Comparison of leg dominance and fatigue state on lower extremity kinematics during cutting manoeuvres in male soccer players
- Authors: Nienaber, Madeleine
- Date: 2019
- Subjects: Human mechanics , Kinematics Kinesiology Sports injuries Soccer players -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/42880 , vital:36702
- Description: Soccer is one of the most popular sports played in South Africa and around the world. Soccer is a high intensity, semi-contact sport which is associated with an increased prevalence of injuries, especially to the lower extremities. Central and neuromuscular fatigue is believed to cause changes to kinetic and kinematic patterns of soccer players which may increase the risk for injuries, specifically related to the anterior cruciate ligament (ACL). To investigate the effects of fatigue on knee joint kinematics during the stance phase of a cutting manoeuvre of the dominant and non-dominant legs. A quantitative approach, more specifically, an experimental study design was adopte and a quasi-experimental study design was selected. A ‘within-participants post-test only design’ was used, which is also known as a ‘repeated measures design’ because all participants were ‘repeatedly’ measured under each experimental condition. Due to the non-randomization of the quasi-experimental design, non-probability sampling was utilized to sample the population group for the proposed study. A total of 13 male soccer players volunteered for the study. The participants had the following characteristics (mean ± SD): age 22.15 ± 2.77 years; height 169.64 ± 5.75 cm and weight 64.60 ± 7.04 kg. Non-significant differences within hip joint kinematics were observed between the dominant and non-dominant legs in a non-fatigued state in all three planes of motion (F = 0.61, p = 0.55). Similar kinematic characteristics were observed for the knee joint (F = 1.25, p = 0.48) and the ankle joint (F = 3.33, p = 0.64). Non-significant differences were also observed during the fatigued state in all three planes of motion for the hip joints (F = 8.98, p = 0.72), knee joints (F = 5.21, p = 0.41) and ankle joints (F = 0.21, p = 0.12). Peak vertical forces were however significantly different between the fatigued state compared to the non-fatigued state during the cutting manoeuvre (F = 23.51, p = 0.035), thereby indicating that neuromuscular fatigue may influence landing forces on impact during a directional change. The effect of leg dominance did not have a statistically significant impact on any kinematic measures as well as the interactions between fatigue and non-fatigue trials were also not observed for any of the kinematic parameters. Several initial contact and peak stance–phase lower limb-joint rotations were influenced by fatigue during the execution of the sub-maximal 60° cutting manoeuvre. The main effect of fatigue produced an increase in knee internal rotation and hip abduction and a decrease in peak knee abduction angles compared to non-fatigue, but they were not statistically significant. Significant differences were found between dominant and non-dominant legs as well as between fatigue and non-fatigue with ankle pronation (p=0.007) and ankle external rotation (p=0.033). Knee abduction angle during cutting (p=0.061) also showed an effect even though not statistically significant. The purpose was to examine the combined effects of leg dominance and fatigue on lower-limb biomechanics during a sub-maximal 60° cutting manoeuvre. The conclusion of the present study related to limb dominance was that no statistically significant differences were evident for any of the dependent variables (limb dominance; fatigue state) related to the independent variables (i.e. joint [hip, knee, ankle], contact time, ground reaction however, between-subject fatigue variations that is large enough could negatively impact the biomechanical data comparisons. Future research should target specific locations of fatigue within a general fatigue paradigm and develop standardized tasks to achieve this.
- Full Text:
- Date Issued: 2019
- Authors: Nienaber, Madeleine
- Date: 2019
- Subjects: Human mechanics , Kinematics Kinesiology Sports injuries Soccer players -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/42880 , vital:36702
- Description: Soccer is one of the most popular sports played in South Africa and around the world. Soccer is a high intensity, semi-contact sport which is associated with an increased prevalence of injuries, especially to the lower extremities. Central and neuromuscular fatigue is believed to cause changes to kinetic and kinematic patterns of soccer players which may increase the risk for injuries, specifically related to the anterior cruciate ligament (ACL). To investigate the effects of fatigue on knee joint kinematics during the stance phase of a cutting manoeuvre of the dominant and non-dominant legs. A quantitative approach, more specifically, an experimental study design was adopte and a quasi-experimental study design was selected. A ‘within-participants post-test only design’ was used, which is also known as a ‘repeated measures design’ because all participants were ‘repeatedly’ measured under each experimental condition. Due to the non-randomization of the quasi-experimental design, non-probability sampling was utilized to sample the population group for the proposed study. A total of 13 male soccer players volunteered for the study. The participants had the following characteristics (mean ± SD): age 22.15 ± 2.77 years; height 169.64 ± 5.75 cm and weight 64.60 ± 7.04 kg. Non-significant differences within hip joint kinematics were observed between the dominant and non-dominant legs in a non-fatigued state in all three planes of motion (F = 0.61, p = 0.55). Similar kinematic characteristics were observed for the knee joint (F = 1.25, p = 0.48) and the ankle joint (F = 3.33, p = 0.64). Non-significant differences were also observed during the fatigued state in all three planes of motion for the hip joints (F = 8.98, p = 0.72), knee joints (F = 5.21, p = 0.41) and ankle joints (F = 0.21, p = 0.12). Peak vertical forces were however significantly different between the fatigued state compared to the non-fatigued state during the cutting manoeuvre (F = 23.51, p = 0.035), thereby indicating that neuromuscular fatigue may influence landing forces on impact during a directional change. The effect of leg dominance did not have a statistically significant impact on any kinematic measures as well as the interactions between fatigue and non-fatigue trials were also not observed for any of the kinematic parameters. Several initial contact and peak stance–phase lower limb-joint rotations were influenced by fatigue during the execution of the sub-maximal 60° cutting manoeuvre. The main effect of fatigue produced an increase in knee internal rotation and hip abduction and a decrease in peak knee abduction angles compared to non-fatigue, but they were not statistically significant. Significant differences were found between dominant and non-dominant legs as well as between fatigue and non-fatigue with ankle pronation (p=0.007) and ankle external rotation (p=0.033). Knee abduction angle during cutting (p=0.061) also showed an effect even though not statistically significant. The purpose was to examine the combined effects of leg dominance and fatigue on lower-limb biomechanics during a sub-maximal 60° cutting manoeuvre. The conclusion of the present study related to limb dominance was that no statistically significant differences were evident for any of the dependent variables (limb dominance; fatigue state) related to the independent variables (i.e. joint [hip, knee, ankle], contact time, ground reaction however, between-subject fatigue variations that is large enough could negatively impact the biomechanical data comparisons. Future research should target specific locations of fatigue within a general fatigue paradigm and develop standardized tasks to achieve this.
- Full Text:
- Date Issued: 2019
Plantar pressure and impulse profiles of students from a South African university
- Authors: Kramer, Mark
- Date: 2012
- Subjects: Human mechanics , Foot -- Movements , Joints -- ange of motion , eng
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:10095 , http://hdl.handle.net/10948/d1010606 , Human mechanics , Foot -- Movements , Joints -- ange of motion
- Description: Most activities of daily living and numerous modes of physical activity incorporate some form of ambulation, of which the foot and ankle constitute the first link in the kinetic chain. A change in foot or ankle structure may therefore have subsequent effects on the superincumbent joints of the human body such as the knee, hip and lower back. Plantar pressure and impulse measurements can therefore provide greater insight into the mechanics of the foot under load-bearing conditions with regards to the areas and regions of the foot that exhibit the largest pressure values and impulse figures. Hence, it is of importance to establish normative data so as to obtain a frame of reference to identify those individuals that fall outside these norms and may exhibit a larger probability of injury. Aim and Objectives: The primary aim was to identify and compare the plantar pressure distribution patterns and impulse values of students of a South African university of different gender and race groups. To realise this aim two specific objectives were set. The first was to determine whether height, weight, body mass index (BMI), gender, race, and the level of physical activity were related to the pressure and impulse values obtained, and the second was to generate reference tables from the normative data gathered. Method: The RS Footscan system was used to measure the pressure and impulse values of the foot. The characteristics that were analysed were height, weight, body mass index and the level of physical activity of the participant and their respective association with plantar pressure and impulse values obtained. This information was then used to establish normative data. A quasi-experimental study design utilising convenience sampling was implemented as the intention was to investigate as single instance in as natural a manner as possible. Convenience sampling was used with predefined inclusion and exclusion criteria. A total of 180 participants were utilised in this study and were subdivided as follows: Gender: Males (n = 90); Females (n = 90); Race: African black (n = 60); white (n = 60) and coloured (n = 60). Each race group therefore comprised of 30 males and 30 females respectively. The anthropometric profile of participants was as follows: Age (S.D.) = 22.21 (S.D. ± 2.93) years; Height (S.D.) = 169.69 (S.D. ± 8.91) cm; Weight (S.D.) = 66.97 (S.D. ± 12.01) kg; BMI (S.D.) = 23.16 (S.D. ± 3.15) kg/m2. Participants were asked to complete a questionnaire prior to testing that would identify all exclusion criteria consisting of: the presence of foot pain or deformity, acute lower extremity trauma, lower extremity surgery, exhibited problems of performance including eye, ear or cognitive impairment, diabetes mellitus or other neurological neuropathy, or the use of walking aids. Anthropometric measurements were then taken for those participants that qualified for the study. Participants were required to perform approximately five warm-up trials to familiarise themselves with the testing equipment before testing commenced. A total of ten successful trails were subsequently recorded for each participant, with three footprints being recorded per trial on the pressure platform, thereby comprising 30 footprints (15 left foot and 15 right foot) per participant that were analysed regarding pressure and impulse values. The two-step gait initiation protocol was implemented which was proven to be a valid and reliable means of assessing gait. Participants were instructed to walk at a comfortable walking speed between 1.19 – 1.60 m/s to ensure conformity between all participants as between-trial gait velocities were proven to be significantly variable. The foot was subdivided into ten anatomical areas focusing on the great toe, lesser toes, metatarsal 1, metatarsal 2, metatarsal 3, metatarsal 4, metatarsal 5, midfoot, medial heel and lateral heel. These ten areas were then grouped into one of three regions, namely the forefoot region (great toe, lesser toes, and all five metatarsal head areas), midfoot region (midfoot area), and rearfoot/heel region (medial and lateral heel areas). Once all relevant data was gathered, corrected and analysed it was used to establish normative data tables pertaining to the various gender and race groups. Results: Of the ten individual pressure and impulse areas, the second and third metatarsal heads demonstrated the highest mean peak pressure and impulse values. Once grouped into one of the three regions, the heel region was ascribed with the largest impulse and pressure values. It was established that statistically and practically significant racial pressure differences were apparent in the left and right forefoot and midfoot regions, with black and coloured individuals yielding the highest values, whereas white participants yielded the lowest. The same was true with regards to impulse figures in that both statistical and practical significant levels were established in the forefoot and midfoot regions. Black and coloured participants exhibited larger impulse values than the white participants. The level of physical activity was found to be associated with both pressure and impulse values over the various regions of the foot. Black individuals that were largely inactive as well as moderately active coloured participants yielded the highest pressure and impulse values, which were found to be statistically and practically significant over the forefoot regions. Conversely, white participants of all physical activity levels as well as coloured participants of both low and high physical activity levels exhibited the lowest pressure values over the forefoot region, which were also found to be statistically and practically significant. The anthropometric variables of height, weight and BMI were found to relate statistically to pressure and impulse values under the various regions of the foot, but none were found to be of any practical significance (r < .30). Conclusion: It was clearly established that both gender and race specific differences existed regarding plantar pressure and impulse values of the normal foot. Plantar pressure and impulse values were also associated with the level of physical activity of the individual, thereby indicating that the level of physical activity could be a contributing factor to altered pressure and impulse values. Anthropometric variables such as height, weight and BMI could not solely account for the variances observed in pressure and impulse. Further research is required to determine whether pressure or impulse values above or below those obtained predispose an individual to injury and to contrast between various activity or sporting codes and the effect of these on plantar pressure and impulse figures. Finally, from the collected data one was able to establish reference tables for the specific gender and race groups for both plantar pressure and impulse values. This enables one to classify individuals based on the pressure and impulse values generated.
- Full Text:
- Date Issued: 2012
- Authors: Kramer, Mark
- Date: 2012
- Subjects: Human mechanics , Foot -- Movements , Joints -- ange of motion , eng
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:10095 , http://hdl.handle.net/10948/d1010606 , Human mechanics , Foot -- Movements , Joints -- ange of motion
- Description: Most activities of daily living and numerous modes of physical activity incorporate some form of ambulation, of which the foot and ankle constitute the first link in the kinetic chain. A change in foot or ankle structure may therefore have subsequent effects on the superincumbent joints of the human body such as the knee, hip and lower back. Plantar pressure and impulse measurements can therefore provide greater insight into the mechanics of the foot under load-bearing conditions with regards to the areas and regions of the foot that exhibit the largest pressure values and impulse figures. Hence, it is of importance to establish normative data so as to obtain a frame of reference to identify those individuals that fall outside these norms and may exhibit a larger probability of injury. Aim and Objectives: The primary aim was to identify and compare the plantar pressure distribution patterns and impulse values of students of a South African university of different gender and race groups. To realise this aim two specific objectives were set. The first was to determine whether height, weight, body mass index (BMI), gender, race, and the level of physical activity were related to the pressure and impulse values obtained, and the second was to generate reference tables from the normative data gathered. Method: The RS Footscan system was used to measure the pressure and impulse values of the foot. The characteristics that were analysed were height, weight, body mass index and the level of physical activity of the participant and their respective association with plantar pressure and impulse values obtained. This information was then used to establish normative data. A quasi-experimental study design utilising convenience sampling was implemented as the intention was to investigate as single instance in as natural a manner as possible. Convenience sampling was used with predefined inclusion and exclusion criteria. A total of 180 participants were utilised in this study and were subdivided as follows: Gender: Males (n = 90); Females (n = 90); Race: African black (n = 60); white (n = 60) and coloured (n = 60). Each race group therefore comprised of 30 males and 30 females respectively. The anthropometric profile of participants was as follows: Age (S.D.) = 22.21 (S.D. ± 2.93) years; Height (S.D.) = 169.69 (S.D. ± 8.91) cm; Weight (S.D.) = 66.97 (S.D. ± 12.01) kg; BMI (S.D.) = 23.16 (S.D. ± 3.15) kg/m2. Participants were asked to complete a questionnaire prior to testing that would identify all exclusion criteria consisting of: the presence of foot pain or deformity, acute lower extremity trauma, lower extremity surgery, exhibited problems of performance including eye, ear or cognitive impairment, diabetes mellitus or other neurological neuropathy, or the use of walking aids. Anthropometric measurements were then taken for those participants that qualified for the study. Participants were required to perform approximately five warm-up trials to familiarise themselves with the testing equipment before testing commenced. A total of ten successful trails were subsequently recorded for each participant, with three footprints being recorded per trial on the pressure platform, thereby comprising 30 footprints (15 left foot and 15 right foot) per participant that were analysed regarding pressure and impulse values. The two-step gait initiation protocol was implemented which was proven to be a valid and reliable means of assessing gait. Participants were instructed to walk at a comfortable walking speed between 1.19 – 1.60 m/s to ensure conformity between all participants as between-trial gait velocities were proven to be significantly variable. The foot was subdivided into ten anatomical areas focusing on the great toe, lesser toes, metatarsal 1, metatarsal 2, metatarsal 3, metatarsal 4, metatarsal 5, midfoot, medial heel and lateral heel. These ten areas were then grouped into one of three regions, namely the forefoot region (great toe, lesser toes, and all five metatarsal head areas), midfoot region (midfoot area), and rearfoot/heel region (medial and lateral heel areas). Once all relevant data was gathered, corrected and analysed it was used to establish normative data tables pertaining to the various gender and race groups. Results: Of the ten individual pressure and impulse areas, the second and third metatarsal heads demonstrated the highest mean peak pressure and impulse values. Once grouped into one of the three regions, the heel region was ascribed with the largest impulse and pressure values. It was established that statistically and practically significant racial pressure differences were apparent in the left and right forefoot and midfoot regions, with black and coloured individuals yielding the highest values, whereas white participants yielded the lowest. The same was true with regards to impulse figures in that both statistical and practical significant levels were established in the forefoot and midfoot regions. Black and coloured participants exhibited larger impulse values than the white participants. The level of physical activity was found to be associated with both pressure and impulse values over the various regions of the foot. Black individuals that were largely inactive as well as moderately active coloured participants yielded the highest pressure and impulse values, which were found to be statistically and practically significant over the forefoot regions. Conversely, white participants of all physical activity levels as well as coloured participants of both low and high physical activity levels exhibited the lowest pressure values over the forefoot region, which were also found to be statistically and practically significant. The anthropometric variables of height, weight and BMI were found to relate statistically to pressure and impulse values under the various regions of the foot, but none were found to be of any practical significance (r < .30). Conclusion: It was clearly established that both gender and race specific differences existed regarding plantar pressure and impulse values of the normal foot. Plantar pressure and impulse values were also associated with the level of physical activity of the individual, thereby indicating that the level of physical activity could be a contributing factor to altered pressure and impulse values. Anthropometric variables such as height, weight and BMI could not solely account for the variances observed in pressure and impulse. Further research is required to determine whether pressure or impulse values above or below those obtained predispose an individual to injury and to contrast between various activity or sporting codes and the effect of these on plantar pressure and impulse figures. Finally, from the collected data one was able to establish reference tables for the specific gender and race groups for both plantar pressure and impulse values. This enables one to classify individuals based on the pressure and impulse values generated.
- Full Text:
- Date Issued: 2012
Plantar force differences before and after an ultra-endurance event
- Authors: Sims, Gwenivere
- Date: 2011
- Subjects: Human mechanics , Foot -- Abnormalities , Foot surgery
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:10101 , http://hdl.handle.net/10948/d1012795 , Human mechanics , Foot -- Abnormalities , Foot surgery
- Description: The aim of this study was to determine the pre- and post-plantar force differences of athletes competing in an ultra-endurance event. The study was exploratory and quasi-experimental in nature and utilized a quantitative approach. A Quasi-experimental, one group pretest, posttest design was used. The study involved 84 participants selected by means of convenient sampling from a total of 1552 participants. The equipment used for data collection was the RS Footscan®, stadiometer and a weight scale. Differences between the plantar forces before and after the competition were significant for the sample group, indicating higher forces before the competition (t = -3.62, p = 0.001, d = 0.40). Gender, and novice and expert groupings had no significant effect on the plantar forces (t = 1.43, p = 0.155 and t = 0.21, p = 0.837) respectively. Gender groups had large significant differences between the left and right forefoot (t = 3.90, p = 0.000) and the heel (t = 3.54, p = 0.001), before the competition, but this difference was reduced after the competition from large to moderate significance for the forefoot and the heel (t = 2.84, p = 0.006 and t = 2.99 and p = 0.004) respectively. Lower forces after the ultra-endurance event may indicate compensation due to overuse; with less muscle contraction to control foot roll over for force distribution. Favouring of the right foot for weight bearing changed after the event with smaller differences, which could indicate increase loading of the left feet, which may result in injury. The number of females included in this study was relatively few and therefore the effect of gender in respect of plantar foot force exerted should be interpreted with caution. The novices recorded higher forces in the forefoot, after the competition. Similar results were found in other studies that reported increased pressures under the forefoot after long distance running. The latter findings may suggest that novices have a higher chance for overuse injury.
- Full Text:
- Date Issued: 2011
- Authors: Sims, Gwenivere
- Date: 2011
- Subjects: Human mechanics , Foot -- Abnormalities , Foot surgery
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:10101 , http://hdl.handle.net/10948/d1012795 , Human mechanics , Foot -- Abnormalities , Foot surgery
- Description: The aim of this study was to determine the pre- and post-plantar force differences of athletes competing in an ultra-endurance event. The study was exploratory and quasi-experimental in nature and utilized a quantitative approach. A Quasi-experimental, one group pretest, posttest design was used. The study involved 84 participants selected by means of convenient sampling from a total of 1552 participants. The equipment used for data collection was the RS Footscan®, stadiometer and a weight scale. Differences between the plantar forces before and after the competition were significant for the sample group, indicating higher forces before the competition (t = -3.62, p = 0.001, d = 0.40). Gender, and novice and expert groupings had no significant effect on the plantar forces (t = 1.43, p = 0.155 and t = 0.21, p = 0.837) respectively. Gender groups had large significant differences between the left and right forefoot (t = 3.90, p = 0.000) and the heel (t = 3.54, p = 0.001), before the competition, but this difference was reduced after the competition from large to moderate significance for the forefoot and the heel (t = 2.84, p = 0.006 and t = 2.99 and p = 0.004) respectively. Lower forces after the ultra-endurance event may indicate compensation due to overuse; with less muscle contraction to control foot roll over for force distribution. Favouring of the right foot for weight bearing changed after the event with smaller differences, which could indicate increase loading of the left feet, which may result in injury. The number of females included in this study was relatively few and therefore the effect of gender in respect of plantar foot force exerted should be interpreted with caution. The novices recorded higher forces in the forefoot, after the competition. Similar results were found in other studies that reported increased pressures under the forefoot after long distance running. The latter findings may suggest that novices have a higher chance for overuse injury.
- Full Text:
- Date Issued: 2011
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