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In this article, the author talks about her National swimmer career and career in law in South Africa. Topics discussed include her selection for open water swim at the Senior African Champs in Morocco, her participation in the London Olympic Games and her swimming training under the guidance of National Head Coach Graham Hill.

The pressure forces predominate Hydrodynamic forces are the result of pressure component (perpendicular to surfaces) and friction component (tangential to surfaces). To be effective, the swimmers will, as soon as possible and as long as possible, direct their hand and forearm perpendicular to the forward direction to direct the hydrodynamic forces in the forward direction. For instance Kudo et al. in 2013 have shown hydrodynamic forces on the accelerating hand were between 1.9 and 10 times greater than for the non-accelerating hand. [Extracted from the article]

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. [ABSTRACT FROM AUTHOR]

Whether the large lungs of swimmers result from intensive training or genetic endowment has been widely debated. Given that peak lung growth velocities occur during puberty, this study examined if competitive swimming during puberty affected lung growth. Eleven- to fourteen-year-old healthy female competitive swimmers and controls were assessed before (PRE) and after (POST) one swimming season (7.4 ± 0.5 months). Pulmonary function testing included lung volumes, spirometry, diffusion capacity (DL,CO), and maximal inspiratory (PIMAX) and expiratory (PEMAX) pressures. Ventilatory constraints, including end-expiratory lung volume, expiratory flow limitation, and utilization of ventilatory capacity, were assessed during an incremental cycling test. Swimmers (n = 11) and controls (n = 10) were of similar age, size, and sexual maturity (P > 0.05). However, swimmers compared to controls had a greater total lung capacity (PRE 4.73 ± 0.73 vs. 3.93 ± 0.46, POST 5.08 ± 0.68 vs. 4.19 ± 0.64 L; P < 0.01), peak expiratory flow (PRE 6.48 ± 0.92 vs. 5.70 ± 0.86, POST 6.97 ± 0.84 vs. 6.00 ± 0.77 L•s-1; P = 0.03), and PEMAX (P < 0.001). Although DL,CO was greater in swimmers (P = 0.01), differences were attenuated when expressed relative to alveolar volume (PRE 5.14 ± 0.60 vs. 5.44 ± 0.44, POST 4.91 ± 0.56 vs. 5.16 ± 0.38 mL min-1 mmHg-1 L-1; P = 0.20). The groups achieved a similar maximal oxygen uptake (P = 0.32), and ventilatory constraints experienced were not different (P > 0.05). Changes over time were not different between groups (P > 0.05). At the initial measurement, pubertal female swimmers had greater lung size, expiratory flows, and indices of respiratory muscle strength, but similar ventilatory constraints while cycling. One competitive swimming season did not further accentuate this enhanced lung size and function or alter ventilatory mechanics, suggesting that competitive swimming during puberty did not affect lung growth. [ABSTRACT FROM AUTHOR]

Fish in schooling formations navigate complex flow fields replete with mechanical energy in the vortex wakes of their companions. Their schooling behavior has been associated with evolutionary advantages including energy savings, yet the underlying physical mechanisms remain unknown. We show that fish can improve their sustained propulsive efficiency by placing themselves in appropriate locations in the wake of other swimmers and intercepting judiciously their shed vortices. This swimming strategy leads to collective energy savings and is revealed through a combination of high-fidelity flow simulations with a deep reinforcement learning (RL) algorithm. The RL algorithm relies on a policy defined by deep, recurrent neural nets, with long-short-term memory cells, that are essential for capturing the unsteadiness of the two-way interactions between the fish and the vortical flow field. Surprisingly, we find that swimming in-line with a leader is not associated with energetic benefits for the follower. Instead, "smart swimmer(s)" place themselves at off-center positions, with respect to the axis of the leader(s) and deform their body to synchronize with the momentum of the oncoming vortices, thus enhancing their swimming efficiency at no cost to the leader(s). The results confirm that fish may harvest energy deposited in vortices and support the conjecture that swimming in formation is energetically advantageous. Moreover, this study demonstrates that deep RL can produce navigation algorithms for complex unsteady and vortical flow fields, with promising implications for energy savings in autonomous robotic swarms. [ABSTRACT FROM AUTHOR]

Assigning swimmers to events in order to maximize global performance of the team in a multi-team meeting is not a trivial issue for coaches. In fact, often months of hard work and training is wasted if a mistake is made in the line-up decision process. Expert coaches use their long time experience in order to make correct decisions, but often without reaching an optimal assignment. Athletes preferences also affect the decision process making coaches job even harder and, furthermore, the actual goal to be achieved may vary among situations. In this paper two different integer programming models, based on an estimation of opponents performances capability, constructed following two different philosophies and addressing two different situations are proposed. The first model just maximizes the total score obtained by the team, while the second model aim to optimize the placement achieved by the team in the meeting final ranking and the advantage on the first follower in the ranking. A detailed analysis of good and bad points of the two approaches and of situations in which one approach may be preferred respect to the other is reported. A real case example, taken from an Italian Regional Master Meeting, is deeply analyzed and a discussion on the comparison among results obtained with the assignment provided by the two models and the actual lineup proposed by the coach, is provided. [ABSTRACT FROM AUTHOR]

Background: The pycnodontiform fish Pycnodus is one of the representatives of the highly diverse actinopterygian fish fauna from the early Eocene Bolca Lagersta¨tte, representing one of the youngest and thus last occurrences of this extinct neopterygian clade. This genus has historically been used as a wastebasket taxon in regards to poorly known pycnodontiform fossils. Authors have argued over the specific status of the Bolca Lagersta¨tte Pycnodus in terms of how many species are contained within the genus with some arguing for multiple species and others suggesting lumping all Bolca specimens together into one species. Methods: Here, we use a quantitative approach performing biometric and geometric morphometric analyses on 52 specimens of Pycnodus in order to determine if the morphological variability within the sample might be related to inter- or intraspecific variation. Results: The analyses revealed that the variations of body shape, morphometric and meristic characters cannot be used to distinguish different morphotypes. On the contrary, our results show a remarkable link between shape and size, related to ontogeny. Discussion: Differences in body shape of small (juvenile) and large (adult) individuals is probably related to different microhabitats occupation on the Bolca reef with juveniles sheltering within crevices on the reef and adults being more powerful swimmers that swim above the coral. Taxonomically, we suggest that the Bolca Pycnodus should be referred to strictly as Pycnodus apodus as this was the name given to the holotype. Additionally, an overview of species assigned to Pycnodus is given. [ABSTRACT FROM AUTHOR]

Generalised Joint Hypermobility including shoulder hypermobility (GJHS) in swimmers is considered an intrinsic risk factor for shoulder injuries. The aim was to investigate the association of GJHS with shoulder strength, fatigue development and muscle activity during swimming-related shoulder rotations. Totally, 38 competitive swimmers (aged 13-17 years) participated, 19 were competitive swimmers with GJHS and 19 were age, sex and club matched swimmers without GJHS. Concentric isokinetic force in medial and lateral rotations were measured at 60°/s (5 repetitions) and 180°/s (10 repetitions). Electromyographic activity was measured from upper trapezius, lower trapezius, serratus anterior, infraspinatus and pectoralis major muscles. Swimmers with GJHS produced significantly lower peak torque (0.53 vs. 0.60 Nm/kg; p = .047) and maximum work (0.62 vs. 0.71 J/kg; p = .031) than controls during medial rotation (60°/s). Swimmers with GJHS showed significantly larger isokinetic fatigue at 180°/s (0.321 J/repetition; p = .010), and tendencies to lower levels of muscle activity in infraspinatus (20%, p = .066) and pectoralis major (34%, p = .092) at 60°/s during medial rotation. Young competitive swimmers with GJHS, despite no formal diagnosis, displayed strength and fatigue deficits in medial rotation, potentially inherent with greater risk of shoulder injury. Whether GJHS swimmers benefit from medial rotation strengthening is an important topic for future studies. [ABSTRACT FROM AUTHOR]

The primary goal was to determine whether the achievement of finalist positions in the Junior Championship was associated with the achievement of success in the International Swimming Federation (FINA) World Championship (WC). Secondary goals included analyzing the effect of various factors (gender, age, country, etc) on swimmers’ performances. Data were obtained from FINA information about the finalists from 2007 to 2015 WCs and finalists from 2006 to 2013 Junior-WCs (2400 entries). Final filtered database just included swimmers who participated in both junior and senior WCs (719 entries). A univariate general linear model (GLM) was used to examine the association between time; origin (swimmer who participated in Junior WC or not); maintenance years (number of years achieving finalist positions); country; and age, adjusting for year of competition. An ordinal logistic regression (OLR) model was used to identify predictors of achieving the top positions. The origin variable was not significant in either the GLM or the OLR. The only significant variables in the GLM were maintenance years (F4,706 = 7.689; p < .05) and year of competition (F4,706 = 23.239; p < .05). The OLR revealed a strong association (p < .001) between the position variable and maintenance years, getting better positions as you get more WCs (odds = 1.85). In conclusion, no evidence was obtained to conclude finalist position in Junior WC have influence in achieve success in FINA WC. Maintenance years in WCs have a positive impact to achieve better positions. [ABSTRACT FROM AUTHOR]

No research has been published on the characteristics and behavior patterns of athletes traveling to compete in open water swimming events, despite the growing popularity of such events. This article fills this gap by profiling nonresident competitors in the Waikiki Roughwater Swim, an iconic community-based event held annually on the Hawaiian island of Oahu. Data were collected in an intercept survey of swimmers shortly after they finished the race. Nonresident competitors in the event were found to be a viable market segment according to established criteria for such viability. Their significant numbers and high incomes evidenced their potential profitability and their high levels of affiliation with swimming organizations suggested that personal selling to the organizations' leaders and advertising via the organizations' newsletters and websites might be effective channels through which to reach them. In addition, their high levels of education, athletic identity, experienced "flow," involvement with open water swimming, and importance ascribed to swimming "the famous Waikiki coastline" suggested that advertisements directed at them should be designed to resonate with welleducated, accomplished, and committed athletes, include reminders of the psychological and social benefits of race participation, and explicitly mention the event's unique and attractive geographic and historical setting. [ABSTRACT FROM AUTHOR]

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Purpose: It is important that competitive swimmers follow adequate nutritional planning periodized according to their training program. The aim of this study was to assess daily energy and macronutrient intake, and its adequacy to the exercise sessions in high-performance swimmers. Methods: Dietary intake of 16 swimmers (11 men and 5 women; 15-25 years) was assessed using a 3-day food record in the first phase of the training program (two swimming sessions and one complementary training every day). Daily energy expenditure and energy balance were calculated using predictive equation. Results: A daily energy deficit was found in 80% ( n = 4) of women and in 18.2% ( n = 2) of men. Daily protein intake was higher than recommended in men (2.2, s = 0.4 g/kg/day; p = 0.006, d = 1.25), and a low fat intake was observed in women (1.1, s = 0.1 g/kg/day; p = 0.001, d = 4.00). Carbohydrate intake was low for most male and female swimmers related to training sessions. Morning training had 20% ( n = 1) of women and 18.2% ( n = 2) of men consuming adequate carbohydrate before training. In the afternoon, only 20% ( n = 1) of women achieved the recommendations before training sessions, and none of the swimmers achieved the recommendations for carbohydrate plus protein intake in the afternoon post-exercise period. Conclusions: The findings of this study suggest: (1) most of these men consumed energy and macronutrient according to their daily requirements; (2) most of these women failed on daily energy and fat intake; (3) most of these swimmers did not achieve nutrient goals on meals near exercise, especially in the second exercise of the day. [ABSTRACT FROM AUTHOR]

The main objective of this research was to evaluate the efficacy of intermittent hypoxic training (IHT) on anaerobic and aerobic capacity and swimming performance in well-trained swimmers. Sixteen male swimmers were randomly divided into a hypoxia (H) group (n = 8), which trained in a normobaric hypoxia environment, and a control (C) group (n = 8), which exercised under normoxic conditions. However, one participant left the study without explanation. During the experiment group H trained on land twice per week in simulated hypoxia (FiO2 = 15.5%, corresponding to 2,500 m a.s.l); however, they conducted swim training in normoxic conditions. Group C performed the same training program under normoxic conditions. The training program included four weekly microcyles, followed by three days of recovery. During practice sessions on land, the swimmers performed 30 second sprints on an arm-ergometer, alternating with two minute high intensity intervals on a lower limb cycle ergometer. The results showed that the training on land caused a significant (p<0.05) increase in absolute maximal workload (WRmax) by 7.4% in group H and by 3.2% in group C and relative values of VO2max by 6.9% in group H and 3.7% in group C. However, absolute values of VO2max were not significantly changed. Additionally, a significant (p<0.05) increase in mean power (Pmean) during the first (11.7%) and second (11.9%) Wingate tests was only observed in group H. The delta values of lactate concentration (ΔLA) after both Wingate tests were significantly (p<0.05) higher in comparison to baseline levels by 28.8% in group H. Opposite changes were observed in delta values of blood pH (ΔpH) after both Wingate tests in group H, with a significant decrease in values of ΔpH by 33.3%. The IHT caused a significant (p<0.05) improvement in 100m and 200m swimming performance, by 2.1% and 1.8%, respectively in group H. Training in normoxia (group C), resulted in a significant (p<0.05) improvement of swimming performance at 100m and 200m, by 1.1% and 0.8%, respectively. In conclusion, the most important finding of this study includes a significant improvement in anaerobic capacity and swimming performance after high-intensity IHT. However, this training protocol had no effect on absolute values of VO2max and hematological variables. [ABSTRACT FROM AUTHOR]

The purpose of this investigation was to determine which foot stance, the track start (TS) or the grab start (GS), is most beneficial for competitive swimmers. Seven male and eight female collegiate swimmers participated in this study. The average participant age was 20.1 ± 1.13 years while the average years of competitive swimming experience was 10.8 ± 3.36 years. Participants performed three TS and three GS stances consecutively. Distance markers were placed on the side of the pool to determine where each swimmer entered the water. Video analysis was used to determine the following factors: start phase time, flight phase time, flight distance, horizontal entrance velocity, and entrance angle. Prior to participating in the study, swimmers completed a brief survey regarding age and competitive swimming experience, and researchers measured each participant's height and weight. A paired sample T-test was used to determine significant differences between the GS and TS. The results indicated that the TS foot stance resulted in a shorter start phase time (0.76 ± 0.07 s vs. 0.88 ± 0.10 s; P < 0.001), a shorter flight phase time (0.81 ± 0.08 vs. 0.95 ± 0.07; P < 0.001), and a greater horizontal entrance velocity (3.56 ± 0.51 m/s vs. 3.10 ± 0.41 m/s; P < 0.001). The GS allowed swimmers to travel further in the air (2.96 ± 0.43 m vs. 2.88 ± 0.41 m; P = 0.013). The TS entrance angle was significantly shallower than the GS entrance angle (36.98 ± 3.17° vs. 38.53 ± 3.81°; P = 0.004). Based on the results, the TS foot stance provides swimmers with the greatest advantage. [ABSTRACT FROM AUTHOR]

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