Functional plasticity of the ipsilateral primary sensorimotor cortex in an elite long jumper with below-knee amputation.

Functional plasticity of the sensorimotor cortex occurs following motor practice, as well as after limb amputation. However, the joint effect of limb amputation and intensive, long-term motor practice on cortical plasticity remains unclear. Here, we recorded brain activity during unilateral contraction of the hip, knee, and ankle joint muscles from a long jump Paralympic gold medalist with a unilateral below-knee amputation (Amputee Long Jumper, ALJ). He used the amputated leg with a prosthesis for take-off. Under similar conditions to the ALJ, we also recorded brain activity from healthy long jumpers (HLJ) and non-athletes with a below-knee amputation. During a rhythmic isometric contraction of knee extensor muscles with the take-off/prosthetic leg, the ALJ activated not only the contralateral primary sensorimotor cortex (M1/S1), but also the ipsilateral M1/S1. In addition, this ipsilateral M1/S1 activation was significantly greater than that seen in the HLJ. However, we did not find any significant differences between the ALJ and HLJ in M1/S1 activation during knee muscle contraction in the non-take-off/intact leg, nor during hip muscle contraction on either side. Region of interest analysis revealed that the ALJ exhibited a greater difference in M1/S1 activity and activated areas ipsilateral to the movement side between the take-off/prosthetic and non-take-off/intact legs during knee muscle contraction compared with the other two groups. However, difference in activity in M1/S1 contralateral to the movement side did not differ across groups. These results suggest that a combination of below-knee amputation and intensive, prolonged long jump training using a prosthesis (i.e. fine knee joint control) induced an expansion of the functional representation of the take-off/prosthetic leg in the ipsilateral M1/S1 in a muscle-specific manner. These results provide novel insights into the potential for substantial cortical plasticity with an extensive motor rehabilitation program.

Changes in Jumping and Throwing Performances in Age-Group Athletes Competing in the European Masters Athletics Championships between 1978 and 2017.

The results of master athletes have been used previously to examine the age-related differences in aerobic capacity, however, less research has been conducted on the variation of jumping and throwing performances with aging. Therefore, the aim of the present study of elite master athletes was to investigate (a) the age-related differences in throwing (i.e., discus, hammer, javelin, and shot put) and jumping events (i.e., high jump, long jump, pole vault, and triple jump) in 5-year age-group intervals from 35-39 to 95-99 years of elite master athletes, and (b) the trends in performance and sex differences. The top eight female and male finalists for each age group and in each event from 20 European Masters Athletics Championships held between 1978 and 2017 were considered. Overall, 13,673 observations from 4726 master athletes were analyzed. For each event separately, a mixed regression model was performed with sex, age group, calendar year, and interaction terms (sex-age group, sex-year) defined as fixed effects. Performances were improving over time with a linear trend overall for each event. Men had better performances as compared to women, (i.e., in triple jump the estimated difference was 2.58 m, p < 0.001). Performances declined with age for each event (i.e., in triple jump, compared with the age group 45-49 years, performance in the age group 35-39 years was 0.98 m better and performance in the age group 85-89 years was 6.24 m worse). The decline of male performances with age was either slower or faster than the decline of female performances depending on age groups and events.

Improved Performance in Master Runners Competing in the European Championships Between 1978 and 2014.

Schneider, AL, Nikolaidis, PT, and Knechtle, B. Improved performance in master runners competing in the European championships between 1978 and 2014. J Strength Cond Res 33(9): 2559-2569, 2019-The performance trends in elite runners have been well investigated, but we have no knowledge about performance trends and the difference between the sexes in elderly runners competing at a high level in varying distances. The purpose of this study was to investigate the performance of these age groups. Data from 17 European Championships held between 1978 and 2014 were analyzed for various race distances (i.e., 100, 200, 400, 800, 1,500, 5,000, 10,000 m, and marathon). Running speed for the top 8 female and male finalists for each age group (35-99 years, split into 5-year gaps) and each race distance were included. A 2-way analysis of variance compared the effects of sex, race distance, age group and calendar year on speed. Subsequent comparisons between race distances, age groups, or calendar years were performed using a post hoc Bonferroni's test. Our analysis shows that men were faster than women in all distances, and the difference between the sexes was greater in the shorter distances. Speed was higher for shorter distances than for longer distances. Younger participants were faster than older ones, and the effect of age group was the largest for the 200 m. There was a minor effect of calendar year on speed in the 100, 20, 1,500, 10,000 m and marathon, and a minor calendar year × sex interaction on running speed was shown for the 200 m. For athletes and coaches, the current study demonstrates that both male and female athletes improved their running performance over time and that the sex gap may have reached its limit.

Máxima velocidade aeróbia calculada pelo custo da frequência cardíaca: relação com a performance / Velocidad aeróbica máxima calculada por el costo del ritmo cardíaco: relación con el rendimiento / Maximal aerobic speed calculated by heart rate cost: relationship with performance

Objetivos. Comparar a máxima velocidade aeróbia (MVA) calculada pelo custo de oxigênio (vVO2max) e o custo da frequência cardíaca (vFCmax) com a medida direta da MVA (Vpico) e verificar a relação entre a vFCmax e a performance em provas de 10 e 15 km de corredores recreacionais de meia idade. Método. Participaram 21 corredores (idade: 30‐49 anos), subdivididos em 2 grupos a partir da idade (G1 e G2). Os participantes foram submetidos a um teste incremental contínuo máximo em laboratório para determinação do consumo máximo de oxigênio. A MVA foi determinada a partir das propostas apresentadas na literatura com base no vVO2max e no vFCmax. Além disso, foram realizadas 2 performances em pista de atletismo (10 e 15 km). Resultados. A menor diferença entre as médias observada para a Vpico foi em relação à vFCmax de Lacour et al. (0,0 km h–1; p > 0,05). A maior diferença foi em relação à vFCmax de Di Prampero (1,55 km h–1; p < 0,05). O mesmo padrão de diferenças foi observado quando analisado o G1 e G2. A vFCmax determinada a partir de 2 diferentes métodos propostos na literatura se correlacionou com as provas de 10 e 15 km (0,55 ≤ r ≤ 0,82; p < 0,05). Conclusões. A vFCmax em corredores recreacionais de meia idade tem elevada relação com as performances de 10 e 15 km e não foi diferente da Vpico (para vFCmax de Lacour et al.), apresentando resultados semelhantes aos observados pelos métodos baseados no custo de oxigênio (AU)

Objetivo: Comparar la velocidad aeróbica máxima (VAM), calculada a través del costo de oxígeno (vVO2max) y del costo de la frecuencia cardíaca (vFCmáx), con la medida directa de la VAM (Vpico) y verificar la relación entre la vFCmax y la performance de 10 e 15 km de corredores recreativos de mediana edad. Método: Participaron 21 corredores recreativos (edades: 30-49 años) subdivididos en 2 grupos por edad (G1 y G2). Los participantes se sometieron a un test incremental continuo máximo en laboratorio para la determinación del consumo máximo de oxígeno. La MVA fue determinada a través de las propuestas presentadas en la literatura basada en el vVO2max y el vFCmáx. Además, se realizaron 2 pruebas en pista de atletismo (10 e 15 km). Resultados: La menor diferencia entre las medias observadas para la Vpico fue en relación con la vFCmax de Lacour et al. (0,0 km h-1; p > 0,05). La mayor diferencia fue en relación con la vFCmax de Di Prampero (1,55 km h-1; p < 0,05). El mismo patrón de diferencias fue observado cuando se analizaron el G1 y G2. La vFCmáx determinada a través de 2 distintos métodos propuestos en la literatura se correlacionó con las pruebas de 10 y 15 km (0,55 ≤ r ≤ 0,82; p < 0,05). Conclusiones: La vFCmáx, en corredores recreativos de mediana edad, tiene alta correlación con las pruebas de 10 y 15 km y no fue diferente de la Vpico (para vFCmáx de Lacour et al.), presentando resultados similares a los observados por los métodos basados en el costo de oxígeno

Objectives. To compare maximal aerobic speed (MAS) calculated by oxygen cost (vVO2max) and heart rate cost (vHRmax) with the direct measurement of MAS (Vpeak) and to verify the relationship between vHRmax and 10‐ and 15‐km performance in middle‐age recreationally runners. Method. Twenty one recreationally runners participated in this study (age: 30 to 49 years), allocated in two groups according to age (G1 and G2). Participants were submitted to an incremental continuous test of maximal effort in laboratory to determine maximal oxygen uptake. MAS was determined according to proposes presented in literature based on vVO2max and vHRmax. Besides, it was performed two performances in field track (10 and 15 km). Results. The lowest difference between the mean values observed and Vpeak was in relation to vHRmax from Lacour et al. (0.0 km h–1; p > 0.05). The highest was in relation to vHRmax from di Prampero (1.55 km h–1; p < 0.05). The same pattern of differences was observed when G1 and G2 were analyzed. The vHRmax determined according to two different methods presented in literature showed to be correlated with 10 and 15 km performances (0.55 ≤ r ≤ 0.82; p < 0.05). Conclusions. The vHRmax in middle‐aged recreational runners has elevated correlation with 10 and 15 km performances and was not different from Vpeak (to vHRmax from Lacour et al.) showing similar results than the method based on oxygen cost (AU)

XV Congreso nacional de la federación española de medicina del deporte / No disponible

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An improvement index to quantify the evolution of performance in running.

Improvements in track and field sports have been attributed to factors such as population increase, drugs and new technologies, but previous research has found it difficult to distinguish the contributions from specific influences. Here it is shown how this is possible by means of a performance improvement index based on useful work done combined with modelling of the annual top 25 performances. The index was set to 100 in 1948 and showed that, by 2012, it had increased in running events to between 110.5 and 146.7 (men's 100 m and marathon). Underlying global effects accounted for the majority of all improvements (16.2 to 46.7) with smaller influences attributable to an influx of African runners (3.6 to 9.3), and a 4-year oscillation that arose from staging of the Olympic Games (±0.2 to ±0.6). Performance decreased with the introduction of compulsory random drug testing (-0.9 to -3.9) the World Anti-Doping Agency (WADA; -0.5 to -2.5) and fully automated timing (-0.6 to -2.5). Changes in elite sporting performance since the 1890s are attributable to societal changes caused by the industrial revolution and globalisation superimposed on millennia of human evolution.

Which lap is the slowest? An analysis of 32 world mile record performances.

OBJECTIVES: The pacing strategies adopted by world-record breakers during the 1-mile footrace in order to evaluate different models for the biological basis of pacing was determined in this study. METHODS: Lap times in 32 world record performances were analysed. Average times for each of the four laps and as percentages of total race time were calculated. RESULTS: The slowest laps in 90% of races were either the second (34%) or the third (56%) laps. In only two (6%) records was the final lap the slowest, whereas in 24 (76%), it was either the fastest (38%) or the second fastest (38%) lap. Mean times for the second and third laps were both significantly slower than were times for the first or final laps, but there was no significant difference in times for the first and final lap. CONCLUSION: The finding that world record beaters run the final lap in their quickest mile races faster than the second and third laps matches findings for races at longer distances. The presence of this "end spurt" suggests that the pacing strategy is regulated "in anticipation" and is not purely the result of a developing "peripheral fatigue".

Trends and random fluctuations in athletics.

Improvements in the results of athletic competitions are often considered to stem from better training and equipment, but elements of chance are always present in athletics and these also contribute. Here we distinguish between these two effects by estimating the range into which athletic records would have fallen in the absence of systematic progress and then comparing this with actual performance results. We find that only 4 out of 22 disciplines have shown a systematic improvement, and that annual best results worldwide show saturation in some disciplines.

Forecasting of top athletic performance.

The limiting factors of top athletic performance and the psycho-physiological mechanisms involved remain controversial. The aim of this study was to attempt a prediction of world records (WR) for the next ten years in five athletic track and field and events. Our prediction has been produced by means of computer--aided mathematical models. In short, polynomials that could best approximate the WR of the last decades have been calculated and projected over the period 2000-2010. The predicted values for the year 2010 point to an improvement rate of the WR considered varying between 0.2% and 10.3%, depending on event and gender. Those values could be influenced by the use of better sports equipment, better nutrition and training and especially by the impact of doping and of anti-doping measures.