Adult Swimmers Research Articles

Nutritional Knowledge and Beliefs between Fitness Room Users and Swimmers

LANGUAGE NOTE | Document text in English; abstract also in Chinese.The main purposes of the present study were to investigate the situation of nutritional knowledge and beliefs of 73 adults fitness room users (FRU) and 58 adult swimmers (SWR) and the ranged in age from 18 〜 65 years. Subjects selected from 5 different health clubs and swimming pools. It included community, commercial or corporate center and located at Hong Kong Island or Kowloon. A total 131 of adults completed the questionnaires, which included (a) background information, (b) multiple choice nutrition knowledge questions and (c) true-or-false nutrition belief statements. 2X2 ANOVA and Pearson correlation were utilized to analyze the different in between the nutritional knowledge and beliefs in exercise groups and gender. Results show that the FRU and SWR scores of nutritional knowledge and beliefs were low and no significant differences were found between exercise groups and gender. Only significant difference in relationship in nutrition knowledge and belief on swimmer group was observed.此研究目的是探討成人健身室使用者(N=73)及游泳人仕(N=58)們對營養知識及飲食信念的情況。從五間不同的健體會所及游泳池中邀請受訪者完成一份問卷調查。受訪對象的年齡介乎18至65歲。此五間會所位於香港及九龍等地，會所形式包括：社區，私人及公司所屬之會所等。共131人完成此問卷調查，而問卷分為三部份；甲部：個人資料，乙部：營養知識及丙部：飲食信念。營養知識以多項選擇的提問方式，而飲食信念以是與否作判斷問題的真確性。用2x2ANOVA 及Pearson的相關系數分析兩運動組別及性別對營養知識及飲食信念之差別。結果指出健身室使用者及游泳人仕們對營養知識及飲食信念的分數也低。唯游泳人仕對營養知及飲食信念有相互關係。

EVALUATION OF THE HEALTH RISK ASSOCIATED WITH EXPOSURE TO CHLOROFORM IN INDOOR SWIMMING POOLS

The exposure of swimmers to chloroform (CHCl5) was investigated in indoor swimming pools of the Quebec City region along with the associated carcinogenic risk. Six training sessions involving 52 competition swimmers (11 to 20 yr old) were conducted in 3 different pools, while 12 adult leisure swimmers attended 5 sessions, each held in a different pool. For each session, water and ambient air CHCl3 concentrations were measured and CHCl3 levels in alveolar air samples (CHCl3ALV) collected from swimmers prior to entering the swimming pool premises and after 15, 35, and 60 min of swimming. Mean water concentrations varied from 18 µg/L to 80 µg/L, while those in air ranged from 78 µg/m3 to 329 µg/m3. Multiple linear regression analyses revealed that CHCl3ALV values in competition swimmers were strongly correlated to ambient air and water levels, and to a lesser degree to the intensity of training. Only ambient air concentration was positively correlated to CHCl3ALV in the leisure group. Concentrations of CHCl3 metabo lites bound to hepatic and renal macromolecules, estimated using a physiologically based pharmacokinetic (PBPK) model, were 1.6 and 1.9 times higher for the competition swimmers than for the leisure swimmers, respectively. The highest hepatic concentration predicted in competition swimmers, 0.22 µg CHCl equivalents/kg of tissue, was at least 10,000 times lower than the smallest no observed3effect level for liver tumors in animals. Data indicate that the safety margin is therefore very large, for competitive swimmers as well as for leisure swimmers.

Lifeguards' vigilance: effects of child-adult ratio and lifeguard positioning on scanning by lifeguards.

Observers recorded visual scanning by four lifeguards at three indoor public swimming pools. Scanning increased as a positive function of the ratio of children to adult swimmers, i.e., scanning was greater when the ratio was high, suggesting that lifeguards became more concerned about the risks to children and the ability of nearby adult swimmers to monitor these children when the number of children significantly exceeded the number of adults. Absolute numbers of children, however, decreased number of scans, possibly because of greater number of incidents and rule violations requiring lifeguards' attention which competed with watching the pool. Lifeguards were more likely to scan a pool area when they were in elevated towers versus standing on the pool decks. Lifeguards' scanning declined later in the day, possibly due to fatigue or because of competing activities of pool maintenance.

Physiological Determinants of Sprint Swimming Performance in Children and Young Adults

The purpose of this study was to identify physiological determinants of sprint (91.4 m) swimming velocity that discriminated between performance levels in male children (n = 12, age = 10.26 ± 1.00) and in young adult (n = 16, age = 19.78 ± 1.61) competitors. Independent variables included stature, arm length, body mass, body density, body fat, muscularity, leg power, and measures taken during swimming, which included arm stroke force, leg kick force, peak oxygen consumption rate, stroke rate, and stroke efficiency. Discriminant analysis revealed that in the children, higher levels of leg-kick force, peak VO2, stroke efficiency, and muscularity were the most potent variables contributing to the classification of the faster swimmers. In the young adults, higher levels of stroke efficiency, body density, and muscularity, served as the significant discriminators of the faster swimmers. When compared across age groups, these results indicated that substantial differences in stroke efficiency and muscularity significantly accounted for higher performance in these children versus young adult sprint swimmers.

Peak Heart Rates during Maximal Running and Swimming: Implications for Exercise Prescription

Thirty-four college-age fitness swimmers, 19 males and 15 females, were maximally tested during treadmill running (TR) and tethered swimming (TS). A discontinuous, graded test protocol was used for both TR and TS with 2-min stages and 1-min rest periods. Peak HRs were obtained via a UNIQ CIC monitor during the last 120 s of each stage. Blood lactate was measured at 3 min post exercise using a YSI Model 27 Analyzer. TS peak HR was significantly lower (p less than 0.05) than both the age-predicted HRmax (220-age) and TR peak HR by 13 and 11 bt.min-1, respectively. Blood lactate for TS (8.0 mmol.l-1) and TR (8.1 mmol.l-1) were similar. Mean target heart rate range (THRR) calculated from TS peak HR (144-176 bt.min-1) was significantly lower than THRR calculated from age-predicted max HR (151-187 bt.min-1) and TR peak HR (151-186 bt.min-1). For young adult fitness swimmers, we suggest reducing the HRmax obtained from treadmill exercise or predicted from age by 12 bt.min-1. This correction appears to be a reasonable estimate of swimming HRmax that can be used for calculating exercise intensity.

The Effect of Growth on Drag in Young Swimmers

In this study the relationship between morphological data and active drag, as measured on the MAD system (system to measure active drag), and the effect of a 2.5-year period of growth was examined in a group of children (mean age at the start of the study, 12.9 years). During this period the children showed a mean increase in height from 1.52 to 1.69 m, and in weight from 40.0 to 54.7 kg. Also the body cross-sectional area (Ap), previously reported to relate strongly to drag in a group of adult swimmers, showed an increase in size of 16%. However, the drag did not change; the mean drag force for all subjects swimming at 1.25 m•s−1 was 30.1 N (±2.37) in 1985 and 30.8 N (±4.50) in 1988. The increase in height resulted in a decrease in the Froude Number (Fr) and hence in a decrease in wave-making resistance. Furthermore, form indices derived from ship-building technology demonstrated changes that indicated a more streamlined body form. Therefore it was concluded that during growth a complex process takes place in which different factors determining drag, such as height, body shape (Cd), and Ap, change in directions, having opposite effects on drag.

Endurance swimming, intravascular hemolysis, anemia, and iron depletion: New perspective on athlete's anemia

Swimmers were evaluated for the anemia, intravascular hemolysis, and iron deficiency reported in endurance runners. Plasma concentrations of ferritin, haptoglobin, and hemoglobin were measured in nine collegiate swimmers through the competitive season and in 23 adult swimmers before and after endurance races of 1.5 km to 10 km. About 10 percent of the swimmers had low hemoglobin concentrations. The severity of this “swimmer's anemia” correlated with the amount of swimming in both men and women. Intravascular hemolysis occurred during all the races; the fastest swimmers in the longest races had the greatest decreases in haptoglobin. About 25 percent of the swimmers had low baseline haptoglobin concentrations. Iron depletion was found in 11 percent of the men and 57 percent of the women, but their athletic performance was not notably impaired. Iron depletion, anemia, and intravascular hemolysis in athletes in a nontraumatic sport suggest that mechanisms other than footstrike are components of athlete's hemolysis.

Surface wave discrimination between prey and nonprey by the back swimmerNotonecta glauca L. (Hemiptera, Heteroptera)

1. The back swimmerNotonecta glauca discriminates between prey and nonprey (including conspecifics) by means of surface waves. Waves generated by aquatic, semiaquatic, and terrestrial insect prey of the back swimmer were recorded and analyzed. Their relative spectra were statistically compared with those of waves elicited during ‘swimming,’ ‘diving,’ ‘emerging,’ ‘turning,’ ‘grooming,’ or ‘paddling’ by adult back swimmers, with swimming waves of back-swimmer larvae I–V, and with ‘noise’ caused by the fall of inanimate objects on to the water surface. 2. Waves from almost all these sources include amplitudes above the vibration sensitivity threshold ofNotonecta. Since absolute amplitudes vary strongly within all wave types and depend on the distance between wave emitter and receiver, they cannot be used byNotonecta to discriminate between wave types. 3. It is concluded thatNotonecta discriminates wave types according to their frequency ranges. With respect to this, the investigated surface waves may be classified into three different groups: