Effects of The Performance Level and Race Distance on Pacing in Ultra-Triathlons.

The aim of this study was to examine the effects of the performance level and race distance on pacing in ultra-triathlons (Double, Triple, Quintuple and Deca), wherein pacing is defined as the relative time (%) spent in each discipline (swimming, cycling and running). All finishers (n = 3,622) of Double, Triple, Quintuple and Deca Iron ultra-triathlons between 1985 and 2016 were analysed and classified into quartile groups (Q1, Q2, Q3 and Q4) with Q1 being the fastest and Q4 the slowest. Performance of all non-finishers (n = 1,000) during the same period was also examined. Triple and Quintuple triathlons (24.4%) produced the highest rate of non-finishers, and Deca Iron ultra-triathlons produced the lowest rate (18.0%) (χ2 = 12.1, p = 0.007, φC = 0.05). For the relative swimming and cycling times (%), Deca triathletes (6.7 ± 1.5% and 48.8 ± 4.9%, respectively) proved the fastest and Double (9.2 ± 1.6% and 49.6 ± 3.6%) Iron ultra-triathletes were the slowest (p < 0.008) with Q4 being the fastest group (8.3 ± 1.6% and 48.8 ± 4.3%) and Q1 the slowest one (9.5 ± 1.5% and 50.9 ± 3.0%) (p < 0.001). In running, Double triathletes were relatively the fastest (41.2 ± 4.0%) and Deca (44.5 ± 5.4%) Iron ultra-triathletes the slowest (p < 0.001) with Q1 being the fastest (39.6 ± 3.3%) and Q4 the slowest group (42.9 ± 4.7%) (p < 0.001). Based on these findings, it was concluded that the fastest ultra-triathletes spent relatively more time swimming and cycling and less time running, highlighting the importance of the role of the latter discipline for the overall ultra-triathlon performance. Furthermore, coaches and ultra-triathletes should be aware of differences in pacing between Double, Triple, Quintuple and Deca Iron triathlons.

Sex difference in open-water swimming-The Triple Crown of Open Water Swimming 1875-2017.

The aim of the present study was to compare swimming performances of successful finishers of the 'Triple Crown of Open Water Swimming' from 1875 to 2017, assessing the effects of sex, the place of event and the nationality of swimmers. Data from 535 finishers in 'Catalina Channel Swim', 1,606 finishers in 'English Channel Swim' and 774 finishers in 'Manhattan Island Marathon Swim' were analysed. We performed different analyses and regression model fittings for all swimmers and annual top-5 finishers. Effects (sex, event, time, nationality) and interaction terms (event-time) were examined through a multi-variable spline mixed regression model. Considering all swimmers, we found that (i) women were approximately 0.06 km/h faster than men (p = 0.011) and (ii) Australians were 0.13 km/h faster than Americans (p = 0.004) and Americans were 0.19 km/h faster than British (p<0.001) and 0.21 km/h faster than Canadians (p = 0.015). When considering annual top-5 finishers, we found that (i) women were 0.07 km/h slower than men (p = 0.042) and (ii) Australians were not faster than Americans (p = 0.149) but Americans were 0.21 km/h faster than British (p<0.001). Our findings improved the knowledge about swim performances over time, in the three events, considering the effects of sex and the nationality of swimmers.

The Antioxidant Effect of Exercise: A Systematic Review and Meta-Analysis.

BACKGROUND: Physical activity has been associated with reduced oxidative stress (OS) in observational studies and clinical trials. OBJECTIVE: The purpose of this systematic review and meta-analysis of controlled trials was to determine the effect of physical exercise on OS parameters. METHODS: We conducted a systematic review of the literature up to March 2016 that included the following databases: PubMed, SCOPUS, and Web of Science. A keyword combination referring to exercise training and OS was included as part of a more thorough search process. We also manually searched the reference lists of the articles. From an initial 1573 references, we included 30 controlled trials (1346 participants) in the qualitative analysis, 19 of which were included in the meta-analysis. All trials were conducted in humans and had at least one exercise intervention and a paired control group. Using a standardized protocol, two investigators independently abstracted data on study design, sample size, participant characteristics, intervention, follow-up duration, outcomes, and quantitative data for the meta-analysis. Thus, the investigators independently assigned quality scores with a methodological quality assessment (MQA). RESULTS: The agreement level between the reviewers was 85.3 %. Discrepancies were solved in a consensus meeting. The MQA showed a total score in the quality index between 40 and 90 % and a mean quality of 55 %. Further, in a random-effects model, data from each trial were pooled and weighted by the inverse of the total variance. Physical training was associated with a significant reduction in pro-oxidant parameters (standard mean difference [SMD] -1.08; 95 % confidence interval [CI] -1.57 to -0.58; p < 0.001) and an increase in antioxidant capacity (SMD 1.45; 95 % CI 0.83-2.06; p < 0.001). CONCLUSION: The pooled analysis revealed that regardless of intensity, volume, type of exercise, and studied population, the antioxidant indicators tended to increase and pro-oxidant indicators tended to decrease after training. Therefore, we conclude that exercise training seems to induce an antioxidant effect. Thus, it is suggested that people practice some kind of exercise to balance the redox state, regardless of their health status, to improve health-related outcomes.