100-m Race Research Articles

Reliability and Validity of a Novel Trunk-Strength Assessment for High-Performance Sprint Flat-Water Kayakers.

To determine the reliability and validity of a novel trunk maximal isometric force assessment involving 7 different tasks with 200-m times for elite sprint flat-water kayakers. Ten elite sprint flat-water kayakers performed a series of maximal isometric voluntary contractions (MVCs) on 2 separate days to assess reliability. MVC force was assessed as the participants sat on a modified kayak ergometer and applied their maximal isometric force to a uniaxial load cell during 7 different tasks. The 7 tasks of interest were a seated trunk-forward flexion, bilateral (left and right) rotational pulls, bilateral rotational pushes, and a sport-specific bilateral kayak-stroke simulation. Twenty elite flat-water kayak athletes (10 male and 10 female) participated in the validity portion by completing the series of tasks in conjunction with a 200-m race. MVC force values ranged from 84 to 800N across all participants and all tasks. The average coefficient of variation of the 7 tasks ranged from 2.4% to 7.7%. Regression analysis showed Pearson correlations ranging from -.84 to -.22 for both absolute and relative values with 200-m performance times. MVC force measured in each task was considered reliable as a small degree of variance between trials was found. The summation of the 7 trunk scores showed very strong correlations with on-water performance, indicating that this assessment is valid for elite sprint kayakers.

Effect of duration of tapering on 100-m freestyle performance in swimmers

Objective: The aim of this study was to analyze the effect of tapering duration on 100-m freestyle performance in swimmers. Method: This is an experimental research with 16 weeks’ duration. Participants were 37 male swimmers aged between 15 and 17 years. The 100-m freestyle performance was evaluated before of the season start (pre-experiment), at the end of last week of each mesocycle (Preparatory, Specific I and Specific II) and the end of each week in the tapering phase. The performance was evaluated from the simulation of the 100-m freestyle race. Results: It was identified time effect for the 100-m freestyle performance (p < 0.001). Conclusion: It was concluded that two weeks of tapering were enough for the enhancement of 100-m freestyle performance.

Fortune Favors the Brave: Tactical Behaviors in the Middle-Distance Running Events at the 2017 IAAF World Championships.

To assess tactical and performance factors associated with progression from qualification rounds in the 800-m and 1500-m running events at the 2017 International Association of Athletics Federations World Championships. Official results were used to access final and intermediate positions and times, as well as performance characteristics of competitors. Shared variance between intermediate positions and rank order lap times with finishing positions were calculated, along with probability of automatic qualification, for athletes in each available race position at the end of every 400-m lap. Differences in race positions and lap times relative to season's best performances were assessed between automatic qualifiers, fastest losers, and nonqualifiers. Race positions at the end of each 400-m lap remained more stable through 800-m races than 1500-m races. Probability of automatic qualification decreased with both race position and rank order lap times on each lap, although rank order lap times accounted for a higher degree of shared variance than did intermediate position. In the 1500-m event, fastest losers ran at a higher percentage of season's best speed and adopted positions closer to the race lead in the early stages. This was not the case in the 800-m. Intermediate positioning and the ability to produce a fast final race segment are strongly related to advancement from qualification rounds in middle-distance running events. The adoption of a more "risky" strategy characterized by higher speeds relative to season's best may be associated with an increased likelihood of qualification as fastest losers in the 1500-m event.

Maximal Upper-Body Strength and Oxygen Uptake Are Associated With Performance in High-Level 200-m Sprint Kayakers.

Pickett, CW, Nosaka, K, Zois, J, Hopkins, WG, and Blazevich, AJ. Maximal upper-body strength and oxygen uptake are associated with performance in high-level 200-m sprint kayakers. J Strength Cond Res 32(11): 3186-3192, 2018-Current training and monitoring methods in sprint kayaking are based on the premise that upper-body muscular strength and aerobic power are both important for performance, but limited evidence exists to support this premise in high-level athletes. Relationships between measures of strength, maximal oxygen uptake (V[Combining Dot Above]O2max), and 200-m race times in kayakers competing at national-to-international levels were examined. Data collected from Australian Canoeing training camps and competitions for 7 elite, 7 national, and 8 club-level male sprint kayakers were analyzed for relationships between maximal isoinertial strength (3 repetition maximum bench press, bench row, chin-up, and deadlift), V[Combining Dot Above]O2max on a kayak ergometer, and 200-m race time. Correlations between race time and bench press, bench row, chin-up, and V[Combining Dot Above]O2max were -0.80, -0.76, -0.73, -0.02, and 0.71, respectively (90% confidence limits ∼±0.17). The multiple correlation coefficient for 200-m race time with bench press and V[Combining Dot Above]O2max was 0.84. Errors in prediction of 200-m race time in regression analyses were extremely large (∼4%) in relation to the smallest important change of 0.3%. However, from the slopes of the regressions, the smallest important change could be achieved with a 1.4% (±0.5%) change in bench-press strength and a 0.9% (±0.5%) change in V[Combining Dot Above]O2max. Substantial relationships were found between upper-body strength or aerobic power and 200-m performances. These measures may not accurately predict individual performance times, but would be practicable for talent identification purposes. Training aimed at improving upper-body strength or aerobic power in lower performing athletes could also enhance the performance in 200-m kayak sprints.

Effects of acute psychological stress on athletic performance in elite male swimmers.

While physical activity has been shown to affect psychological as well as physiological stress responses, less research has explored the effects of acute stress on athletic performance. The current study hence aimed to investigate the effect of an acute psychological stress (APS) provocation on performance and plasma lactate concentration during a following 200-m swim race among elite male swimmers. Furthermore, associations between physiological stress responses (salivary cortisol and testosterone), and outcome measures (speed and lactate) were explored. Twenty-three elite male swimmers participated in an experimental counterbalanced within-group repeated measures design consisting of an APS provocation followed by a 200-m race and, on a separate day, a control race without prior stress exposure. Salivary cortisol and testosterone were collected prior to each race. Race time was recorded, and serum lactate was collected immediately following, and five min after completed race. Race speed was significantly slower (1.53 [95% CI: 0.08-2.79] seconds) following the APS provocation than under control conditions. Prerace cortisol levels were positively associated with lactate response when preceding stress exposure was present (rho =0.483 immediately, and rho=0.429 five minutes post race, P<0.05). Under control conditions however, both increased testosterone (rho =-657, P=0.001) and cortisol (rho =-0.491, P=0.020) levels were associated with faster race times. The results indicated a negative impact of APS exposure on athletic performance. Further, potential beneficial effects on performance from physiological stress responses (as reflected by salivary cortisol and testosterone) may be diminished during performance following an APS provocation, compared with a regular non-provoked performance situation.

Association between Forefoot Bone Length and Performance in Male Endurance Runners.

Recently, we reported that the forefoot bones were longer in sprinters than in non-sprinters, and that longer forefoot bones correlated with higher sprint performance in sprinters. To further understand the superiority of long forefoot bones in athletic performance, we examined whether forefoot bone length was associated with running performance in endurance runners. The length of the forefoot bones of the big and second toes were measured using magnetic resonance imaging in 45 male well-trained endurance runners and 45 male untrained subjects. After normalization with the foot length, it was found that the forefoot bones of the big and second toes were significantly longer in endurance runners than in untrained subjects (P<0.05 for both). Furthermore, longer forefoot bones of the big toe, but not of the second toe, correlated significantly with better personal best 5000-m race time in endurance runners (r=-0.322, P=0.031). The present findings demonstrated that forefoot bones were longer in endurance runners than in untrained subjects. These findings were similar to our findings for sprinters. In addition, we found that longer forefoot bones may be advantageous for achieving higher running performance in endurance runners.

Do novice and experienced rowers adopt different pacing strategies and do their physiological and metabolic responses show optimisation?

&lt;p&gt;El objetivo fue evaluar las estrategias de ritmo y las respuestas metabólicas y fisiológicas de remeros novatos y experimentados, en distancia de 2000m. La muestra estuvo compuesta por 7 remeros universitarios y de clubes, 5 de los cuales eran novatos (edad 22.4±2.6 años, altura 182.6±8.4 cm, peso 79.7±8.9 kg), y 2 experimentados (edad 23.0±4.2 años, altura 194.1±4.1 cm, peso 90.3±2.0 kg). Todos los participantes realizaron una prueba de 2000m en un ergómetro de remo, seguidos por 3 pruebas en orden aleatorio (500m, 1000m, 1500m) a la velocidad y tiempo de carrera establecidos según la primera prueba de 2000m. La última sesión fue un test de &lt;sub&gt;2max&lt;/sub&gt;. Durante estas pruebas se realizó análisis de gases, hematología, frecuencia cardiaca, tiempos parciales, velocidad de carrera y distancias. La acumulación de lactato en sangre (BLa) en los remeros novatos se incrementó progresivamente y se estabilizó en los últimos 500m. Los remeros experimentados aumentaron gradualmente la acumulación de lactato, pero lo mantuvieron en el tercer cuarto (1000-1500m), lo que les permitió mayor acumulación en el cuarto final (1500-2000m). El volumen de consumo de oxígeno ( &lt;sub&gt;2&lt;/sub&gt;) aumentó linealmente hasta los 500m finales en los remeros experimentados, mientras que en los remeros novatos fluctuó durante toda la prueba. Respecto al ritmo, los remeros novatos siguieron la estrategia “all-out” esperada, mientras que, inesperadamente, los remeros experimentados disminuyeron la velocidad progresivamente hasta el punto medio (1000m), en el que mantuvieron una velocidad de 5.10m&lt;sup&gt;.&lt;/sup&gt;s&lt;sup&gt;-1&lt;/sup&gt;. Estos resultados sugieren que a un determinado nivel fisiológico y metabólico, los remeros experimentados están más adaptados a las demandas de una regata de remo de 2000m. Sin embargo, parece que no siempre siguen una estrategia “J-Shaped”.&lt;/p&gt;

Outcome of Low-Invasive Local Split-Thickness Lengthening for Iliotibial Band Friction Syndrome.

Conventional surgical methods for iliotibial band friction syndrome (ITBFS) may affect the iliotibial band (ITB), delaying return to sports activities or impeding performance. We have developed a minimally invasive method. This study retrospectively analyzed the outcomes of this procedure in individuals with ITBFS. This study included 34 knees of 31 individuals. Surgery involved lengthening the central part of the ITB by splitting it into a superficial and a deep layer, maintaining the anterior and posterior fibers immediately above the lateral epicondyle. Outcomes included time to resume sports activity, personal best times to run a 5000-m race before and after surgery, and 2-month post-surgery muscle strengths. The mean postoperative time to return to competition was 5.8 weeks. Personal best times of 5000-m race improved in 13 of 17 runners. Two months post-surgery, the mean extensor muscle strengths on the healthy and affected sides did not significantly differ nor did the flexor muscle strengths. In ITBFS, the ITB itself is normal. Lengthening the limited region of the ITB immediately above the lateral femoral epicondyle removes the cause of ITBFS, with a reduction in inflammation. This technique resulted in early return to competition without degrading performance.

Potential Relationship between Passive Plantar Flexor Stiffness and Running Performance.

The present study aimed to determine the relationship between passive stiffness of the plantar flexors and running performance in endurance runners. Forty-eight well-trained male endurance runners and 24 untrained male control subjects participated in this study. Plantar flexor stiffness during passive dorsiflexion was calculated from the slope of the linear portion of the torque-angle curve. Of the endurance runners included in the present study, running economy in 28 endurance runners was evaluated by measuring energy cost during three 4-min trials (14, 16, and 18 km/h) of submaximal treadmill running. Passive stiffness of the plantar flexors was significantly higher in endurance runners than in untrained subjects. Moreover, passive plantar flexor stiffness in endurance runners was significantly correlated with a personal best 5000-m race time. Furthermore, passive plantar flexor stiffness in endurance runners was significantly correlated with energy cost during submaximal running at 16 km/h and 18 km/h, and a trend towards such significance was observed at 14 km/h. The present findings suggest that stiffer plantar flexors may help achieve better running performance, with greater running economy, in endurance runners. Therefore, in the clinical setting, passive stiffness of the plantar flexors may be a potential parameter for assessing running performance.

Relationship between Achilles tendon length and running performance in well-trained male endurance runners.

This study aimed to determine the relationship between Achilles tendon (AT) length and running performance, including running economy, in well-trained endurance runners. We also examined the reasonable portion of the AT related to running performance among AT lengths measured in three different portions. The AT lengths at three portions and cross-sectional area (CSA) of 30 endurance runners were measured using magnetic resonance imaging. Each AT length was calculated as the distance from the calcaneal tuberosity to the muscle-tendon junction of the soleus, gastrocnemius medialis (GMAT ), and gastrocnemius lateralis, respectively. These AT lengths were normalized with shank length. The AT CSA was calculated as the average of 10, 20, and 30mm above the distal insertion of the AT and normalized with body mass. Running economy was evaluated by measuring energy cost during three 4-minutes submaximal treadmill running trials at 14, 16, and 18km/h, respectively. Among three AT lengths, only a GMAT correlated significantly with personal best 5000-m race time (r=-.376, P=.046). Furthermore, GMAT correlated significantly with energy cost during submaximal treadmill running trials at 14km/h and 18km/h (r=-.446 and -.429, respectively, P<.05 for both), and a trend toward such significance was observed at 16km/h (r=-.360, P=.050). In contrast, there was no correlation between AT CSA and running performance. These findings suggest that longer AT, especially GMAT , may be advantageous to achieve superior running performance, with better running economy, in endurance runners.

Keynote Address (November 2016): Zika Virus Disease in the Americas: A Storm in the Making.

.More than 700,000 cases of Zika virus (ZIKAV) disease have been officially reported to the Pan American Health Organization (PAHO) from 48 countries and territories of the Americas. The response led by the PAHO and partners suggests major lessons of this outbreak. A seemingly innocuous pathogen became the new villain, causing fear, economic losses and, most importantly, debilitating birth defects and neurological problems, reaffirming the well-known war principle of never to underestimate one's opponent. The ZIKAV tested public health capacities under the International Health Regulations, highlighting the need for continued investment in health security. Last but not least, the lack of appropriate tools was another reminder of the pressing need for innovative solutions to persistent problems. Latin America and the Caribbean have approximately 500 million persons living in areas at risk for transmission of ZIKAV. The fight against ZIKAV is not a 100-m race, but rather a marathon in which science and public health need to work hand in hand for the benefit of our peoples.

Lower extremity kinematics of curve sprinting displayed by runners using a transtibial prosthesis

ABSTRACTThe purpose of the study was to determine if the kinematics exhibited by skilled runners wearing a unilateral, transtibial prosthesis during the curve section of a 200-m sprint race were influenced by interaction of limb-type (prosthetic limb (PROS-L) vs. nonprosthetic limb (NONPROS-L)) and curve-side (inside and outside limb relative to the centre of the curve). Step kinematics, toe clearance and knee and hip flexion/extension, hip ab/adduction for one stride of each limb were generated from video of 13 males running the curve during an international 200 m transtibial-classified competition. Using planned comparisons (P < 0.05), limb-type and curve-side interactions showed shortest support time and lowest hip abduction displacement by outside-NONPROS-L; shortest step length and longest time to peak knee flexion by the inside-PROS-L. For limb-type, greater maximum knee flexion angle and lower hip extension angles and displacement during support and toe clearance of PROS-Ls occurred. For curve-side, higher hip abduction angles during non-support were displayed by inside-limbs. Therefore, practitioners should consider that, for curve running, these kinematics are affected mostly by PROS-L limitations, with no clear advantage of having the PROS-L on either side of the curve.

The knee extensor moment arm is associated with performance in male sprinters.

Although large knee extensor torque contributes to superior sprint performance, previous findings have indicated that the quadriceps cross-sectional area (CSA), a pivotal morphological regulator of knee extensor torque, is not correlated with performance in sprinters. We hypothesized that the knee extensor moment arm (MA), another main morphological regulator of knee extensor torque, may affect sprint performance. To test this hypothesis, we examined the relationship between knee extensor MA and sprint performance. The quadriceps CSA and knee extensor MA in 32 well-trained male sprinters and 32 male non-sprinters were measured using magnetic resonance imaging. Knee extensor MA, but not quadriceps CSA, was greater in sprinters than in non-sprinters (P = 0.013). Moreover, knee extensor MA, but not the quadriceps CSA, was correlated with the personal best time in a 100-m race in sprinters (r = -0.614, P < 0.001). Furthermore, among 24 sprinters who participated in the 60-m sprint test, knee extensor MA was correlated with sprinting velocities in the acceleration (r = 0.717, P < 0.001) and maximum speed (r = 0.697, P < 0.001) phases. The present study demonstrates that the knee extensor MA is greater in sprinters than in non-sprinters, and this morphological structure in sprinters is associated with sprint performance. Therefore, for the first time, we provided evidence that a greater knee extensor MA in sprinters may be an advantageous for achieving superior sprint performance.

Effects of Color on the Athletic Performance of Short-Distance Runners

Colors have the effect of healing and exciting us. In recent years, the number of institutions using the color red rather than blue for tartan tracks has increased. Some research has claimed that blue tartan was put into practical use with the intention of improving performance. However, there is no agreement on the influence of color on performance among runners. Subjects were divided into two groups; group A specializing in the 100-m and 200-m races and group B specializing in the 400 m race. We measured the anaerobic power and V O2max. In group A, better recordings were obtained for anaerobic power when wearing red goggles versus blue ones, while better recordings were obtained with V O2max when wearing blue goggles. In group B, we could not determine whether or not color had a positive effect on performance. We examined the effect of color on the anaerobic power and cardiopulmonary function of sprint runners in track and field.

Sync or separate? No compelling evidence for unintentional interpersonal coordination between Usain Bolt and Tyson Gay on the 100-meter world record race.

In a recent observation article in Journal of Experimental Psychology: Human Perception and Performance (JEP:HPP; Varlet & Richardson, 2015) the 100-m sprint final of the World Championship in Athletics in Berlin of 2009 (i.e., the current world record race) was analyzed. That study reported occurrence of spontaneous, unintentional interpersonal synchronization between Usain Bolt and Tyson Gay, the respective winner and runner-up of that race. In the present commentary article, however, we argue that the results and conclusion of that study cannot be warranted because of methodological shortcomings. We addressed the same research question and reassessed the same race using an alternative data analysis method. These results revealed that as yet there is no sufficient ground to conclude that in the 100-m world record race synchronization occurred between Bolt and Gay. Yet, our reanalysis suggested that even at this very elite level the individual movement frequencies did seem to vary to such an extent that synchronization would theoretically still be possible, thereby providing incentives for further examination of potential unintentional synchronization in coactive sports. (PsycINFO Database Record

Acute effects of different conditioning activities on running performance of sprinters.

This study investigated acute effects of different conditioning activities on sprint performance of collegiate sprinters using a randomized, crossover design. Male sprinters (N = 10; 20.1 ± 0.6 years; 174.6 ± 4.4 cm; 66.7 ± 3.5 kg; 100-m race personal best time, 11.46 ± 0.57 s; means ± SDs) performed two 60-m sprints and one of three treatments within the same day, with an interval of 2 days between the treatments. The baseline sprint was followed by one of three different conditioning activities: mini-hurdles, bounding jumps, or a free sprint. Participants then performed the post treatment sprint. In the mini-hurdle drill, the participants ran over 10 × 10 mini-hurdles (height 22 cm) as fast as possible. In the bounding jump drill, the participants performed three 60-m bounding jumps as explosively and far as possible, with 3 min intervals between trials. In the free-sprint conditioning activity, the participants performed a 60-m maximal sprint twice, with a 5 min interval between sprints. Sprint kinematics in the baseline and post treatment sprints were recorded using a high-speed camera (300 Hz). Using these films, sprint time, running velocity, step length, and step frequency were analyzed over 10 m intervals. The results of ANOVAs indicated that the mini-hurdle drill increased the maximal sprint velocity (3.2 %) and maximal step frequency (3.3 %); the other conditioning activities had no such effects. Step length did not change after any of the conditioning activities. These results suggest that conditioning activities with mini-hurdles, which require movements with a high step frequency, acutely enhances velocity during sprinting, possibly as a result of increasing step frequency.

Effects of compression clothing on speed-power performance of elite Paralympic sprinters: a pilot study.

BackgroundCompression garments are thought to aid performance in some selected speed–power activities owing to improved sensory feedback and proprioception. The aim of this study was to test the effects of using compression garments on speed and power-related performances in elite sprinters with visual impairment, who rely more on proprioception to perform than their Olympic peers. Eight top-level Paralympic sprinters competing in 100- and 200-m races performed, in the following order: unloaded squat jump (SJ), loaded jump squat (JS) and sprint tests over 20- and 70-m distances; using or not the compression garment. The maximum mean propulsive power value obtained during the JS attempts (starting at 40 % of their body mass, after which a load of 10 % of body mass was progressively added) was considered for data analysis purposes. The athletes executed the SJ and JS attempts without any help from their guides. Magnitude-based inference was used to analyze the results. FindingsThe unloaded SJ was possibly higher in the compression than the placebo condition (41.19 ± 5.09 vs. 39.49 ± 5.75 cm). Performance differences in the loaded JS and sprint tests were all rated as unclear. ConclusionsIt was concluded that the acute enhancement in vertical jump ability should be explored in the preparation of Paralympic sprinters during power-related training sessions. However, chronic effects in Paralympic athletes wearing compression garments need to be further tested, in order to support its use as a specific training aid.

Unobtrusive and Energy-Efficient Swimming Exercise Tracking Using On-Node Processing

Body-worn sensors for movement analysis in swimming have to be unobtrusive and energy-efficient. We present a swimming exercise tracker for the unobtrusive positioning at the back of the head and an energy-efficient analysis using an on-node implementation. To develop the system, we collected head kinematics from 11 subjects in two 200-m medley races comprising breaks, turns, and four swimming styles. Each subject was equipped with a 6-D inertial measurement unit and completed one session in rested and fatigued state. Data were analyzed with a classification system, whereby different classifiers, window sizes, and feature sets were evaluated. Algorithm selection for on-node processing was performed on the basis of classifier accuracy and computational cost. The algorithm with the best tradeoff in accuracy and computational cost was selected and had a classification rate of 85.4%. Energy consumption of both on-node processing and Bluetooth streaming was evaluated on the Shimmer sensor platform. The results revealed energy savings of over 60% when data were processed on the sensor node. The presented analysis approach can be easily applied to other data analysis tasks, and the presented toolchain can support the rapid development of wearable systems in sports and healthcare.

Land-based Warm-up Is Inferior To Water-based Warm-up For 100m Freestyle Swimming Performance

In swimming competitions, athletes must usually complete their pool-based warm-up 20 minutes before their race time, and spend the intervening time out of the water in a call room. It is possible that some of the beneficial effects of completing a warm-up may be lost during this time. PURPOSE: The aim of this study was to investigate the effect of a land-based warm up (LAND) on 100m freestyle swimming performance, compared to a traditional water-based warm-up (WATER). METHODS: Twenty-two national level swimmers ( 11 female, age 17.9 ± 2.5 years, 100m freestyle personal best 59.8 ± 2.8 s; 11 male, age 18.6 ± 2.8 years, 100m freestyle personal best 52.8 ± 1.91 s) completed both WATER and LAND warm-ups prior to a 100m race, in a randomised cross-over design. WATER consisted of 2100m of drills at various intensities, taking approximately 30 minutes to complete, and followed by a 20-minute call-room wait. LAND consisted of a time-matched programme of dynamic mobility exercises, pulse-raisers, and muscle activation exercises, again followed by a 20-minute call-room wait. Race time, stroke rate (SR) and distance per stroke (DPS) were obtained from race video analysis; heart rate (HR) and rating of perceived exertion (RPE) were recorded before and after the warm-up and race. Paired T-tests were performed to test for significant differences between conditions. RESULTS: Race time was faster after WATER than LAND (58.10 ± 4.39 s vs. 59.00 ± 4.04 s, p = 0.001, Cohen’s d ES 0.2), there were no significant differences in SR or DPS. HR was higher after WATER than LAND (153 ± 14 bpm vs. 140 ± 21 bpm, p = 0.024, Cohen’s d ES 0.7); RPE was lower after WATER than LAND (median RPE 13 vs. 15, p = 0.01). CONCLUSIONS: The land-based warm-up was not sufficient to prepare swimmers for a 100 m freestyle race; this may be due to the lower physiological intensity (as determined by HR), or perhaps the absence of ‘water feel’ (not measured). Further work should investigate the effect of a combined water and land warm-up to more closely replicate the call-room scenario.

Are the knee and ankle angles at contact related to the tendon properties of lower limbs in long distance runners?

The purpose of this study was to investigate whether the knee and ankle angles at contact during running were related to the elastic properties of tendon structures in knee extensors and plantar flexors and performance in trained long distance runners. Thirty-two highly trained male long distance runners participated in this study. Elongation of tendon structures in knee extensors and plantar flexors were measured using ultrasonography while subjects performed ramp isometric contractions up to the voluntary maximum. The relationship between estimated muscle force and tendon elongation was fit to a linear regression, the slope of which was defined as the stiffness of tendon structures. Knee and ankle angles at contact during running were determined at a speed of 18 km/h on a treadmill. Knee and ankle angles at contact were not correlated to the stiffness of tendon structures in knee extensors and plantar flexors. In addition, the best official record in a 5000-m race was not significantly correlated to knee and ankle joint angles at contact. In conclusion, knee and ankle angles at contact were not related to the elastic properties of tendon structures in knee extensors and plantar flexor and the performance of long distance running.