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Determinants of repeated-sprint ability in well-trained team-sport athletes and endurance-trained athletes

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Abstract

To examine the importance of peak .VO(2) in determining repeated-sprint ability (RSA), we recruited 20 well-trained females (10 team-sport athletes and 10 endurance-trained runners; mean SD peak .VO(2): 3.3+/-0.2 L x min(-1)) who were homogenous with respect to peak .VO(2) (mean difference = 0.05 L x min(-1)). Tests consisted of a RSA cycle test (5 x 6-s max sprints every 30 s) and a peak .VO(2) test. Venous and capillary blood was sampled immediately before and after the 5 x 6-s cycle test for the determination of hypoxanthine concentration ([Hx]), lactate concentration ([La-]) and pH; blood buffer capacity (beta(blood)) was also estimated. The team-sport athletes had significantly higher peak power for the 1(st) sprint (P(1); W x kg(-1)), total work for 5 x 6-s sprints (W(tot); J x kg(-1)) and power decrement across the 5 sprints (P(dec)), (p<0.05). There were also significant between-group differences for post-test values of [Hx], [La-] and pH (p<0.05). While there was no significant difference in beta(blood) between the 2 groups (p=0.10), there was a moderate effect (d=0.77). These results suggest that factors in addition to peak .VO(2) are likely to be important for RSA.
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Determinants of repeated-sprint ability in well-trained team-sport athletes a...
D Bishop; M Spencer
Journal of Sports Medicine and Physical Fitness; Mar 2004; 44, 1; Health & Medical Complete
pg. 1
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
... The basis of plyometric training includes the stretch-shortening cycle (SSC), a concentric contraction preceded by a lengthening, i.e., eccentric muscle contraction [14,24]. Plyometric training appears to induce better neuromuscular coordination leading to increased power production [25,26]. Today's training programs for developing physical abilities strive for as much sport-specificity as possible. ...
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... All studies did report information related to participant background and fitness levels, thus unlikely negatively influencing findings (Guette et al. 2005;Häkkinen 1989). Nevertheless, training status (trained vs. untrained) does influence performance in different modalities (Bishop and Spencer 2004;Hopker et al. 2013;Riboli et al. 2021). Diurnal variation in performance is linked to training status, mode of exercise specificity and participant familiarisation and therefore needs to be well-controlled Giacomoni et al. 2006;Reilly et al. 1997). ...
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... Sprint Ability (RSA), i.e. the ability to repeat and endure significant sprinting, lasting few seconds each time [≈ 1 -10"] with intermittent recovery periods taking place many times during a match, is considered an important requisite in sports games, and particularly in soccer, both in males and females [1][2][3][4][5][6][7][8][9][10][11]. Results from several studies have highlighted the key role played by RSA, considered as one of the most important indicators in discriminating elite soccer players from sub-elite or amateur players [1,5,8,[12][13][14][15][16][17]. ...
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... Jump performance augmentation could be the result of neuromuscular adaptations such as greater neural drive of agonist muscles, changes in mechanical stiffness of tendons, size changes and/or the architecture of muscles, and changes in the mechanics of single fibers (Maffiuletti et al., 2002;de Villarreal et al., 2009;Thomas et al., 2009). Other potential mechanisms include (i) changes in muscle activation strategies (or intermuscular coordination) during vertical jumps, especially during the preparatory phase jump; and (ii) changes in the stretch reflex excitability (Bishop and Spencer, 2004;de Villarreal et al., 2009). Stølen et al. (2005) reported that 96% of sprint bouts during soccer match play are shorter than 30 m, with 49% being shorter than 10 m. ...
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Background: Postural balance represents a fundamental movement skill for the successful performance of everyday and sport-related activities. There is ample evidence on the effectiveness of balance training on balance performance in athletic and non-athletic population. However, less is known on potential transfer effects of other training types, such as plyometric jump training (PJT) on measures of balance. Given that PJT is a highly dynamic exercise mode with various forms of jump-landing tasks, high levels of postural control are needed to successfully perform PJT exercises. Accordingly, PJT has the potential to not only improve measures of muscle strength and power but also balance. Objective: To systematically review and synthetize evidence from randomized and non-randomized controlled trials regarding the effects of PJT on measures of balance in apparently healthy participants. Methods: Systematic literature searches were performed in the electronic databases PubMed, Web of Science, and SCOPUS. A PICOS approach was applied to define inclusion criteria, (i) apparently healthy participants, with no restrictions on their fitness level, sex, or age, (ii) a PJT program, (iii) active controls (any sport-related activity) or specific active controls (a specific exercise type such as balance training), (iv) assessment of dynamic, static balance pre- and post-PJT, (v) randomized controlled trials and controlled trials. The methodological quality of studies was assessed using the Physiotherapy Evidence Database (PEDro) scale. This meta-analysis was computed using the inverse variance random-effects model. The significance level was set at p < 0.05. Results: The initial search retrieved 8,251 plus 23 records identified through other sources. Forty-two articles met our inclusion criteria for qualitative and 38 for quantitative analysis (1,806 participants [990 males, 816 females], age range 9–63 years). PJT interventions lasted between 4 and 36 weeks. The median PEDro score was 6 and no study had low methodological quality (�3). The analysis revealed significant small effects of PJT on overall (dynamic and static) balance (ES = 0.46; 95% CI = 0.32–0.61; p < 0.001), dynamic (e.g., Y-balance test) balance (ES = 0.50; 95% CI = 0.30–0.71; p < 0.001), and static (e.g., flamingo balance test) balance (ES = 0.49; 95% CI = 0.31–0.67; p<0.001). The moderator analyses revealed that sex and/or age did not moderate balance performance outcomes. When PJT was compared to specific active controls (i.e., participants undergoing balance training, whole body vibration training, resistance training), both PJT and alternative training methods showed similar effects on overall (dynamic and static) balance (p = 0.534). Specifically, when PJT was compared to balance training, both training types showed similar effects on overall (dynamic and static) balance (p = 0.514). Conclusion: Compared to active controls, PJT showed small effects on overall balance, dynamic and static balance. Additionally, PJT produced similar balance improvements compared to other training types (i.e., balance training). Although PJT is widely used in athletic and recreational sport settings to improve athletes’ physical fitness (e.g., jumping; sprinting), our systematic review with meta-analysis is novel in as much as it indicates that PJT also improves balance performance. The observed PJT-related balance enhancements were irrespective of sex and participants’ age. Therefore, PJT appears to be an adequate training regime to improve balance in both, athletic and recreational settings.
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The relationship between running intensity and the accumulation of hypoxanthine and uric acid in plasma was studied in four well-trained runners. The runners each performed several 800-m runs at different velocities, each run being performed on separate days. Venous blood samples were collected before and at regular intervals after the runs. The concentration of hypoxanthine and uric acid was determined with high performance liquid chromatography (HPLC) in plasma extracts. A marked increase in the plasma concentration of both hypoxanthine and uric acid occurred simultaneously at intensities corresponding to 110, 108, 115 and 107% of VO2max for subject a, b, c and d, respectively. The sudden sharp increase in plasma concentration of hypoxanthine and uric acid may indicate that at a certain level of running intensity ATP catabolism exceeds the rate of ATP regeneration from the normal metabolic pathways.
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Muscle ATP, creatine phosphate and lactate, and blood pH and lactate were measured in 7 male sprinters before and after running 40, 60, 80 and 100 m at maximal speed. The sprinters were divided into two groups, group 1 being sprinters who achieved a higher maximal speed (10.07±0.13 m ·s−1) than group 2 (9.75±0.10 m ·s−1), and who also maintained the speed for a longer time. The breakdown of high-energy phosphate stores was significantly greater for group 1 than for group 2 for all distances other than 100 m; the breakdown of creatine phosphate for group 1 was almost the same for 40 m as for 100 m. Muscle and blood lactate began to accumulate during the 40 m exercise. The accumulation of blood lactate was linear (0.55±0.02 mmol · s−1 ·1−1) for all distances, and there were no differences between the groups. With 100 m sprints the end-levels of blood and muscle lactate were not high enough and the change in blood pH was not great enough for one to accept that lactate accumulation is responsible for the decrease in running speed over this distance. We concluded that 1) in short-term maximal exercise, performance depends on the capacity for using high-energy phosphates at the beginning of the exercise, and 2) the decrease in running speed begins when the high-energy phosphate stores are depleted and most of the energy must then be produced by glycolysis.
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Buffer capacity (beta) of skeletal muscle has been determined in trained (n = 7) and in sedentary subjects (n = 8). The trained subjects were active in ball games where a high degree of anaerobic energy utilization is required. Percentage fibre type occurrence in the thigh muscle was not significantly different in the two groups. However, there was a tendency towards a higher proportion of type I (slow-twitch) fibres (61.5 +/- 11.6% vs. 50.2 +/- 12.5%) and a lower proportion of type IIB fibres (2.1 +/- 3.5% vs 14.1 +/- 16.3%) in the trained subjects. The proportion of the cross-sectional area of the muscle biopsies that was made up of type I or type II fibres was not different in the two groups. All subjects performed an isometric contraction of the knee extensors to fatigue at 61% of their maximal voluntary contraction force. Muscle biopsies were taken from the quadriceps femoris muscle at rest and immediately after contraction. The buffer capacity of muscle was calculated from: beta = (Muscle lactate (work)-Muscle lactate (rest)/(Muscle pH (rest)-Muscle pH (work)). A higher buffer capacity (p less than 0.05) was observed in the trained subjects (beta = 194 +/- 30 mmol X pH-1 X kg-1 dry wt.) compared to the sedentary group (beta = 164 +/- 20) (mean +/- SD). An unexpected finding was that muscle lactate after contraction to fatigue was lower (30%, p less than 0.01) and muscle pH was higher (6.80 +/- 0.06 vs. 6.61 +/- 0.12, p less than 0.01) in the trained subjects than in the sedentary controls.(ABSTRACT TRUNCATED AT 250 WORDS)