The preferred transition speed (PTS) at which humans change their gait from walking to running wa... more The preferred transition speed (PTS) at which humans change their gait from walking to running was found to be lower than their energetically optimal transition speed (EOTS). This phenomenon has not been examined in racewalkers. The purpose of this study was to evaluate the PTS and the EOTS in racewalkers compared with controls. Eleven racewalkers and 13 control subjects participated in this study. Subjects arrived at the laboratory on three occasions. Visit I: determination of PTS. Subjects walked at a slow speed that was increased by 0.2 km x h every 30 s until they felt it was easier to run. Then, subjects ran at a high speed and the treadmill speed was reduced by 0.2 km x h every 30 s until they felt it was easier to walk. Visits II and III: subjects walked and ran at PTS - 1 km x h, PTS - 0.5 km x h, PTS, PTS + 0.5 km x h, and PTS + 1 km x h. At each stage, physiological measurements were recorded. PTS was 7.33 +/- 0.33 km x h in controls and 8.20 +/- 0.54 km.h in racewalkers (P < 0.001), and EOTS was 8.00 +/- 0.48 km x h in controls and 8.46 +/- 0.55 km x h in racewalkers (P = 0.039). There was a trend for a smaller difference between PTS and EOTS in racewalkers. V O2 was higher during running at the PTS in both groups (F1, 22 = 5.972, P = 0.023), and there was a trend for a group interaction (F1, 22 = 3.442, P = 0.077). HR and V E were higher at the PTS in racewalkers compared with controls. Racewalkers have a higher PTS and EOTS compared with controls. There is a trend for the difference between the PTS and the EOTS to be smaller in racewalkers compared with controls.
The preferred transition speed (PTS) at which humans change their gait from walking to running wa... more The preferred transition speed (PTS) at which humans change their gait from walking to running was found to be lower than their energetically optimal transition speed (EOTS). This phenomenon has not been examined in racewalkers. The purpose of this study was to evaluate the PTS and the EOTS in racewalkers compared with controls. Eleven racewalkers and 13 control subjects participated in this study. Subjects arrived at the laboratory on three occasions. Visit I: determination of PTS. Subjects walked at a slow speed that was increased by 0.2 km x h every 30 s until they felt it was easier to run. Then, subjects ran at a high speed and the treadmill speed was reduced by 0.2 km x h every 30 s until they felt it was easier to walk. Visits II and III: subjects walked and ran at PTS - 1 km x h, PTS - 0.5 km x h, PTS, PTS + 0.5 km x h, and PTS + 1 km x h. At each stage, physiological measurements were recorded. PTS was 7.33 +/- 0.33 km x h in controls and 8.20 +/- 0.54 km.h in racewalkers (P < 0.001), and EOTS was 8.00 +/- 0.48 km x h in controls and 8.46 +/- 0.55 km x h in racewalkers (P = 0.039). There was a trend for a smaller difference between PTS and EOTS in racewalkers. V O2 was higher during running at the PTS in both groups (F1, 22 = 5.972, P = 0.023), and there was a trend for a group interaction (F1, 22 = 3.442, P = 0.077). HR and V E were higher at the PTS in racewalkers compared with controls. Racewalkers have a higher PTS and EOTS compared with controls. There is a trend for the difference between the PTS and the EOTS to be smaller in racewalkers compared with controls.
Scandinavian Journal of Medicine & Science in Sports, 2010
The main purpose of this article was to review a series of studies (n=32; 24 observational and ei... more The main purpose of this article was to review a series of studies (n=32; 24 observational and eight experimental) examining vertical jump (VJ) performances in female and male volleyball players. The main findings of this review are (a) players of better performing teams have higher VJ values; (b) strength and conditioning programs that emphasize plyometric training can increase VJ performance; and (c) it is important to continue conditioning sessions throughout the season in order to maintain VJ performance. Three research limitations associated with the testing protocols and the strength and conditioning programs used in the studies were outlined: (a) the use of multiple testing protocols; (b) lack of experimental studies; and (c) lack of data on the effect of VJ performance on achieving success in actual games. Four recommendations for volleyball and strength and conditioning coaches were given: (a) Plyometric training should be included in the annual training program; (b) Interruptions in the conditioning program during the season should be avoided; (c) Overtraining during the pre-season should be avoided; and (d) VJ performance should be tested throughout the entire season.
This article reviews a series of studies (n = 51) examining physical attributes, physiological ch... more This article reviews a series of studies (n = 51) examining physical attributes, physiological characteristics, on-court performances and nutritional strategies of female and male elite basketball players. These studies included relevant information on physical and physiological variables, such as height, weight, somatotype, relative size, aerobic profile, strength, anaerobic power, agility and speed. Six main findings emerged from our review: (i) differences in physical attributes exist among playing positions and skill levels (e.g. guards tend to be lighter, shorter and more mesomorphic than centres); (ii) maximum aerobic capacity (VO(2max)) values of female and male players are 44.0-54.0 and 50-60 mLO(2)/kg/min, respectively; (iii) male and female players of higher skill levels tend to have higher vertical jump values; (iv) the more skilled female and male players are faster and more agile than the less skilled players; (v) guards tend to perform more high-intensity movements during game play compared with forwards and centres; and (vi) a water deficit of 2% of bodyweight can lead to reduced physical and mental performance during an actual game. Five limitations associated with the testing protocols used in the studies are outlined, among them the lack of a longitudinal approach, lack of tests performed under physical exertion conditions, and lack of studies using a time-motion analysis. In addition, three practical recommendations for the basketball coach and the strength and conditioning coach are presented. It is concluded that the data emerging from these studies, combined with the knowledge already obtained from the studies on physical and physiological characteristics of elite basketball players, should be applied by basketball and strength and conditioning coaches when planning training programmes for elite basketball players.
ABSTRACT This study examined the effectiveness of external and internal focusing attention instru... more ABSTRACT This study examined the effectiveness of external and internal focusing attention instructions on the performance of three throwing tasks under both quiet and distracted conditions. The main finding was that during acquisition, the external focus of attention led to improved performance when compared to internal focus of attention and control, but only under quiet conditions. It was also found that during auditory and visual distraction conditions, both types of focus attention produced similar levels of performance, and both groups were superior to the control condition. It is suggested that sport psychology consultants provide their athletes with external focusing attention instructions.
"The purpose of this study was to review a series of studies (n = 20) examining the effects ... more "The purpose of this study was to review a series of studies (n = 20) examining the effects of adding music to exercise programs in clinical populations and in the elderly. We found that the addition of music can (a) improve exercise capacity and increase patients’ motivation to participate in cardiac and pulmonary exercise rehabilitation programs; (b) lead to improved balance, greater ability to perform activities of daily living, and improved life satisfaction in elderly individuals; (c) enhance adherence and function of individuals suffering from neurological diseases such as Alzheimer’s and Parkinson’s; and (d) sustain these benefits if continued on a long-term basis. Based on the reviewed studies, a number of methodological concerns were presented, among them the choice of music style. One of the practical implications suggested for clinicians and practitioners was that the type of music should be individualized based on each patient’s musical preferences."
The main objective of this article was to review a series of studies (n = 31) on physical attribu... more The main objective of this article was to review a series of studies (n = 31) on physical attributes, physiological attributes, and on-court performances of female volleyball players. Empirical and practical knowledge emerging from studies on training-related issues in volleyball, such as body mass, fat-free mass, aerobic profile, strength, and agility and speed, should be integrated and applied when planning annual training programs for volleyball players. Based on our review, it was found that (a) players of a higher skill level are taller, somewhat heavier, and have higher vertical jump values than players of a lower level; (b) the aerobic profile of female volleyball players is similar to that of female basketball players; (c) ballistic resistance training can increase vertical jump values in female volleyball players; and (d) preseason conditioning should be conducted to prevent fatigue and reduced performance at the beginning of the season. Among the research concerns discussed in the article are that there is a lack data for on-court performance and time-motion analysis in female volleyball players and that more experimental/manipulative studies are needed to examine the effectiveness of different training programs on physiological attributes of female volleyball players. Two practical implications are suggested for volleyball and strength and conditioning coaches: (a) functional and nonfunctional overreaching should be carefully monitored when planning strength and conditioning programs, and (b) volleyball programs should include ballistic-type training.
The preferred transition speed (PTS) at which humans change their gait from walking to running wa... more The preferred transition speed (PTS) at which humans change their gait from walking to running was found to be lower than their energetically optimal transition speed (EOTS). This phenomenon has not been examined in racewalkers. The purpose of this study was to evaluate the PTS and the EOTS in racewalkers compared with controls. Eleven racewalkers and 13 control subjects participated in this study. Subjects arrived at the laboratory on three occasions. Visit I: determination of PTS. Subjects walked at a slow speed that was increased by 0.2 km x h every 30 s until they felt it was easier to run. Then, subjects ran at a high speed and the treadmill speed was reduced by 0.2 km x h every 30 s until they felt it was easier to walk. Visits II and III: subjects walked and ran at PTS - 1 km x h, PTS - 0.5 km x h, PTS, PTS + 0.5 km x h, and PTS + 1 km x h. At each stage, physiological measurements were recorded. PTS was 7.33 +/- 0.33 km x h in controls and 8.20 +/- 0.54 km.h in racewalkers (P < 0.001), and EOTS was 8.00 +/- 0.48 km x h in controls and 8.46 +/- 0.55 km x h in racewalkers (P = 0.039). There was a trend for a smaller difference between PTS and EOTS in racewalkers. V O2 was higher during running at the PTS in both groups (F1, 22 = 5.972, P = 0.023), and there was a trend for a group interaction (F1, 22 = 3.442, P = 0.077). HR and V E were higher at the PTS in racewalkers compared with controls. Racewalkers have a higher PTS and EOTS compared with controls. There is a trend for the difference between the PTS and the EOTS to be smaller in racewalkers compared with controls.
The preferred transition speed (PTS) at which humans change their gait from walking to running wa... more The preferred transition speed (PTS) at which humans change their gait from walking to running was found to be lower than their energetically optimal transition speed (EOTS). This phenomenon has not been examined in racewalkers. The purpose of this study was to evaluate the PTS and the EOTS in racewalkers compared with controls. Eleven racewalkers and 13 control subjects participated in this study. Subjects arrived at the laboratory on three occasions. Visit I: determination of PTS. Subjects walked at a slow speed that was increased by 0.2 km x h every 30 s until they felt it was easier to run. Then, subjects ran at a high speed and the treadmill speed was reduced by 0.2 km x h every 30 s until they felt it was easier to walk. Visits II and III: subjects walked and ran at PTS - 1 km x h, PTS - 0.5 km x h, PTS, PTS + 0.5 km x h, and PTS + 1 km x h. At each stage, physiological measurements were recorded. PTS was 7.33 +/- 0.33 km x h in controls and 8.20 +/- 0.54 km.h in racewalkers (P < 0.001), and EOTS was 8.00 +/- 0.48 km x h in controls and 8.46 +/- 0.55 km x h in racewalkers (P = 0.039). There was a trend for a smaller difference between PTS and EOTS in racewalkers. V O2 was higher during running at the PTS in both groups (F1, 22 = 5.972, P = 0.023), and there was a trend for a group interaction (F1, 22 = 3.442, P = 0.077). HR and V E were higher at the PTS in racewalkers compared with controls. Racewalkers have a higher PTS and EOTS compared with controls. There is a trend for the difference between the PTS and the EOTS to be smaller in racewalkers compared with controls.
Scandinavian Journal of Medicine & Science in Sports, 2010
The main purpose of this article was to review a series of studies (n=32; 24 observational and ei... more The main purpose of this article was to review a series of studies (n=32; 24 observational and eight experimental) examining vertical jump (VJ) performances in female and male volleyball players. The main findings of this review are (a) players of better performing teams have higher VJ values; (b) strength and conditioning programs that emphasize plyometric training can increase VJ performance; and (c) it is important to continue conditioning sessions throughout the season in order to maintain VJ performance. Three research limitations associated with the testing protocols and the strength and conditioning programs used in the studies were outlined: (a) the use of multiple testing protocols; (b) lack of experimental studies; and (c) lack of data on the effect of VJ performance on achieving success in actual games. Four recommendations for volleyball and strength and conditioning coaches were given: (a) Plyometric training should be included in the annual training program; (b) Interruptions in the conditioning program during the season should be avoided; (c) Overtraining during the pre-season should be avoided; and (d) VJ performance should be tested throughout the entire season.
This article reviews a series of studies (n = 51) examining physical attributes, physiological ch... more This article reviews a series of studies (n = 51) examining physical attributes, physiological characteristics, on-court performances and nutritional strategies of female and male elite basketball players. These studies included relevant information on physical and physiological variables, such as height, weight, somatotype, relative size, aerobic profile, strength, anaerobic power, agility and speed. Six main findings emerged from our review: (i) differences in physical attributes exist among playing positions and skill levels (e.g. guards tend to be lighter, shorter and more mesomorphic than centres); (ii) maximum aerobic capacity (VO(2max)) values of female and male players are 44.0-54.0 and 50-60 mLO(2)/kg/min, respectively; (iii) male and female players of higher skill levels tend to have higher vertical jump values; (iv) the more skilled female and male players are faster and more agile than the less skilled players; (v) guards tend to perform more high-intensity movements during game play compared with forwards and centres; and (vi) a water deficit of 2% of bodyweight can lead to reduced physical and mental performance during an actual game. Five limitations associated with the testing protocols used in the studies are outlined, among them the lack of a longitudinal approach, lack of tests performed under physical exertion conditions, and lack of studies using a time-motion analysis. In addition, three practical recommendations for the basketball coach and the strength and conditioning coach are presented. It is concluded that the data emerging from these studies, combined with the knowledge already obtained from the studies on physical and physiological characteristics of elite basketball players, should be applied by basketball and strength and conditioning coaches when planning training programmes for elite basketball players.
ABSTRACT This study examined the effectiveness of external and internal focusing attention instru... more ABSTRACT This study examined the effectiveness of external and internal focusing attention instructions on the performance of three throwing tasks under both quiet and distracted conditions. The main finding was that during acquisition, the external focus of attention led to improved performance when compared to internal focus of attention and control, but only under quiet conditions. It was also found that during auditory and visual distraction conditions, both types of focus attention produced similar levels of performance, and both groups were superior to the control condition. It is suggested that sport psychology consultants provide their athletes with external focusing attention instructions.
"The purpose of this study was to review a series of studies (n = 20) examining the effects ... more "The purpose of this study was to review a series of studies (n = 20) examining the effects of adding music to exercise programs in clinical populations and in the elderly. We found that the addition of music can (a) improve exercise capacity and increase patients’ motivation to participate in cardiac and pulmonary exercise rehabilitation programs; (b) lead to improved balance, greater ability to perform activities of daily living, and improved life satisfaction in elderly individuals; (c) enhance adherence and function of individuals suffering from neurological diseases such as Alzheimer’s and Parkinson’s; and (d) sustain these benefits if continued on a long-term basis. Based on the reviewed studies, a number of methodological concerns were presented, among them the choice of music style. One of the practical implications suggested for clinicians and practitioners was that the type of music should be individualized based on each patient’s musical preferences."
The main objective of this article was to review a series of studies (n = 31) on physical attribu... more The main objective of this article was to review a series of studies (n = 31) on physical attributes, physiological attributes, and on-court performances of female volleyball players. Empirical and practical knowledge emerging from studies on training-related issues in volleyball, such as body mass, fat-free mass, aerobic profile, strength, and agility and speed, should be integrated and applied when planning annual training programs for volleyball players. Based on our review, it was found that (a) players of a higher skill level are taller, somewhat heavier, and have higher vertical jump values than players of a lower level; (b) the aerobic profile of female volleyball players is similar to that of female basketball players; (c) ballistic resistance training can increase vertical jump values in female volleyball players; and (d) preseason conditioning should be conducted to prevent fatigue and reduced performance at the beginning of the season. Among the research concerns discussed in the article are that there is a lack data for on-court performance and time-motion analysis in female volleyball players and that more experimental/manipulative studies are needed to examine the effectiveness of different training programs on physiological attributes of female volleyball players. Two practical implications are suggested for volleyball and strength and conditioning coaches: (a) functional and nonfunctional overreaching should be carefully monitored when planning strength and conditioning programs, and (b) volleyball programs should include ballistic-type training.
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