1. |
- Andersson, Helena M., et al.
(författare)
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Elite female soccer players perform more high-intensity running when playing in international games compared with domestic league games
- 2010
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Ingår i: Journal of Strength and Conditioning Research. - Philadelphia, USA : Lippincott Williams & Wilkins. - 1064-8011 .- 1533-4287. ; 24:4, s. 912-919
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Tidskriftsartikel (refereegranskat)abstract
- 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.
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2. |
- Bendiksen, M., et al.
(författare)
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Application of the Copenhagen Soccer Test in high-level women players - locomotor activities, physiological response and sprint performance
- 2013
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Ingår i: Human Movement Science. - : Elsevier BV. - 0167-9457. ; 32:6, s. 1430-1442
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Tidskriftsartikel (refereegranskat)abstract
- We evaluated the physiological response, sprint performance and technical ability in various phases of the Copenhagen Soccer Test for Women (CSTw.) and investigated whether the locomotor activities of the CSTw were comparable to competitive match-play (CM). Physiological measurements and physical/technical assessments were performed during CSTw for eleven Norwegian high-level women soccer players. The activity pattern during CSTw and CM was monitored using the ZXY tracking system. No differences were observed between CSTw and CM with regards to total distance covered (10093 +/- 94 and 9674 +/- 191 m), high intensity running (1278 +/- 67 and 1193 +/- 115 m) or sprinting (422 +/- 55 and 372 +/- 46 m) (p > .05). During CSTw, average HR was 85 +/- 2%HRmax with 35 +/- 2% playing time >90%HRmax. Blood lactate increased (p < .05) from 1.4 +/- 0.3 mM at rest to an average of 4.7 +/- 0.5 mM during CSTw, with no changes during the test. Blood glucose was 5.4 +/- 0.3 mM at rest and remained unaltered during CSTw. Sprint performance (2 x 20 in) decreased (p < .05) by 3% during CSTw (8.19 +/- 0.06-8.47 +/- 0.10 s). In conclusion, the locomotor activities during CSTw were comparable to that of high-level competitive match-play. The physiological demands of the CSTw were high, with no changes in heart rate, blood lactate or technical performance during the test, but a lowered sprint performance towards the end of the test. (C) 2013 Elsevier B.V. All rights reserved.
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3. |
- Bowtell, J. L., et al.
(författare)
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Improved Exercise Tolerance with Caffeine Is Associated with Modulation of both Peripheral and Central Neural Processes in Human Participants
- 2018
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Ingår i: Frontiers in Nutrition. - : Frontiers Media SA. - 2296-861X. ; 5
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Tidskriftsartikel (refereegranskat)abstract
- Background: Caffeine has been shown to enhance exercise performance and capacity. The mechanisms remain unclear but are suggested to relate to adenosine receptor antagonism, resulting in increased central motor drive, reduced perception of effort, and altered peripheral processes such as enhanced calcium handling and extracellular potassium regulation. Our aims were to investigate how caffeine (i) affects knee extensor PCr kinetics and pH during repeated sets of single-leg knee extensor exercise to task failure and (ii) modulates the interplay between central and peripheral neural processes. We hypothesized that the caffeine-induced extension of exercise capacity during repeated sets of exercise would occur despite greater disturbance of the muscle milieu due to enhanced peripheral and corticospinal excitatory output, central motor drive, and muscle contractility. Methods: Nine healthy active young men performed five sets of intense single-leg knee extensor exercise to task failure on four separate occasions: for two visits (6 mg.kg(-1) caffeine vs placebo), quadriceps P-31-magnetic resonance spectroscopy scans were performed to quantify phosphocreatine kinetics and pH, and for the remaining two visits (6 mg.kg-1 caffeine vs placebo), femoral nerve electrical and transcranial magnetic stimulation of the quadriceps cortical motor area were applied pre- and post exercise. Results: The total exercise time was 17.9 +/- 6.0% longer in the caffeine (1,225 +/- 86 s) than in the placebo trial (1,049 +/- 73 s, p = 0.016), and muscle phosphocreatine concentration and pH (p < 0.05) were significantly lower in the latter sets of exercise after caffeine ingestion. Voluntary activation (VA) (peripheral, p = 0.007; but not supraspinal, p = 0.074), motor-evoked potential (MEP) amplitude (p = 0.007), and contractility (contraction time, p = 0.009; and relaxation rate, p = 0.003) were significantly higher after caffeine consumption, but at task failure MEP amplitude and VA were not different from placebo. Caffeine prevented the reduction in M-wave amplitude that occurred at task failure (p = 0.039). Conclusion: Caffeine supplementation improved high-intensity exercise tolerance despite greater-end exercise knee extensor phosphocreatine depletion and H+ accumulation. Caffeine-induced increases in central motor drive and corticospinal excitability were attenuated at task failure. This may have been induced by the afferent feedback of the greater disturbance of the muscle milieu, resulting in a stronger inhibitory input to the spinal and supraspinal motor neurons. However, causality needs to be established through further experiments.
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4. |
- Bowtell, J. L., et al.
(författare)
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Short Duration Small Sided Football and to a Lesser Extent Whole Body Vibration Exercise Induce Acute Changes in Markers of Bone Turnover
- 2016
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Ingår i: Biomed Research International. - : Hindawi Limited. - 2314-6133 .- 2314-6141.
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Tidskriftsartikel (refereegranskat)abstract
- We aimed to study whether short-duration vibration exercise or football sessions of two different durations acutely changed plasma markers of bone turnover and muscle strain. Inactive premenopausal women (n = 56) were randomized to complete a single bout of short (FG15) or long duration (FG60) small sided football or low magnitude whole body vibration training (VIB). Procollagen type 1 amino-terminal propeptide (P1NP) was increased during exercise for FG15 (51.6 +/- 23.0 to 56.5 +/- 22.5 mu g.L-1, mean +/- SD, P < 0.05) and FG60 (42.6 +/- 11.8 to 50.2 +/- 12.8 mu g.L-1, P < 0.05) but not for VIB (38.8 +/- 15.1 to 36.6 +/- 14.7 mu g.L-1, P > 0.05). An increase in osteocalcin was observed 48 h after exercise (P < 0.05), which did not differ between exercise groups. C-terminal telopeptide of type 1 collagen was not affected by exercise. Blood lactate concentration increased during exercise for FG15 (0.6 +/- 0.2 to 3.4 +/- 1.2mM) and FG60 (0.6 +/- 0.2 to 3.3 +/- 2.0 mM), but not for VIB (0.6 +/- 0.2 to 0.8 +/- 0.4mM) (P < 0.05). Plasma creatine kinase increased by 55 +/- 63% and 137 +/- 119% 48 h after FG15 and FG60 (P < 0.05), but not after VIB (26 +/- 54%, NS). In contrast to the minor elevation in osteocalcin in response to a single session of vibration exercise, both short and longer durations of small sided football acutely increased plasma P1NP, osteocalcin, and creatine kinase. This may contribute to favorable effects of chronic training on musculoskeletal health.
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6. |
- Bradley, P. S., et al.
(författare)
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Gender differences in match performance characteristics of soccer players competing in the UEFA Champions League
- 2014
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Ingår i: Human Movement Science. - : Elsevier BV. - 0167-9457. ; 33, s. 159-171
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to examine gender differences in match performance characteristics of elite soccer players. Fifty-four male and fifty-nine female soccer players were tracked during UEFA Champions League matches using a multi-camera system (Amisco, Nice, France). Male players covered more (P<.01) distance than female players in total during a match (Effect Size [ES]: 0.5) and at higher speed thresholds (>15, >18, 18-21, 21-23, 23-25 and >27 km h(-1); ES: 0.7-1.4). Decrements in the second versus first half (P<.01) were only evident in female players for the distance covered in total and at selected speed thresholds (12-15, >12 and >15 km h(-1); ES: 0.6). Male central midfielders covered more (P<.01) total distance during a match than female central midfielders and at selected speed thresholds (15-23 km h(-1); ES: 1.3-2.2). Male full-backs and wide midfielders covered a greater distance (P<.01) than female players in the same positions at higher speed thresholds (>15, 21-23, 23-25, 25-27 and >27 km h(-1); ES: 1.5-3.1). The distance covered during the most intense 5 min period of the match (>15 km h(-1)) was higher (P<.01) in male compared to female players (ES: 1.0) but no distance deficit in the next versus the average 5 min period was observed for either gender (ES: 0.1-0.2). No gender differences were found for technical events such as the number of ball touches, time in possession of the ball or total duels won during both halves and the entire match (ES: 0.1-0.3). However, female players lost the ball more often (P<.05) and displayed lower pass completion rates than male players during both halves and the entire match (ES: 0.5-0.9). The data demonstrate that large gender differences exist for match performance characteristics of players competing at the highest competitive standard of European soccer. Such detailed analyses could be useful for gender-specific training information for optimal preparation. However, more research is warranted to establish gender-specific speed thresholds for elite soccer players. Crown Copyright (C) 2013 Published by Elsevier B.V. All rights reserved.
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7. |
- Connolly, L. J., et al.
(författare)
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Effects of small-volume soccer and vibration training on body composition, aerobic fitness, and muscular PCr kinetics for inactive women aged 20-45
- 2014
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Ingår i: Journal of Sport and Health Science. - : Elsevier BV. - 2095-2546. ; 3:4, s. 284-292
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: The present study investigated the effects of 16 weeks of small-volume, small-sided soccer training soccer group (SG, n = 13) and oscillating whole-body vibration training vibration group (VG, n = 17) on body composition, aerobic fitness, and muscle PCr kinetics in healthy inactive premenopausal women in comparison with an inactive control group (CO, n = 14). Methods: Training for SG and VG consisted of twice-weekly 15-min sessions with average heart rates (HRs) of similar to 155 and 90 bpm respectively. Pre- and post-measurements of body composition (DXA), phosphocreatine (PCr) on-and off-kinetics, and HR measurements during standardised submaximal exercise were performed. Results: After 16 weeks of training in SG, fat percentage was lowered (p = 0.03) by 1.7% +/- 2.4% from 37.5% +/- 6.9% to 35.8% +/- 6.2% and the PCr decrease in the quadriceps during knee-extension ramp exercise was attenuated (4% +/- 8%, p = 0.04), with no changes in VG or CO (time-group effect: p = 0.03 and p = 0.03). Submaximal exercise HR was also reduced in SG after 16 weeks of training (6% +/- 5% of HRmax, p = 0.01). Conclusion: Short duration soccer training for 16 weeks appears to be sufficient to induce favourable changes in body composition and indicators of aerobic fitness and muscle oxidative capacity in untrained premenopausal women. Copyright (C) 2014, Shanghai University of Sport. Production and hosting by Elsevier B.V. All rights reserved.
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8. |
- Connolly, L. J., et al.
(författare)
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Low-volume high-intensity swim training is superior to high-volume low-intensity training in relation to insulin sensitivity and glucose control in inactive middle-aged women
- 2016
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Ingår i: European Journal of Applied Physiology. - : Springer Science and Business Media LLC. - 1439-6319 .- 1439-6327. ; 116:10, s. 1889-1897
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Tidskriftsartikel (refereegranskat)abstract
- We tested the hypothesis that low-volume high-intensity swimming has a larger impact on insulin sensitivity and glucose control than high-volume low-intensity swimming in inactive premenopausal women with mild hypertension. Sixty-two untrained premenopausal women were randomised to an inactive control (n = 20; CON), a high-intensity low-volume (n = 21; HIT) or a low-intensity high-volume (n = 21; LIT) training group. During the 15-week intervention period, HIT performed 3 weekly 6-10 x 30-s all-out swimming intervals (average heart rate (HR) = 86 +/- 3 % HRmax) interspersed by 2-min recovery periods and LIT swam continuously for 1 h at low intensity (average HR = 73 +/- 3 % HRmax). Fasting blood samples were taken and an oral glucose tolerance test (OGTT) was conducted pre- and post-intervention. After HIT, resting plasma [insulin] was lowered (17 +/- 34 %; P < 0.05) but remained similar after LIT and CON. Following HIT, 60-min OGTT plasma [insulin] and [glucose] was lowered (24 +/- 30 % and 10 +/- 16 %; P < 0.05) but remained similar after LIT and CON. Total area under the curve for plasma [glucose] was lower (P < 0.05) after HIT than LIT (660 +/- 141 vs. 860 +/- 325 mmol min L-1). Insulin sensitivity (HOMA-IR) had increased (P < 0.05) by 22 +/- 34 % after HIT, with no significant change after LIT or CON, respectively. Plasma soluble intracellular cell adhesion molecule 1 was lowered (P < 0.05) by 4 +/- 8 and 3 +/- 9 % after HIT and CON, respectively, while plasma soluble vascular cell adhesion molecule 1 had decreased (P < 0.05) by 8 +/- 23 % after HIT only. These findings suggest that low-volume high-intensity intermittent swimming is an effective and time-efficient training strategy for improving insulin sensitivity, glucose control and biomarkers of vascular function in inactive, middle-aged mildly hypertensive women.
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9. |
- Draganidis, D., et al.
(författare)
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Recovery Kinetics of Knee Flexor and Extensor Strength after a Football Match
- 2015
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Ingår i: Plos One. - : Public Library of Science (PLoS). - 1932-6203. ; 10:6
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Tidskriftsartikel (refereegranskat)abstract
- We examined the temporal changes of isokinetic strength performance of knee flexor (KF) and extensor (KE) strength after a footballmatch. Players were randomly assigned to a control (N = 14, participated only in measurements and practices) or an experimental group (N = 20, participated also in a football match). Participants trained daily during the two days after the match. Match and training overload was monitored with GPS devices. Venous blood was sampled and muscle damage was assessed pre-match, post-match and at 12h, 36h and 60h post-match. Isometric strength as well as eccentric and concentric peak torque of knee flexors and extensors in both limbs (dominant and non-dominant) were measured on an isokinetic dynamometer at baseline and at 12h, 36h and 60h after the match. Functional (KFecc/KEcon) and conventional (KFcon/KEcon) ratios were then calculated. Only eccentric peak torque of knee flexors declined at 60h after the match in the control group. In the experimental group: a) isometric strength of knee extensors and knee flexors declined (P<0.05) at 12h (both limbs) and 36h (dominant limb only), b) eccentric and concentric peak torque of knee extensors and flexors declined (P<0.05) in both limbs for 36h at 60 degrees/s and for 60h at 180 degrees/s with eccentric peak torque of knee flexors demonstrating a greater (P<0.05) reduction than concentric peak torque, c) strength deterioration was greater (P<0.05) at 180 degrees/s and in dominant limb, d) the functional ratio was more sensitive tomatch-induced fatigue demonstrating a more prolonged decline. Discriminant and regression analysis revealed that strength deterioration and recovery may be related to the amount of eccentric actions performed during the match and athletes' football-specific conditioning. Our data suggest that recovery kinetics of knee flexor and extensor strength after a football match demonstrate strength, limb and velocity specificity and may depend on match physical overload and players' physical conditioning level.
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10. |
- Ermidis, G., et al.
(författare)
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Technical demands across playing positions of the Asian Cup in male football
- 2019
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Ingår i: International Journal of Performance Analysis in Sport. - : Informa UK Limited. - 1474-8185 .- 2474-8668. ; 19:4, s. 530-542
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to compare technical variables by playing positions in football during the 2015 Asian Cup. Top-level male football players (n = 202) that completed the full 90-min game were considered. Match-analysis data were collected using OPTA Sportsdata (www.optasports.com). Kruskal–Wallis H non-parametric test revealed that external midfielders (EM) scored more goals than fullbacks (FB) (p = 0.042), and that FB had less attempts (to score a goal) than central midfielders (CM), EM and forwards (FW), whereas central defenders (CD) had less attempts than FW (p < 0.05). CM performed more passes than CD, EM and FW, while FW performed less passes than CD, FB and CM. CD and CM performed more successful passes than FB and FW (p < 0.05), and CM also had more passes than EM (p < 0.05). Moreover, FW had more aerial duels (50–50 contests) than CM, FB and EM (p < 0.05). Similar numbers of aerial duels occurred for CD and FW. Ground duels occurred less (p < 0.05) frequently for CD compared to FB, CM, EM and FW. In conclusion, differences in technical events were observed between the various playing positions during competitive elite football matches, making it valuable considering the technical demands of players during group training as well as individualised training. © 2019, © 2019 Cardiff Metropolitan University.
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