Flat Running Research Articles

Europe has the fastest Ironman race courses and the fastest Ironman age group triathletes

The majority of participants in Ironman triathlon races are age group athletes. We have extensive knowledge about recreational athletes’ training and competition participation. Nonetheless, Ironman age group triathletes must achieve fast race times to qualify for the Ironman World Championship in Hawaii. They can, therefore, benefit from knowing where the fastest Ironman racecourses in the world are. The aim of the present study was to investigate where the fastest Ironman racecourses for age group triathletes are located in the world. Data from 677,702 Ironman age group finishers’ records (544,963 from men and 132,739 from women) originating from 228 countries and participating in 444 events across 66 different Ironman race locations between 2002 and 2022 were analyzed. Data was analyzed through traditional descriptive statistics and with machine learning regression models. Four algorithms were tested (Random Forest Regressor, XG Boost Regressor, Cat Boot Regressor, and Decision Tree Regressor). The models used gender, age group, country of origin, environmental factors (average air and water temperatures), and the event location as independent variables to predict the final overall race time. Despite the majority of successful Ironman age group triathletes originating from the USA (274,553), followed by athletes from the United Kingdom (55,410) and Canada (38,264), these countries exhibited average overall race times that were significantly slower compared to the fastest countries. Most of the triathletes competed in Ironman Wisconsin (38,545), followed by Ironman Florida (38,157) and Ironman Lake Placid (34,341). The fastest overall race times were achieved in Ironman Copenhagen (11.68 ± 1.38 h), followed by Ironman Hawaii (11.72 ± 1.86 h), Ironman Barcelona (11.78 ± 1.43 h), Ironman Florianópolis (11.80 ± 1.52 h), Ironman Frankfurt (12.03 ± 1.38 h) and Ironman Kalmar (12.08 ± 1.47 h). The fastest athletes originated from Belgium (11.48 ± 1.47 h), followed by athletes from Denmark (11.59 ± 1.40 h), Switzerland (11.62 ± 1.49 h), Austria (11.68 ± 1.50), Finland (11.68 ± 1.40 h) and Germany (11.74 ± 15.1 h). Flat running and cycling courses were associated with faster overall race times. Three of the predictive models identified the ‘country’ and ‘age group’ variables as the most important predictors. Environmental characteristics showed the lowest influence regarding the other variables. The origin of the athlete was the most predictive variable whereas environmental characteristics showed the lowest influence. Flat cycling and flat running courses were associated with faster overall race times. The fastest overall race times were achieved mainly in European races such as Ironman Copenhagen, Ironman Hawaii, Ironman Barcelona, Ironman Florianópolis, Ironman Frankfurt and Ironman Kalmar. The fastest triathletes originated from European countries such as Belgium, Denmark, Switzerland, Austria, Finland, and Germany.

The impact of physique on strategy and performance in the 400 m hurdles race among elite male athletes

Introduction: the objective of this study was to assess the impact of physique on the stride pattern and performance of elite male 400-m hurdles runners. Materials and Methods: this study is based on the analysis of the performance of 297 male 400-m hurdlers in 13 Olympic games, 16 world championships, and 15 European championships. The hurdlers were divided into 4 groups, based on their height and body mass index (BMI) – taller and heavier (TH), taller and lighter (TL), shorter and heavier (SH), and shorter and lighter (SL). Times taken to complete various phases of the 400-m hurdles race – H0-1 (from starting line to hurdle 1), H1-3 (from hurdle 1 to hurdle 3), H3-5, H6-8, H8-10, and H10-F (from hurdle 10 to the finishing line) – were noted. Similarly, the number of strides to complete 3 inter-hurdle phases (H1-4, H4-7, and H7-10) was recorded. Results: The technical index (TI = time for 400m hurdles run – time for 400m flat run) was the lowest in TH, followed by TL, SL, and SH. The stride number increased from H1-4 to H7-10. Taller hurdlers took fewer strides than shorter ones. Only 8.5% of the hurdlers followed a uniform stride number (13 or 15). Conclusions: the physique of elite 400-m men hurdlers can vary widely. Taller hurdlers fly over hurdles more efficiently; a uniform stride pattern is independent of height and BMI, and is followed by a few hurdlers only, and physique has a significant impact on running performance at a few phases of the 400-m hurdles run.

The Effect of Bodyweight Support and Incline Running on Triceps Surae Electromyographic Activity

Body weight support (BWS) and incline running (IR) are commonly used either during rehabilitation or during training separately, with many positive effects on athletes’ performance and rehabilitation. The aim of the present study was to investigate the interaction between bodyweight support and incline running on the electromyographic activity of the triceps surae and compare it to flat running. In eighteen healthy men (age: 20.3 ± 1.2 years, body weight: 70.2 ± 4.8 kg, body height: 179.6 ± 5.4 cm), the changes in electromyographic activity (EMGA) during a 10 min run with BWS (15% or 30% of body weight; in different occasions) and IR at 7%, as well as jumping performance and gait spatiotemporal parameters, were evaluated. A lower Rating of Perceived Exertion and a significant decrease in the size of the Vastus Lateralis (VL) (33.4%), Soleus (SOL) (17%), and Gastrocnemius Lateralis (GL) EMGA (28.5%, p < 0.05) but not in Gastrocnemius Medialis (GM) (10.5%, p > 0.05), was observed during BWS30% at 7% slope compared to flat running. Also, low-frequency fatigue of the quadriceps was induced only after running without BWS on a 7% slope (p = 0.011). No changes were found in jumping performance (p = 0.246) and gait spatiotemporal parameters (p > 0.05) except for flight time (p < 0.006). In conclusion, running with a slope of 7% and 30% of BWS can result in EMG activity comparable to that observed during level running. This method can also be used in prevention and rehabilitation training programs without creating fatigue.

Effect of Flat Running Shoes on Hip Kinematics in Male Recreational Runners.

Patellofemoral joint pain and iliotibial band syndrome are very common running-related injuries. Excessive contralateral pelvic drop, hip adduction, and hip internal rotation have been suggested to be associated with the two injuries. The purpose of this repeated measures and the cross-sectional study was to investigate the effect of flat running shoes on these kinematic variables compared with that of conventional running shoes with a 10 mm drop. Eighteen male recreational runners were recruited to run in flat shoes and conventional shoes with a 10 mm drop, in random order. Impact force data and lower extremity kinematics were synchronously obtained using two Kistler force plates and eight motion infrared cameras, whereas differences in the impact force and hip kinematics were compared using statistical parametric mapping. Regarding hip kinematics, the hip flexion (p = 0.004) and adduction angles (p = 0.004) decreased significantly at 30-70% and 62-85% of the stance phase, respectively, while wearing flat running shoes; the contralateral pelvic drop angle (p = 0.001) decreased significantly at 31-75% of the stance phase while wearing flat running shoes. The knee internal rotation angle (p = 0.035) decreased significantly at 8-17% of the stance phase while wearing flat running shoes compared with conventional running shoes. Given that these kinematic variables are associated with patellofemoral joint pain and iliotibial band syndrome, flat running shoes may have potential benefits for the prevention or treatment of knee injuries.

Analysis of IR Drop, Signal Electromigration and Self-Heating Effect using Flat and Hierarchical Method in FinFET Technology

VLSI industry has been rapidly growing where multiple processors can be implemented on a single chip. In physical design of a chip main factors to be considered are timing closure, congestion, and power. Compare to 180nm and 90nm designs were not much complicated due to less transistor density as going to lower technology nodes chip size, area, length will decrease that impact on packaging and cooling issues, so it is necessary to estimate the power at the early stage of design. Power analysis is done immediately after placement and routing stage of the chip. Power analysis can be performed in two methods one is flat method and other is hierarchical method. In flat method of analysis, the data of both top level and block level is given as input data to calculate the results whereas in hierarchical method of analysis the Power Grid View (PGV) of hierarchical block is designed which is then given as input. In hierarchical runs the sub-blocks are black boxed. The simulation is carried out using the Voltus IC Integrity Solution tool from cadence for a chip designed in 16nm FinFET technology. The results obtained from the flat method of analysis takes 2X the runtime compared to hierarchical method which would be unfavorable for very much larger circuits. The IR drop in VDD and VSS are 11.69 mW and 11.02mW respectively in flat method and 12.32 mW and 13.26 mW for VDD and VSS in hierarchical method of analysis. The accuracy is more obtained in flat run due to its transparency in logic functions.

The percentage of recreational runners that might benefit from new running shoes. A likely scenario

Knowing how many people are likely to benefit from a newly developed running shoe is of high relevance for footwear developers, phrasing legal claims and ultimately purchasing consumers. In order to assess and evaluate a likely scenario, the between-days reproducibility of percentages benefitting from lighter conventional flat running shoes (CON) or lighter advanced shoes with high stack height and longitudinally placed stiffening element (ADV) was investigated in a pool of 32 recreational runners. After comparing ADV and CON against running in heavier familiar shoes (OWN), percentages of the participant pool benefitting at different magnitudes of metabolic saving were derived. When comparing percentages of participants benefitting from CON and ADV between visits, retest correlation coefficients were respectively 0.95 and 0.99. Across magnitudes, the typical errors of percentages benefitting were 9.18% (CON) and 3.46% (ADV). Stated group averages of i.e. 4% metabolic savings when running in ADV, may potentially lead to the false assumption that the stated benefit applies to every runner. In contrast, based on our introduced approach, one can reliably state that a metabolic saving of i.e. 4% can be expected for at least 25% of recreational runners. Therefore, the expected percentage population benefitting at given magnitudes might be a more transparent expression for developers, marketing teams and consumers considering the relatively large measurement error of footwear induced metabolic savings on individual level.

Specification of estimation of a passenger car ride smoothness under various exploitation conditions

The stability and smoothness of rolling stock running could be defined accurately by universal Sperling's comfort index. The divergences of variation of Sperling's comfort index of a passenger car under specific operating conditions of running gear are examining in this paper. Numerical simulations of a passenger car running with independently rotating wheels under various conditions have been performing. Gained results showed that divergences of the Sperling's comfort index variation are particularly significant due to running gear component oscillations in the horizontal plane (lateral direction). A field experiment of a passenger car with a solid (traditional) wheelset with a flat running surface proved this hypothesis. The obtained results of this experiment confirmed this assumption. Therefore, the study of the regularities of lateral oscillations of a passenger car is the logical direction of further research.

Impact of Acute Eccentric versus Concentric Running on Exercise-Induced Fat Oxidation and Postexercise Physical Activity in Untrained Men

Introduction This study aimed at comparing the rate of exercise-induced fat oxidation and postexercise free-living physical activity after constant-load flat running (FR) and downhill running (DHR) bouts at an intensity that elicited maximal fat oxidation. Methods Participants were 11 healthy untrained men (mean age 25.6 ± 3.3 years; VO2max39.11 ± 8.05 ml/kg/min). The study included four visits. The first two visits determined the intensity of maximal fat oxidation during incremental FR and DHR tests. The second two visits involved constant-load FR or DHR at the intensity that elicited maximal fat oxidation in a counterbalanced order separated by two weeks. Gas exchange analysis was used to measure substrate oxidation during all exercise sessions. Sedentary time and physical activity were measured using ActiGraph triaxial accelerometers for three days including the day of exercise tests (the second day). Results During the incremental exercise tests, fat oxidation was significantly greater during the first stage of FR (P < 0.05) but started to increase during the fourth stage of DHR, although this did not reach significance. Of the 11 participants, 7 had greater fat oxidation during DHR. During continuous constant-load running, fat oxidation was higher during DHR than FR but at only two stages was either significant or borderline significant, and the time/group interaction was not significant. There was no significant effect on sedentary time of time/group interaction (P = 0.769), but there was a significant effect of time (P = 0.005), and there was no significant effect on total physical activity of time/group interaction (P = 0.283) or time (P = 0.602). Conclusion Acute aerobic eccentric exercise at an intensity eliciting maximal fat oxidation enhanced exercise-induced fat oxidation without worsening postexercise free-living physical activity, indicating it could be a useful training modality in weight management programs.

Speed running is determined by strength and power in young football players

Introduction: For years researchers and trainers have been looking for determinants of sports talent in the youngest and also in the relationship between individual motor features relevant in given sport disciplines. There is a fundamental consensus in the opinion that the strength and power of the lower limbs are correlated with the speed of running. However, this relationship also among the youngest is not so clear. The purpose of the work was to show the relationship between strength and power generated during vertical jump and achieved height jump and the speed of flat running in the youngest footballers. Material and methods: The research covered 75 children training football at the age of 6–14 years divided into two age groups. The subjects made a countermovement jump on a dynamometric platform measuring strength, power, speed of rebound and the height obtained, after which they performed a flying run over a distance of 20 m. Results: A strong, positive correlation was demonstrated between all dynamic and kinetic parameters of the jump and running speed. This correlation turned out to be clearly stronger in the older group of football players than in the younger group. Conclusions: The obtained results suggest that strength and power are good predictors, such an important feature in football as the player’s motion speed, already at the basic level of training.

Wait for Me

Wait for Me Katey Schultz (bio) Click for larger view View full resolution Photo by Jeff Turner Every day, I stepped off the school bus on Flat Run Road, and every day, on the other side of the fence, Judy Puckett sat astride a four-wheeler, gunning the engine. “Sarvis Morton, you’re dumber than a dummy!” she’d shout, then tear into the pasture, over the hill, and through the coal chute. We lived in Pentress, [End Page 91] seventeen miles from Morgantown, and even with the sock factory and a post office with Wi-Fi, Pentress was easy to miss. But Judy never missed the sad exhalation of the school bus, or me, abandoned along the roadside after it wheeled away. I had about fifteen seconds between insults while Judy took the four-wheeler through obstacles. I learned to walk fast. On a good day, I could be out of earshot after just four or five of her assaults. But sometimes the wind slowed me down. Or mud. The ditch along Flat Run Road was steep, and I’d fallen in once. “Sarvis Morton, your brother’s a retard, and so’re you!” “Sarvis Morton, if you had another brain, it’d be lonely!” I’d have settled for giving her a nasty look, but she already had one— pug nose that flared when she yelled, voice pitched like a pack of coyotes. Dirty brown hair like bitterroot vines slapping across her face and a neon tube top paired with whatever jeans her older sisters had worn the year before. I couldn’t cross the road because Old Man Mooney’s pit bull lived on the other side. It doesn’t take being on honor roll to know a chain only puts the inevitable on hold. When a pit wants something, it’ll get it. If that means breaking a chain or breaking skin, that’s what it means. “I didn’t ask for your opinion,” I’d shout back. “Earth is full. Go home!” But rain, scalding sunshine, sideways wind—Judy came at me. She never could have gotten to me—not with that ten-foot pole fence between us, barbed wire rimming the top. Still, I felt more intimidated by her than by the punks at school. The way her biceps flexed when she steered, rounded and limber arms framing her rib-thin torso. The neon tube top unnerved me. Like she couldn’t be bothered to get dressed all the way, or like nobody she lived with cared. I guess that’s what it came down to. Nobody did care. Not as far as I could tell. “Sarvis Morton . . .” “Sarvis Morton . . .” ________ As the crow flies, my house wasn’t far from a wildlife management area. We just called it “the lake,” because that was the only reason anyone would ever go. The foothills boasted hundreds of acres of mixed hard-wood, but all I’d ever seen of West Virginia was trees or the tops of mountains where trees used to live. More trees didn’t particularly excite me. A lake, however, was something special. Flush or poor—Morgantown [End Page 92] or Pentress—everybody loved a good swim in summertime. Even Judy Puckett. Judy had been giving me hell ever since I’d seen her at the lake, her older sisters ripping her tube top off and laughing. They had her outnumbered at the end of a dock that jutted into a deep, narrow finger of the water. I watched from the opposite shore just twenty feet away. The tube top came off fast—the tallest sister holding Judy in a full nelson while another pulled it down her waist and past her knees, throwing it into the water like a piece of trash. If that had been me, I’d have jumped into the water as soon as I got free. But when the tall one released her, Judy turned around and knuckle-punched her in the throat. The other sister got worked up then, and two more sisters came dashing down the dock, strutting in their bikinis and raising their fists, and it was only then—outnumbered by her own...

Topographic Effects on the Luzon Diurnal Cycle during the BSISO

AbstractCloud-resolving simulations are used to evaluate the importance of topography to the diurnal cycle (DC) of precipitation (DCP) over Luzon, Philippines, and surrounding ocean during the July–August 2016 boreal summer intraseasonal oscillation (BSISO) event. Composites of surface precipitation for each 30-min time increment during the day are made to determine the mean DCP. The mean DCP is computed separately for suppressed and active BSISO conditions and compared across three simulations with varying topography—flat, true, and doubled topographic height. The magnitude of the topographic height helps to dictate the timing, intensity, and location of diurnal precipitation over and near Luzon. For example, the mean DCP in the true topography run peaks 1.5 h later, is broader by 1 h, and has a 9% larger amplitude during active conditions relative to suppressed conditions. By contrast, the flat run mean DCP is earlier and narrower by 0.5 h with a 5% smaller amplitude during active conditions versus suppressed conditions. Within the suppressed or active BSISO conditions, the mean DCP peak and amplitude increase as the topographic height increases. The presence of elevated topography focuses precipitation over the coastal mountains during suppressed conditions, while dictating which side of the domain (i.e., east Luzon and the Philippine Sea vs west Luzon and the South China Sea) more precipitation occurs in during active conditions. These topographic-induced changes are discussed in terms of mechanical and thermodynamic forcing differences between the two large-scale BSISO regimes for the three runs.

Meiofauna and nematode community assemblage as sediment disturbance indicator in Mida Creek, Kenya

Abstract. Wafula M, Muthumbi A, Wang’ondu V. 2019. Meiofauna and nematode community assemblage as sediment disturbance indicator in Mida Creek, Kenya. Ocean Life 3: 24-37. Meiofauna is a group of benthic fauna mostly found in the sediments’ upper centimeters (cm), including Copepoda, Polychaeta, and Nematoda. This study focused on determining nematodes’ potential as bio-indicators of sediment disturbance caused by bait harvesting. Furthermore, bait harvesting was common, albeit with different intensities, on the different beaches of Mida Creek, Kenya, on November 2013. Sediment samples were collected along two transects within the mud flat running from the mangrove forest edge to the edge of the subtidal zone. Along the transects, 1 m² was placed at 20 m intervals. A replicate of 2 sediments core (3.4 cm diameter, 10 cm deep) was taken from each quadrat. Next, samples were fixed using 5% formalin, stored in plastic bottles, and then transported to the laboratory for processing and identification. The nematodes were used because it could bring out a clear difference in their distribution, community assemblage, diversity, and abundance due to sediment disturbance compared to other meiofauna. Of the total meiofauna, 3,988 individual nematodes were identified to the genus level. In addition, Nematoda was the most abundant taxon of all other meiofauna taxa. The bait harvesting through digging was more pronounced in Mayonda due to its wider mud flat width. The result showed a clear difference in the distribution, diversity, and community assemblage of the nematodes seen in all the sites. A sum of 83 nematode genera was encountered in Mida Creek. Kirepwe had 58 genera, Dabaso had 46 and Mayonda had 35. Mayonda had the highest nematode diversity, then followed by Kirepwe and Dabaso. On the contrary, Dabaso had the highest nematode density, then followed by Mayonda and Kirepwe. The meiofauna had a high community similarity, while nematode community similarity was lower at different levels of sediment disturbances. That makes the nematodes better bio-indicators as compared to meiofauna as a group. Therefore, this study points out that digging out polychaetes causes sediment disturbance. The disturbance affects the benthic fauna distribution, community assemblage, diversity, and abundance. Moreover, Terschellingia and Spirinia were distributed across all sites, even though in disturbed quadrats the numbers reduced significantly. On the contrary in disturbed quadrats, Viscosia, Pontonema, Synochium, Haliplectus, and Pheronus increased in numbers. To measures such as educating the fishermen on the effects of digging polychaete should be emphasized to safeguard marine biodiversity and its ecosystem.

Joint Moment Contributions During Flat, Incline and Decline Running in Individuals with ACLR

PURPOSE: To compare ankle, knee and hip joint moment contributions during flat, incline and decline running between limbs in ACLR individuals. METHODS: 9 participants (4 males, 5 females, mean age 22 ± 2yrs) provided consent to participate. Participants ran during flat (0°), incline (10°) and decline (-10°) treadmill conditions, with predetermined speeds of 2.5m/s (0°) and 1.8m/s (10° and -10°). Kinematic and kinetic data were collected during the final 30s of each condition using 17 cameras (Vicon) and an instrumented split-belt treadmill (Bertec). Joint moment contribution percentages at the hip, knee and ankle were determined by dividing the peak, sagittal, external joint moments (N.mm/kg) by the sum of all three joint moments during stance. A 2x3 (limb x condition) ANOVA was used to evaluate interlimb differences across conditions with post-hoc Bonferroni adjustments. RESULTS: There was no significant limb x condition interaction or main effect of limb, but there was a significant main effect of condition. Knee joint moment contributions were 35% greater in decline running when compared to incline running (50-15%), and 31% greater when compared to flat running (50-19%). Ankle contributions were 39% less in decline running when compared to incline running (24-63%) and 26% less in decline running when compared to flat running (24-50%). CONCLUSIONS: Knee and ankle joint moment contributions are altered with flat, incline, and decline running in persons with ACLR. Individuals with ACLR did not display asymmetries in joint moment contributions between the involved and uninvolved limb.

Validation of Garmin Fitness Tracker Biomechanics

Purpose: As fitness trackers become more available, the need for independent validation has become more important to drive accuracy in training decisions and physiologic research. THEREFORE, the purpose of this study was to find the reliability and accuracy of the data collected from the Garmin fenix 3 HR fitness tracker. METHODS:17 healthy, recreational runners (9 male, 8 female, 28.11 ± 7.38 yrs, 70.26 ± 10.76 kg, 173.77 ± 5.96 cm) performed three running conditions (flat, incline (5%), and decline (-5%)) on an instrumented treadmill used to collect ground reaction force data. Infrared markers were placed on the foot and trunk and tracked with a 16 camera motion capture system. The data was processed using Visual 3D software (5.0, C-Motion, Inc., Germantown, MD,USA) and variables extracted were compared to data collected by the Garmin fenix 3 HR (Garmin Ltd., Olathe KS). RESULTS: Statistical analysis was done via a 2-tailed paired t-test comparing the data taken from the motion capture system and instrumented treadmill to the data collected by the Garmin watch. There were no differences between the Garmin and the treadmill for flat stride length, declined stride length, inclined run cadence, declined run cadence, and inclined ground contact time. Differences (p < 0.05) were observed in inclined stride length, flat run cadence, flat vertical oscillation, inclined vertical oscillation, declined vertical oscillation, flat ground contact time, and declined ground contact time. CONCLUSION: Overall the Garmin fenix 3 HR fitness tracker was found to be reasonably reliable for certain variables, such as stride length and run cadence, but not reliable for vertical oscillation and ground contact time. Certain considerations should be taken as to the accuracy of the variables when using this data to drive training adaptations.

Effects of Acute Eccentric Exercise on Appetite-Related Hormones and Food Preferences in Men

Eccentric exercise has been suggested to improve muscle atrophy, muscle function, and insulin sensitivity. The aim of this study was to examine the effect of acute eccentric exercise on appetite-related hormones, food preferences, and food intake. Fourteen moderately active men were recruited to participate in this study (age 24.2 ± 5.5 years; BMI 23.4 ± 3.3 kg/m2; VO2max 48.9 ± 3.1 ml/kg/min). Three different conditions were implemented; no exercise, flat running “inclination 0” and downhill running “inclination –12%.” Appetite-related hormones, subjective appetite sensations, food preference and reward, and ad libitum food intake were measured at pre-, immediately post-, and 24 h post exercise. There were no significant median changes in total ghrelin or pancreatic peptide concentrations between conditions. There were also no median differences in subjective appetite ratings or energy intake between conditions, but the median change in explicit liking of sweet versus savory foods differed significantly between pre-exercise and 24 h post exercise (p = .013). Post-hoc analysis observed a significant difference in the pre-exercise to 24 h post exercise change between front running and downhill running (p = .023), and indicated greater liking of savory foods over sweet foods in downhill running than front running. However, no further differences were seen between conditions for the remaining food preference parameters, suggesting there were no systematic trends in these data. In conclusion, there was no effect of front and downhill running on eating behavior as compared to a nonexercise control condition, but these data need to be replicated in a larger and more heterogeneous sample.

PO-228 Effects of Different Cryotherapy Models on Timing Sequence Recovery of Exercise Induced Muscle Damage in Middle and Long Distance Runners

Objective Exercise induced muscle damage (EIMD) is one common physiological phenomenon in competitive sports and mass sports. Water immersion recovery and whole body cryotherapy (cryostimulation) (WBC) has become one of the fast recovery methods adopted by high level athletes in the world. The aim of this study was to compare the water immersion recovery and WBC from timing sequential recovery on EIMD, subjective scales, biochemical indicators, exercise performance indicators.&#x0D; Methods Twelve middle and long distance runners from Beijing Sport University were recruited in this study (exercise performance is secondary level in China). All participants performed four models in four weeks which included rest control (CON), cold water immersion(CWI), contrast water therapy (CWT) and whole body cryotherapy (cryostimulation) (WBC) separated by one week. The subjects needed to complete the EIMD exercise program, includes two parts: the treadmill running and the jump step. The individual speed of treadmill running was based on the individual VO2max. running including 5 sets and total time is about 90 min. Every set consist of 6 min flat running, 6 min uphill running and 6 min downhill running. The speed of the treadmill was stable in different stages. The slope of the uphill running is（＋6,＋5,＋4,＋3,＋2）, and the slope of downhill running is (-8, -7, -6, -5, -4). The jump was performed 20 times separated by 30 s via special step ( height is 40 cm) . After the EIMD exercise program, the subjects were treated with different recovery methods immediately after exercise, 24 h, 48 h, 72 h after exercise, while CON group received no intervention. The CWI group was immerged in 15 °C cold water for 12min, and the CWT groups was immerged in 15°C cold water for 1min and 38°C hot water for 1min with 6 cycles. The whole body cryotherapy (cryostimulation) group was immerged in special chamber (-110—-140℃）for 3 min. The three interventions were immerged body to the position of shoulders. The indexes including subjective scales (VAS scale, RPE scale, Borg scale, WHO deep sleep scale, PQSI scale), biochemical indicators (creatine kinase, lactate dehydrogenase, myoglobin, interleukin-6, C reactive protein, SICAM-1), exercise performance indicators ( vertical jump height, grip, running distance). The indexes was collected in different periods (i.e. Before exercise, immediately after exercise,Post1h, Post 24h, Post 48h, Post 72h, Post 96h after exercise etc.).&#x0D; Results (1) Subjective scales. From results of VAS scale, RPE scale, and Borg scale, the WBC had best recovery effects than the other three interventions (P&lt;0.05). The recovery effect of the CWI group was similar with the CON group. From results of WHO deep sleep scale and PQSI scale, the WBC group had better recovery effects than CON group (P&lt;0.05). (2) Biochemical indicators. From results of CK, Mb and SICAM-1, the WBC group had better recovery effect than the other three groups (P&lt;0.05). In the LDH, the WBC group had similar effects with the CWT group (P&gt;0.05). From results of CRP and IL-6, the WBC group had better recovery effects than the other three groups (P&lt;0.05).（3）Exercise performance indicators. From results of vertical jump, WBC had lower decrease than the other three groups (P&lt;0.05). From results of the grip, of the WBC and CWT groups have significant retentive effects than CON group (P&lt;0.05), but there was no significant difference between CON and CWI groups (P&gt;0.05).&#x0D; Conclusions (1)Through combine the treadmill running and the jump step exercise program,Can effectively lead to human body appear the EIMD. (2)WBC has positive effects on the subjective scale, biochemical indicators, exercise performance indicators associated with EIMD.For middle and long distance runners EIMD,compared with CWI CWT,WBC effect is better.(3) CWI and CWT has a positive effect on some subjective scales, biochemical indicators, and exercise performance indicators related to EIMD. However, the positive effect of CWI and CWT is lower than WBC in the extent of action and timing sequence. (4)For the middle and long distance runners EIMD timing sequence recovery effects,WBC have better effects,Followed by CWT , CWI effect is not significant.

The Effects of Specific Trainings Applied to 14 Age Male Soccer Players on Their Balance, Sprint and Technical Skills

The aim of this study was to investigate the effects of specific trainings applied to 14 age male soccer players on their balance, sprint and technical skills. 30 male soccer players, who attended the trainings at least 4 years in Çanakkale Beşiktaş Soccer School, joined to the study by having their parents confirm the “Parental Permission Form”. Soccer players mean of length was calculated 158.24±2.98 cm and mean of weight was calculated 46.37±3.44 kg. Soccer-specific trainings were applied to the players 12 weeks, 3 days a week, at least 90 minutes a day. Flamingo balance, 30 meters sprint and technical skill tests were applied before and after the training period. Datas were analyzed in statistic package programme by using “Paired t Test”. Results were evaluated according to “p&lt;0.05” significance level. Significant differences were found in comparing the tests’ results of soccer players (p&lt;0.05). As a result, it can be said that the inclusion of high-intensity deflection exercises instead of the high-rigidity, flat running conditions applied in soccer-specific training has improved the technical skills of 14-year-old footballers and additionally affects their balance and speed performance positively.

Effect of acute downhill running on bone markers in responders and non-responders.

The aim of the current study was to compare the effects of acute flat running (FR) and downhill running (DHR) on bone turnover markers in men. Fourteen healthy young active men performed three exercise tests in a counterbalanced order, including rest condition, FR, and DHR, at 60% maximal aerobic capacity on a treadmill with 0 and - 12% inclines. Blood samples were taken in the pre-exercise, immediately post-exercise, and 24-h post-exercise periods, and bone markers included total procollagen type 1 amino-terminal pro-peptide (total PINP) and N-MID osteocalcin. Total P1NP significantly increased after exercise independent of the form of muscle contraction (p > 0.05). N-MID osteocalcin increased after DHR by 17% compared to after pre-exercise, but the difference did not reach significance (p = 0.07; partial eta square, 0.21). Biomarker responses to exercise were dependent on the exercise form and independent of hormone type in half of the participants who were classified as responders. Physiological parameters and changes in muscle voluntary contraction did not explain the differences between responders and non-responders. The effect of acute DHR on bone turnover is determined by biomarker type and participant characteristics. Future studies should discriminate between the characteristics of responders and those of non-responders.

The efficacy of downhill running as a method to enhance running economy in trained distance runners

Running downhill, in comparison to running on the flat, appears to involve an exaggerated stretch-shortening cycle (SSC) due to greater impact loads and higher vertical velocity on landing, whilst also incurring a lower metabolic cost. Therefore, downhill running could facilitate higher volumes of training at higher speeds whilst performing an exaggerated SSC, potentially inducing favourable adaptations in running mechanics and running economy (RE). This investigation assessed the efficacy of a supplementary 8-week programme of downhill running as a means of enhancing RE in well-trained distance runners. Nineteen athletes completed supplementary downhill (−5% gradient; n = 10) or flat (n = 9) run training twice a week for 8 weeks within their habitual training. Participants trained at a standardised intensity based on the velocity of lactate turnpoint (vLTP), with training volume increased incrementally between weeks. Changes in energy cost of running (EC) and vLTP were assessed on both flat and downhill gradients, in addition to maximal oxygen uptake (⩒O2max). No changes in EC were observed during flat running following downhill (1.22 ± 0.09 vs 1.20 ± 0.07 Kcal kg−1 km−1, P = .41) or flat run training (1.21 ± 0.13 vs 1.19 ± 0.12 Kcal kg−1 km−1). Moreover, no changes in EC during downhill running were observed in either condition (P > .23). vLTP increased following both downhill (16.5 ± 0.7 vs 16.9 ± 0.6 km h−1,P = .05) and flat run training (16.9 ± 0.7 vs 17.2 ± 1.0 km h−1, P = .05), though no differences in responses were observed between groups (P = .53). Therefore, a short programme of supplementary downhill run training does not appear to enhance RE in already well-trained individuals.

평지와 경사 달리기 시 인체 운동사슬에 관한 역학적에너지 해석연구

The purpose of this study is to investigate the effects of lower limb and trunk segments on the flat and 5° slope running of male subjects in their early 20s. The kinematic variables of the lower limb and the trunk segment were investigated and the correlation between the two types of trunk model Ⅰ and trunk model Ⅱ was investigated. The following conclusions are obtained. First, there was a statistically significant difference in the leg joints in the weight-absorbed area according to inclination. Especially, the knee joints showed high level running and the hip joints showed high level of 5°slope running. Second, there was a difference in the inter pretation of the kinetic energy of the trunk generated by the trunk model two types. In the case of trunk model I, there was a statistically significant correlation between the trunk energy and the hip joint in the weight absorbing zone and the propulsive zone in the flat running. The 5°sploe running showed a significant correlation in the body weight absorbing zone. In case of trunk model Ⅱ, there was a statistically high correlation between the upper body of the torso and the knee joint in the flat running, and there was a significant correlation in the lower body of the torso and the knee joint in 5° slope running. From the above results, it is found that the hip and the knee joint affect the running exercise according to the inclination from the kinematic analysis of the upper body of the trunk and the lower extremity. Therefore, the upper and lower parts of the trunk should be strategically considered for efficiency and effectiveness in applying exercise techniques and training in hip joint and knee joints in terms of power output and energy efficiency.