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11.
Heikki Rusko 《Journal of sports sciences》2013,31(3):273-286
The influences of growth, training and various training methods were investigated by analysing long‐term training effects in young cross‐country and biathlon skiers (n = 129). Some athletes (n = 49) were studied six times in three years and some at least once a year during a four year period (n = 48). During three summer training periods skiers emphasized either intensive training or distance training or continued to train normally. The results indicated that maximal oxygen uptake (VO2 max) and heart volume increased between 15 and 20 years of age and the most significant changes in heart volume were observed between 16 and 18 years of age. International level skiers were able to increase their VO2 max and heart volume even after 20 years of age. Anaerobic threshold (AT, ml kg‐1 min‐1) increased like VO2 max but when expressed as a percentage of VO2 max, the AT was similar in every age group over 16 years of age. Intensive training at the intensity of anaerobic threshold or higher was observed to be most effective in producing improvements in VO2 max. Low‐intensity distance training was more effective in producing improvements in anaerobic threshold. 相似文献
12.
Puolakanaho A Poikkeus AM Ahonen T Tolvanen A Lyytinen H 《Journal of learning disabilities》2003,36(5):416-423
Four computer-animated tasks were created to analyze the underlying structure of emerging phonological awareness at 3.5 years of age and to explore the factors that influence children's (N = 91) performance on the tasks. Our findings indicated that already at this young age, children are able to master tasks demanding identification, blending, and continuation of phonological units when the tasks are presented in a motivating assessment context. In line with earlier research, children showed higher mastery in dealing with words and syllables than in dealing with phonemes. Targets in the initial position of a word were easier for children to identify than those in the final position. Our analysis provided support for two major dimensions of emerging phonological awareness based on the cognitive operations of the tasks: identification and blending of phonological units. 相似文献
13.
Longitudinal predictors of reading and spelling across languages varying in orthographic consistency
George K. Georgiou Minna Torppa George Manolitsis Heikki Lyytinen Rauno Parrila 《Reading and writing》2012,25(2):321-346
We examined the longitudinal predictors of nonword decoding, reading fluency, and spelling in three languages that vary in
orthographic depth: Finnish, Greek, and English. Eighty-two English-speaking, 70 Greek, and 88 Finnish children were followed
from the age of 5.5 years old until Grade 2. Prior to any reading instruction, they were administered measures of phonological
awareness, letter knowledge, and rapid naming speed. In Grade 2, they were administered measures of nonword decoding, text-reading
fluency, and spelling. The results showed that the model for nonword decoding in Greek was similar to that of Finnish (both
have consistent grapheme-to-phoneme mappings) while the model for spelling in Greek was similar to that of English (both have
some inconsistent phoneme-to-grapheme mappings). In addition, the models for nonword decoding and spelling in Finnish were
similar, because Finnish is consistent in both directions. Letter knowledge dominated the prediction in each language. The
predictable role of orthographic consistency on literacy acquisition is discussed. 相似文献
14.
The aim of this study was to compare the 'anaerobic threshold' (AnT) of subjects determined during a continuous 2-min incremental exercise test until exhaustion and the 'maximal lactate steady-state' (BLaSsmax) determined during prolonged exercise at constant loads corresponding to the subjects' AnT and/or 5-25% above and below it. Seventeen subjects performed an incremental exercise test and 1-5 prolonged exercise tests on a cycle ergometer until exhaustion at intervals of 1 week, and work rates, oxygen uptake (VO2) values and brachial venous blood lactate (BLa) levels were measured. It was proposed that when exercising at a constant workload below AnT, BLa would fall after having reached its peak; at the level of AnT, BLa reaches maximal steady-state (BLaSsmax); and above AnT, BLa increases continuously. Altogether, in 34 of 45 tests with a constant workload between 80 and 125% AnT, BLa values were as expected. In those cases in which BLaSsmax was reached, BLa increased on average by 3.8 mM from resting levels. This increase was 2.0 mM greater than that seen between resting levels and AnT during incremental exercise. There was no correlation between BLa values at BLaSsmax and at AnT, both when expressed as an increase in BLa (delta BLa) and absolute BLa concentration. Altogether, 81% of the variation in BLa concentration at BLaSsmax could be explained by the subjects' age, the percentage of slow-twitch fibres and BLa levels at rest. The AnT and BLaSsmax did not differ significantly, and these values were correlated (r = 0.83). Together, AnT and age accounted for 85% of the variation seen in BLaSsmax. The BLaSsmax did not correlate with AnT when fixed at a BLa concentration of 4 mM (AnT4mM). The three hypotheses tested in this study were confirmed, and the present results demonstrate that AnT correlates with BLaSsmax. The few exceptions to anticipated BLa kinetics were small in magnitude and could be explained by physiological variations. 相似文献
15.
Konttinen N Mets T Lyytinen H Paananen M 《Research quarterly for exercise and sport》2003,74(4):395-400
This study investigated the timing of the trigger pull in relation to the cardiac cycle during air rifle shooting. Electrocardiogram) was recorded from 20 male nonelite rifle shooters in two separate testing sessions. The testing was conducted at an indoor shooting range using an optoelectronic shooting system. Each participant fired a shot in the standing position at a distance of 10 m from the target. The results showed that compared to random triggering, the shooters fired more often during the phase of 10-50% of the R wave-to-R wave (R-R) interval and less often during the phase of 50-90%. With regard to performance accuracy, the participants exhibited average or above average performance, when the shot occurred in the beginning (0-50%) and in the end (70-99%) of the R-R interval. The less optimal range for the triggering was located within the 50-70% phase of the R-R interval. The length of R-R interval (i.e., heart rate) did not affect the relation of shot placement within the cardiac cycle to the accuracy of shooting performance. The present results extend previous findings by showing that in air rile shooting the optimum firing time within the cardiac cycle may be located in the systolic phase. It is argued that the systole-diastole dichotomy is not a sufficiently accurate way to investigate the effects of shot placement in the cardiac cycle. Further research is needed to examine the extent to which the relationship between the timing of triggering within the cardiac cycle and shooting performance depends a shooter's skill level. 相似文献
16.
Turid Hedlund Eija Airio Heikki Keskustalo Raija Lehtokangas Ari Pirkola Kalervo Järvelin 《Information Retrieval》2004,7(1-2):99-119
In this study the basic framework and performance analysis results are presented for the three year long development process of the dictionary-based UTACLIR system. The tests expand from bilingual CLIR for three language pairs Swedish, Finnish and German to English, to six language pairs, from English to French, German, Spanish, Italian, Dutch and Finnish, and from bilingual to multilingual. In addition, transitive translation tests are reported. The development process of the UTACLIR query translation system will be regarded from the point of view of a learning process. The contribution of the individual components, the effectiveness of compound handling, proper name matching and structuring of queries are analyzed. The results and the fault analysis have been valuable in the development process. Overall the results indicate that the process is robust and can be extended to other languages. The individual effects of the different components are in general positive. However, performance also depends on the topic set and the number of compounds and proper names in the topic, and to some extent on the source and target language. The dictionaries used affect the performance significantly. 相似文献
17.
The Effects of Conjunction, Facet Structure, and Dictionary Combinations in Concept-Based Cross-Language Retrieval 总被引：1，自引：1，他引：0
The paper studies concept-based cross-language information retrieval (CLIR). The document collection was a subset of the TREC collection. The test requests were formed from TREC's health related topics. As translation dictionaries the study used a general dictionary and a domain-specific (=medical) dictionary. The effects of translation method, conjunction, and facet order on the effectiveness of concept-based cross-language queries were studied, and concept-based structuring of cross-language queries was compared to mechanical structuring based on the output of dictionaries. The performance of translated Finnish queries against English documents was compared to the performance of original English queries against the English documents, and the performance of different CLIR query types was compared with one another. No major difference was found between concept-based and mechanical structuring. The best translation method was a simultaneous look-up in the medical dictionary and the general dictionary, in which case cross-language queries performed as well as the original English queries. The results showed that especially at high exhaustivity (the number of mutually restrictive concepts in a request) levels cross-language queries perform well in relation to monolingual queries. This suggests that conjunction disambiguates cross-language queries. An extensive study was made of the relative importance of the concepts of requests. On the basis of the classification data of request concepts it was shown how the order of facets in a query affects cross-language as well as monolingual queries. 相似文献
18.
Acclimatization to altitude and normoxic training improve 400-m running performance at sea level 总被引：2，自引：0，他引：2
To investigate the benefits of 'living high and training low' on anaerobic performance at sea level, eight 400-m runners lived for 10 days in normobaric hypoxia in an altitude house (oxygen content = 15.8%) and trained outdoors in ambient normoxia at sea level. A maximal anaerobic running test and 400-m race were performed before and within 1 week of living in the altitude house to determine the maximum speed and the speeds at different submaximal blood lactate concentrations (3, 5, 7, 10 and 13 mmol x l(-1)) and 400-m race time. At the same time, ten 400-m runners lived and trained at sea level and were subjected to identical test procedures. Multivariate analysis of variance indicated that the altitude house group but not the sea-level group improved their 400-m race time during the experimental period (P < 0.05). The speeds at blood lactate concentrations of 5-13 mmol x l(-1) tended to increase in the altitude house group but the response was significant only at 5 and 7 mmol x l(-1) (P < 0.05). Furthermore, resting blood pH was increased in six of the eight altitude house athletes from 0.003 to 0.067 pH unit (P < 0.05). The results of this study demonstrate improved 400-m performance after 10 days of living in normobaric hypoxia and training at sea level. Furthermore, the present study provides evidence that changes in the acid-base balance and lactate metabolism might be responsible for the improvement in sprint performance. 相似文献
19.
The play and language behavior of mothers with (n = 49) and without (n = 49) specific reading disabilities (RD) was investigated during play with their 14-month-old children. The contribution of maternal behavior to the language development of their children was examined. The children's receptive and expressive language skills were assessed longitudinally at 14, 18, and 30 months, using the MacArthur Communicative Development Inventories and the Reynell Developmental Language Scales. Children with and without familial risk for RD did not differ from each other in any play or language measures at these ages. No group differences were found for mothers' manifestations of nonsymbolic play and language. However, the typically reading (TR) mothers produced significantly more symbolic play and language in play interactions with their child than did the mothers with RD. The correspondence between mother-child symbolic play and maternal play-related language was also higher for the TR group than it was for the RD group. The mothers' symbolic play did not show any relation to their children's language development, but their expressions of symbolic language did show a relationship. The mothers' child-directed symbolic language contributed significantly toward the comprehension skills of 14- and 18-month-olds in the RD group. This association, however, was lower at 30 months, at which point it was reliably present for the first time in the TR group. 相似文献
20.
Emerging phonological awareness was compared in two groups of 3.5-year-old children belonging to the Jyv?skyl? Longitudinal Study of Dyslexia (JLD): children with familial risk of dyslexia (at-risk group n = 98) and children without such risk (control group n = 91). Four computer animated tasks were used: Word-level and Syllable-level Segment Identification, Synthesis, and Continuation of Phonological Units. The control group children manifested higher mastery than children in the at-risk group in phonological awareness, and the proportion of children with a low phonological awareness mean score was 2.5 times higher in the at-risk group than in the control group. In both groups, phonological awareness at 3.5 years was predicted by early language skills assessed between 14 and 26 months of age, and it was also associated with concurrent language. The difference between the at-risk and control group at 3.5-year in phonological awareness remained significant, even when the effect of other language skills such as productive and receptive vocabulary, and mastery of inflections, measured both at earlier ages and concurrently were controlled for. Our findings indicate that familial risk for dyslexia is reliably reflected in emerging phonological awareness already at this early age and it can be assessed independently of other language skills. 相似文献