Search Results (13)

Background: Exercise-induced bronchoconstriction (EIB) is common in athletes, being more frequent in outdoor endurance-based/long-distance sports. We followed a World-Class marathon paddler’s season with recurrent episodes of EIB, which intensified during cold exposure workouts. This unique immunophenotype profile during the season and its variations were reflected in acute and chronic inflammatory markers. Methods: A longitudinal case study was conducted with blood sampling obtained from a single paddler after overnight fasting at three timepoints: T1 (beginning of season, after 15-day rest period), T2 (post-Winter National Championship), and T3 (post-Summer National Championship). Complete blood counts and lymphocyte immunophenotyping were performed using automated hematology analysis and multiparametric flow cytometry. Results: The total numbers of leukocytes (T1: 6.3; T2: 5.0; T3: 5.5 × 10⁹/L), neutrophils (3.1; 2.5; 2.8 × 10⁹/L), and lymphocytes (2.4; 1.8; 2.2 × 10⁹/L) declined between T1 and T2, followed by a partial recovery at T3. In contrast, monocyte counts exhibited the reverse pattern (0.41; 0.62; 0.31 × 10⁹/L). The two T cell subsets (αβ and γδ) remained relatively stable, showing only minor seasonal fluctuations. CD19+ B cells, initially at very low levels, increased steadily as the season progressed (0.05; 0.07; 0.16 × 10⁹/L). During T2, the proportion of memory lymphocytes (CD45RO+) rose, while naive cells (CD45RA+) declined; this trend was subsequently inverted at M3. Although the CD4+/CD8+ ratio varied over time, it consistently stayed below the normal reference range established for healthy controls (0.50; 0.83; 0.60 for T1, T2, and T3, respectively). Conclusions: The immune assessment of the World-Class marathon paddler revealed transient immunosuppression early in the season, marked by reduced neutrophils, a low CD4+/CD8+ ratio, and diminished CD19+ lymphocytes. Over time, immune parameters showed signs of recovery, indicating a temporary imbalance that did not impair the athlete’s physical performance. Conclusions: This case study of an elite marathon kayaker revealed transient immune fluctuations across a competitive season, including early immunosuppression (low neutrophils, CD4+/CD8+ ratio 0.50, and minimal CD19+ B cells) followed by partial recovery mid- and late-season. Despite persistently inverted CD4+/CD8+ ratios suggesting chronic immune dysregulation, the athlete maintained competitive performance, highlighting the temporary nature of these changes and emphasizing that regular immune monitoring can help optimize health and performance in elite athletes. Full article

Paddler athletes use resistance training (RT) to optimize power output (PO) during competitions. Understanding the power–load relationship (P–Lr) is essential for effective RT prescription. Moreover, the push-to-pull ratio (PU/PR)—the one-repetition maximum (1RM) of a pulling exercise divided by the one of a pushing exercise—has been suggested as a metric associated with sprint kayak performance. This study aimed to describe P–Lr in three guided exercises (bench press (BP), ballistic bench press (BBP), and prone bench pull (PBP)), along with PU/PR in international-level canoeing and kayaking athletes. Nine male athletes (21.0 ± 1.5 years) were monitored during two sessions of an incremental testing protocol. Load ranged from 30 to 100 kg in BP, 30 to 95 kg in PBP, and 20 to 60 kg in BBP. Instantaneous displacement was measured using a linear position transducer, and PO was computed for each repetition and exercise. PU/PR was calculated upon PBP and BP. A two-way repeated-measures ANOVA was used to explore differences among exercises and relative load from 20% to 90% 1RM. PBP displayed a higher PO between 40% and 90% 1RM compared to BP and BBP), while no statistical difference was found between BP and BBP at any relative load. Additionally, mean PU/PR resulted 0.96. This study provides preliminary values regarding P–Lr and PU/PR in elite paddlers, which may assist in designing training programs for those targeting major competitions. Full article

Elite kayakers are characterized by robust somatotypes and a high degree of technical skills acquired from early ages along the biological maturity process. This study aimed to analyze the interdependence of anthropometric attributes, maturity status, and new stroke kinematics variables such as long- and short-term stroke steadiness in young sprint paddlers. Twenty-two elite young male canoeists, aged 13.5 ± 0.4 years, volunteered for the investigation. A battery of anthropometric measurements was obtained for each individual while stroke kinematics were determined by lateral recordings in an all-out 200 m test. Frame-to-frame analysis of consecutive strokes allowed the determination of short-term and long-term steadiness. Significant and positive correlations (p < 0.05) between maturity status, canoeing experience, and stroke steadiness were identified, especially in long-term steadiness (r = 0.60–0.83). In addition, upper-body dimensions in the chest and arms exhibited strong associations with both short- and long-term steadiness (p < 0.05). These findings suggest that biological maturity, but particularly experience, are key factors for a higher stroke efficiency. Therefore, early identification of morphological characteristics and maturity status along with specific practice in canoeing should be taken into consideration for ideal talent development in young canoeists. Full article

Purpose: This study aimed to detect differences in post-exercise brain activity between the left and right paddlers due to exercise by analyzing the resting-state electroencephalogram (EEG) power spectrum before and after exercise. Methods: Twenty-one right paddlers and twenty-two left paddlers completed a 1 km all-out test on a dragon boat ergometer, and their heart rate and exercise time were recorded. EEG signals were collected from superficial brain layers before and after exercise; then, the EEG power spectrum was extracted and compared in different frequency bands. In addition, the degree of lateralization in each brain region was assessed by the asymmetry index. Results: There was no significant difference in the power spectrum values and asymmetry indices between the left and right paddlers before rowing (p ˃ 0.05). However, after rowing, the left-paddlers group had significantly higher spectral power values in θ and α bands than the right-paddlers group (p < 0.05), and brain lateralization in both groups of athletes occurred mainly in the ipsilateral hemisphere of the frontal and central regions. Conclusion: The 1 km of rowing induced more brain activation in the left paddlers, and both left and right paddlers showed functional aggregation of hemispheric lateralization. Full article

The purpose of this work was to describe the leg-muscle-generated push force characteristics in sprint kayak paddlers for females and males on water. Additionally, the relationship between leg pushing force characteristics and velocity was investigated. Twenty-eight paddlers participated in the study. The participants had five minutes of self-chosen warm-up and were asked to paddle at three different velocities, including maximal effort. Left- and right-side leg extension force were collected together with velocity. Linear regression analyses were performed with leg extension force characteristics as independent variables and velocity as the dependent variable. A second linear regression analysis investigated the effect of paddling velocity on different leg extension force characteristics with an explanatory model. The results showed that the leg pushing force elicits a sinus-like pattern, increasing and decreasing throughout the stroke cycle. Impulse over 10 s showed the highest correlation to maximum velocity (r = 0.827, p < 0.01), while a strong co-correlation was observed between the impulse per stroke cycle and mean force (r = 0.910, p < 0.01). The explanatory model results revealed that an increase in paddling velocity is, among other factors, driven by increased leg force. Maximal velocity could predict 68% of the paddlers’ velocity within 1 km/h with peak leg force, impulse over 10 s, and stroke rate (p-value < 0.001, adjusted R-squared = 0.8). Sprint kayak paddlers elicit a strong positive relationship between leg pushing forces and velocity. The results confirm that sprint kayakers’ cyclic leg movement is a key part of the kayaking technique. Full article

Previous canoe sprint studies evaluated the best paddlers of their categories. This investigation aimed to identify the importance of biological maturation and athletes’ experience in kayaking performance and observe possible differences regarding anthropometry, years of practice, and performance. Eighty under 14 years of age (U14) and fifty under 16 years of age (U16) kayakers aged 13.40 ± 0.54 and 15.25 ± 0.61 years were evaluated. Kayakers were assessed for anthropometry (body mass (kg); stretch stature (cm); and sitting height (cm)), performance (time at 3000 m for U14 and 5000 m for U16 kayakers), and somatic maturation (predicted adult height (PAH) and maturity offset). In the U14 kayakers, years of practice, sitting height, and maturity offset showed significant differences (p < 0.05) between the Top10 and Middle, and Middle and Bottom10 performance times. Significantly higher (p < 0.05) sitting heights were identified between the Top10 and Middle U16 kayakers. Significant differences (p < 0.05) were observed for maturity offset and PAH% between the Top10 and Middle groups compared to the Bottom10 group. In conclusion, this research shows differences in the maturity status of young U14 and U16 kayakers, identifying that the more biologically mature individuals, with more years of specific practice, achieved better performances. Full article

Stand-up paddleboarding (SUP) is an increasingly popular sport but, as in other sports, there is an injury ratio associated with practicing it. In other types of sport, some factors have been linked to the likelihood of suffering an injury, among which stretching, core training and resistance training may be considered the most significant. Therefore, the main aim of this study was to identify the training factors that could influence injuries suffered by participants in international SUP competitions. Ninety-seven questionnaires were collected from paddlers who participated in an international SUP circuit, with epidemiological data being gathered about injuries and different questions related to the training undertaken. A multi-factor ANOVA test was used to identify the factors which influence the state of injury. Results showed that almost 60% of injuries occurred in the arms or in the upper thoracic region, around 65% of which were in tendons or muscles and, in almost half of cases, were related to overuse. Likewise, the results showed that athletes with injury performed fewer resistance training sessions per week (p = 0.028), over fewer months per year (p = 0.001), more weekly training sessions (p = 0.004) and, lastly, a greater volume of weekly training (p = 0.003) than athletes without injury. Moreover, the most important training factors that reduce the likelihood of suffering an injury were taken into account-in. particular, resistance training alone (p = 0.011) or together with CORE training (p = 0.006) or stretching (p = 0.012), and the dominant side of paddling (p = 0.032). In conclusion, resistance training would seem to reduce the likelihood of injury among SUP practitioners, and such benefits could be obtained by resistance training alone or in combination with CORE training or stretching. Full article

A paddler’s characteristics can condition the placement of the elements of the boat. The aim of this study was to analyze the differences among kayakers from different skill levels on their sagittal spine position, hamstring extensibility and anthropometric variables; and to determine which variables could be used to determine the arrangement of the elements in the kayak. Thirty-four male sprint kayakers (8 Olympic-level, 13 from the U-23 national team and 13 amateurs) participated in this study. Anthropometric variables, following the protocol of the International Society for the Advancement of Kinanthropometry (ISAK); hamstring extensibility, with active and passive straight leg raise test; sagittal spine position in standing position and in the kayak, and the arrangement of the elements of the boat were measured. The groups with a high skill level showed a lower pelvic tilt in attack position in the kayak than amateurs (p ≤ 0.001). The U-23 group had a lower hamstring extensibility than amateurs (p = 0.053–0.013). The distance from the footrest to the different parts of the seat were dependent on the iliospinale measurement (R = 0.896–0.912). In conclusion, there were differences among groups on the sagittal spine position and hamstring extensibility. In addition, the placement of the boat elements was dependent on anthropometric variables, but not on hamstring extensibility or sagittal spine position. Full article

This study used instrumented paddles to obtain on-water kinetic variables of two-seater (K2) crews during sprint kayaking. A total of 74 male kayakers of various ability levels (national team: 9, recreational club: 38, school team: 27) comprising 39 K2 crews were recruited. Both the front and back paddlers were provided with an instrumented paddle to perform 200-m maximal effort paddling in a reservoir. Force, power, and temporal variables were extracted from the paddle data. Difference among groups were compared using a factorial Analysis of Variance. Results showed that the force, power, and temporal characteristics of the front and back paddlers were similar during maximal effort sprint kayaking. Proficient kayakers produced greater kinetic outputs than less proficient kayakers, while the coordination strategy based on timing differences at key events between the two crew members in a K2 boat was similar across ability levels. These data can be useful for coaches, sport scientists, and athletes in planning and monitoring the training. Full article

Background: Due to the importance of energy efficiency and economy in endurance performance, it is important to know the influence of different paddling cadences on these variables in the stand-up paddleboarding (SUP). The purpose of this study was to determine the effect of paddling at different cadences on the energy efficiency, economy, and physiological variables of international SUP race competitors. Methods: Ten male paddlers (age 28.8 ± 11.0 years; height 175.4 ± 5.1 m; body mass 74.2 ± 9.4 kg) participating in international tests carried out two test sessions. In the first one, an incremental exercise test was conducted to assess maximal oxygen uptake and peak power output (PPO). On the second day, they underwent 3 trials of 8 min each at 75% of PPO reached in the first test session. Three cadences were carried out in different trials randomly assigned between 45–55 and 65 strokes-min⁻¹ (spm). Heart rate (HR), blood lactate, perceived sense of exertion (RPE), gross efficiency, economy, and oxygen uptake (VO₂) were measured in the middle (4-min) and the end (8-min) of each trial. Results: Economy (45.3 ± 5.7 KJ·l⁻¹ at 45 spm vs. 38.1 ± 5.3 KJ·l⁻¹ at 65 spm; p = 0.010) and gross efficiency (13.4 ± 2.3% at 45 spm vs. 11.0 ± 1.6% at 65 spm; p = 0.012) was higher during de 45 spm condition than 65 spm in the 8-min. Respiratory exchange ratio (RER) presented a lower value at 4-min than at 8-min in 55 spm (4-min, 0.950 ± 0.065 vs. 8-min, 0.964 ± 0.053) and 65 spm cadences (4-min, 0.951 ± 0.030 vs. 8-min, 0.992 ± 0.047; p < 0.05). VO₂, HR, lactate, and RPE were lower (p < 0.05) at 45 spm (VO₂, 34.4 ± 6.0 mL·kg⁻¹·min⁻¹; HR, 161.2 ± 16.4 beats·min⁻¹; lactate, 3.5 ± 1.0 mmol·l⁻¹; RPE, 6.0 ± 2.1) than at 55 spm (VO₂, 38.6 ± 5.2 mL·kg⁻¹·min⁻¹; HR, 168.1 ± 15.1 beats·min⁻¹; lactate, 4.2 ± 1.2 mmol·l⁻¹; RPE, 6.9 ± 1.4) and 65 spm (VO₂, 38.7 ± 5.9 mL·kg⁻¹·min⁻¹; HR, 170.7 ± 13.0 beats·min⁻¹; 5.3 ± 1.8 mmol·l⁻¹; RPE, 7.6 ± 1.4) at 8-min. Moreover, lactate and RPE at 65 spm was greater than 55 spm (p < 0.05) at 8-min. Conclusion: International male SUP paddlers were most efficient and economical when paddling at 45 spm vs. 55 or 65 spm, confirmed by lower RPE values, which may likely translate to faster paddling speed and greater endurance. Full article

The full comprehension of the impact with which each force is involved in kayak propulsion is very difficult. The measure of the force on the paddle or the stroke rate only is often not enough for the coach to identify the best actions useful to improve the performances of a kayaker. To this purpose, the synchronous measurement of all parameters involved in the kayak propulsion, both dynamic (force acting on paddle and foot brace) and kinematic (stroke frequency, displacement, velocity, acceleration, roll, yaw, and pitch of the boat) could suggest to the coach more appropriate strategies for better understanding of the paddler’s motion and the relevant effects on the kayak behavior. Some simulation models, as well as measurement systems of increasing complexity, have been proposed in the recent years. In this paper, we present the e-Kayak system: A multichannel Digital Acquisition (DAQ) system specifically customized for flatwater kayaking. The system will be described in depth and its capability investigated through specific measurement results. Full article

Background: This study aimed to understand individual muscle use in different paddling postures in stand-up paddle boarding (SUP). Methods: Sixteen college students were recruited in this study. Surface electromyography of 16 muscles on the dominant side was recorded. Results: In the time series, the biceps muscle exhibited a continuous activation pattern in the pull phase when kneeling, whereas when standing, the muscle contracted considerably in the exit and recovery phases, implying that it plays different roles in the two postures. The biceps also exhibited significantly higher muscle activation in the kneeling position than it did in the standing position. The maximum muscle activity levels of the external oblique abdominis and triceps were significantly higher when standing than when kneeling. In addition, an unstable SUP board activated the gastrocnemius to help paddlers maintain stability on a swaying surface. Moreover, additional power from the wrist flexor must be used in the recovery and catch phases to stabilize paddle control in the standing position. Conclusion: The knowledge that changes in SUP posture activate different muscle groups can enhance training efficiency and provide a reference for designing individualized training programs. Full article

Nowadays, in modern elite sport, the identification of the best training strategies which are useful in obtaining improvements during competitions requires an accurate measure of the physiologic and biomechanical parameters that affect performance. The goal of this pilot study was to investigate the capabilities of the e-Kayak system, a multichannel digital acquisition system specifically tailored for flatwater sprint kayaking application. e-Kayak allows the synchronous measure of all the parameters involved in kayak propulsion, both dynamic (including forces acting on the paddle and footrest) and kinematic (including stroke frequency, displacement, velocity, acceleration, roll, yaw, and pitch of the boat). After a detailed description of the system, we investigate its capability in supporting coaches to evaluate the performance of elite athletes’ trough-specific measurements. This approach allows for a better understanding of the paddler’s motion and the relevant effects on kayak behavior. The system allows the coach to carry out a wide study of kayak propulsion highlighting, and, at the same time, the occurrences of specific technical flaws in the paddling technique. In order to evaluate the correctness of the measurement results acquired in this pilot study, these results were compared with others which are available in the literature and which were obtained from subjects with similar characteristics. Full article