Analysis of the backpack loading efects on the human gait

Gait is a simple activity of daily life and one of the main abilities of the human being. Often during leisure, labour and sports activities, loads are carried over (e.g. backpack) during gait. These circumstantial loads can generate instability and increase biomechanicalstress over the human tissues and systems, especially on the locomotor, balance and postural regulation systems. According to Wearing (2006), subjects that carry a transitory or intermittent load will be able to find relatively efficient solutions to compensate its effects.info:eu-repo/semantics/publishedVersio

Nutrient Intake, Performance, and Body Composition in Preseason Wrestlers

BACKGROUND: College athletes, especially in weight class sports, often experience energy deficits. Weight class sports such as wrestling are at greatest risk for deficiencies, and little is known about the relationships between body composition, nutrient intake, and performance in these athletes. OBJECTIVES: The purposes of this study were to quantify macronutrient and micronutrient intake of pre-season male collegiate wrestlers and compare to recommendations, and examine relationships among nutritional intakes, body composition, and performance measurements of strength, anaerobic, and aerobic capacity. METHODS: Male Division I wrestlers (n=11, mean ± SD age: 21.3±1.7 years, wrestling experience: 14.9±2.5 years) were recruited during preseason. Nutrient intake was collected from a 3-day food diary. A 7-site skinfold assessment determined fat-free mass (FFM) to estimate total energy expenditure. Isokinetic and isometric strength was evaluated by a Biodex dynamometer. Aerobic and anaerobic capacity were tested on a stationary cycle ergometer. RESULTS: Eight of eleven wrestlers were energy deficient based on estimated needs. Mean intake for 4 micronutrients fell below the RDA. Significant correlations were found between energy and macronutrient intake, and strength and anaerobic performance variables (r=0.603 – 0.902, p=0.0001 – 0.05). However, after accounting for FFM, these relationships were no longer significant. CONCLUSIONS: Nutrient intake in tandem with body composition effect performance for weight class athletes. Maintaining high FFM, especially during the competition season, may be advantageous for wrestling performance. Nutrient intake and body composition should be monitored so coaches and health professionals can create individualized recommendations to help athletes optimize performance

Recovery of Muscle Function Following Strength Training in Rowers

Strength training using free weights is performed by athletes in many sports as a means of enhancing performance. However, there is a dearth of research investigating the acute impact of bouts of this form of strength training on muscle function, which closely mimics the athletes’ sport or event. High forces are produced during a rowing race and subsequently strength training forms an integral part of the overall training programme for rowers. However, there is little documented evidence regarding the strength and conditioning practices occurring in rowing. Therefore the aims of this thesis were to investigate and draw conclusions regarding the strength and conditioning practices occurring within British rowing and to evaluate the impact of typical bouts of strength training on muscle function in rowers. To investigate the strength and conditioning practices within British rowing a questionnaire was completed by 32 coaches and semi-structured interviews were undertaken with two coaches of elite rowers (study 1). Information from both sources indicated that rowers performed two to three strength training sessions per week, involving Olympic lifting and multi-joint free weight strength exercises, performed across multiple sets with low to moderate repetition ranges. Physical testing most commonly involved assessment of cardiovascular endurance, muscular power and strength. Twenty four hours of recovery were generally afforded between strength training and intensive rowing training while longer periods were permitted before rowing races (> 48 h). Prior to the intervention studies, the reproducibility of subsequently assessed measures was assessed using trained rowers (study 2). Typical error (%) was low for 2000 m mean power (2.4 %), and low to moderate for the assessments of strength and power (3.0-5.9 %). Measures of peak blood lactate (11.5 %), creatine kinase (21.0 %) and surface electromyography (11.1-44.8 %, across various sites) demonstrated greater variability similar to previous studies. For studies 3 and 4, trained rowers performed 250 m and 2000 m rowing tests respectively, alongside various measures of muscle function before and after an acute bout of free weight multi-joint strength training (ST). For both studies, increases in perceived muscle soreness and CK indicated that muscle damage was present after ST for 24-48 h. Maximal power generating ability was decreased in both studies as evidenced by decrements in the 250 m test, power strokes, and jump height. However, in study 4, 2000 m rowing time was unaffected, leading to the conclusion that the specific muscle function required for the power tests was affected through damage to type II muscle fibres. Findings from study 1 indicated that rowers commonly perform strength training three times per week; therefore study 5 investigated the impact of this weekly frequency of strength training on muscle function. Twenty four hours after three bouts of ST within a five day period, trained rowers experienced significant decreases in maximal voluntary contraction, jump height and power stroke tests as well as increases in CK and soreness; however as with study 4, 2000m performance was unaffected. Trends for decreases in peak lactate and anaerobic energy liberation (p < 0.10, Effect Size = 0.40-0.56) were present alongside significant increases in EMG at three sites during the post-ST 2000 m test. These findings suggest a decreased utilisation of the anaerobic capacity coupled with increased central motor drive suggesting a change in muscular recruitment patterns during the follow up 2000 m rowing test. It would appear that following extensive strength training, physiological processes were adapted during subsequent rowing exercise, to compensate for the loss in higher threshold muscle fibre function, in order to affect the same level of rowing performance achieved in the rested state. These findings might suggest that participants operated within a physiological reserve and/or that multiple-exercise-regulation-algorithms exist with which a similar exercise performance can be achieved

Relationship of Force Variables to Vertical Jumps Performance

The isometric mid-thigh pull (IMTP) has been cited often in the scientific literature; however, there is still a lack of agreement as to the ideal body position used during this test, and how body position impacts the relationship between IMTP performance and dynamic performance. Thus, one aim of this dissertation was to compare two different IMTP positions and correlate the kinetic outputs from each position to vertical jump (VJ) performance. Another purpose of this dissertation was analyze which method of data normalization for IMTP force variables best correlates to squat jump (SJ) and countermovement jump (CMJ) performance. In the first study, subjects presented higher force outputs for an upright position (hip angles 145°, knee 125°) when compared to a bent position (hip angles 125°, knee 125°). However, there were no statistical differences among correlations from the two positions when correlating to VJ performance. Thus, we suggest that the upright position should be the one used for research and monitoring due to higher force values presented. The second part of this study was to compare correlations from non-normalized and normalized data from the IMTP to SJ and CMJ. Besides non-normalized data, five common methods of normalization were used – subtracting the body mass force, dividing the forces per body mass, allometric scale, scaling by height (Ford’s scale) and scaling by Sinclair coefficient value. In general, higher value correlations were presented with the non-normalized methods for both jumps – SJ and CMJ. Therefore, when using IMTP data to correlate with VJ performance, there is no need to normalize the data

Astronaut training manual

Scientific information from previous space flights, space medicine, exercise physiology, and sports medicine was used to prepare a physical fitness manual suitable for use by members of the NASA astronaut population. A variety of scientifically valid exercise programs and activities suitable for the development of physical fitness are provided. Programs, activities, and supportive scientific data are presented in a concise, easy to read format so as to permit the user to select his or her mode of training with confidence and devote time previously spent experimenting with training routines to preparation for space flight. The programs and activities included were tested and shown to be effective and enjoyable

Recovery of muscle function following strength training in rowers

Strength training using free weights is performed by athletes in many sports as a means of enhancing performance. However, there is a dearth of research investigating the acute impact of bouts of this form of strength training on muscle function, which closely mimics the athletes’ sport or event. High forces are produced during a rowing race and subsequently strength training forms an integral part of the overall training programme for rowers. However, there is little documented evidence regarding the strength and conditioning practices occurring in rowing. Therefore the aims of this thesis were to investigate and draw conclusions regarding the strength and conditioning practices occurring within British rowing and to evaluate the impact of typical bouts of strength training on muscle function in rowers. To investigate the strength and conditioning practices within British rowing a questionnaire was completed by 32 coaches and semi-structured interviews were undertaken with two coaches of elite rowers (study 1). Information from both sources indicated that rowers performed two to three strength training sessions per week, involving Olympic lifting and multi-joint free weight strength exercises, performed across multiple sets with low to moderate repetition ranges. Physical testing most commonly involved assessment of cardiovascular endurance, muscular power and strength. Twenty four hours of recovery were generally afforded between strength training and intensive rowing training while longer periods were permitted before rowing races (> 48 h). Prior to the intervention studies, the reproducibility of subsequently assessed measures was assessed using trained rowers (study 2). Typical error (%) was low for 2000 m mean power (2.4 %), and low to moderate for the assessments of strength and power (3.0-5.9 %). Measures of peak blood lactate (11.5 %), creatine kinase (21.0 %) and surface electromyography (11.1-44.8 %, across various sites) demonstrated greater variability similar to previous studies. For studies 3 and 4, trained rowers performed 250 m and 2000 m rowing tests respectively, alongside various measures of muscle function before and after an acute bout of free weight multi-joint strength training (ST). For both studies, increases in perceived muscle soreness and CK indicated that muscle damage was present after ST for 24-48 h. Maximal power generating ability was decreased in both studies as evidenced by decrements in the 250 m test, power strokes, and jump height. However, in study 4, 2000 m rowing time was unaffected, leading to the conclusion that the specific muscle function required for the power tests was affected through damage to type II muscle fibres. Findings from study 1 indicated that rowers commonly perform strength training three times per week; therefore study 5 investigated the impact of this weekly frequency of strength training on muscle function. Twenty four hours after three bouts of ST within a five day period, trained rowers experienced significant decreases in maximal voluntary contraction, jump height and power stroke tests as well as increases in CK and soreness; however as with study 4, 2000m performance was unaffected. Trends for decreases in peak lactate and anaerobic energy liberation (p < 0.10, Effect Size = 0.40-0.56) were present alongside significant increases in EMG at three sites during the post-ST 2000 m test. These findings suggest a decreased utilisation of the anaerobic capacity coupled with increased central motor drive suggesting a change in muscular recruitment patterns during the follow up 2000 m rowing test. It would appear that following extensive strength training, physiological processes were adapted during subsequent rowing exercise, to compensate for the loss in higher threshold muscle fibre function, in order to affect the same level of rowing performance achieved in the rested state. These findings might suggest that participants operated within a physiological reserve and/or that multiple-exercise-regulation-algorithms exist with which a similar exercise performance can be achieved.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Recovery of muscle function following strength training in rowers

Strength training using free weights is performed by athletes in many sports as a means of enhancing performance. However, there is a dearth of research investigating the acute impact of bouts of this form of strength training on muscle function, which closely mimics the athletes’ sport or event. High forces are produced during a rowing race and subsequently strength training forms an integral part of the overall training programme for rowers. However, there is little documented evidence regarding the strength and conditioning practices occurring in rowing. Therefore the aims of this thesis were to investigate and draw conclusions regarding the strength and conditioning practices occurring within British rowing and to evaluate the impact of typical bouts of strength training on muscle function in rowers. To investigate the strength and conditioning practices within British rowing a questionnaire was completed by 32 coaches and semi-structured interviews were undertaken with two coaches of elite rowers (study 1). Information from both sources indicated that rowers performed two to three strength training sessions per week, involving Olympic lifting and multi-joint free weight strength exercises, performed across multiple sets with low to moderate repetition ranges. Physical testing most commonly involved assessment of cardiovascular endurance, muscular power and strength. Twenty four hours of recovery were generally afforded between strength training and intensive rowing training while longer periods were permitted before rowing races (> 48 h). Prior to the intervention studies, the reproducibility of subsequently assessed measures was assessed using trained rowers (study 2). Typical error (%) was low for 2000 m mean power (2.4 %), and low to moderate for the assessments of strength and power (3.0-5.9 %). Measures of peak blood lactate (11.5 %), creatine kinase (21.0 %) and surface electromyography (11.1-44.8 %, across various sites) demonstrated greater variability similar to previous studies. For studies 3 and 4, trained rowers performed 250 m and 2000 m rowing tests respectively, alongside various measures of muscle function before and after an acute bout of free weight multi-joint strength training (ST). For both studies, increases in perceived muscle soreness and CK indicated that muscle damage was present after ST for 24-48 h. Maximal power generating ability was decreased in both studies as evidenced by decrements in the 250 m test, power strokes, and jump height. However, in study 4, 2000 m rowing time was unaffected, leading to the conclusion that the specific muscle function required for the power tests was affected through damage to type II muscle fibres. Findings from study 1 indicated that rowers commonly perform strength training three times per week; therefore study 5 investigated the impact of this weekly frequency of strength training on muscle function. Twenty four hours after three bouts of ST within a five day period, trained rowers experienced significant decreases in maximal voluntary contraction, jump height and power stroke tests as well as increases in CK and soreness; however as with study 4, 2000m performance was unaffected. Trends for decreases in peak lactate and anaerobic energy liberation (p < 0.10, Effect Size = 0.40-0.56) were present alongside significant increases in EMG at three sites during the post-ST 2000 m test. These findings suggest a decreased utilisation of the anaerobic capacity coupled with increased central motor drive suggesting a change in muscular recruitment patterns during the follow up 2000 m rowing test. It would appear that following extensive strength training, physiological processes were adapted during subsequent rowing exercise, to compensate for the loss in higher threshold muscle fibre function, in order to affect the same level of rowing performance achieved in the rested state. These findings might suggest that participants operated within a physiological reserve and/or that multiple-exercise-regulation-algorithms exist with which a similar exercise performance can be achieved.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Biomechanical Spectrum of Human Sport Performance

Writing or managing a scientific book, as it is known today, depends on a series of major activities, such as regrouping researchers, reviewing chapters, informing and exchanging with contributors, and at the very least, motivating them to achieve the objective of publication. The idea of this book arose from many years of work in biomechanics, health disease, and rehabilitation. Through exchanges with authors from several countries, we learned much from each other, and we decided with the publisher to transfer this knowledge to readers interested in the current understanding of the impact of biomechanics in the analysis of movement and its optimization. The main objective is to provide some interesting articles that show the scope of biomechanical analysis and technologies in human behavior tasks. Engineers, researchers, and students from biomedical engineering and health sciences, as well as industrial professionals, can benefit from this compendium of knowledge about biomechanics applied to the human body