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Rowing races require extreme physical and psychological effort from every athlete. This study aimed to determine the dynamics of the salivary cortisol and alpha-amylase, as well as blood lactate throughout the specific load represented by a 6 km rowing race, conducted on a rowing ergometer. The sample consisted of 11 junior and senior rowers from HVK Gusar in Split (n = 11) who actively competed at club and international levels. Variables consisted of three repeated oral samples of the hormone cortisol and the enzyme alpha-amylase determined in saliva and three repeated blood lactate samples. Potential differences in the levels of the studied variables at different time points were determined using a repeated-measures ANOVA test. The results showed different dynamics of hormonal (cortisol) and metabolic (alpha-amylase and lactates) variables. All variables experienced a significant post-race increase, while other changes were not significant. The results highlighted that high-intensity rowing causes an increase in the body’s cortisol, alpha-amylase, and lactate levels. This should be implemented in rowing training to find the right balance between high and low-intensity rowing, enabling athletes’ progression while reducing the risk of overtraining.

This longitudinal study aimed to analyze the effects of a team rowing-based training program on physical fitness and anthropometric parameters in female breast cancer survivors (n = 40; 56.78 ± 6.38 years). Participants were divided into two groups: one rowed in fixed seat rowing (FSR) boats (n = 20; 56.35 ± 4.89 years) and the other in sliding seat rowing (SSR) boats (n = 20; 57.20 ± 7.7 years). Both groups engaged in two 75-min sessions per week for 24 weeks. Significant improvements were observed in both groups in resting heart rate (FSR: −10.65 bpm; SSR: −8.45 bpm), heart rate at the beginning of the 6-min walk test (6 MWT) (FSR: −10.7 bpm; SSR: −11.25 bpm), and heart rate at the end of the test (FSR: −13.85 bpm; SSR: −20.35 bpm). Blood pressure improved significantly in both diastolic blood pressure (FSR: −12.35 mmHg; SSR: −19.25 mmHg) and systolic blood pressure (FSR: −13 mmHg; SSR: −16.95 mmHg). Additionally, both groups increased the distance covered in the 6 MWT (FSR: +63.05 m; SSR: +93.65 m). These results suggest that a rowing training program is a viable and safe activity for female breast cancer survivors, improving cardiac function, blood pressure, and cardiorespiratory capacity, particularly in sliding seat boats.

For athletes to gain body mass, especially muscle, an increase in energy consumption is necessary. To increase their energy intake, many athletes consume more meals, including supplementary meals or snacks. However, the influence of meal frequency on changes in body composition and appetite is unclear. The aim of this study was to determine the effect of meal frequency on changes in body composition and appetite during weight gain in athletes through a well-controlled dietary intervention. Ten male collegiate rowers with weight gain goals were included in this study. The subjects were randomly classified into two groups, and dietary intervention was implemented using a crossover method. During the intervention period, all subjects were provided identical meals aimed to provide a positive energy balance. The meals were consumed at a frequency of either three times (regular frequency) or six times (high frequency) a day. Body composition was measured using dual energy X-ray absorptiometry, and the visual analog scale was used for the evaluation of appetite. In both trials, body weight, fat-free mass, and fat mass significantly increased; however, an interaction (Trial × Time) was not observed. Visual analog scale did not vary between trials. Our data suggest that partitioning identical excess dietary intakes over three or six meals does not influence changes in body composition or appetite during weight gain in athletes. [ABSTRACT FROM AUTHOR]

Purpose: To examine the relationship between the maximal power output (MPO) in an individualized 7 x 2-minute incremental (INCR) test, average power in a 2k (W2k) rowing ergometer test, and maximal oxygen uptake (VO2max) and to develop a regression equation to predict VO2max. Methods: A total of 34 male club rowers (age 18-30 y) performed a 2k and an INCR test in a Concept2 rowing ergometer to determine and compare MPO, W2k, and VO2max. Results: No significant difference was found between VO2max measured during INCR or 2k test (P = .73). A very high correlation coefficient (r = .96) was found between MPO and VO2max and between W2k and VO2max (r = .93). Linear regression analyses were developed for predicting VO2max from MPO: (1) VO2max (mL·min-1) = 11.49 x MPO + 810 and VO2max from W2k: (2) VO2max = 10.96 x W2k + 1168. Cross-validation analyses were performed using an independent sample of 14 rowers. There was no difference between the mean predicted VO2max in the INCR test (4.41 L·min-1) or the 2k test (4.39 L·min-1) and the observed VO2max (4.40 L·min-1). Technical error of measurement was 3.1% and 3.6%, standard error of estimate was 0.136 and 0.157 mL·min-1, and validation coefficients (r) were .95 and .94 using Equation (1) and (2), respectively. Conclusion: A prediction model only including MPO or W2k explains 88% to 90% of the variability in VO2max and is suggested for practical use in male club rowers. [ABSTRACT FROM AUTHOR]

Purpose: To test whether the force–velocity (F–V) relationship obtained during a specific single-stroke kayak test (SSKT) and during nonspecific traditional resistance-training exercises (bench press and prone bench pull) could discriminate between 200-m specialists and longer-distance (500- and 1000-m) specialists in canoe sprint. Methods: A total of 21 experienced male kayakers (seven 200-m specialists and 14 longer-distance specialists) participated in this study. After a familiarization session, kayakers came to the laboratory on 2 occasions separated by 48 to 96 hours. In a randomized order, kayakers performed the SSKT in one session and the bench press and bench pull tests in another session. Force and velocity outputs were recorded against 5 loads in each exercise to determine the F–V relationship and related parameters (maximum force, maximum velocity, F–V slope, and maximum power). Results: The individual F–V relationships were highly linear for the SSKT (r =.990 [.908,.998]), bench press (r =.993 [.974,.999]), and prone bench pull (r =.998 [.992, 1.000]). The F–V relationship parameters (maximum force, maximum velocity, and maximum power) were significantly higher for 200-m specialists compared with longer-distance specialists (all Ps ≤.047) with large effect sizes (≥0.94) revealing important practical differences. However, no significant differences were observed between 200-m specialists and longer-distance specialists in the F–V slope (P ≥.477). Conclusions: The F–V relationship assessed during both specific (SSKT) and nonspecific upper-body tasks (bench press and bench pull) may distinguish between kayakers specialized in different distances. [ABSTRACT FROM AUTHOR]

Purpose: Rowers can be in marshaling areas for up to 20 to 25 min before the start of a race, which likely negates any benefits of an active warm-up, especially in cold environments. It is unknown if using a heated jacket following a standardized rowing warm-up can improve 2000-m rowing performance. Methods: On 2 separate occasions, 10 trained male rowers completed a standardized rowing warm-up, followed by 25 min of passive rest before a 2000-m rowing time trial on a rowing ergometer. Throughout the passive rest, the participants wore either a standardized tracksuit top (CON) or an externally heated jacket (HEAT). The trials, presented in a randomized crossover fashion, were performed in a controlled environment (temperature 8°C, humidity 50%). Rowing time-trial performance, core body temperature, and mean skin temperature, along with perceptual variables, were measured. Results: During the 25-min period, core body temperature increased in HEAT and decreased in CON (Δ0.54°C [0.74°C] vs −0.93°C [1.14°C]; P =.02). Additionally, mean skin temperature (30.22°C [1.03°C] vs 28.86°C [1.07°C]) was higher in HEAT versus CON (P <.01). In line with the physiological data, the perceptual data confirmed that participants were more comfortable in HEAT versus CON, and subsequently, rowing performance was improved in HEAT compared with CON (433.1 [12.7] s vs 437.9 [14.4] s, P <.01). Conclusion: The data demonstrate that an upper-body external heating garment worn following a warm-up can improve rowing performance in a cool environment. [ABSTRACT FROM AUTHOR]

Background The mechanical properties of muscles, such as changes in muscle tone and stiffness, are related to sports performance and injuries. Rowers are at increased risk of muscle fatigue and injury during high-repetition and heavy-load cyclic muscle actions. In view of this, the aim of the present study was to investigate the acute effect on muscle tone and stiffness, as well as bilateral muscle asymmetry, in high school rowers after a 2000-meter rowing ergometer test. Methods Twelve young male rowers (age = 17.1 ± 0.9 years, body weight = 73.5 ± 9.7 kg) were included in the study. The data of muscle tone (frequency) and stiffness of the posterior deltoids (PD), latissimus dorsi (LD), and rectus femoris (RF) (dominant and non-dominant side) before and after a 2000-m rowing ergometer test were collected using a handheld MyotonPRO device. Results After the rowing ergometer test, the muscle tone of dominant side PD, LD, and RF were significantly increased (p < 0.05). On the other hand, the muscle stiffness of the non-dominant side LD and RF, as well as the dominant side PD, LD, and RF were significantly increased after the rowing ergometer test (p < 0.05). The muscle tone and stiffness results showed that the dominant side PD, LD, and RF were all significantly higher than the non-dominant side after the rowing ergometer test (p < 0.05), where bilateral PD and RF exhibits moderate asymmetry (5% < symmetry index < 10%). Conclusions After a high-intensity and high-load 2000-m rowing ergometer test, PD, LD, and RF showed increases in muscle tone and stiffness, as well as changes in the symmetry of bilateral muscle mechanical properties.

Purpose: To compare the metabolic cost of paddling on different commercially available kayak ergometers using a standardized kayak incremental exercise protocol. Methods: Six male sprint kayak athletes undertook an incremental exercise protocol on 3 different kayak ergometers utilizing a randomized counterbalanced pair-matched design. Results: Mean maximal aerobic power on the WEBA ergometer (265 [14] W) was significantly higher than on the Dansprint (238 [9] W) and KayakPro® (247 [21] W, P <.01, effect size [ES] = 0.80). At the fifth stage, absolute oxygen consumption on the WEBA (3.82 [0.25] L·min−1) was significantly lower (P < 0.05, ES = 0.20) than KayakPro and Dansprint (4.10 [0.28] and 4.08 [0.27] L·min−1, respectively). Blood lactate concentration response at the sixth stage was significantly lower for the WEBA (3.5 [0.8] mmol·L−1), compared with KayakPro and Dansprint (5.4 [1.2] and 5.6 [1.5] mmol·L−1, P =.012, ES = 0.20). Stroke rate was significantly higher, without any effect of pacing during the submaximal stages for the Dansprint, compared with the WEBA (P <.001, ES = 0.28) and KayakPro (P <.001, ES = 0.38). A pacing effect was present at the maximal stage for all ergometers. Conclusions: This study demonstrated that paddling on different kayak ergometers when controlling power output elicits different metabolic and work outputs. It is recommended that scientists and coaches avoid testing on different ergometers and regularly calibrate these devices. Moreover, when an ergometer has been calibrated against a first principle device, it is necessary to consider calibration of various drag settings, due to their impact on stroke rate. Further research should explore the relationship between drag settings and stroke rate. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine the interrater reliability of a new evidence-based classification system for Para Va'a. Twelve Para Va'a athletes were classified by three classifier teams each consisting of a medical and a technical classifier. Interrater reliability was assessed by calculating intraclass correlation for the overall class allocation and total scores of trunk, leg, and on-water test batteries and by calculating Fleiss's kappa and percentage of total agreement in the individual tests of each test battery. All classifier teams agreed with the overall class allocation of all athletes, and all three test batteries exhibited excellent interrater reliability. At a test level, agreement between classifiers was almost perfect in 14 tests, substantial in four tests, moderate in four tests, and fair in one test. The results suggest that a Para Va'a athlete can expect to be allocated to the same class regardless of which classifier team conducts the classification. [ABSTRACT FROM AUTHOR]

Context: Pain in sport has been normalized to the point where athletes are expected to ignore pain and remain in the game despite the possible detrimental consequences associated with playing through pain. While rehabilitation specialists may not have an influence on an athlete's competitive nature or the culture of risk they operate in, understanding the consequences of those factors on an athlete's physical well-being is definitely in their area of responsibility. Objective: To explore the factors associated with the experiences of subelite athletes who play through pain in gymnastics, rowing, and speed skating. Design: The authors conducted semistructured interviews with subelite athletes, coaches, and rehabilitation specialists. They recruited coach participants through their provincial sport organization. Athletes of the recruited coaches who were recovering from a musculoskeletal injury and training for a major competition were then recruited. They also recruited rehabilitation specialists who were known to treat subelite athletes independently by e-mail. Setting: An observation session was conducted at the athlete's training facility. Interviews were then conducted either in a room at the university or at a preferred sound-attenuated location suggested by the participant. Participants: The authors studied 5 coaches, 4 subelite athletes, and 3 rehabilitation specialists. Interventions: The authors photographed athletes during a practice shortly before an important competition, and we interviewed all the participants after that competition. Our photographs were used during the interview to stimulate discussion. Results: The participant interviews revealed 3 main themes related to playing through pain. They are: Listening to your body, Decision making, and Who decides. Conclusion: When subelite athletes, striving to be the best in their sport continue to train with the pain of an injury, performance is affected in the short-term and long-term consequences are also possible. Our study provides some insight into the contrasting forces that athletes balance as they decide to continue or to stop. [ABSTRACT FROM AUTHOR]

Purpose: To compare methods of monitoring and prescribing on-water exercise intensity (heart rate [HR], stroke rate [SR], and power output [PO]) during sprint kayak training. Methods: Twelve well-trained flat-water sprint kayak athletes completed a preliminary on-water 7 × 4-min graded exercise test and a 1000-m time trial to delineate individual training zones for PO, HR, and SR into a 5-zone model (T1–T5). Subsequently, athletes completed 2 repeated trials of an on-water training session, where intensity was prescribed based on individual PO zones. Times quantified for T1–T5 during the training session were then compared between PO, HR, and SR. Results: Total time spent in T1 was higher for HR (P <.01) compared with PO. Time spent in T2 was lower for HR (P <.001) and SR (P <.001) compared with PO. Time spent in T3 was not different between PO, SR, and HR (P >.05). Time spent in T4 was higher for HR (P <.001) and SR (P <.001) compared with PO. Time spent in T5 was higher for SR (P =.03) compared with PO. Differences were found between the prescribed and actual time spent in T1–T5 when using PO (P <.001). Conclusions: The measures of HR and SR misrepresented time quantified for T1–T5 as prescribed by PO. The stochastic nature of PO during on-water training may explain the discrepancies between prescribed and actual time quantified for power across these zones. For optimized prescription and monitoring of athlete training loads, coaches should consider the discrepancies between different measures of intensity and how they may influence intensity distribution. [ABSTRACT FROM AUTHOR]

Background: Identifying strategies that reduce the risk of illness and injury is an objective of sports science and medicine teams. No studies have examined the relationship between oxidative stress (OS) and illness or injury in international athletes undergoing periods of intensified training and competition. Purpose: The authors aimed to identify relationships between illness, injury, and OS. Methods: A longitudinal, observational study of elite male rowers (n = 10) was conducted over 18 weeks, leading into World Championships. Following a recovery day and a 12-hour fast, hydroperoxides (free oxygen radicals test) and total antioxidant capacity (free oxygen radicals defense) were measured in venous blood, with the ratio calculated as the oxidative stress index (OSI). At all study time points, athletes were independently dichotomized as ill or not ill, injured or not injured. OS data were compared between groups using independent t tests. A Cox proportional hazard model was used to assess the association of OS with injury and illness while adjusting for age and body mass index. Results: Free oxygen radicals defense was lower (P <.02) and OSI was higher (P <.001) with illness than without illness. Free oxygen radicals test and OSI were higher with injury than without injury (P <.001). A 0.5 mmol·L−1 increase in free oxygen radicals defense was associated with a 30.6% illness risk reduction (95% confidence interval, 7%–48%, P =.014), whereas 0.5 unit increase in OSI was related to a 11.3% increased illness risk (95% confidence interval, 1%–23%, P =.036). Conclusions: OS is increased in injured and ill athletes. Monitoring OS may be advantageous in assessing recovery from and in reducing injury and illness risk given the association. [ABSTRACT FROM AUTHOR]

In cognitive-motor dual-task situations, the extent of performance decrements is influenced by the attentional requirements of each task. Well-learned motor skills should be automatized, leading to less interference. This study presents two studies combining an episodic memory encoding task with well-practiced motor tasks in athletes. Study 1 asked 40 rowers (early teenagers to middle adulthood) to row on ergometers at slow or fast speeds. In study 2, Taekwondo athletes (n = 37) of different skill levels performed a well-practiced sequence of martial arts movements. Performing the motor task during encoding led to pronounced performance reductions in memory in both studies, with costs of up to 80%. Cognitive costs were even larger when rowing with the fast compared to the slow speed in study 1. Both studies also revealed decrements in motor performances under dual-task conditions: Rowing became slower and more irregular (study 1), and the quality of the Taekwondo performance was reduced. Although higher-level athletes outperformed others in motor skills under single-task conditions, proportional dual-task costs were similar across skill levels for most domains. This indicates that even well-practiced motor tasks require cognitive resources. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine the effects of rowing stroke rates on lower extremity intra-joint coordination variability in professional rowers. Fifteen experienced young rowers volunteered to participate in this study. Kinematic data were recorded at different rowing speeds with seven Vicon cameras. The continuous relative phase (CRP) and CRP variability (CRPV) were used to calculate joint coordination and coordination variability, respectively, for the hip, knee, and ankle in the sagittal and horizontal planes, and a comparison was made among different rowing stroke rates. A vector analysis repeated measure ANOVA using statistical parametric mapping revealed that there were statistically significant differences in the hip–ankle, hip–knee, and knee–ankle CRPs for rowing at different stroke rates. Moreover, there was higher CRPV in the mid-drive and mid-recovery phases and less variability in the transition from the drive phase to the recovery phase. The results demonstrate the importance of knee joint in rowing tasks in experienced rowers during submaximal rowing stroke rate and the shift of movement to the hip at higher rowing stroke rate. Moreover, there was a smaller variability during drive-to-recovery transition, which may suggests an increased risk for overuse injuries. [ABSTRACT FROM AUTHOR]

Empirical observations support that the addition of a plastic strip – also known as Randall foils – on the top edge of a rowing blade improves rowing efficiency during the cycle propulsive phase. The aim of the current study was to analyze the effect of using big blades with and without Randall foils on rowing performance. Twenty experienced rowers performed two 90 s tethered rowing bouts (with and without Randall foils) to assess their impact on force production and physiologic variables. All tests were randomized and a repeated measure design was used to compare experimental conditions. Higher values of peak and mean peak forces (479.4±134.7 vs. 423.2±153.0, d =0.83 and 376.5±101.4 vs. 337.1±113.3 N, d =0.68), peak oxygen uptake (47.9±7.5 vs. 45.3±7.3 mL∙kg−1 ∙min−1 , d =0.19), peak blood lactate concentration (7.9±1.6 vs. 6.9±1.7 mmol∙L−1 , d =0.16), blood lactate increasing speed (0.08±0.01 vs. 0.07±0.06 [(mmol·L−1)·s−1 ], d =0.27) and lactic anaerobic energy (27.4±7.9 vs. 23.4±8.1 kJ, d =0.23) were found for big blades with vs. without Randall foils, p<0.05. The current data suggest that the Randall foils can positively affect rowing performance. [ABSTRACT FROM AUTHOR]

Aerobic metabolism dominates Olympic rowing, but research on the relative contribution of strength and power demands is limited. This study aimed to identify the contribution of different strength determinants for distinct phases of rowing ergometer performance. The crosssectional analysis comprised of 14 rowing athletes (4 female, 10 male, age: 18.8 ± 3.0y, 16.9 ± 2.2y). Measurements included anthropometrics, maximal strength of leg press, trunk extension and flexion, mid-thigh pull (MTP) and handgrip strength, VO2max, and a 2000 m time trial, where peak forces at the start, middle and end phase were assessed. Additionally, rate of force development (RFD) was assessed during the isometric leg press and MTP with intervals of 150, 350 ms and 150, 300 ms, respectively. Stepwise regression models for ergometer performance showed that the start phase was mainly explained by maximal trunk extension and RFD 300 ms of MTP (R² = 0.91, p < 0.001) and the middle section by VO2max, maximal leg press strength and sitting height (R² = 0.84, p < 0.001). For the end phase, a best fit was observed for trunk flexion, RFD 350 ms of leg press, body height and sex (R²= 0.97 p < 0.001), whereas absolute VO2max, trunk flexion and sex explained variance over the entire 2000 m time trial (R² = 0.98, p < 0.001). It appears that for the high acceleration in the start phase, force transmission through maximum strength for trunk extension is essential, while fast power production along the kinetic chain is also relevant. Additionally, the results support that maximal force complements the reliance on VO2max. Further intervention studies are needed to refine training recommendations. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to investigate the reliability of surface electromyography (EMG) assessed at seven muscles during three repeated 2000 m rowing ergometer sessions. Methods: Twelve male well-trained rowers participated in a repeated measures design, performing three 2000 m rowing ergometer sessions interspersed by 3–7 days (S1, S2, S3). Surface electrodes were attached to the gastrocnemius, biceps femoris, gluteus maximus, erector spinae, vastus medialis, rectus abdominis and latissimus dorsi for EMG analysis. Results: No differences existed between 2000 m sessions for EMG amplitude for any of the seven muscles (p = 0.146–0.979). Mean coefficient of variation of EMG for 6 of 7 muscles was 'acceptable' (12.3–18.6%), although classed as 'weak' for gastrocnemius (28.6%). Mean intra-class correlation coefficient values across muscles ranged from 'moderate' to 'very large' (0.31–0.89). Within-session EMG activation rates of vastus medialis were greater during 0–500 m and 1500–2000 m segments, compared with 500–1000 m and 1000–1500 m (p < 0.05). Values for biceps femoris and gluteus maximus were significantly higher during 1500–2000 m compared to 500–1000 m and 1000–1500 m (p < 0.05). The general pattern was for higher activation rates during 0–500 m and 1500–2000 m compared to 500–1000 m and 1000–1500 m. However, there were no between-sessions differences in EMG for any of the 500 m segments (p > 0.05). Conclusion: Reliability of EMG values over repeated 2000 m sessions was generally 'acceptable'. However, EMG was seemingly not sensitive enough to detect potential changes in neural activation between-sessions, with respect to changes in pacing strategy. [ABSTRACT FROM AUTHOR]

To quantify energy availability (EA) in elite female rowers, determine its association with bone mineral density (BMD), and examine the ability of the low energy availability in females-questionnaire (LEAF-Q) and brief eating disorder in athletes-questionnaire (BEDA-Q) to distinguish between low and normal EA. Observational cross-sectional study. Twenty-five elite female rowers participated in the study. EA was calculated by means of a 4-day food intake diary and analysis of training load. Low energy availability (LEA) was defined as EA < 30 kCal * kg−1 * FFM−1 * day−1. Dual-energy X-ray absorptiometry (DXA) was used to assess fat free mass (FFM) and BMD Z-scores. LEA risk was assessed using the LEAF-Q and BEDA-Q. The mean EA was 23.2 ± 12.2 kCal * kg−1 * FFM−1 * day−1. Prevalence of LEA was 64 %. The mean BMD Z-score was 1.6 ± 0.6 (range: 0.7 to 2.9). Athletes with LEA had a significantly higher BEDA-Q score than the group with normal EA (mean 0.30 ± 0.17 vs. 0.09 ± 0.11, P < 0.05), but LEAF-Q score was not different between groups (mean 10.4 ± 4.6, 8.2 ± 4.5, P = 0.29). Low energy availability is common amongst elite female rowers in New Zealand and is positively correlated with higher scores on the BEDA-Q. Bone mineral density was normal irrespective of EA status. [ABSTRACT FROM AUTHOR]

Metachronal rowing is a biological propulsion mechanism employed by many swimming invertebrates (e.g. copepods, ctenophores, krill and shrimp). Animals that swim using this mechanism feature rows of appendages that oscillate in a coordinated wave. In this study, we used observations of a swimming ctenophore (comb jelly) to examine the hydrodynamic performance and vortex dynamics associated with metachronal rowing. We first reconstructed the beating kinematics of ctenophore appendages based on a high-speed video of a metachronally coordinated row. Following the reconstruction, two numerical models were developed and simulated using an in-house immersed-boundary-method-based computational fluid dynamics solver. The two models included the original geometry (16 appendages in a row) and a sparse geometry (8 appendages, formed by removing every other appendage along the row). We found that appendage tip vortex interactions contribute to hydrodynamic performance via a vortex-weakening mechanism. Through this mechanism, appendage tip vortices are significantly weakened during the drag-producing recovery stroke. As a result, the swimming ctenophore produces less overall drag, and its thrust-to-power ratio is significantly improved (up to 55.0 % compared with the sparse model). Our parametric study indicated that such a propulsion enhancement mechanism is less effective at higher Reynolds numbers. Simulations were also used to investigate the effects of substrate curvature on the unsteady hydrodynamics. Our results illustrated that, compared with a flat substrate, arranging appendages on a curved substrate can boost the overall thrust generation by up to 29.5 %. These findings provide new insights into the fluid dynamic principles of propulsion enhancement underlying metachronal rowing. [ABSTRACT FROM AUTHOR]

The aim of this research was to use principal component analysis (PCA) to investigate the current pacing strategies of elite canoe kayak sprint athletes and to determine if there are differences in pacing patterns between medallists and non-medallists at major international competitions. Velocity data collected using global positioning systems (GPS) from all a-finals of major international competitions in 2016–2017 (including canoe and kayak, single and crew boat, and male and female) were downloaded from the International Canoe Federation's website. Data were normalised by the average velocity within each race and organised by race distance. In total 10, 14 and 16 races were analysed, and they followed all-out, positive, and 'seahorse-shaped' pacing strategies for the 200 m, 500 m, and 1000 m events, respectively. Normalised velocity PC1 (p = 0.039, ES = −0.44) and PC2 scores (p < 0.001, ES = −0.73) for 1000 m races were significantly different between medallists and non-medallists; however, significant differences between PCs were not found between groups in shorter race distances (i.e. 200 m and 500 m). Data collected using GPS provide information that can be used to better prepare athletes for canoe kayak sprint races lasting between 30 s and 240 s in duration. [ABSTRACT FROM AUTHOR]

Watts, SP, Binnie, MJ, Goods, PSR, Hewlett, J, Fahey-Gilmour, J, and Peeling, P. Demarcation of intensity from 3 to 5 zones aids in understanding physiological performance progression in highly trained under-23 rowing athletes. J Strength Cond Res 37(11): e593-e600, 2023--The purpose of this investigation was to compare 2 training intensity distribution models (3 and 5 zone) in 15 highly trained rowing athletes (n58 male; n57 female; 19.461.1 years) to determine the impact on primary (2,000-m single-scull race) and secondary (2,000-m ergometer time trial, peak oxygen consumption [V̇O2peak], lactate threshold 2 [LT2 power]) performance variables. Performance was assessed before and after 4 months training, which was monitored through a smart watch (Garmin Ltd, Olathe, KS) and chest-strap heart rate (HR) monitor (Wahoo Fitness, Atlanta, GA). Two training intensity distribution models were quantified and compared: a 3-zone model (Z1: between 50% V̇O2peak and lactate threshold 1 (LT1); Z2: between LT1 and 95% LT2; Z3: .95% LT2) and a 5-zone model (T1-T5), where Z1 and Z3 were split into 2 additional zones. There was significant improvement in LT2 power for both male (4.08% 6 1.83, p, 0.01) and female (3.52% 6 3.38, p 5 0.02) athletes, with male athletes also demonstrating significant improvement in 2,000-m ergometer time trial (2.3% 6 1.92, p 5 0.01). Changes in V̇O2peak significantly correlated with high-quality aerobic training (percent time in T2 zone; r5 0.602, p 50.02), whereas changes in LT2 power significantly correlated with "threshold" training (percent time in T4 zone; r50.529, p50.04). These correlations were not evident when examining intensity distribution through the 3-zone model. Accordingly, a 5-zone intensity model may aid in understanding the progression of secondary performance metrics in rowing athletes; however, primary (on-water) performance remains complex to quantify. [ABSTRACT FROM AUTHOR]

Optimisation of vision screening programmes can result the detection of refractive anomalies in a high proportion of school children. The Refractive Errors Among Children (REACH) programme aims to optimise outcomes of school-based vision screening in India by collaborating with hospitals and monitoring eye care throughout school attendance. REACH delivers school vision screening using pocket vision screeners (cards presenting rows of seven 0.2 logMAR Sloan letters at a 3 m viewing distance) in five states across India. Children who fail screening are referred for detailed evaluation including refraction, those requiring cycloplegic refraction are referred to partner hospitals. Spectacles are dispensed as needed and compliance is assessed. All data are recorded electronically. Out of 2,240,805 children aged 5 to 18 (mean 11.5; SD ±3.3) years, 2,024,053 have undergone REACH screening in 10,309 schools predominantly in rural locations (78.7%) and government-funded (76%). Of those screened, 174,706 (8.6%) underwent detailed evaluation. A higher proportion of children in private or urban schools (11.8% and 10.4% respectively) were referred for detailed evaluation than those in government-funded or rural schools (5.9% and 7.2%, respectively; p < 0.001). The proportion referred for detailed evaluation differed by state (p < 0.001), from 4.0% in West Bengal to 14.4% in Kerala. The REACH programme screened a high proportion of school children, providing further care and follow-up to optimise visual outcomes. [ABSTRACT FROM AUTHOR]

Aim: Aging decreases muscle mass and bone mineral density (BMD), especially in older women. It has been reported that rowing and inulin intake positively affect muscle and bone, respectively. We examined the synergistic effect of rowing and functional food intake, including inulin, on lean body mass, BMD, and physical function parameters in older Japanese women. Methods: Fifty women aged 65–79 years were divided into four groups with or without inulin intake and rowing. The interventions were carried out for 12 weeks in each group. We assessed lean body mass and BMD using dual‐energy X‐ray absorptiometry at baseline and after the intervention and examined the changes in the values in each group. Results: Lean body mass in all groups decreased, and the change in lean body mass in the group with rowing and inulin intake was significantly smaller than that in the group without them (−0.05 ± 0.61; −0.83 ± 0.59 kg; P = 0.030). The BMD in the three intervention groups increased after the 12‐week intervention. The change in BMD in each of the three intervention groups showed significant differences compared with the control group (Rowing + Inulin: P = 0.03; Rowing + No inulin: P = 0.01; No rowing + Inulin: P < 0.01). Conclusions: Rowing and the intake of functional foods, including inulin, synergistically prevented a decrease in lean body mass. These factors, individually and additively, might increase BMD in older Japanese women. Geriatr Gerontol Int 2023; 23: 779–787. [ABSTRACT FROM AUTHOR]

A super-resolution deep learning reconstruction (SR-DLR) algorithm trained using data acquired on the ultrahigh spatial resolution computed tomography (UHRCT) has the potential to provide better image quality of coronary arteries on the whole-heart, single-rotation cardiac coverage on a 320-detector row CT scanner. However, the advantages of SR-DLR at coronary computed tomography angiography (CCTA) have not been fully investigated. The present study aimed to compare the image quality of the coronary arteries and in-stent lumen between SR-DLR and model-based iterative reconstruction (MBIR). We prospectively enrolled 70 patients (median age, 69 years; interquartile range [IQR], 59–75 years; 50 men) who underwent CCTA using a 320-detector row CT scanner between January and August 2022. The image noise in the ascending aorta, left atrium, and septal wall of the ventricle was measured, and the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) in the proximal coronary arteries were calculated. Of the twenty stents, stent strut thickness and luminal diameter were quantitatively evaluated. The image noise on SR-DLR was significantly lower than that on MBIR (median 22.1 HU; IQR, 19.3–24.9 HU vs. 27.4 HU; IQR, 24.2–31.2 HU, p < 0.01), whereas the SNR (median 16.3; IQR, 11.8–21.8 vs. 13.7; IQR, 9.9–18.4, p = 0.01) and CNR (median 24.4; IQR, 15.5–30.2 vs. 19.2; IQR, 14.1–23.2, p < 0.01) on SR-DLR were significantly higher than that on MBIR. Stent struts were significantly thinner (median, 0.68 mm; IQR, 0.61–0.78 mm vs. 0.81 mm; IQR, 0.72–0.96 mm, p < 0.01) and in-stent lumens were significantly larger (median, 1.84 mm; IQR, 1.65–2.26 mm vs. 1.52 mm; IQR, 1.28–2.25 mm, p < 0.01) on SR-DLR than on MBIR. Although further large-scale studies using invasive coronary angiography as the reference standard, comparative studies with UHRCT, and studies in more challenging population for CCTA are needed, this study's initial experience with SR-DLR would improve the utility of CCTA in daily clinical practice due to the better image quality of the coronary arteries and in-stent lumen at CCTA compared with conventional MBIR. [ABSTRACT FROM AUTHOR]

The field harvesting process of harvesting machinery is often affected by high workload and environmental factors that can impede/delay manual rowing, thereby leading to lower efficiency and quality in the residual film collector. To address this challenge, an automatic rowing control system using the 4mz-220d self-propelled residual film collector as the experimental carrier was proposed in this study. Cotton stalks in the ridges were chosen as the research object, and a comprehensive application of key technologies, machinery, and electronic control was used, thereby incorporating a pure tracking model as the path-tracking control method. To achieve the automatic rowing function during the field traveling process, the fuzzy control principle was implemented to adjust the forward distance within the pure tracking model dynamically, and the expected steering angle of the steering wheel was determined based on the kinematic model of the recovery machine. The MATLAB/Simulink software was utilized to simulate and analyze the proposed model, thus achieving significant improvements in the automation level of the residual film collector. The field harvesting tests showed that the average deviation of the manual rowing was 0.144 m, while the average deviation of the automatic rowing was 0.066 m. Moreover, the average lateral deviation of the automatic rowing was reduced by 0.078 m with a probability of deviation within 0.1 m of 95.71%. The research study demonstrated that the designed automatic rowing system exhibited high stability and robustness, thereby meeting the requirements of the autonomous rowing operations of residual film collectors. The results of this study can serve as a reference for future research on autonomous navigation technology in agriculture. [ABSTRACT FROM AUTHOR]

The aim of our study is to analyse the physical characteristics and motor tests that can qualify rowers of different genders and nations. Young rowers from six nations (n = 190) were included in the study. After the anthropometric measurements, the average power (W100m) and maximum power (W5 strokes) were examined with start tests on a rowing ergometer. The estimated relative aerobic capacity (ErVO2max) was calculated, and the standing triple jump test (STJ) was also measured. The relationship of the individual variables to performance was also investigated. Analysing the start tests, the results of the boy group were significantly larger than those of the girl group (p < .05). The correlation between STJ and W5 strokes and W100m is significant in the boy group and also in the girl group. The correlation between body weight (BW) and performance is stronger in both groups. In our study, the differences between the sexes are clear, considering all groups, we can observe the tendency that the increasing value of STJ means also increasing of maximum (W5 strokes) and average power (W100m), and we found a relationship between anthropometrical characteristics and performance already in adolescence. It seems clear that in order to achieve a high level of rowing performance, in addition to developing endurance, attention should also be paid to the development of power (especially dynamic leg power) in the program of rowers. [ABSTRACT FROM AUTHOR]

Heroes on the Water is a nonprofit organization providing kayak fishing programs to veterans and their families. The purpose of this study was to explore the impact kayak fishing programs, provided by Heroes on the Water, had on posttraumatic growth in military veterans in the United States. The concept of posttraumatic growth suggests that individuals may experience positive psychological changes after severe traumatic events. Research suggests posttraumatic growth can occur in the form of recognizing personal strengths, new possibilities, relating to others, an appreciation for life, and spiritual changes. Studies also suggest that recreation can aid in facilitation of growth. Additionally, recreation has been considered a complementary form of treatment for veterans, specifically the use of nature-based and outdoor recreation programs. For this study, participants reflected on their experiences before and after engaging in Heroes on the Water using the Posttraumatic Growth Inventory. Though the results cannot be generalized, participants reported an increase in score after participating in Heroes on the Water kayak fishing programs. This study adds to the knowledge about the use of recreation to facilitate growth in veterans and encourages continued research on this topic. [ABSTRACT FROM AUTHOR]

In this longitudinal interpretative case study, researchers examined the beliefs and practices related to democratic citizenship and critical multiculturalism of five beginning social studies teachers from their teacher preparation through their fourth year in the classroom. Using Banks's typology of citizenship as a theoretical framework, they found that all five teachers' beliefs remained relatively consistent. However, there was a clear division between teachers who believed citizenship was primarily about civic participation and those who believed it was primarily about social transformation. Moreover, they found that a complex interplay between the teachers' beliefs and their school contexts presented numerous barriers to regularly implementing classroom-based multicultural democratic education in practice. [ABSTRACT FROM AUTHOR]

Traditionally, vernacular Nordic clinker boats are built without plans or templates. The local boat traditions all have a system of design that was handed over from master to apprentice. In some local traditions, a simple plumb level was used to guide the boatbuilder. The plumb level was placed on the planks of the hull during the build to give them the right angles of inclination in certain parts of the hull. Knowledge of how to use this plumb level is still considered part of living, unbroken traditions in some areas. In some local traditions, however, there are no longer any living tradition bearers that have the knowledge of how this tool was used in the local context. In this contribution, I will discuss how this lost knowledge can be reconstructed using old artefacts as a source material. I am investigating the tradition of building vernacular, clinker-built boats called 'öka' for sailing and rowing. This specific boat building tradition was located in the 19th century Stockholm archipelago. The artefacts in this case are preserved boats built in the old tradition and preserved plumb levels from closely related traditions. A central question in this context is to locate the exact positions in the boat that were measured by the plumb level. Working with reverse engineering, the measuring can be performed on preserved boats, but the right places for measuring still must be located to reconstruct the knowledge of how and where to use the tool. Some preserved plumb levels have markings that can be used in this investigation to match the locations and angles in the preserved boats. In this contribution, I will also discuss the possibility of applying the traditional measuring methods used by the old boatbuilders in today's surveys and reconstructions, not translating the craft object into a digital 3D model or a lines plan. [ABSTRACT FROM AUTHOR]

The organized sport of rowing is a historied and traditioned sport with a broad range of competitive levels from recreational and competitive clubs to high school and collegiate programs as [...], Participation on any level of the sport of rowing provides rowers with physical, psychological, and social benefits. The unique demands of the sport allow it to be accessible for athletes who are Deaf or hard of hearing (D/HOH). Inclusive participation in rowing allows rowers who are D/HOH to experience similar benefits to their teammates who hear. However, to achieve an inclusive team environment, coaches, coxswains, and teammates need to understand and accommodate the communication needs of rowers who are D/HOH. Many of these accommodations stem from collaborating on the timing and medium of feedback and instruction, how best to utilize an interpreter, and the creation of one-handed signals to be used on the water. The purpose of this article is to outline the needs of rowers who are D/HOH, the benefits of promoting accessibility and inclusion for these athletes, and provide recommendations and strategies for coaches, coxswains, and teammates to facilitate that accessibility and inclusion in and out of the boat. Keywords: Inclusion, feedback, sign language, coxswain, coach

This study aimed to investigate the changes in surface electromyography (EMG) in four anatomical segments of three muscles during a 2000 m rowing ergometer test. 19 healthy male rowers were requested to perform the test. Surface electrodes were attached to their vast medialis (VAM), erector spinae (ERS) and latissimus dorsi (LD) muscles. Raw EMG signals were presented at five different distance points: start (D0), 500 m (D1), 1000 m (D2), 1500 m (D3) and 2000 m (D4). The mean velocity and power were greater during 0–500 m and 1500–2000 m phases compared to 500–1000 m and 1000–1500 m phases (p < 0.01). Integrated Electromyography (iEMG) of VAM was significantly higher at the start and 2000 m compared to consecutive points (p < 0.05). The peak root mean square (pRMS) of ERS muscles was significantly higher at the start and 2000 m (p < 0.05). The frequency domain indexes mean frequency (MNF) and median frequency (MDF) of all muscles were significantly reduced at 1500 m compared to 1000 m (p < 0.05). However, no significant changes were observed in time domain indexes of LD muscles at any distance points (p > 0.05). A “fast start-speed maintains-final sprint” pacing pattern was observed during the 2000 m all-out rowing ergometer test. The EMG activation rates of VAM and ERS muscles were greater at the start and final phases, contributing to the increase in power. The decline in MNF and MDF of all three muscles at 1500 m could be related to greater muscle fatigue at this point. When using EMG to analyze endurance exercise, the results were dependent on the length of the test. Although not all EMG indexes were sensitive enough to detect these changes, combing them with different indicators for a comprehensive analysis might be considered.

Investigating the relationship between the movement patterns of multiple limb segments during the rowing stroke on the resulting force production in elite rowers can provide foundational insight into optimal technique. It can also highlight potential mechanisms of injury and performance improvement. The purpose of this study was to conduct a kinematic analysis of the rowing stroke together with force production during a step test in elite national-team heavyweight men to evaluate the fundamental patterns that contribute to expert performance. Twelve elite heavyweight male rowers performed a step test on a row-perfect sliding ergometer [5 × 1 min with 1 min rest at set stroke rates (20, 24, 28, 32, 36)]. Joint angle displacement and velocity of the hip, knee and elbow were measured with electrogoniometers, and force was measured with a tension/compression force transducer in line with the handle. To explore interactions between kinematic patterns and stroke performance variables, joint angular velocities of the hip, knee and elbow were entered into principal component analysis (PCA) and separate ANCOVAs were run for each performance variable (peak force, impulse, split time) with dependent variables, and the kinematic loading scores (Kpc,ls) as covariates with athlete/stroke rate as fixed factors. The results suggested that rowers’ kinematic patterns respond differently across varying stroke rates. The first seven PCs accounted for 79.5% (PC1 [26.4%], PC2 [14.6%], PC3 [11.3%], PC4 [8.4%], PC5 [7.5%], PC6 [6.5%], PC7 [4.8%]) of the variances in the signal. The PCs contributing significantly (p ≤ 0.05) to performance metrics based on PC loading scores from an ANCOVA were (PC1, PC2, PC6) for split time, (PC3, PC4, PC5, PC6) for impulse, and (PC1, PC6, PC7) for peak force. The significant PCs for each performance measure were used to reconstruct the kinematic patterns for split time, impulse and peak force separately. Overall, PCA was able to differentiate between rowers and stroke rates, and revealed features of the rowing-stroke technique correlated with measures of performance that may highlight meaningful technique-optimization strategies. PCA could be used to provide insight into differences in kinematic strategies that could result in suboptimal performance, potential asymmetries or to determine how well a desired technique change has been accomplished by group and/or individual athletes.

In cognitive–motor dual-task situations, the extent of performance decrements is influenced by the attentional requirements of each task. Well-learned motor skills should be automatized, leading to less interference. This study presents two studies combining an episodic memory encoding task with well-practiced motor tasks in athletes. Study 1 asked 40 rowers (early teenagers to middle adulthood) to row on ergometers at slow or fast speeds. In study 2, Taekwondo athletes (n = 37) of different skill levels performed a well-practiced sequence of martial arts movements. Performing the motor task during encoding led to pronounced performance reductions in memory in both studies, with costs of up to 80%. Cognitive costs were even larger when rowing with the fast compared to the slow speed in study 1. Both studies also revealed decrements in motor performances under dual-task conditions: Rowing became slower and more irregular (study 1), and the quality of the Taekwondo performance was reduced. Although higher-level athletes outperformed others in motor skills under single-task conditions, proportional dual-task costs were similar across skill levels for most domains. This indicates that even well-practiced motor tasks require cognitive resources.

Adult elite rowers are at risk of developing low back pain (LBP). However, LBP data on adolescent elite rowers is currently insufficient. Therefore, the aim of this study was to assess LBP prevalence, LBP intensity and training characteristics in male adolescent elite rowers and a healthy control group. Twenty rowers (mean age 15.8 ± 1.2 years) and a non-athletic control group matched by age and gender (n = 13) were prospectively enrolled and underwent LBP assessment with a validated questionnaire and magnetic resonance imaging (MRI) of the lumbar spine muscles, which included a T2-mapping sequence. From the quantitative image data, T2 relaxation times were calculated. The prevalence of LBP in the last 24 hours and 3 months in the rowing group was 55.0% and 85.0%, respectively, compared to 23.1% and 30.8% in the control group (p < 0.001). Rowers had significantly longer T2 relaxation times of the paraspinal muscles compared to controls (p ≤ 0.041). LBP intensity was associated with longer T2 relaxation times (p < 0.001). Adolescent rowers had a higher prevalence of LBP compared to an age-matched control group. The observed increase in T2 relaxation might be explained by muscle soreness due to strenuous exercise, which is correlated with short-term pain intensity. [ABSTRACT FROM AUTHOR]

In the face of increasing concerns around privacy and security in the use of unmanned aerial vehicles (UAVs) for mobile edge computing (MEC), this study proposes a novel approach to secure UAV-assisted federated learning. This research integrates a trusted execution environment (TEE) into UAV-assisted federated learning and proposes a robust aggregation algorithm based on cosine distance, denoted as CosAvg. This study further designs and evaluates a TEE-based federated learning model, comparing its resource overhead with other secure aggregation frameworks, like homomorphic encryption (HE) and differential privacy (DP). Experimental results indicate a significant reduction in resource overhead for TEE against DP and HE. Moreover, the proposed CosAvg algorithm demonstrated superior robustness against adversarial scenarios, maintaining high accuracy in the presence of malicious clients. The integration of TEE and the CosAvg algorithm provides a secure and robust solution for UAV-assisted federated learning, effectively defending both gradient inversion attacks and byzantine attacks. [ABSTRACT FROM AUTHOR]

The purpose of this study was to assess the effects of stroke rate and sex on trunk and shoulder kinematics of Olympic athletes during rowing on an ergometer. Fifty-eight participants (31 females and 27 males) from the Chinese National Rowing Team were recruited. Trunk (i.e., the pelvis, lumbar and thoracic spine) and shoulder kinematics were measured using an inertial measurement unit system for three stroke rates (18, 26, and 32 strokes/min). Range of motion and angles at the catch and finish were assessed using mixed model ANOVA and correlation analyses with rowing power. Range of motion increased significantly at higher rates for both female and male athletes. This may be a strategy used by athletes when dealing with higher demand for power during training, because a greater range of motion with a longer stroke length could reduce the demand for force generation and possibly delay fatigue. Female rowers exhibited greater range of motion in the lumbar spine, thorax and shoulders than males due to more extended positions at the finish. The sex-related kinematic differences may be attributed to differences in body size, muscle strength and endurance. Practitioners are recommended to consider these factors when developing rowing techniques and providing training suggestions. [ABSTRACT FROM AUTHOR]

A rowing cycle is characterised by a stretch-shortening cycle (SSC) at the quadriceps femoris muscle-tendon unit (MTU) level. However, due to the associated decoupling between MTU and muscle fascicle length changes, it remains unclear whether a rowing cycle causes active stretch at the muscle level. Fifteen young, sub-elite, male rowers (19.5 ± 1.6 yr; 1.94 ± 0.06 m; 91.9 ± 5.4 kg; rowing experience: 7.5 ± 2.8 yr) performed randomised 60-s rowing intervals using a traditional style at a low (LiR) and high intensity (HiR) and a micro-pause style at a low intensity (MpR). Muscle activity, knee joint angles, and muscle fascicle length changes from the left-sided vastus lateralis (VL) muscle were quantified using surface electromyography, inertial measurement units, and B-mode ultrasound imaging, respectively. All rowing conditions showed active fascicle stretch during late knee flexion (p≤0.001, standardised mean difference (SMD) ≥0.72) and subsequent active fascicle shortening throughout knee extension. Active fascicle stretch duration, amplitude and velocity (rANOVA: p≤0.001, ηp2 = 0.49) were not significantly different (p≥0.174; SMD≤0.26) between LiR and MpR, but were significantly increased during HiR (p≤0.001; SMD≥0.70). The percentage of rowing cycles that involved active fascicle stretch (rANOVA: p≤0.001, ηp2 = 0.95; post-hoc: p≤0.001, SMD≥0.87) was also significantly higher for HiR (98.3 ±12.9%) compared with both LiR (65.0 ± 48.1%) and MpR (68.3 ± 46.9%). In conclusion, rowing involves SSC at the VL muscle fascicle level, but the amount of active stretch differs between rowing intensities, with the longest, largest, and fastest active stretch occurring during HiR. SSC-based mechanisms may therefore contribute more to rowing performance during HiR than LiR or MpR. Highlights Surface electromyography and ultrasound imaging revealed stretch-shortening cycles (SSCs) of the vastus lateralis muscle fascicles during rowing Increased active fascicle stretch duration, amplitude and velocity from low- to high-intensity rowing indicate that SSC-based mechanisms likely contribute more to performance during high-intensity rowing The SSC within the vastus lateralis muscle was independent of the rowing style at the same low rowing intensity [ABSTRACT FROM AUTHOR]