The capacity to rapidly generate and apply a great amount of force seems to play a key role in sprint running. However, it has recently been shown that, for sprinters, the technical ability to effectively orient the force onto the ground is more important than its total amount. The force-vector theory has been proposed to guide coaches in selecting the most adequate exercises to comprehensively develop the neuromechanical qualities related to the distinct phases of sprinting. This study aimed to compare the relationships between vertically-directed (loaded and unloaded vertical jumps, and half-squat) and horizontally-directed (hip-thrust) exercises and the sprint performance of top-level track and field athletes. Sixteen sprinters and jumpers (including three Olympic athletes) executed vertical jumps, loaded jump squats and hip-thrusts, and sprinting speed tests at 10-, 20-, 40-, 60-, 100-, and 150-m. Results indicated that the hip-thrust is more associated with the maximum acceleration phase (i.e., from zero to 10-m; r = 0.93), whereas the loaded and unloaded vertical jumps seem to be more related to top-speed phases (i.e., distances superior to 40-m; r varying from 0.88 to 0.96). These findings reinforce the mechanical concepts supporting the force-vector theory, and provide coaches and sport scientists with valuable information about the potential use and benefits of using vertically- or horizontally-based training exercises.

Objective The objective of this study was to evaluate the sleep quality, sleepiness, chronotype and the anxiety level of Brazilian Paralympics athletes before the 2008 Beijing Paralympic Games. Design Cross-sectional study. Setting Exercise and Psychobiology Studies Center (CEPE) and Universidade Federal de São Paulo, an urban city in Brazil. Participants A total of 27 Paralympics athletes of both genders (16 men and 11 women) with an average age of 28±6 years who practised athletics (track and field events) were evaluated. Main outcome measures Sleep quality was evaluated using the Pittsburgh Scale and the Epworth Sleepiness Scale to evaluate sleepiness. Chronotype was determined by the Horne and Östberg questionnaire and anxiety through the State-Trait Anxiety Inventory. The evaluations were performed in Brazil 10 days before the competition. Results The study's results demonstrate that 83.3% of the athletes that presented excessive daytime sleepiness also had poor sleep quality. The authors noted that 71.4% were classified into the morning type and 72% of the athletes who presented a medium anxiety level also presented poor sleep quality. Athletes with poor sleep quality showed significantly lower sleep efficiency (p=0.0119) and greater sleep latency (p=0.0068) than athletes with good sleep quality. Athletes who presented excessive daytime sleepiness presented lower sleep efficiency compared to non-sleepy athletes (p=0.0241). Conclusions The authors conclude that the majority of athletes presented poor sleep quality before the competition. This information should be taken into consideration whenever possible when scheduling rest, training and competition times.

The aims of this study were to estimate the magnitude of variability and progression in actual competitive and field vertical jump test performances in elite Paralympic sprinters with visual impairment in the year leading up to the 2015 Parapan American Games, and to investigate the relationships between loaded and unloaded vertical jumping test results and actual competitive sprinting performance. Fifteen Brazilian Paralympic sprinters with visual impairment attended seven official competitions (four national, two international and the Parapan American Games 2015) between April 2014 and August 2015, in the 100- and 200-m dash. In addition, they were tested in five different periods using loaded (mean propulsive power [MPP] in jump squat [JS] exercise) and unloaded (squat jump [SJ] height) vertical jumps within the 3 weeks immediately prior to the main competitions. The smallest important effect on performances was calculated as half of the within-athlete race-to-race (or test-to-test) variability and a multiple regression analysis was performed to predict the 100- and 200-m dash performances using the vertical jump test results. Competitive performance was enhanced during the Parapan American Games in comparison to the previous competition averages, overcoming the smallest worthwhile enhancement in both the 100- (0.9%) and 200-m dash (1.43%). In addition, The SJ and JS explained 66% of the performance variance in the competitive results. This study showed that vertical jump tests, in loaded and unloaded conditions, could be good predictors of the athletes’ sprinting performance, and that during the Parapan American Games the Brazilian team reached its peak competitive performance.

Etes participated in this study (28 males and 12 females). All athletes competed in International Paralympic competitions between 2004 and 2008. According to the visual classification, 14 athletes were T/F11, 15 were T/F12, and 11 were T/F13. A standardized report form was used to collect injury data during five competitions. Results Thirty-one athletes reported 77 sports injuries, with a prevalence of 78%, a clinical incidence of 1.93 injuries per athlete, and an incidence rate of 0.39 injuries per athlete per competition. Overuse injuries accounted for 82% and traumatic injuries 18% (P < 0.05). Small variations in the prevalence and clinical incidence of injury between sexes and visual classes were observed, but these were not statistically different (P > 0.05). The highest distribution of injury was in the lower limbs (87%), followed by spine (12%) and upper limbs (1%). The body regions most affected were the thighs (33.8%), lower legs (16.9%), and knees (9.1%). The most frequent diagnoses were spasms (26%), tendinopathies (23.4%), and strains (13%). Conclusions Elite visually impaired track and field Paralympic athletes present a pattern of overuse injuries predominantly affecting the lower limbs, particularly the thighs, lower legs, and knees. These injuries are associated with tendinopathies, muscle spasms, and strains. There were no apparent differences in injury characteristics between visual classes or sex....

Purpose: To examine the relationships between different loading intensities and movement velocities in the bench-press exercise (BP) in Paralympic powerlifters. Methods: A total of 17 national Paralympic powerlifters performed maximum dynamic strength tests to determine their BP 1-repetition maximum (1RM) in a Smith-machine device. A linear position transducer was used to measure movement velocity over a comprehensive range of loads. Linear-regression analysis was performed to establish the relationships between the different bar velocities and the distinct percentages of 1RM. Results: Overall, the correlations between bar velocities and %1RM were strong over the entire range of loads (R² .80–.91), but the precision of the predictive equations (expressed as mean differences [%] between actual and predicted 1RM values) were higher at heavier loading intensities (∼20% for loads ≤70% 1RM and ∼5% for loads ≥70% 1RM). In addition, it seems that these very strong athletes (eg, 1RM relative in the BP = 2.22 [0.36] kg·kg⁻¹, for male participants) perform BP 1RM assessments at lower velocities than those previously reported in the literature. Conclusions: The load–velocity relationship was strong and consistent in Paralympic powerlifters, especially at higher loads (≥70% 1RM). Therefore, Paralympic coaches can use the predictive equations and the reference values provided here to determine and monitor the BP loading intensity in national Paralympic powerlifters.

Athlete development in parasport is a complex domain. Evidence on the developmental trajectories of para-athletes is necessary to examine the critical determinants of specific para-athlete development models. Underpinned by the existing athlete development models to gather insights into the different developmental phases, this study explored how athletic career pathways in parasport are developed by identifying and describing disability-specific characteristics that influence each developmental phase. Para-athlete development was explored through the lens of 32 stakeholders from the Brazilian parasport context who participated in semi-structured interviews. Results ratified the complexity and individuality of para-athlete development, highlighting that the differences according to impairment groups, an early or late start in the sport and the classification, have implications for the development of the phases of athletic pathways in parasport. The findings lend weight toward the need for models other than those traditionally used for able-bodied athletes; rather, para-athlete development models need a disability-specific approach.