Despite the short duration of the event, the aerobic energy contribution covers about 50 % of total metabolic energy liberation, highlighting that both aerobic and anaerobic energy processes should be developed to improve the 100 m swimming performance. Lower limbs action provided an important contribution in the energy availability in working muscles being advised its full use in this short duration and very high-intensity event.

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The purpose of this study was to examine the oxygen uptake () kinetics and the energy systems’ contribution at 97.5, 100 and 102.5% of the maximal lactate steady state (MLSS) swimming intensity. Ten elite female swimmers performed three-to-five 30 min submaximal constant swimming bouts at imposed paces for the determination of the swimming velocity (v) at 100%MLSS based on a 7 x 200 m intermittent incremental protocol until voluntary exhaustion to find the v associated at the individual anaerobic threshold. kinetics (cardiodynamic, primary and slow component phases) and the aerobic and anaerobic energy contributions were assessed during the continuous exercises, which the former was studied for the beginning and second phase of exercise. Subjects showed similar time delay (TD) (mean = 11.5–14.3 s) and time constant (τp) (mean = 13.8–16.3 s) as a function of v, but reduced amplitude of the primary component for 97.5% (35.7 ± 7.3 mL.kg.min-1) compared to 100 and 102.5%MLSS (41.0 ± 7.0 and 41.3 ± 5.4 mL.kg.min-1, respectively), and τp decreased (mean = 9.6–10.8 s) during the second phase of exercise. Despite the slow component did not occur for all swimmers at all swim intensities, when observed it tended to increase as a function of v. Moreover, the total energy contribution was almost exclusively aerobic (98–99%) at 97.5, 100 and 102.5%MLSS. We suggest that well-trained endurance swimmers with a fast TD and τp values may be able to adjust faster the physiological requirements to minimize the amplitude of the slow component appearance, parameter associated with the fatigue delay and increase in exhaustion time during performance, however, these fast adjustments were not able to control the progressive fatigue occurred slightly above MLSS, and most of swimmers reached exhaustion before 30min swam.

Our purpose was to examine the swimming biophysical responses at velocities (v) of 97.5, 100 and 102.5% of the maximal lactate steady state (MLSS). Ten elite female swimmers performed three-to-five 30-min constant tests at imposed paces to determine 97.5, 100 and 102.5%MLSS v. Gas exchange, blood lactate concentration ([La-]), stroke rate (SR) and v were determined during each test. The v values at 97.5, 100 and 102.5%MLSS were 1.21±0.07, 1.24±0.07 and 1.27±0.07m.s(-1), respectively. Oxygen uptake (V̇O2) and Pulmonary ventilation (V̇E) increased as function of v. SR and stroke length (v/SR=SL) increased as a function of v. All measured variables were constant as a function of time at 97.5%MLSS and 100%MLSS. At 102.5%MLSS SR increased (3.5%) and stroke length (SL) decreased (3.5%) as a function of time. While V̇O2 was constant at 102.5%MLSS, [La-] and V̇E increased as a function of time, suggesting hyperventilation, at v's of 97.5%MLSS and 100%MLSS swimmers completed the 30min swim in spite of decreased SL and increased SR. However, the decrease in SL and increased SF were accompanied by increased [La-] and V̇E and resulted in the inability of most swimmers to complete the 30min swim presumably due to fatigue at 102.5%MLSS.

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BackgroundFructose-based diets are apparently related to the occurrence of several metabolic dysfunctions, but the effects of the consumption of high amounts of fructose on body tissues have not been well described. The aim of this study was to analyze the general characteristics and the lipid content of different tissues of rats after chronic ingestion of a fructose rich soft drink.MethodsForty-five Wistar rats were used. The rats were divided into three groups (n = 15) and allowed to consume water (C), light Coca Cola ® (L) or regular Coca Cola® (R) as the sole source of liquids for eight weeks.ResultsThe R group presented significantly higher daily liquid intake and significantly lower food intake than the C and L groups. Moreover, relative to the C and L groups, the R group showed higher triglyceride concentrations in the serum and liver. However, the L group animals presented lower values of serum triglycerides and cholesterol than controls.ConclusionsBased on the results, it can be concluded that daily ingestion of a large amount of fructose- rich soft drink resulted in unfavorable alterations to the lipid profile of the rats.

Dalamitros, A.A., Manou, V., & Pelarigo, J.G. (2014). Laboratory-based tests for swimmers: methodology, reliability, considerations and relationship with front-crawl performance. J. Hum. Sport Exerc., 9(1), pp.172-187. Monitoring training process in swimming is essential for providing valuable information for both coaches and athletes. Among a large variety of laboratory-based tests used for the quantification of swimmers abilities and evaluation of fitness status, the most representative and easy to apply ones are chosen to be presented in this review. Furthermore, these tests reliability, methodology, referred considerations and relationship with front-crawl swimming performance are reported. Based on the previous mentioned criteria, the assessment of aerobic, anaerobic power and muscular strength, are analyzed. From the data examined, it is concluded that despite their reliability and efficacy in determining adaptations after a training period, as well as, detecting differences between athletes' training status, laboratory-based tests assessing aerobic, anaerobic power and muscular strength for swimmers does not meet the criterion of specificity and disregard the crucial role of technique.