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The effects of a combined resisted jump training and rugby-conditioning program on selected physical, motor ability and anthropometric components of rugby players / Jacobus Johannes OosthuizenOosthuizen, Jacobus Johannes January 2013 (has links)
Plyometrics is primarily used by coaches and sport scientists to improve explosive power among
athletes who participate in dynamic, high intensity type of sports. One of the plyometric-related
training methods that has received attention in recent years, is loaded or resistance (resistive) jump
training. Limited research does, however, exist with regard to the benefits and use of this training
method as well as in conjunction with other training methods, especially among team sport
participants. It is against this background that the research objectives of this study were firstly, to
examine the effects of a 4-week combined rugby-conditioning and resisted jump training program
compared to a combined rugby-conditioning and normal jump training program, on selected
physical, motor ability and anthropometric components of university-level rugby players. The
second objective was to examine the acute effects of a resisted compared to a normal jump training
session on selected physical and motor ability components of university-level rugby players.
Thirty rugby players (age: 19.60 ± 0.79 years) from the first and second u/19 and u/21 rugby teams
of a university in South Africa were randomly selected to participate in the first part of study. For
the second part of the study thirty senior rugby players (1st and 2nd senior teams) (age: 21.78 ± 1.86
years) of the Rugby Institute at a university in South Africa were randomly selected to participate
in the study. For both studies the thirty players were in turn randomly divided into two groups of
fifteen players each. One group formed the experimental and the other group the control group.
The first objective was tested by subjecting the players to a 4-week combined sport-specific and
resisted plyometric training program (experimental group) or a combined sport-specific and
normal plyometric training program to investigate the adaptations of body composition, lower
body flexibility, explosive leg power, speed, agility and leg strength. After a 10-week period
(“wash-out period”) during which subjects continued with their normal rugby-conditioning
program, the same testing procedures as before, were executed by following a crossover design. In
order to test the second objective of the study players’ body weight and height were firstly
measured after which they were subjected to a thorough warm-up, followed by the execution of
the flexibility;Vertical Jump Test (VJT); 5-, 10- and 20 m speed tests; the Illinois Agility Run Test
(IART) and the 6RM (repetition maximum) Smith Machine Squat Test (6RM-SMST). The
experimental group was subject to the resisted jump training session on the Vertimax whereas the
control group executed the same exercises on the floor. Directly after the training session each of the players again completed the test battery. After the first week, a crossover design was
implemented.
Although the overall study (independent t-test and main effect ANOVA) results of the first study
suggested that the experimental group experienced more positive changes, especially with regard
to the body fat, skeletal mass and somatotype-related anthropometric and flexibility-related
measurements, only relaxed upper-arm girth, ectomorphy, left Active-straight-leg-raise-test and
the left Modified Thomas Quadriceps Test values showed significant differences (p < 0.05) when
the two groups of players were compared. Although the experimental group demonstrated
significantly better average scores in the majority of the last-mentioned components, this group
experienced a significantly higher reduction in relaxed upper-arm girth due to the conditioning
program than the control group. The main effect ANOVA results of the acute study showed that no
significant differences were obtained for any of the measured components between an acute
resisted and normal jump training session.
To conclude, the study revealed that a 4-week combined rugby-conditioning and resisted jump
training program (experimental group) did not benefit university-level rugby players significantly
more with regard to selected physical, motor ability and anthropometric components than a
combined rugby-conditioning and normal jump training program (control group). Furthermore,
despite the fact that the acute resisted and normal jump training exercises met all the requirements
to produce post-activation potentiation, the study results showed that these exercise sessions did
not lead to any significant acute changes in the physical and motor ability components of
university-level rugby players. / MA (Sport Science), North-West University, Potchefstroom Campus, 2014
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The effects of a combined resisted jump training and rugby-conditioning program on selected physical, motor ability and anthropometric components of rugby players / Jacobus Johannes OosthuizenOosthuizen, Jacobus Johannes January 2013 (has links)
Plyometrics is primarily used by coaches and sport scientists to improve explosive power among
athletes who participate in dynamic, high intensity type of sports. One of the plyometric-related
training methods that has received attention in recent years, is loaded or resistance (resistive) jump
training. Limited research does, however, exist with regard to the benefits and use of this training
method as well as in conjunction with other training methods, especially among team sport
participants. It is against this background that the research objectives of this study were firstly, to
examine the effects of a 4-week combined rugby-conditioning and resisted jump training program
compared to a combined rugby-conditioning and normal jump training program, on selected
physical, motor ability and anthropometric components of university-level rugby players. The
second objective was to examine the acute effects of a resisted compared to a normal jump training
session on selected physical and motor ability components of university-level rugby players.
Thirty rugby players (age: 19.60 ± 0.79 years) from the first and second u/19 and u/21 rugby teams
of a university in South Africa were randomly selected to participate in the first part of study. For
the second part of the study thirty senior rugby players (1st and 2nd senior teams) (age: 21.78 ± 1.86
years) of the Rugby Institute at a university in South Africa were randomly selected to participate
in the study. For both studies the thirty players were in turn randomly divided into two groups of
fifteen players each. One group formed the experimental and the other group the control group.
The first objective was tested by subjecting the players to a 4-week combined sport-specific and
resisted plyometric training program (experimental group) or a combined sport-specific and
normal plyometric training program to investigate the adaptations of body composition, lower
body flexibility, explosive leg power, speed, agility and leg strength. After a 10-week period
(“wash-out period”) during which subjects continued with their normal rugby-conditioning
program, the same testing procedures as before, were executed by following a crossover design. In
order to test the second objective of the study players’ body weight and height were firstly
measured after which they were subjected to a thorough warm-up, followed by the execution of
the flexibility;Vertical Jump Test (VJT); 5-, 10- and 20 m speed tests; the Illinois Agility Run Test
(IART) and the 6RM (repetition maximum) Smith Machine Squat Test (6RM-SMST). The
experimental group was subject to the resisted jump training session on the Vertimax whereas the
control group executed the same exercises on the floor. Directly after the training session each of the players again completed the test battery. After the first week, a crossover design was
implemented.
Although the overall study (independent t-test and main effect ANOVA) results of the first study
suggested that the experimental group experienced more positive changes, especially with regard
to the body fat, skeletal mass and somatotype-related anthropometric and flexibility-related
measurements, only relaxed upper-arm girth, ectomorphy, left Active-straight-leg-raise-test and
the left Modified Thomas Quadriceps Test values showed significant differences (p < 0.05) when
the two groups of players were compared. Although the experimental group demonstrated
significantly better average scores in the majority of the last-mentioned components, this group
experienced a significantly higher reduction in relaxed upper-arm girth due to the conditioning
program than the control group. The main effect ANOVA results of the acute study showed that no
significant differences were obtained for any of the measured components between an acute
resisted and normal jump training session.
To conclude, the study revealed that a 4-week combined rugby-conditioning and resisted jump
training program (experimental group) did not benefit university-level rugby players significantly
more with regard to selected physical, motor ability and anthropometric components than a
combined rugby-conditioning and normal jump training program (control group). Furthermore,
despite the fact that the acute resisted and normal jump training exercises met all the requirements
to produce post-activation potentiation, the study results showed that these exercise sessions did
not lead to any significant acute changes in the physical and motor ability components of
university-level rugby players. / MA (Sport Science), North-West University, Potchefstroom Campus, 2014
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Selected anthropometric, physical and motor performance predictors of lower body explosive power in adolescents : the PAHL study / Koert Nicolaas van der WaltVan der Walt, Koert Nicolaas January 2014 (has links)
Lower body explosive power (LBEP) forms a critical component in any individual and team sport performance and it is therefore essential to develop a means of predicting LBEP in adolescents for early identification of future talent in various sporting codes. LBEP is frequently used by athletes during matches or competitions where explosive movements such as jumping, agility running and sprinting are required for successful performance. These movements are usually found in individual sports such as long jump and high jump as well as in team sports such as basketball, volleyball and soccer. To date not much literature is available on LBEP, especially with regard to LBEP prediction models. Furthermore, studies on adolescents are scarce and a LBEP prediction model has not yet been developed for a South African adolescent population. It is against this background that the objectives of this study were firstly, to develop a LBEP prediction model from various physical and motor performance components among a cohort of adolescents living in the Tlokwe local municipality of Dr Kenneth Kaunda district in the North-West Province, South Africa; and secondly, to develop a LBEP prediction model from several anthropometric measurements among a cohort of male and female adolescents living in the Tlokwe local municipality of Dr Kenneth Kaunda district in the North-West Province, South Africa. Two hundred and fourteen (15.8±0.68 years) 15-year-old adolescents (126 females, 88 males) from 6 surrounding schools within the Tlokwe local municipality of Dr Kenneth Kaunda district in the North-West Province of South Africa were purposefully selected from pre-acquired class lists took part in the study. Data was collected by means of various questionnaires as well as anthropometrical, physical and motor performance tests. For representation of LBEP a principal component factor analysis was done and the results indicated that the vertical jump test (VJT) was the best indicator of LBEP in the cohort of adolescents.
With regard to the anthropometrical related LBEP prediction model, the forward stepwise regression analysis yielded a correlation coefficient of R2 = 0.69. The following variables contributed significantly (p≤0.001) to the anthropometrical LBEP prediction model: stature (57%), muscle mass percentage (10%) and maturity age (3%). The LBEP prediction model that was developed equated to LBEP (vertical jump) = -136.30 + 0.84(stature) + 0.7(muscle mass percentage) + 4.6(maturity age). Variables other than the variables that formed part of the study could explain the further 31% variance in the LBEP of the adolescents. The physical and motor performance LBEP prediction model indicated that gender (39%) and 10 m speed (7%) contributed significantly (p ≤ 0.001) to the overall prediction of the LBEP of the adolescents. The LBEP prediction model delivered a stepwise forward regression analysis coefficient of R2=0.458 and a prediction formula LBEP = 68.21 + 9.82 (gender) – 18.33(10 m speed). The remaining 56% of the variance in the results could be explained by other factors than the variables considered in the study. In conclusion, to the best of the researchers’ knowledge, this is the first study which has made an attempt at developing LBEP prediction models from the anthropometrical, physical and motor performance components of a cohort of adolescents of South Africa. The prediction models developed in the study will assist teachers sport scientists and sporting coaches who have limited resources available, to measure and calculate LBEP in adolescents, with the means to do so in South Africa. Further high quality studies are necessary to further improve and develop such prediction models for various age groups of adolescents in the greater South Africa. / MSc (Sport Science), North-West University, Potchefstroom Campus, 2014
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Selected anthropometric, physical and motor performance predictors of lower body explosive power in adolescents : the PAHL study / Koert Nicolaas van der WaltVan der Walt, Koert Nicolaas January 2014 (has links)
Lower body explosive power (LBEP) forms a critical component in any individual and team sport performance and it is therefore essential to develop a means of predicting LBEP in adolescents for early identification of future talent in various sporting codes. LBEP is frequently used by athletes during matches or competitions where explosive movements such as jumping, agility running and sprinting are required for successful performance. These movements are usually found in individual sports such as long jump and high jump as well as in team sports such as basketball, volleyball and soccer. To date not much literature is available on LBEP, especially with regard to LBEP prediction models. Furthermore, studies on adolescents are scarce and a LBEP prediction model has not yet been developed for a South African adolescent population. It is against this background that the objectives of this study were firstly, to develop a LBEP prediction model from various physical and motor performance components among a cohort of adolescents living in the Tlokwe local municipality of Dr Kenneth Kaunda district in the North-West Province, South Africa; and secondly, to develop a LBEP prediction model from several anthropometric measurements among a cohort of male and female adolescents living in the Tlokwe local municipality of Dr Kenneth Kaunda district in the North-West Province, South Africa. Two hundred and fourteen (15.8±0.68 years) 15-year-old adolescents (126 females, 88 males) from 6 surrounding schools within the Tlokwe local municipality of Dr Kenneth Kaunda district in the North-West Province of South Africa were purposefully selected from pre-acquired class lists took part in the study. Data was collected by means of various questionnaires as well as anthropometrical, physical and motor performance tests. For representation of LBEP a principal component factor analysis was done and the results indicated that the vertical jump test (VJT) was the best indicator of LBEP in the cohort of adolescents.
With regard to the anthropometrical related LBEP prediction model, the forward stepwise regression analysis yielded a correlation coefficient of R2 = 0.69. The following variables contributed significantly (p≤0.001) to the anthropometrical LBEP prediction model: stature (57%), muscle mass percentage (10%) and maturity age (3%). The LBEP prediction model that was developed equated to LBEP (vertical jump) = -136.30 + 0.84(stature) + 0.7(muscle mass percentage) + 4.6(maturity age). Variables other than the variables that formed part of the study could explain the further 31% variance in the LBEP of the adolescents. The physical and motor performance LBEP prediction model indicated that gender (39%) and 10 m speed (7%) contributed significantly (p ≤ 0.001) to the overall prediction of the LBEP of the adolescents. The LBEP prediction model delivered a stepwise forward regression analysis coefficient of R2=0.458 and a prediction formula LBEP = 68.21 + 9.82 (gender) – 18.33(10 m speed). The remaining 56% of the variance in the results could be explained by other factors than the variables considered in the study. In conclusion, to the best of the researchers’ knowledge, this is the first study which has made an attempt at developing LBEP prediction models from the anthropometrical, physical and motor performance components of a cohort of adolescents of South Africa. The prediction models developed in the study will assist teachers sport scientists and sporting coaches who have limited resources available, to measure and calculate LBEP in adolescents, with the means to do so in South Africa. Further high quality studies are necessary to further improve and develop such prediction models for various age groups of adolescents in the greater South Africa. / MSc (Sport Science), North-West University, Potchefstroom Campus, 2014
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Sportspesifieke inoefening en antropometriese, fisieke en motoriese vereistes van 15– tot 17–jaar oue vroulike netbalspelers / Y. WillemseWillemse, Yolandi January 2010 (has links)
In the light of the facts given in literature it is evident that players in the game of netball
need to meet specific anthropometric (body length, body mass, percentage body fat and
percentage muscle mass), physical (pliancy, abdominal power, aerobic endurance and
anaerobic endurance) and motor (speed over 5 m and 10 m, agility and explosive
power) requirements. This consequently necessitates specific attention to be given to
the mentioned requirements. In spite of the fact that a few studies do exist that enter
into the requirements of the profile of netball players in different positions, as well as
into what the effect of a periodization programme is on anthropometric, physical and
motor requirements, voids do exist regarding the positional profile of 15 to 17 year old
netball players and as to what the effect is of a sport specific periodization programme
in the course of a season on 15 to 17 year old netball players.
In the light of the above–mentioned, this study was undertaken with the aim to:
1) Determine the requirements for 15 to 17 year old netball players;
2) Compile positional profile scales of netball specific requirement for 15 to 17 year old
players in the Tlokwe region;
3) Establish the effect of a sport specific periodization programme on anthropometric,
physical and motor requirements for 15 to 17 year old female netball players, of a
specific school in the Tlokwe region, in the course of a season.
96 players (28 goalkeepers, 44 centre court players and 24 defenders) between ages
15 and 17 years from two high schools in the North–West Province were used in the
study to determine positional differences. A group of only 22 player of one school was
exposed to a sport specific periodization programme for purposes of the study, since
the coach and players from only one school’s teams were prepared to participate in the
sport scientific intervention programme for the full duration of the netball season. The
afore–mentioned group was evaluated over a period of two years, namely prior to the start of the season (T1), after conclusion of the season once the sport specific
periodization programme was completed (T2), prior to the start of the season in the
subsequent year (T3) and after conclusion of the season without the sport specific being
followed. The data is processed on the basis of descriptive statistics. Furthermore, the
practical significance of test result changes between the respective groups and different
test sessions were compared using Cohen’s effect size.
Literature was consulted to determine whether specific requirements exist for netball
players and whether differences occur in the three positional groups. However, no
literature could be traced in which only netball specific requirements for 15 to 17 year
old players were focused on. The literature did indeed point out clear anthropometric
differences between the three positional groups, namely attacking, centre court and
defence players in club and elite netball players. The goalkeeper and defence players
are, according to literature, considerably taller and heavier than the centre court players.
Literature also indicated that differences do indeed occur regarding physical and motor
requirements. Centre court players are significantly faster and more agile than the
goalkeeper and defenders. However, there were components of which the differences
were not prominent concerning the three positional groups.
Where a specific positional profile of anthropometric, physical and motor requirements
for 15 to 17 year old female netball players was composed from available data of
players in the North–West Province, Tlokwe region, the results of the anthropometric
requirements indicated that body length showed a large significant difference between
the three positional groups, with defenders being the tallest, followed by goalkeepers,
and the centre court players being the shortest. Body mass also showed a medium
significant difference between goalkeepers and centre court players as well as between
centre court players and defence players. Goalkeepers were heavier than centre court
players, and defenders also showed a higher body mass than centre court players. The
other two variables, namely percentage fat and percentage muscle mass, only showed
small practically significant differences, in this group of netball players, between the test
sessions.
With the physical and motor requirements, results indicated that large practically
significant differences occurred in vertical jumping, 5 m speed, 10 m speed and agility between the groups. The general trend observed in the profiles was that the largest
significant differences occurred between goalkeepers and defence players on the one
hand and centre court players on the other. Vertical jump and speed showed a large
significant difference between goalkeepers and centre court players as well as between
centre court players and defenders, although the goalkeepers and defenders’ results
corresponded considerably. Other large significant differences occurred in the 10 m
speed as well as in 505–agility to the left between centre court players and defenders.
In summary it can be mentioned that the most and the largest significant differences
occurred between goalkeepers and centre court players as well as between defenders
and centre court players. Only one medium significant difference occurred between the
goalkeepers and defenders, which is ankle dorsiflexion and which can be ascribed to
injuries. From this it can be inferred that a positional profile can indeed be compiled for
the different positional groups in netball, but that the requirements of positional variables
between goalkeepers and defenders correspond largely and that the large difference
between the last–mentioned two groups occur when compared with those of the centre
court players of this specific group.
The results of the group of twenty–two players that were evaluated twice during the
course of both netball seasons indicate that the variable that showed a large significant
difference between T1 and T2, following the sport specific periodization program, was
body mass (inverted difference). Although there was no large significant difference, it
can clearly be deduced from the graphs presented in the study that a visible difference
(improvement) was observed in most of the variables. The variables that showed a
large practically significant difference with the training of the coach’s general
programme, were ankle dorsiflexion on the left, abdominal power and 5 m speed
(inverted effect). A number of variables indeed existed that also showed medium and
small significant differences during the course of both seasons, but it will not be
mentioned here.
A number of shortcomings and recommendations did indeed come to the fore during
and after the course of the study. It should, however, be borne in mind that such a
structured periodization programme is very important for the development of netball
potential. / Thesis (Ph.D. (Human Movement Science))--North-West University, Potchefstroom Campus, 2011.
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Sportspesifieke inoefening en antropometriese, fisieke en motoriese vereistes van 15– tot 17–jaar oue vroulike netbalspelers / Y. WillemseWillemse, Yolandi January 2010 (has links)
In the light of the facts given in literature it is evident that players in the game of netball
need to meet specific anthropometric (body length, body mass, percentage body fat and
percentage muscle mass), physical (pliancy, abdominal power, aerobic endurance and
anaerobic endurance) and motor (speed over 5 m and 10 m, agility and explosive
power) requirements. This consequently necessitates specific attention to be given to
the mentioned requirements. In spite of the fact that a few studies do exist that enter
into the requirements of the profile of netball players in different positions, as well as
into what the effect of a periodization programme is on anthropometric, physical and
motor requirements, voids do exist regarding the positional profile of 15 to 17 year old
netball players and as to what the effect is of a sport specific periodization programme
in the course of a season on 15 to 17 year old netball players.
In the light of the above–mentioned, this study was undertaken with the aim to:
1) Determine the requirements for 15 to 17 year old netball players;
2) Compile positional profile scales of netball specific requirement for 15 to 17 year old
players in the Tlokwe region;
3) Establish the effect of a sport specific periodization programme on anthropometric,
physical and motor requirements for 15 to 17 year old female netball players, of a
specific school in the Tlokwe region, in the course of a season.
96 players (28 goalkeepers, 44 centre court players and 24 defenders) between ages
15 and 17 years from two high schools in the North–West Province were used in the
study to determine positional differences. A group of only 22 player of one school was
exposed to a sport specific periodization programme for purposes of the study, since
the coach and players from only one school’s teams were prepared to participate in the
sport scientific intervention programme for the full duration of the netball season. The
afore–mentioned group was evaluated over a period of two years, namely prior to the start of the season (T1), after conclusion of the season once the sport specific
periodization programme was completed (T2), prior to the start of the season in the
subsequent year (T3) and after conclusion of the season without the sport specific being
followed. The data is processed on the basis of descriptive statistics. Furthermore, the
practical significance of test result changes between the respective groups and different
test sessions were compared using Cohen’s effect size.
Literature was consulted to determine whether specific requirements exist for netball
players and whether differences occur in the three positional groups. However, no
literature could be traced in which only netball specific requirements for 15 to 17 year
old players were focused on. The literature did indeed point out clear anthropometric
differences between the three positional groups, namely attacking, centre court and
defence players in club and elite netball players. The goalkeeper and defence players
are, according to literature, considerably taller and heavier than the centre court players.
Literature also indicated that differences do indeed occur regarding physical and motor
requirements. Centre court players are significantly faster and more agile than the
goalkeeper and defenders. However, there were components of which the differences
were not prominent concerning the three positional groups.
Where a specific positional profile of anthropometric, physical and motor requirements
for 15 to 17 year old female netball players was composed from available data of
players in the North–West Province, Tlokwe region, the results of the anthropometric
requirements indicated that body length showed a large significant difference between
the three positional groups, with defenders being the tallest, followed by goalkeepers,
and the centre court players being the shortest. Body mass also showed a medium
significant difference between goalkeepers and centre court players as well as between
centre court players and defence players. Goalkeepers were heavier than centre court
players, and defenders also showed a higher body mass than centre court players. The
other two variables, namely percentage fat and percentage muscle mass, only showed
small practically significant differences, in this group of netball players, between the test
sessions.
With the physical and motor requirements, results indicated that large practically
significant differences occurred in vertical jumping, 5 m speed, 10 m speed and agility between the groups. The general trend observed in the profiles was that the largest
significant differences occurred between goalkeepers and defence players on the one
hand and centre court players on the other. Vertical jump and speed showed a large
significant difference between goalkeepers and centre court players as well as between
centre court players and defenders, although the goalkeepers and defenders’ results
corresponded considerably. Other large significant differences occurred in the 10 m
speed as well as in 505–agility to the left between centre court players and defenders.
In summary it can be mentioned that the most and the largest significant differences
occurred between goalkeepers and centre court players as well as between defenders
and centre court players. Only one medium significant difference occurred between the
goalkeepers and defenders, which is ankle dorsiflexion and which can be ascribed to
injuries. From this it can be inferred that a positional profile can indeed be compiled for
the different positional groups in netball, but that the requirements of positional variables
between goalkeepers and defenders correspond largely and that the large difference
between the last–mentioned two groups occur when compared with those of the centre
court players of this specific group.
The results of the group of twenty–two players that were evaluated twice during the
course of both netball seasons indicate that the variable that showed a large significant
difference between T1 and T2, following the sport specific periodization program, was
body mass (inverted difference). Although there was no large significant difference, it
can clearly be deduced from the graphs presented in the study that a visible difference
(improvement) was observed in most of the variables. The variables that showed a
large practically significant difference with the training of the coach’s general
programme, were ankle dorsiflexion on the left, abdominal power and 5 m speed
(inverted effect). A number of variables indeed existed that also showed medium and
small significant differences during the course of both seasons, but it will not be
mentioned here.
A number of shortcomings and recommendations did indeed come to the fore during
and after the course of the study. It should, however, be borne in mind that such a
structured periodization programme is very important for the development of netball
potential. / Thesis (Ph.D. (Human Movement Science))--North-West University, Potchefstroom Campus, 2011.
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