Browsing by Author "Sousa, Ana"
Now showing 1 - 4 of 4
Results Per Page
Sort Options
- Comparison between aerobic power parameters at different time-averaging intervals in swimming: An updatePublication . Sousa, Ana; Jesus, Kelly; Figueiredo, Pedro; Sousa, MarisaSousa et al. (Open Sports Sci J, 3: 22 – 24, 2010) showed that different time averaging intervals lead to distinct VO2 values in a maximal 200m front crawl effort, evidencing higher VO2 values for breath-by-breath sampling, and differences between this latter data acquisition and all the other less frequent time intervals studied (5, 10, 15 and 20 s). These are interesting outputs in the field of exercise physiology applied to swimming once: (1) VO2 assessment is conducted in a swimming pool with a portable gas analyser which allowed breath-by-breath measurements, and not in a swimming flume with a Douglas bag technique or mixing chamber analyser, as traditionally occurs, and (2) the comparison between different time-averaging intervals used to remove breath-by-breath fluctuations during exercise periods has remained neglected, in sport in general and swimming in particular. Therefore, in the present study, we investigate the influence that different time averaging intervals have in aerobic power related parameters (VO2peak and VO2max). Ten subjects performed 200m front crawl effort at supra-maximal intensities (all-out test) and other ten subjects performed 200m front crawl effort at maximal aerobic intensities (100% of VO2max).The intensity at which the 200m front crawl was performed (supra-maximal and maximal intensities) had a significant effect on VO2peak and VO2max values obtained for each averaging intervals studied.
- High-intensity Interval Training in Different Exercise Modes: Lessons from Time to ExhaustionPublication . Sousa, Ana; Fernandes, Ricardo; Boas, Joao; Figueiredo, PedroTo provide information for high-intensity interval training (HIIT) load, we compared the temporal variables of VO2 response at, and after, a time sustained at the exercise intensity corresponding to VO2max (Tlim) in different exercise modes. Forty-five trained male swimmers (11), rowers (13), runners (10) and cyclists (11) completed an incremental protocol to determine the velocity (vVO2max) or power (wVO2max) at VO2max and a square wave exercise from rest to 100% of vVO2max/wVO2max. The temporal variables of VO2 response were examined using a breath-by-breath gas analyzer. VO2 responses were not different between exercise modes, except for the percentage of VO2max at 50% of Tlim, which was ~6% higher in rowing compared to cycling (97.70±2.90 vs 92.40±5.69%, p=0.013). During the recovery period, both swimmers and rowers evidenced higher percentages of VO2max compared to cyclists at 30 s (65.1±10.4 and 65.7±5.6 vs 52.7±5.6%) and 60 s (41.7±10.8 and 38.4±5.4 vs 30.4±1.8%) time periods, all for p<0.01. Furthermore, swimmers presented higher time values to reach 50% VO2max compared to runners and cyclists (51.1±15.6 vs 38.1±6.7 and 33.8±4.7%; p<0.001). When training at 100% of VO2max intensity, fixed intervals for HIIT could be set freely. However, recovery periods based on time or intensity are exercise-mode dependent.
- Influence of Prior Exercise on VO2 Kinetics Subsequent Exhaustive Rowing PerformancePublication . Sousa, Ana; Ribeiro, João; Sousa, Marisa; Vilas-Boas, João Paulo; Fernandes, Ricardo J.Prior exercise has the potential to enhance subsequent performance by accelerating the oxygen uptake (VO2) kinetics. The present study investigated the effects of two different intensities of prior exercise on pulmonary VO2 kinetics and exercisetime during subsequent exhaustive rowing exercise. It was hypothesized that in prior heavy, but not prior moderateexercise condition, overall VO2 kinetics would be faster and the VO2 primary amplitude would be higher, leading to longerexercise time at VO2max. Six subjects (mean 6 SD; age: 22.964.5 yr; height: 181.267.1 cm and body mass: 75.563.4 kg)completed square-wave transitions to 100% of VO2max from three different conditions: without prior exercise, with priormoderate and heavy exercise. VO2 was measured using a telemetric portable gas analyser (K4b2, Cosmed, Rome, Italy) andthe data were modelled using either mono or double exponential fittings. The use of prior moderate exercise resulted in afaster VO2 pulmonary kinetics response (t1 = 13.4163.96 s), an improved performance in the time to xhaustion(238.8650.2 s) and similar blood lactate concentrations ([La2]) values (11.861.7 mmol.L21) compared to the onditionwithout prior exercise (16.065.56 s, 215.3660.1 s and 10.761.2 mmol.L21, for t1, time sustained at VO2max and [La2], respectively). Performance of prior heavy exercise, although useful in accelerating the VO2 pulmonary kinetics responseduring a subsequent time to exhaustion exercise (t1 = 9.1861.60 s), resulted in a shorter time sustained at VO2max(155.5646.0 s), while [La2] was similar (13.561.7 mmol.L21) compared to the other two conditions. Although both priormoderate and heavy exercise ulted in a faster pulmonary VO2 kinetics response, only prior moderate exercise lead to improved rowing performance.
- VO2 at Maximal and Supramaximal Intensities: Lessons to High-Intensity Interval Training in SwimmingPublication . Sousa, Ana; Vilas-Boas, João Paulo; Fernandes, Ricardo J.; Figueiredo, PedroTo establish appropriate work intensity for interval training that would elicit maximal oxygen uptake (VO2max) for well-trained swimmers.