Leonardo Henrique Dalcheco Messias

Physiological, psychological and biomechanical parameters applied in canoe slalom training: a review

Canoe slalom is an Olympic sport held in natural and artificial rivers, with peculiar characteristics as compared to other sports. This sport is divided into the subdisciplines of kayak single (K1), canoe single (C1) and canoe double (C2), which also have specific characteristics. As with many other Olympic sports still on the rise, which lack expressive media recognition, few scientific studies have investigated canoe slalom. This information gap minimises possible similarities between theory and practice and advances in the preparation of teams (i.e., coaches, physical trainers and athletes). It is well established that for athletic development, several areas of knowledge must be integrated and applied to the specific nature of the sport, optimising sports training and athletic performance. Accordingly, this review aims to bring together studies on the physiological, psychological and biomechanical parameters, sports strategies and periodisation training applied to canoe slalom, explaining the need for increased knowledge in each of these areas of the practice of this sport.

All-out Test in Tethered Canoe System can Determine Anaerobic Parameters of Elite Kayakers.

The aims of this study were to use a specific all-out 30-sec tethered test to determine the anaerobic parameters in elite kayakers and verify the relationship between these results and sports performance. Twelve elite slalom kayakers were evaluated. The tethered canoe system was created and used for the all-out 30-sec test application. Measurements of peak force, mean force, minimum force, fatigue index and impulse were performed. Performance evaluation was determined by measuring the time of race in a simulated race containing 24 gates on a white-water course. Blood was collected (25-µl) for analysis of lactate concentration at rest and at 2, 4, 6, 8 and 10-min intervals after both the all-out test and the simulated race. The Pearson product moment correlation shows a inverse and significant relationship of peak force, mean force and impulse with time of race. Blood lactate concentrations after the all-out test and the simulated race peak at same time (4 min). Additionally, no interaction was visualized between time and all-out test/simulated race for blood lactate concentrations (P <0.365). These results suggest a relationship between the parameters of the all-out test and performance. Thus, the tethered canoe system is a useful tool for determining parameters that could be used in training control of slalom kayakers.

The Lactate Minimum Test: Concept, Methodological Aspects and Insights for Future Investigations in Human and Animal Models

In 1993, Uwe Tegtbur proposed a useful physiological protocol named the lactate minimum test (LMT). This test consists of three distinct phases. Firstly, subjects must perform high intensity efforts to induce hyperlactatemia (phase 1). Subsequently, 8 min of recovery are allowed for transposition of lactate from myocytes (for instance) to the bloodstream (phase 2). Right after the recovery, subjects are submitted to an incremental test until exhaustion (phase 3). The blood lactate concentration is expected to fall during the first stages of the incremental test and as the intensity increases in subsequent stages, to rise again forming a “U” shaped blood lactate kinetic. The minimum point of this curve, named the lactate minimum intensity (LMI), provides an estimation of the intensity that represents the balance between the appearance and clearance of arterial blood lactate, known as the maximal lactate steady state intensity (iMLSS). Furthermore, in addition to the iMLSS estimation, studies have also determined anaerobic parameters (e.g., peak, mean, and minimum force/power) during phase 1 and also the maximum oxygen consumption in phase 3; therefore, the LMT is considered a robust physiological protocol. Although, encouraging reports have been published in both human and animal models, there are still some controversies regarding three main factors: (1) the influence of methodological aspects on the LMT parameters; (2) LMT effectiveness for monitoring training effects; and (3) the LMI as a valid iMLSS estimator. Therefore, the aim of this review is to provide a balanced discussion between scientific evidence of the aforementioned issues, and insights for future investigations are suggested. In summary, further analyses is necessary to determine whether these factors are worthy, since the LMT is relevant in several contexts of health sciences.

Advances of the reverse lactate threshold test: Non-invasive proposal based on heart rate and effect of previous cycling experience

Our first aim was to compare the anaerobic threshold (AnT) determined by the incremental protocol with the reverse lactate threshold test (RLT), investigating the previous cycling experience effect. Secondarily, an alternative RLT application based on heart rate was proposed. Two groups (12 per group-according to cycling experience) were evaluated on cycle ergometer. The incremental protocol started at 25 W with increments of 25 W at each 3 minutes, and the AnT was calculated by bissegmentation, onset of blood lactate concentration and maximal deviation methods. The RLT was applied in two phases: a) lactate priming segment; and b) reverse segment; the AnT (AnTRLT) was calculated based on a second order polynomial function. The AnT from the RLT was calculated based on the heart rate (AnTRLT-HR) by the second order polynomial function. In regard of the Study 1, most of statistical procedures converged for similarity between the AnT determined from the bissegmentation method and AnTRLT. For 83% of non-experienced and 75% of experienced subjects the bias was 4% and 2%, respectively. In Study 2, no difference was found between the AnTRLT and AnTRLT-HR. For 83% of non-experienced and 91% of experienced subjects, the bias between AnTRLT and AnTRLT-HR was similar (i.e. 6%). In summary, the AnT determined by the incremental protocol and RLT are consistent. The AnT can be determined during the RLT via heart rate, improving its applicability. However, future studies are required to improve the agreement between variables.

Aerobic and Anaerobic Swimming Force Evaluation in One Single Test Session for Young Swimmers

This study aims to propose and validate the tethered swimming lactate minimum test (TSLacmin) estimating aerobic and anaerobic capacity in one single test session, using force as measurement parameter. 6 male and 6 female young swimmers (age=15.7±1.1 years; height=173.3±9.5 cm; weight=66.1±9.5 kg) performed 4 sessions comprising i) an all-out 30 s test and incremental test (TSLacmin); ii) 30 min of tethered swimming at constant intensity (2 sessions); iii) free-swimming time trials used to calculate critical velocity. Tethered swimming sessions used an acquisition system enabling maximum (Fmax) and mean (Fmean) force measurement and intensity variation. The tethered all-out test lasting 30 s resulted in hyperlactatemia of 7.9±2.0 mmol·l-1. TSLacmin presented a 100% success applicability rate, which is equivalent to aerobic capacity in 75% of cases. TSLacmin intensity was 37.7±7.3 N, while maximum force in the all-out test was 105±27 N. Aerobic and anaerobic TSLacmin parameters were significantly related to free-swimming performance (r=-0.67 for 100 m and r=-0.80 for 200 m) and critical velocity (r=0.80). TSLacmin estimates aerobic capacity in most cases, and both aerobic and anaerobic force parameters are well related to critical velocity and free swimming performance.

Novel paddle stroke analysis for elite slalom kayakers: Relationship with force parameters

This study was divided into two complementary parts. In Part 1, we proposed a novel paddle strokes analysis based on the force signal from a 30-s all-out tethered test; and compared these results with video recordings. In Part 2, we investigated the relationship between force data from the same test with paddle stroke results from both methods. Eleven male elite slalom kayakers (Brazilian national team) were evaluated. The tethered test was conducted for force parameters analysis (peak-force, mean-force, impulse). Video recording analysis was conducted, and the performed strokes (V.NumberPaddle) was counted and frequency (V.FrequencyPaddle) calculated by the V.NumberPaddle divided by 30 (i.e. total time of test). The new method consisted of performed strokes and frequency achievement from a load cell force signal analysis (S.NumberPaddle and S.FrequencyPaddle, respectively). Paired test-t did not show difference between methods results, but significant correlations were only obtained for the number of paddle strokes. Force parameters were only correlated with S.NumberPaddle and S.FrequencyPaddle. Overall, considering the theoretical and practical application, we propose that the new method should be used as an alternative to the video recording.

Influence of the previous cycling experience on psychophysiological parameters obtained from perceived exertion scales during aerobic and anaerobic tests

This study investigated the effect of previous cycling experience on psychophysiological parameters from aerobic and anaerobic tests. In this sense, while no difference in such parameters were visualized in both tests, significant diferences were obtainned in terms of physiological parameters (aerobic capacity and anaerobic power). In summary, it seems that only physiological parameters are dependent on the previous cycling experience.

Determinação do limiar anaeróbio por dois ajustes matemáticos em teste específico para canoagem Slalom

O estudo objetivou propor um teste especifico para identificar o limiar anaerobio (Lan) em atletas de canoagem slalom. O Lan foi determinado por teste progressivo ate a exaustao nas velocidades de 5,6,7,8,9 e 9,5km/h, realizado em lagoa onde comumente eram realizados os treinos. O Lan foi obtido por dois metodos matematicos: inspecao visual e bissegmenta- cao da curva lactacidemica (LanBI), e utilizacao das concentracoes fixas de lactato 4mM e 2,5mM (LanOBLA). O LanBI e LanOBLA foram analisados por Anova One-Way e correlacao de Pearson (p<0,05). O LanBI foi obtido em 6,98 ± 0,16 km/h, a 2,53±0,25mM, e o Lan OBLA 4,0 ocorreu em 7,80±0,21km/h, superestimando em 11,5% o LanBI.. Desse modo, e possivel determinar o Lan por teste especifico para canoistas e, se adotado o OBLA, a concentracao 2,5mM parece ser mais adequada a modalidade.

Determinación del umbral anaeróbico por dos métodos matemáticos en test específico en canotaje Slalom

O estudo objetivou propor um teste especifico para identificar o limiar anaerobio (Lan) em atletas de canoagem slalom. O Lan foi determinado por teste progressivo ate a exaustao nas velocidades de 5,6,7,8,9 e 9,5km/h, realizado em lagoa onde comumente eram realizados os treinos. O Lan foi obtido por dois metodos matematicos: inspecao visual e bissegmenta- cao da curva lactacidemica (LanBI), e utilizacao das concentracoes fixas de lactato 4mM e 2,5mM (LanOBLA). O LanBI e LanOBLA foram analisados por Anova One-Way e correlacao de Pearson (p<0,05). O LanBI foi obtido em 6,98 ± 0,16 km/h, a 2,53±0,25mM, e o Lan OBLA 4,0 ocorreu em 7,80±0,21km/h, superestimando em 11,5% o LanBI.. Desse modo, e possivel determinar o Lan por teste especifico para canoistas e, se adotado o OBLA, a concentracao 2,5mM parece ser mais adequada a modalidade.

Determination of anaerobic threshold by two mathematical methods in specific test on Slalom kayak

O estudo objetivou propor um teste especifico para identificar o limiar anaerobio (Lan) em atletas de canoagem slalom. O Lan foi determinado por teste progressivo ate a exaustao nas velocidades de 5,6,7,8,9 e 9,5km/h, realizado em lagoa onde comumente eram realizados os treinos. O Lan foi obtido por dois metodos matematicos: inspecao visual e bissegmenta- cao da curva lactacidemica (LanBI), e utilizacao das concentracoes fixas de lactato 4mM e 2,5mM (LanOBLA). O LanBI e LanOBLA foram analisados por Anova One-Way e correlacao de Pearson (p<0,05). O LanBI foi obtido em 6,98 ± 0,16 km/h, a 2,53±0,25mM, e o Lan OBLA 4,0 ocorreu em 7,80±0,21km/h, superestimando em 11,5% o LanBI.. Desse modo, e possivel determinar o Lan por teste especifico para canoistas e, se adotado o OBLA, a concentracao 2,5mM parece ser mais adequada a modalidade.