In sprint kayaking the role that paddling technique plays in optimizing paddle forces and resultant kayak kinematics is still unclear. The aim of this study was to analyze the magnitude and shape of the paddle force-time curve at different stroke rates, and their implications for kayak performance. Ten elite kayak paddlers (5 males and 5 females) were analyzed while performing 2000-m on-water trials, at 4 different paces (60, 80, and 100 strokes per minute, and race pace). The paddle and kayak were instrumented with strain gauges and accelerometers, respectively. For both sexes, the force-time curves were characterized at training pace by having a bell shape and at race pace by a first small peak, followed by a small decrease in force and then followed by a main plateau. The force profile, represented by the mean force/peak force ratio, became more rectangular with increasing stroke rate (F[3,40] = 7.87, P < .01). To obtain a rectangular shape to maximize performance, kayak paddlers should seek a stronger water phase with a rapid increase in force immediately after blade entry, and a quick exit before the force dropping far below the maximum force. This pattern should be sought when training at race pace and in competition.

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We investigated the effect of the intervention using the BFR method on functional capacity after 16 weeks in elderly women. In a controlled clinical trial, 23 women were randomly allocated into two groups, low-intensity exercise with blood flow restriction (LI + BFR, N = 11, Age: 69.40 ± 5.73) and control group (CG, N = 12, Age: 69.00 ± 6.39). The LI + BFR group had a volume of 75 repetitions at 20-30 % of 1RM and 3-4 sets per exercise (30, 15, 15 and repetitions with 30" rest between sets). The CG did not undergo any type of exercise. Functional capacity, anthropometry and sarcopenia were verified through a battery of tests before and after 16 weeks. The LI + BFR group had significant improvement in performance in Handgrip strength, Chair Stand, Arm curl, 2.44 Up-and-Go and 6 min walk, Sit-andreach and Back Scratch (p<0.05) after the intervention. The elderly women were still classified as sarcopenic, despite the improvement in the Muscle Mass Index (p<0.01). CG did not present significant changes. The BFR method can be an effective in the intervention process using physical exercise as an auxiliary strategy in the control of sarcopenia, providing a physical profile during the aging process.

Background: The basketball jump shot (JS) is consensually considered as a high-complexity specific motor skill, with a complex teaching and learning processes involved. The aim of this paper was to conduct a systematic review of the literature on the JS performance among youth basketball players. Methods: The data search was made according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) in the Institute for Scientific Information (ISI) Web of Knowledge, PubMed, Scopus and Sportdiscus databases until March 2021. Results: The results suggest that JS performance of youth basketball players is influenced by (i) distance to the basket, (ii) fatigue, (iii) presence of a defender and (iv) visual information available. Conclusion: This research emphasizes the crucial need for players and coaches to promote training situations matching the game reality to develop successful shooting performance of youth basketball players.

We purposed to study energy expenditure, power output and gross efficiency during kayak ergometer exercise in 12 elite sprint kayakers. 6 males (age 24.2±4.8 years, height 180.4±4.8 cm, body mass 79.7±8.5 kg) and 6 females (age 24.3±4.5 years, height 164.5±3.9 cm, body mass 65.4±3.5 kg), performed an incremental intermittent protocol on kayak ergometer with VO2 and blood lactate concentration assessment, a non-linear increase between power output and energy expenditure being observed. Paddling power output, energy expenditure and gross efficiency corresponding to VO2max averaged 199.92±50.41 W, 75.27±6.30 ml.kg - 1.min - 1, and 10.10±1.08%. Male kayakers presented higher VO2max, power output and gross efficiency at the VO2max, and lower heart rate and maximal lactate concentration than females, but no differences were found between genders regarding energy expenditure at VO2max. Aerobic and anaerobic components of energy expenditure evidenced a significant contribution of anaerobic energy sources in sprint kayak performance. Results also suggested the dependence of the gross efficiency on the changes in the amount of the aerobic and anaerobic contributions, at heavy and severe intensities. The inter-individual variance of the relationship between energy expenditure and the corresponding paddling power output revealed a relevant tracking for females (FDγ=0.73±0.06), conversely to the male group (FDγ=0.27±0.08), supporting that some male kayakers are more skilled in some paddling intensities than others.