of body composition, this study suggests that adequate pre-training carbohydrate intake may have a greater impact on swimming performance. These findings reinforce the importance of carbohydrate availability as a key nutritional strategy, particularly in sports requiring both immediate and sustained energy, such as swimming.
Journal Article
Effect of Plyometric Training on Swimming Block Start Performance in Adolescents
Bishop, DC, Smith, RJ, Smith, MF, and Rigby, HE. Effect of plyometric training on swimming block start performance in adolescents. J Strength Cond Res 23(7)2137-2143, 2009-This study aimed to identify the effect of plyometric training (PT), when added to habitual training (HT) regimes, on swim start performance. After the completion of a baseline competitive swim start, 22 adolescent swimmers were randomly assigned to either a PT (n = 11, age13.1 ± 1.4 yr, mass50.6 ± 12.3 kg, stature162.9 ± 11.9 cm) or an HT group (n = 11, age12.6 ± 1.9 yr, mass43.3 ± 11.6 kg, stature157.6 ± 11.9 cm). Over an 8-week preseason period, the HT group continued with their normal training program, whereas the PT group added 2 additional 1-hour plyometric-specific sessions, incorporating prescribed exercises relating to the swimming block start (SBS). After completion of the training intervention, post-training swim start performance was reassessed. For both baseline and post-trials, swim performance was recorded using videography (50Hz Canon MVX460) in the sagital plane of motion. Through the use of Silicon Coach Pro analysis package, data revealed significantly greater change between baseline and post-trials for PT when compared with the HT group for swim performance time to 5.5 m (−0.59 s vs. −0.21 s; p < 0.01) and velocity of take-off to contact (0.19 ms vs. −0.07 ms; p < 0.01). Considering the practical importance of a successful swim start to overall performance outcome, the current study has found that inclusion of suitable and safely implemented PT to adolescent performers, in addition to HT routines, can have a positive impact on swim start performance.
Journal Article
Effect of swimming intensity on subsequent cycling and overall triathlon performance
Objectives: To investigate the effects of different swimming intensities on subsequent cycling and overall triathlon performance. Methods: Nine highly trained, male triathletes completed five separate laboratory sessions comprising one graded exercise test, a swim time trial (STT), and three sprint distance triathlons (TRI). The swimming velocities of the three TRI sessions were 80–85% (S80), 90–95% (S90), and 98–102% (S100) of the STT velocity. Subsequent cycling and running were performed at a perceived maximal intensity. Swimming stroke mechanics were measured during the swim. Plasma lactate concentration and ratings of perceived exertion were recorded at the conclusion of the swim and over the course of subsequent cycling and running. Oxygen consumption was recorded during the cycle. Results: The S80 and S90 cycle times were faster than the S100 cycle time (p<0.05). The overall triathlon time of S80 was faster than that of S100 (p<0.05). The S100 swim was characterised by a greater stroke rate than S80 and S90 (p<0.05) and a greater plasma lactate concentration than S80 (p<0.01). Conclusion: A swimming intensity below that of a time trial effort significantly improves subsequent cycling and overall triathlon performance.
Journal Article
Impact of antioxidant potential of rohu (Labeo rohita) swim bladder gelatin hydrolysate on oxidative stability, textural and sensory properties of fish sausage enriched with polyunsaturated fatty acids
The impact of rohu swim bladder gelatin hydrolysate (SBGH) at different levels on textural, sensory, oxidative, and microbial properties of polyunsaturated fatty acids enriched rohu fish cooked sausages (PUFA-RFS) were investigated in the current study. SBGH addition enhanced the lightness values of PUFA-RFS compared to both control sausages (without SBGH and with butylated hydroxyanisole (BHA) (P > 0.05). PUFA-RFS added with 3% SBGH exhibited higher hardness, cohesiveness, and gumminess throughout the storage duration at both 4 °C and −20 °C temperatures when compared to other sausages counterparts. PUFA-RFS added with SBGH displayed lower PV, TBARS, and total microbial counts than the control sausages. Furthermore, PV, TBARS, and total microbial count values of sausage decreased with an increase in SBGH level, indicating retardation in lipid oxidation and microbial growth by SBGH in a dose-depended manner. Nevertheless, sausage added with 3% SBGH had higher overall acceptability than other sausage counterparts. Therefore, SBGH could retard lipid oxidation and improves textural properties of PUFA-enriched fish sausage.
Journal Article
Sex Determination of X and Y Separated Fresh Bull Sperm Using SRY Gene Copy Number Analysis
Background and Objective The present study employed absolute quantitative PCR to determine the sex of sperm fractions after subjecting fresh bull semen to motility‐based separation using resiquimod, an agonist of Toll‐like receptors 7 and 8, which is supposed to selectively impair the motility of sperm carrying the X chromosome. Methods The upper and lower fractions obtained from fresh bull sperm following the swim‐up procedure, in both the control (untreated) and resiquimod‐treated groups, were subjected to sperm DNA extraction and absolute quantification by real‐time PCR to determine the number of Y chromosome‐bearing sperm. Ten different dilutions were prepared from the cloned plasmid with SRY sequence. Isolated sperms from the upper and lower layers in the resiquimod‐treated group and the fresh non‐treated sperm were also used for in vitro embryo production. Results The SRY gene copy number was significantly higher in the upper than the lower layer in the resiquimod‐treated group (p < 0.05). The sex of the embryos produced with sperm harvested from the upper and lower layers of the treatment group confirmed the results of the PCR, because the number of male embryos produced from the upper layer sperm was significantly higher than the lower layer (73.33% vs. 28.57%) (p < 0.05). Conclusion Considering that this sexing method is low‐cost and can be done with little facilities, it can be used in the future for the isolation of X and Y sperms in bulls. Resiquimod treatment and swim‐up significantly enriched Y‐bearing bull sperm in the separated fraction, confirmed by higher SRY copy numbers and increased male embryo production.
Journal Article
DMSO induces major morphological and physiological alterations in zebrafish embryos
Dimethyl sulfoxide (DMSO) is a polar aprotic solvent that dissolves both polar and nonpolar compounds and is miscible in a wide range of organic solvents as well as water. These characteristics render DMSO one of the most widely used solvents in pharmaceutical industry, as well in basic biomedical research, such as in developmental biology studies. The analysis of the effects of DMSO during the development of zebrafish larvae is particularly important since zebrafish is one of the most studied vertebrate models in developmental biology and in toxicology. It has been reported that DMSO at concentrations up to 1% are safe to be used in zebrafish embryo developmental toxicity assays, but fundamental questions such as whether and how different concentrations of DMSO affect the morphology and physiology of zebrafish have not been investigated. Therefore, our study focused on the analysis of DMSO treatment during zebrafish development using high resolution optical microscopy and real-time video-microscopy of the whole embryo, as well as focusing on some organs and tissues. Our results show that concentrations above 5% of DMSO are lethal to embryos, whereas concentrations between 1–4% induce different morphological and physiological alterations in embryos. The alterations observed include up-curved tail, heart beating frequency, heart edema, somite size, myofibril alignment, melanocyte size, notochord and swim bladder morphology. These results show for the first time a detailed analysis of the major effects of the widely used solvent DMSO during zebrafish development and call for attention in the use of DMSO in basic and applied research.
Journal Article
Lipopolysaccharide-induced depressive-like behavior is mediated by indoleamine 2,3-dioxygenase activation in mice
Although elevated activity of the tryptophan-degrading enzyme indoleamine 2,3-dioxygenase (IDO) has been proposed to mediate comorbid depression in inflammatory disorders, its causative role has never been tested. We report that peripheral administration of lipopolysaccharide (LPS) activates IDO and culminates in a distinct depressive-like behavioral syndrome, measured by increased duration of immobility in both the forced-swim and tail suspension tests. Blockade of IDO activation either indirectly with the anti-inflammatory tetracycline derivative minocycline, that attenuates LPS-induced expression of proinflammatory cytokines, or directly with the IDO antagonist 1-methyltryptophan (1-MT), prevents development of depressive-like behavior. Both minocycline and 1-MT normalize the kynurenine/tryptophan ratio in the plasma and brain of LPS-treated mice without changing the LPS-induced increase in turnover of brain serotonin. Administration of
L
-kynurenine, a metabolite of tryptophan that is generated by IDO, to naive mice dose dependently induces depressive-like behavior. These results implicate IDO as a critical molecular mediator of inflammation-induced depressive-like behavior, probably through the catabolism of tryptophan along the kynurenine pathway.
Journal Article
Halochromic optical nose for assessment of spoilage of packed seer fish (II): leaching resistance, correlation between halochromism and volatile amines
Purpose
Development of thin film sensors with pH function for noninvasive real-time monitoring of spoilage of packed seafood such as fish, crab and shrimp are described in this study. It is also the purpose of this study to enhance the leaching resistance of the sensors by using a suitable strategy and to quantitatively correlate the sensor’s halochromism with the total volatile amine.
Design/methodology/approach
To prepare halochromic sensors with better leaching resistance, biocompatible materials such as starch, agar, polyvinyl alcohol and cellulose acetate along with a halochromic dye were used to prepare the thin film sensors. These thin films were evaluated for monitoring the spoilage of packed seafood at room temperature, 4°C and −2°C up to 30 days. The halochromic sensors were characterized using UV-visible and FT-IR spectroscopy.
Findings
CIELab analyses of the halochromism of the thin film sensors revealed that the color changes exhibited by the sensors in response to the spoilage of seafood are visually distinguishable. Further, the halochromic response of the thin films was directly proportional to the amount of total volatile base nitrogen that evolved from the packed seafood. Excellent leaching resistance was observed for the developed thin film sensors. The halochromic property of the sensors is reversible and thus the sensors are recyclable. Besides, the thin film sensors exhibited significant biodegradability.
Originality/value
This study provides insights for use of different biocompatible polymers for obtaining enhanced leaching resistance in halochromic sensors. Further, the color changes exhibited by the sensors are in line with the total volatile amines evolved from the packed seafood. These results highlight the importance of the developed halochromic thin film sensors for real-time monitoring of the spoilage of packed seafood.
Journal Article
Swimming Performance in Large Yellow Croaker: Effects of Group Size, Test Protocol, and Recovery Time On Critical Swimming Speed
Swimming is critical for fish survival, and little attention has been paid to the swimming performance of large yellow croaker, the largest farmed marine fish in China. To address this gap, we conducted a study to measure the critical swimming speed (Ucrit) of 1050 croaker in a designed swim test flume. Our findings shed light on the effects of group size, Ucrit test protocol, and recovery time on swimming performance. The water flow in the swim flume increased steadily and linearly. The linear fit equation was y = 2.89x + 1.79 with an R2 of 0.99. With the help of the swim flume, we found that group size, and the Ucrit test protocol had a significant effect on the Ucrit values, except for the recovery time: The Ucrit values obtained in the ramp-Ucrit test averaged 28.32 ± 6.11 cm.s−1, which was significantly lower than that obtained in the traditional Ucrit test of 32.75 ± 7.60 cm.s−1; The Ucrit value of a group size of 50 fish was 33.51 ± 5.96 cm.s−1, which was significantly higher than that of a group of 200 fish (28.49 ± 6.37 cm.s−1). These results provide insights into the swimming performance of large yellow croaker and can be used to standardize the swimming test protocols.
Journal Article