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The purpose of this study was to compare movement pattern, fatigue development, and heart rate (HR) for top-class elite female players when playing international (INT) vs. domestic league games (DOM). Video-based time-motion analyses and HR recordings were performed on 17 players during INT and DOM. The distances covered in high-intensity running (HIR) and sprinting were longer (p < 0.05) in INT compared with DOM. More (p < 0.05) HIR was covered in INT than DOM during first and second half. Additionally, more (p < 0.05) sprinting occurred in INT compared with DOM in the first half. In both game types, the amount of HIR was reduced by 24-27% (p < 0.05) in the last 15-minute period compared with the first four 15-minute periods of the game. The midfielders covered longer (p < 0.05) distances with HIR in INT than in DOM over the entire game and in the most intense 5-minute period of the games, whereas no differences were observed between the game types for defenders. No difference in the HR response was found between INT and DOM. In conclusion, more HIR and sprinting occur in international compared with domestic games, which may affect the fatigue development for players in physically demanding roles. Thus, our results are important to coaches to prepare players to meet the challenges of international soccer games and show that the ability to perform intense intermittent exercise should be trained regularly in elite female players. KEY WORDS match analysis, intermittent exercise, standard of play, fatigue

The purpose was to examine the fatigue pattern of elite female soccer players after competitive games. Soccer players (n = 23) from the Danish women Premier League performed a countermovement vertical jump test, a repeated 30-m sprint test, and the Yo-Yo intermittent endurance level 2 (Yo-Yo IE2) test at rested state and after a competitive game. Average heart rate during the game was 86 [+ or -] 1% of maximal heart rate with no differences between halves. Blood lactate was 5.1 [+ or -] 0.5 mmol*[L.sup.-1] after the first half, which was higher (p < 0.05) than after the second half (2.7 [+ or -] 0.4 mmol*[L.sup.-1]). Yo-Yo IE2 performance was 484 [+ or -] 50 m after the game, which was 62% lower (p < 0.05) than at rested state (1,265 [+ or -] 133 m). Average sprinting time of three 30-m sprints was 5.06 [+ or -] 0.06 seconds after the game, which was 4% slower (p < 0.05) than at rest (4.86 [+ or -] 0.06 seconds). No game-induced effect was observed on vertical jump performance. Significant inverse correlations were observed between Yo-Yo IE2 test performance and fatigue index during the repeated sprint test both at rest (r= -0.76, p < 0.05) and after the game (r = -0.66, p < 0.05). The study demonstrates that the type of fatigue that occurs after a female soccer game does cause marked impairment in intense intermittent exercise and repeated sprint performance but does not affect vertical jump performance. These findings support the notion that decrements in distance covered by sprinting and high-speed running toward the end of elite female games are caused by fatigue. KEY WORDS intermittent exercise performance, sprint, jump, blood lactate, football

We sought to study the physical demands and match performance of women soccer players. Nineteen top-class and 15 high-level players were individually videotaped in competitive matches, and time-motion analysis were performed. The players changed locomotor activity >1,300 times in a game corresponding to every ~4 seconds and covered 9-11 km in total. The topclass players ran 28% longer (P < 0.05) at high intensities than high-level players (1.68 [+ or -] 0.09 and 1.33 [+ or -] 0.10 km, respectively) and sprinted 24% longer (P < 0.05). The top-class group had a decrease (P < 0.05) of 25-57% in high intensity running in the final 15 minutes compared with the first four 15-minutes intervals, whereas the high-level group performed less (P < 0.05) high-intensity running in the last 15 minutes of each half in comparison with the 2 previous 15-minute periods in the respective half. Peak distance covered by high intensity running in a 5-minute interval was 33% longer (P < 0.05) for the top-class players than the high-level players. In the following 5 minutes immediately after the peak interval top-class players covered 17% less (P < 0.05) high-intensity running than the game average. Defenders performed fewer (P < 0.05) intervals of high-intensity running than midfielders and attackers, as well as fewer (P < 0.05) sprints than the attackers. In conclusion, for women soccer players (1) top-class international players perform more intervals of high-intensity running than elite players at a lower level, (2) fatigue develops temporarily during and towards the end of a game, and (3) defenders have lower work rates than midfielders and attackers. The difference in high-intensity running between the 2 levels demonstrates the importance of intense intermittent exercise for match performance in women soccer. Thus, these aspects should be trained intensively in women soccer. KEY WORDS time motion analysis, high-intensity intermittent exercise, fatigue, playing position, standard of play.

This study examined the effect of two different intense exercise training regimens on skeletal muscle ion transport systems, performance, and metabolic response to exercise. Thirteen subjects performed either sprint training [ST; 6-s sprints (n = 6)], or speed endurance training [SET; 30-s runs ~130% [Vo.sub.max], n = 7]. Training in the SET group provoked higher (P < 0.05) plasma [K.sup.+] levels and muscle lactate/[H.sup.+] accumulation. Only in the SET group was the amount of the [Na.sup.+]/[H.sup.+] exchanger isoform 1 (31%) and [Na.sup.+]-[K.sup.+]-ATPase isoform [[alpha].sub.2] (68%) elevated (P < 0.05) after training. Both groups had higher (P < 0.05) levels of [Na.sup.+]-[K.sup.+]-ATPase [[beta].sub.1]-isoform and monocarboxylate transporter 1 (MCT1), but no change in MCT4 and [Na.sup.+]-[K.sup.+] -ATPase [[alpha].sub.1] [[alpha].sub.1]-isoform. Both groups had greater (P < 0.05) accumulation of lactate during exhaustive exercise and higher (P < 0.05) rates of muscle lactate decrease after exercise. The ST group improved (P < 0.05) sprint performance, whereas the SET group elevated (P < 0.05) performance during exhaustive continuous treadmill running. Improvement in the Yo-Yo intermittent recovery test was larger (P < 0.05) in the SET than ST group (29% vs. 10%). Only the SET group had a decrease (P < 0.05) in fatigue index during a repeated sprint test. In conclusion, turnover of lactate/[H.sup.+] and [K.sup.+] in muscle during exercise does affect the adaptations of some but not all related muscle ion transport proteins with training. Adaptations with training do have an effect on the metabolic response to exercise and specific improvement in work capacity. muscle metabolites; [Na.sup.+]/[K.sup.+] pump; intermittent exercise performance; monocarboxylate transporter; [Na.sup.+]/[H.sup.+] exchanger

Interstitial [K.sup.+] ([[[K.sup.+]].sub.i]) was measured in human skeletal muscle by microdialysis during exhaustive leg exercise, with (AL) and without (L) previous intense arm exercise. In addition, the reproducibility of the [[[K.sup.+]].sub.i] determinations was examined. Possible microdialysis-induced rupture of the sarcolemma was assessed by measurement of carnosine in the dialysate, because carnosine is only expected to be found intracellularly. Changes in [[[K.sup.+]].sub.i] could be reproduced, when exhaustive leg exercise was performed on two different days, with a between-day difference of ~0.5 mM at rest and 1.5 mM at exhaustion. The time to exhaustion was shorter in AL than in L (2.7 [+ or -] 0.3 vs. 4.0 [+ or -] 0.3 min; P < 0.05). Furthermore, [[[K.sup.+]].sub.i] was higher from 0 to 1.5 min of the intense leg exercise period in AL compared with L (9.2 [+ or -] 0.7 vs. 6.4 [+ or -] 0.9 mM; P < 0.001) and at exhaustion (11.9 [+ or -] 0.5 vs. 10.3 [+ or -] 0.6 mM; P < 0.05). The dialysate content of carnosine was elevated by exercise, but low-intensity exercise resulted in higher dialysate carnosine concentrations than subsequent intense exercise. Furthermore, no relationship was found between carnosine concentrations and [[[K.sup.+]].sub.i]. Thus the present data suggest that microdialysis can be used to determine muscle [[[K.sup.+]].sub.i] kinetics during intense exercise, when low-intensity exercise is performed before the intense exercise. The high [[[K.sup.+]].sub.i] levels reached at exhaustion can be expected to cause fatigue, which is supported by the finding that a faster accumulation of interstitial [K.sup.+], induced by prior arm exercise, was associated with a reduced time to fatigue. muscle; fatigue; microdialysis; exercise; pH; potassium