A research report submitted to the Faculty of Health Sciences, University of the Witwatersrand, in partial fulfillment of the requirements for the degree of Master of Science in Medicine in the field of Biokinetics. 21 June 2018 / Introduction: The purpose of this study was to describe the Endurance Index of automotive workers to determine aerobic capacity to sustain an 8 hour shift. The Endurance Index is the product of Work (in Joules) performed by muscles divided by Peak Heart Rate (in beats per minute). Since there is no clear method for determining full work tolerance (8 hour sustenance) for job specific endurance activities, a new scientific method is warranted. Methods: This was a retrospective study and 44 jobs were randomly selected. In those jobs there was a sample of 101 automotive workers (n = 94 males and n = 6 females). From the 44 jobs, there were 220 endurance activities/tests and peak heart rates and total work performed by muscles was described then these variables were used to calculate Endurance Index which was described for each endurance activity. Results: Peak HR had a mean of 139.85 ±20.96 (100 – 184bpm), total work had a mean of 9224.73 ±5826.04 (897.20 – 33 055) and EI had a mean of 67.14 ±42.88 (8 – 243.10). Total work and EI had significant (p < 0.00) and good positive correlation (r = 0.97). Peak HR and EI had significant (p < 0.01) and poor negative correlation (r = -0.18). Conclusion: The scientific rationale for using Endurance Index as an indicator for aerobic capacity is that the better conditioned an individual the more work that can be produced at lower relative heart rates compared to individuals who are poorly conditioned. So the more the work value and the lower the heart rate value, the better the index. In this study it was found that Endurance index is a good indicator of aerobic capacity since a positive correlation was found between total work and Endurance index and a negative correlation was found between peak heart rate during an endurance activity and Endurance Index. / MT 2019

The purpose of this study was to investigate if a low mixed carbohydrate plus moderate protein supplement, provided during endurance exercise, would improve time to exhaustion in comparison to a traditional 6% carbohydrate supplement in female athletes exercising at or below their ventilatory threshold. Fourteen (n = 14) trained female cyclists and triathletes cycled on two separate occasions for three hours at intensities varying between 45% - 70% VO₂max, followed by a ride to exhaustion at an intensity approximating the individual's VT (average 75.06% VO₂max). Supplements (275ml) were provided every 20 min during exercise and were composed of a 3% carbohydrate mixture + 1.2% protein (CHO+PRO) or a 6% carbohydrate-only (CHO). The CHO+PRO treatment contained a mixture of dextrose, maltodextrin, fructose, and whey protein isolate. The CHO treatment was composed of dextrose only. Time to exhaustion (TTE) was significantly greater with CHO+PRO in comparison to CHO (49.94 ± 7.01 vs 42.36 ± 6.21 min, respectively, p < 0.05). Blood glucose was signifcantly lower during the CHO+PRO (4.07 ± 0.12 mmol x L⁻¹) trial compared to CHO (4.47 ± 0.12 mmol x L⁻¹), with treatment x time interactions occurring from 118 minutes of exercise until exhaustion (p < 0.05). Heart rate was significantly lowered in the CHO+PRO treatment during exercise as compared to CHO (p < 0.05). There were no significant differences for other blood measures, ratings of perceived exertion or carbohydrate and fat oxidation between trials. Results from the present study suggest that the addition of a moderate amount of protein to a low mixed carbohydrate supplement improves endurance performance in females above that of a traditional 6% carbohydrate supplement. Improvement in performance occurred despite CHO+PRO containing a lower carbohydrate and caloric content. It is likely the greater performance seen with CHO+PRO was a result of the carbohydrate protein combination and the use of a mixture of carbohydrate sources. / text

Background: The high frequency of emergency responses and the variety of response environments for firefighting and emergency medical services dictate a potential for high work demands and an increasing need for maintaining above average physical fitness. This study makes use of a retrospective occupational cohort study design to explore the relationships between measures of fitness and injury outcomes. Methods: Data were collected from annual medical exams and injury surveillance records recorded for the years 2004-2009 among commissioned employees of the Tucson Fire Department. Fitness was assessed and contrasted via a submaximal estimate of aerobic capacity and a developed metric and score for comprehensive "fire fitness" encompassing seven separate measures for strength, endurance, flexibility, body composition and aerobic fitness. Individual fitness scores were classified as 'high fit', 'fit', and 'less fit'. The association between the fitness measures and injuries was evaluated using two approaches: log-binomial and time-to-event analyses. Results: The annual injury incidence rate averaged 17.7 per 100 employees. One-third of all injuries (32.9%) resulted from physical exercise activities, while patient transport, training drills, and fireground operations resulted in 16.9%, 11.1% and 10.2% of injuries, respectively. For all job operations, sprains and strains were the most prevalent type of injury, followed by contusions and lacerations. The reliability of fitness and clinical measures showed mean flexibility, grip strength, percent body fat, and resting heart rate each had intraclass correlations (ICC) values above 0.5, suggesting fair to good reliability. In contrast, mean VO2max was an unreliable measure with an ICC of 0.27. Hazard ratios from time-to-event analyses indicated that increases in cardiorespiratory fitness were significantly associated with decreased risk against injury. Similarly, decreases in comprehensive "fire fitness" were associated with an increased risk of injury. Conclusions: These findings add support that improving one's fitness reduces the likelihood of injury. Future research should focus on the relationship between fitness, performance and health outcomes. Individual level fitness improvements should be objectively measured and designed within the functional limitations of that individual, and without subjecting the person to injury in that process.

The purpose of the study was to examine the relationship between treadmill time, maximal oxygen consumption and pace characteristics of the 1.5 and 3 mile runs and to compare the distances and pace characteristics as predictors of aerobic capacity. Subjects were 70 college aged males, ages 18 to 25, enrolled in jogging and conditioning classes at North Texas State University. Three tests were administered: the 1.5 mile run, the 3 mile run and the Bruce treadmill test. The data were analyzed using correlations and factor analysis. Conclusions of the investigation were (1) the 1.5 and 3 mile runs are valid measures of aerobic capacity, (2) the 3 mile run does not significantly increase the correlation between VO2max and endurance runs and (3) pacing characteristics are evident in the 1.5 and 3 mile runs.

Made available in DSpace on 2014-06-11T19:30:52Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-03-16Bitstream added on 2014-06-13T20:40:40Z : No. of bitstreams: 1 santhiago_v_dr_rcla.pdf: 487613 bytes, checksum: 08693467b4d88569bdc7cc8c28ab9031 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Considerando a necessidade de avaliar a capacidade aeróbia de nadadores e assim prescrever as intensidades adequadas de treino durante ciclos de treinamento, vários estudos foram desenvolvidos com diferentes protocolos a fim de identificar instrumentos de aplicabilidade prática capazes de avaliar e quantificar a capacidade aeróbia. Entretanto, ainda existem controvérsias a respeito dos modelos invasivos e não invasivos e exaustivos e não exaustivos que representem de forma mais fidedigna a máxima fase estável de lactato (MFEL). Além disso, existe também, carência de investigações relacionadas à utilização do sistema de nado atado na avaliação de parâmetros fisiológicos, mecânicos e como ferramenta no treinamento de nadadores. Desse modo, o objetivo geral do presente estudo foi padronizar e testar diferentes modelos invasivos e não invasivos de avaliação aeróbia na natação, por meio de protocolos em nados livre e atado, validando-os através da comparação com a MFEL. Para isso, foram avaliados 12 nadadores do sexo masculino durante um período de polimento na natação. Foram utilizados protocolos de MFEL, velocidade crítica (Vcrit), Vcrit obtida por meio do protocolo proposto por Chassain (1986), MFEL em nado atado, força crítica (Fcrit) em nado atado e Fcrit obtida por meio do protocolo proposto por Chassain (1986). Para verificar possíveis diferenças entre as respostas agudas de stress obtidas após a utilização de diferentes protocolos em nados livre e atado, concentrações sanguíneas foram mensuradas. / Considering the need to evaluate the aerobic capacity in swimmers and to prescribe the appropriate intensities of training, several studies were developed with different protocols in order to identify practical applicability instruments capable to evaluate and to quantify the aerobic capacity in swimmers. However, still controversies exist regarding the invasive and non invasive models which represent the maximal lactate steady state (MLSS). The aim of the present study was to standardize and to test differents invasive and non invasive models of aerobic and anaerobic evaluation in the swimming, by protocols in free and tethered swimming, validating them by the comparison with the MFEL. Twelve male swimmers were evaluated during the taper period in the swimming. Protocols of MLSS, critical swimming velocity (CSV), Vcrit obtained through the protocol proposed by Chassain (1986), MFEL in tethered swimming, critical force (CF) in tethered swimming and CF obtained by the protocol proposed by Chassain (1986). To verify possible differences among the stress responses obtained after the use of different protocols in free and tethered swimming, enzymatic plasma concentrations were measured.

Aerobic capacity of aerobic gymnasts while testing in specific and non-specific conditions The aim of the study: to determine an aerobic capacity of aerobic gymnasts while testing in specific and non-specific conditions. Objectives: · To compare submaximum heart rate and respiratory indices during treadmill and step tests. · To compare maximum heart rate and respiratory indices during treadmill and step tests. · To evaluate step test’s using opportunities for testing an aerobic capacity of aerobic gymnasts. Methods: 1. Continuously increasing step test. 2. Continuously increasing treadmill test 3. Measurement of respiratory gas exchange. 4. HR monitoring and recording. 5. Measurement of blood lactate concentration. 6. Anthropometrical measurements. The hypothesis of the study. Incremental increasing step test is able for evaluation of an aerobic capacity, heart rate and respiratory indices, especially submaximum, while testing under specific conditions, i. e. performing physical exercises on the aerobic platform dosing physical load according to the tempo of music. Practical application. The results access the physiological knowledges about aerobic gymnasts aerobic capacity. These data can be used for individualization of the physical loads in aerobic gymnastics. Originality of the study. First time using respiratory gas exchange telemetric system was performed an incremental increasing step test, while the physical load was dosed by music rhythm. The aerobic capacity of... [to full text]

Orientador: Claudio Alexandre Gobatto / Banca: Sergio Augusto Cunha / Banca: Marcelo Papoti / Banca: Mário Mateus Sugizaki / Banca: Sebastião Gobbi / Resumo: Considerando a necessidade de avaliar a capacidade aeróbia de nadadores e assim prescrever as intensidades adequadas de treino durante ciclos de treinamento, vários estudos foram desenvolvidos com diferentes protocolos a fim de identificar instrumentos de aplicabilidade prática capazes de avaliar e quantificar a capacidade aeróbia. Entretanto, ainda existem controvérsias a respeito dos modelos invasivos e não invasivos e exaustivos e não exaustivos que representem de forma mais fidedigna a máxima fase estável de lactato (MFEL). Além disso, existe também, carência de investigações relacionadas à utilização do sistema de nado atado na avaliação de parâmetros fisiológicos, mecânicos e como ferramenta no treinamento de nadadores. Desse modo, o objetivo geral do presente estudo foi padronizar e testar diferentes modelos invasivos e não invasivos de avaliação aeróbia na natação, por meio de protocolos em nados livre e atado, validando-os através da comparação com a MFEL. Para isso, foram avaliados 12 nadadores do sexo masculino durante um período de polimento na natação. Foram utilizados protocolos de MFEL, velocidade crítica (Vcrit), Vcrit obtida por meio do protocolo proposto por Chassain (1986), MFEL em nado atado, força crítica (Fcrit) em nado atado e Fcrit obtida por meio do protocolo proposto por Chassain (1986). Para verificar possíveis diferenças entre as respostas agudas de stress obtidas após a utilização de diferentes protocolos em nados livre e atado, concentrações sanguíneas foram mensuradas. / Abstract: Considering the need to evaluate the aerobic capacity in swimmers and to prescribe the appropriate intensities of training, several studies were developed with different protocols in order to identify practical applicability instruments capable to evaluate and to quantify the aerobic capacity in swimmers. However, still controversies exist regarding the invasive and non invasive models which represent the maximal lactate steady state (MLSS). The aim of the present study was to standardize and to test differents invasive and non invasive models of aerobic and anaerobic evaluation in the swimming, by protocols in free and tethered swimming, validating them by the comparison with the MFEL. Twelve male swimmers were evaluated during the taper period in the swimming. Protocols of MLSS, critical swimming velocity (CSV), Vcrit obtained through the protocol proposed by Chassain (1986), MFEL in tethered swimming, critical force (CF) in tethered swimming and CF obtained by the protocol proposed by Chassain (1986). To verify possible differences among the stress responses obtained after the use of different protocols in free and tethered swimming, enzymatic plasma concentrations were measured. / Doutor

Children with cerebral palsy have lesser cardiorespiratory endurance (or aerobic capacity) and less physical activity than children who are developing normally. Cardiorespiratory problems are linked to a higher risk of noncommunicable diseases and premature aging. The goal of this research is to discover aspects that can be added in physiotherapy practice to ensure a long-term improvement in aerobic capacity in children with cerebral palsy while engaging in physical activity. Also investigated is the effect of aerobic capacity on functional abilities. A systematic review of the literature was undertaken utilizing the PubMed, Cochrane Library, ScienceDirect, and PEDro databases. The child's cardiorespiratory fitness appears to improve when they engage in high- intensity, goal-directed physical activity. The child's adherence appears to be aided by a motivating intervention and the removal of environmental barriers to the activity's practice. This allows for a long-term increase in aerobic capacity. It was impossible to draw a direct link between this improvement and functional capacity. Few studies have incorporated cerebral palsy and low global motor skills in recent years. Despite the importance of the findings, their heterogeneity prevents generalizable suggestions for all children with cerebral...

<p>It is commonly accepted that aerobic exercise increases hippocampal neurogenesis, learning and memory, as well as stress resiliency. However, human populations are widely variable in their inherent aerobic fitness as well as their capacity to show increased aerobic fitness following a period of regimented exercise. It is unclear whether these inherent or acquired components of aerobic fitness play a role in neurocognition. To isolate the potential role of inherent aerobic fitness, we exploited a rat model of high (HCR) and low (LCR) inherent aerobic capacity for running. At a baseline, HCR rats have two- to three-fold higher aerobic capacity than LCR rats. We found that HCR rats also had two- to three- fold more young neurons in the hippocampus than LCR rats as well as rats from the heterogeneous founder population. We then asked whether this enhanced neurogenesis translates to enhanced hippocampal cognition, as is typically seen in exercise-trained animals. Compared to LCR rats, HCR rats performed with high accuracy on tasks designed to test neurogenesis-dependent pattern separation ability by examining investigatory behavior between very similar objects or locations. To investigate whether an aerobic response to exercise is required for exercise-induced changes in neurogenesis and cognition, we utilized a rat model of high (HRT) and low (LRT) aerobic response to treadmill training. At a baseline, HRT and LRT rats have comparable aerobic capacity as measured by a standard treadmill fit test, yet after a standardized training regimen, HRT but not LRT rats robustly increase their aerobic capacity for running. We found that sedentary LRT and HRT rats had equivalent levels of hippocampal neurogenesis, but only HRT rats had an elevation in the number of young neurons in the hippocampus following training, which was positively correlated with accuracy on pattern separation tasks. Taken together, these data suggest that a significant elevation in aerobic capacity is necessary for exercise-induced hippocampal neurogenesis and hippocampal neurogenesis-dependent learning and memory. To investigate the potential for high aerobic capacity to be neuroprotective, doxorubicin chemotherapy was administered to LCR and HCR rats. While doxorubicin induces a progressive decrease in aerobic capacity as well as neurogenesis, HCR rats remain at higher levels on those measures compared to even saline-treated LCR rats. HCR and LCR rats that received exercise training throughout doxorubicin treatment demonstrated positive effects of exercise on aerobic capacity and neurogenesis, regardless of inherent aerobic capacity. Overall, these findings demonstrate that inherent and acquired components of aerobic fitness play a crucial role not only in the cardiorespiratory system but also the fitness of the brain.</p> / Dissertation

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