Gait parameter changes during 10000 metre treadmill running

The purpose of this study was to measure the effects of fatigue on gait parameters during running. Research has shown that changes due to fatigue include those of step length, cadence, flight time, and joint angles. Thirteen male distance runners ran 10000 m at a pace equivalent to 103% of their personal best time. Kinetic data was collected using a Gaitway treadmill (1000 Hz), and kinematic data using two RedLake MotionPro high-speed cameras (250 Hz). Data was collected at five points. Repeated measures ANOVA showed that there were significant differences in maximum force, impulse, and contact time (p < .01). Dependent t-tests showed a significant difference for the knee angle at take-off (p < .01). The kinetic and temporal changes occurred as early as 3000 m. Athletes are recommended to race at a constant pace to reduce the effects of fatigue

The effects of fatigue on race walking technique

The purpose of this study was to measure the effects of fatigue on gait parameters during race walking. Research has shown that fatigued athletes require gait alterations in order to maintain speed. Eighteen competitive race walkers walked either 5 km or 10 km at a pace equivalent to 105% of their season’s best time. Junior athletes walked 5 km, while senior athletes (mostly 20 km walkers) walked 10 km. Kinetic data were collected using a Gaitway treadmill (1000 Hz). Data were collected at three points during the 5 km walks and at four points during the 10 km walks. Repeated measures ANOVA showed that there were significant differences in impulse and contact time parameters (p < .01). The kinetic and temporal changes occurred as early as 1 km. Athletes are recommended to race at a constant pace to reduce the effects of fatigue

The measurement of kinetic variables in race walking

The purpose of this study was to measure kinetic variables during race walking. Forty national and international race walkers walked either 5 km or 10 km at a pace equivalent to 105% of their season’s best time. Junior athletes walked 5 km, while senior athletes (mostly 20 km walkers) walked 10 km. Kinetic data were collected using a Gaitway treadmill (1000 Hz). Data were collected at the 2.5 km point. Men had longer step lengths than women and walked faster as a result. There was little difference in cadence. Average flight times for each group of athlete were approximately 0.04 s. Senior athletes showed more ‘typical’ race walking vertical force patterns than the juniors; this may be linked to quantity of training experience and gait efficiency. Athletes are advised to develop muscular strength endurance to cope with loading rates upon initial contact

Gait parameter differences between the legs during race walking

Prior research on the effects of fatigue during race walking has shown changes in step length and frequency (Knicker & Loch, 1990: New Studies in Athletics, 5, 25–38). It is unclear whether these changes are consistent for both legs. The purpose of the study was to investigate the differences between the legs for kinetic variables during race walking, and to measure changes occurring because of fatigue. The study was approved by the university’s ethics committee and informed consent was given by fourteen international race walkers, of whom four were females (age mean 28.2, s=7.4 years; stature 1.77, s=0.10 m; mass 66.0, s=11.7 kg). Each participant walked for 10 km on a treadmill (Gaitway, Traunstein). The average treadmill speed was 12.4 km h-1 (s=0.7) and each athlete walked at a constant pace. Data were recorded using the Gaitway treadmill, which has two in-dwelling force plates (Kistler, Winterthur). The sampling rate was 1000 Hz. Data were collected for 30 s at four times during the walk, at 2500 m, 4500 m, 6500 m and 8500 m. Statistical analysis consisted of repeated measures ANOVA. There was a significant difference between the legs for first peak force (F1,13=32.6, P¼0.001, Z2=0.71, power=0.99), weight acceptance rate (F1,13=14.5, P=.002, Z2=0.53, power=0.94), and push-off rate (F1,13=36.2, P=0.001, Z2=0.74, power=1), although these differences did not change significantly with distance walked. There was also a significant difference between the legs’ step lengths (F1,13=30.1, P=0.001, Z2=0.70, power=0.99), midsupport forces (F1,13=9.6, P=0.009, Z2=0.42, power=0.82), and propulsive force peaks (F1,13=20.6, P=0.001, Z2=0.61, power=0.99); the overall values for these variables also increased significantly with distance walked (P<0.001, P=0.009, and P<0.001 respectively). However, there was no effect of distance on the differences between the legs for any variable. The results show significant leg dominance during race walking. Athletes should be aware that these imbalances need rectification to prevent injury and maintain efficient walking technique. The imbalances did not appear to worsen with the onset of fatigue although this may occur over the longer championship distances of 20 and 50 km

Muscle activity of the stance knee in elite race walkers

The purpose of this study was to compare knee muscle activity in race walkers with different knee extension patterns. Three international athletes walked over two force plates recording at 1000 Hz. Video data were simultaneously recorded at 100 Hz; the digitised data were combined with the force data to calculate net muscle moments and joint powers. EMG testing was carried out on three muscles which cross the knee. The two walkers with legal techniques had similar moment and power patterns, whereas the non-legal walker experienced a longer period of eccentric flexor moment at the beginning of stance, which may have affected his ability to extend his knee correctly. After this, all three athletes experienced a period of isometric contraction at the knee. Achieving correct technique requires both strength endurance exercises and mobility development

Angular kinematics in elite race walking performance

The purpose of this study was to measure and analyse the important angular kinematic variables in elite race walking. Research has shown that these variables include knee angle at contact and midstance, rotation of the hips and shoulders, and hip extension velocity. Eighty elite race walkers were videoed during competition and analysed using 3D-DLT with SIMI Motion. The knee angle was found to be almost straight at contact in most athletes and hyperextended by the vertical upright position. Athletes varied in the amount of rotation at the hips and shoulders, with 50 km men having greater hip rotation and 20 km women having greater shoulder rotation. There was much more variation in the values found for elbow and shoulder angles. Very few angular measurements correlated with key race walking variables such as speed, step length and cadence

Valuing the attributes of renewable energy investments in Scotland

This study was funded by a grant from the Scottish Economic Policy Network (SEPN) with funding assistance provided by the University of Glasgow, Department of Economics (Professor Nick Hanley) and the University of Sterling (Robert Wright). The goal of the project was to determine the value of differing types of renewable energy projects by how they would effect environmental and community quality of life factors. The key issues examined include; air quality, landscape, wildlife, and long term local employment. Stated preference methods were employed through the use of a discrete choice experiment survey approach. Willingness-to-pay for different types of renewable energy projects was estimated, i.e., moderate onshore windmill farms, large onshore windmill farms, offshore windmill farms, and biomass fueled power plants. The most significant findings were that rural areas likely to be most highly impacted by the new energy projects were willing to accept low or moderate environmental damage in exchange for commercial development gains. Urban respondents on the other hand were more likely to oppose any disturbance to the landscape or wildlife and had no value placed on the economics development gains for the rural areas; income level of households showed no significant difference in environmental values

The effects of rent seeking over tradable pollution permits

The establishment of a tradable permit market requires the regulator to select a level of aggregate emissions and then distribute the associated permits (rent) to specific groups. In most circumstances, these decisions are often politically contentious and frequently influenced by rent seeking behaviour. In this paper, we use a contest model to analyse the effects of rent seeking effort when permits are freely distributed (grandfathered). Rent seeking behaviour can influence both the share of permits which an individual firm receives and also the total supply of permits. This latter impact depends on the responsiveness of the regulator to aggregate rent seeking effort. Using a three-stage game, we show that rent seeking can influence both the distribution of rents and the ex post value of these rents, whilst welfare usually decreases in the responsiveness of the regulator.tradable permit market, rent seeking, initial allocation

South American Coccinellidae (Coleoptera) : part 15, systematic revision of Dilatitibialis Duverger (Coccidulinae; Hyperaspidini)

Dilatitibialis Duverger (61 species) (Coleoptera: Coccinelidae: Coccidulinae; Hyperaspidini) is discussed, species described, illustrations provided, and a key to all recognized taxa included. Cleothera cognata Mulsant, Cleothera cruciferae Mulsant, Cleothera fuscomaculata Mulsant, Cleothera gaynoni Mulsant, Cleothera glyphica Mulsant, Cleothera jucunda Mulsant, Cleothera luteola Mulsant, Cleothera mulsanti Kirsch, Cleothera oseryi Mulsant, Cleothera poortmanni Mulsant, Cleothera scenica Mulsant, Cleothera semicincta Weise, Cleothera tropicalis Mulsant, Hinda guttipennis Weise, Hyperaspis carolinae Crotch, Hyperaspis ceciliae Crotch, Hyperaspis dilatata Crotch, Hyperaspis florifera Vogel, Hyperaspis gravabilis Brèthes, Hyperaspis hybridula Crotch, Hyperaspis laterinotata Brèthes, Hyperaspis silvani Crotch, and Hyperaspis suzannae Crotch are transferred to Dilatitibialis, becoming new combinations. Lectotypes are designated for D. boliviana, D. cognata, D. florifera, D. fuscomaculata, D. gaynoni, D. glyphica, D. gravabilis, D. guttipennis, D. luteola, D. jucunda, D. mulsanti. D. poortmanni, D. retigera, D. scenica, D. semicincta, and D. staudingeri. A total of 38 new species of Dilatitibialis are described: Dilatitibialis annie, D. carmen, D. cindy, D. connie, D. crystal, D. dawn, D. diana, D. edith, D. edna, D. elaine, D. ellen, D. emily, D. ethel, D. fallax, D. florence, D. gladys, D. grace, D. josephine, D. kim, D. lillian, D. lois, D. marjorie, D. norma, D. paula, D. peggy, D. phyllis, D. rita, D. robin, D. rosa, D. shannon, D. sheila, D. sherry, D. sylvia, D. thelma, D. tiffany, D. tina, D. tracy, and D. wendy. Corrections are made to titles of previous Parts of this series, as follows: South American Coccinellidae, Part XII (Gordon 2007) is changed to Part XIII; South American Coccinellidae, Part XII (Gordon et al. 2013) is changed to Part XIV

South American Coccinellidae (Coleoptera) : part 7, new name for Cyra Mulsant, review of Brachiacanthini genera, and systematic revision of Cleothera Mulsant, Hinda Mulsant and Serratitibia Gordon and Canepari, new genus

Genera of Brachiacanthini (Coleoptera: Coccinellidae: Hyperaspidinae) are discussed and a key to all recognized genera provided. Cyrea, new genus, is proposed, and Serratitibia, new genus, is erected and revised, Cleothera Mulsant and Hinda Mulsant are recognized as valid genera and revised. Helesius caseyi Sicard is transferred to Hinda and recognized as a synonym of Hinda designata Mulsant, new synonymy. Brachiacantha brethesi (Korschefsky), Cleothera abendrothi Kirsch, Cleothera ambigua Mulsant, Cleothera bisquatuorpustulata Mulsant, Cleothera decemsignata Mulsant, Cleothera gaillardi Mulsant, Cleothera humerata Mulsant, Cleothera tortuosa Mulsant, Cleothera traili Brèthes, Cleothera uncinata Mulsant, Hinda joeli Almeida and Milléo, Hinda modesta Weise, Hinda regularis Kirsch, Hyperaspis aliciae Crotch, and Hyperaspis fraudulenta Kirsch are transferred to Serratitibia, becoming new combinations. One new species of Hinda, H. ecuadorica, is described. A total of 73 new species of Serratitibia are described: Serratitibia amanda, S. andrea, S. angela, S. anna, S. ashley, S. barbara, S. barclayi, S. betty, S. beverly, S. bonnie, S. brenda, S. cheryl, S. christine, S. cynthia, S. debra, S. denise, S. donna, S. doris, S. elizabeth, S. evelyn, S. frances, S. gloria, S. heather, S. helen, S. irene, S. jacqueline, S. janet, S. janice, S. jean, S. jennifer, S. joan, S. joyce, S. judith, S. judy, S. julie, S. karen, S. katherine, S. kathleen, S. kathy, S. kelly, S. kimberly, S. laura, S. linda, S. lisa, S. loreto, S. lori, S. louise, S. margaret, S. marilyn, S. mary, S. martha, S. melissa, S. michelle, S. mildred, S. nancy, S. nicole, S. pamela, S. paprzycki, S. patricia, S. quincemil, S. rachel, S. rebecca, S. rose, S. ruby, S. ruth, S. sarah, S. satipoensis, S. shirley, S. stephanie, S. susan, S. tammy, S. teresa, and S. virginia. Lectotypes are here designated for Serratitibia lividipes, S. gaillardi, S. decemsignata, S. abendrothi, and S. ambigua